JP4801604B2 - Sheet conveying apparatus, image reading apparatus, and image forming apparatus - Google Patents

Description

  The present invention relates to a sheet conveying apparatus, a copier equipped with the sheet conveying apparatus, a facsimile, a printer, a printing machine, an inkjet recording apparatus, an image reading apparatus such as a scanner, or a combination machine combining at least two of them. The present invention relates to an image forming apparatus.

  Conventionally, image forming apparatuses such as copiers, facsimiles, printers, printers, ink jet recording apparatuses, etc., including PPC (plain paper copier: plain paper copiers), etc., are designed to reduce the size of the entire apparatus. For transporting and supplying an image forming medium or a sheet-like recording medium (hereinafter referred to as “sheet”), which is a medium on which the image is formed, from the sheet storage unit or the sheet stacking unit for stacking sheets to the image forming unit main body The conveying means also tends to be downsized. Hereinafter, the sheet storing means for storing the sheet will be described as a representative.

  Further, the image forming apparatus generally has a model corresponding to various sheet sizes (hereinafter referred to as “paper size”) and sheet types (hereinafter referred to as “paper type”). In such an image forming apparatus model, for example, a sheet (hereinafter, referred to as “paper” illustratively) having several paper sizes and types is stored in advance in a sheet storage unit, and the user selects as appropriate. The sheet can be fed from the sheet storing means or the sheet automatically selected by the image forming apparatus. Accordingly, in the case of such a configuration, the sheet storage unit occupies more space in the image forming apparatus and consumes it, so that the demand for downsizing the transport unit is increased.

For these reasons, the conveyance path formed between the sheet storage unit and the image forming unit main body in the image forming apparatus depends on the positional relationship between the two. The space occupied is reduced. As a result, a curved portion having a curved shape is provided on the conveyance path in order to continuously and smoothly change the conveyance direction, and the curvature radius of the curved portion is used as a sheet normally used in an image forming apparatus. Is set to a relatively small radius that allows the standard recording paper to be conveyed.
As a sheet conveying apparatus in such an image forming apparatus, for example, a conventional technique described in Japanese Patent Application Laid-Open No. 2004-338923 can be cited (see Patent Document 1). That is, as shown in FIGS. 6 and 7 of the same publication, a sheet storage unit that stores a predetermined number of sheets of a predetermined size and type on each stage on the lower side of the image forming unit main body. A sheet feeding tray is arranged, and between the sheet feeding tray and the image forming unit main body, one sheet is pulled out in a substantially horizontal direction of the sheet feeding tray which is the selected stage, and the upper image forming unit main body The sheet conveying device for feeding toward is provided.

Hereinafter, the reference numerals shown in the drawings of the above-mentioned Japanese Patent Application Laid-Open No. 2004-338923 will be appropriately described in parentheses. The sheet is separated and sent out, and is conveyed to the main body of the image forming unit through a conveyance path having a curvature portion formed by the upper guide plate (8) and the lower guide plate (7). The curvature portion is formed of a curved fixed guide member including an upper guide plate (8) and a lower guide plate (7). When the sheet (P) passes through the curvature portion, the lower guide plate ( 7) As the conveyance proceeds along the sheet 7), the path of the sheet (P) is corrected so as to be pressed by the upper guide plate (8), and the elastic deformation located at the outlet of the lower guide plate (7) is achieved. The conveying roller pair (5) is reached along the possible guide piece (6). Hereinafter, the upper guide plate (8) and the lower guide plate (7) are referred to as “curved fixed guide members”.
However, in the sheet conveying apparatus configured as described above, when trying to convey a sheet of special paper (P) having high rigidity such as recording paper such as thick paper or an envelope, the radius of curvature of the curvature portion of the conveying path is small. Therefore, since the resistance when the sheet (P) is conveyed while being bent according to the curvature thereof is significantly larger than that of a sheet such as plain paper for copying, a sheet (P ) Cannot be advanced, causing jams and poor conveyance, resulting in a failure to perform a stable feeding operation.

  The above operation will be described in more detail as follows. When the sheet (P) has a leading end (front end) in the conveying direction of the sheet (P) reaches a curved fixed guide member composed of an upper guide plate (8) and a lower guide plate (7), the curved fixed guide The first half of the sheet (P) on the leading end side is curved in the thickness direction by the member. For this reason, when the highly rigid sheet (P) is conveyed, the force with which the highly rigid sheet (P) resists bending increases, and the resistance force that prevents the conveyance also increases. Therefore, the leading end of the highly rigid sheet (P) does not reach the downstream conveying roller pair (5), and the highly rigid sheet (P) is conveyed only by the upstream roller pair (2a, 2b). When the high-rigidity sheet (P) is curved by the curved fixed guide member, the resistance generated from the curved high-rigidity sheet (P) can be obtained only by the conveying force by the upstream roller pair (2a, 2b). As a result, there is a shortage of force that advances in the transport direction relative to the force. For this reason, conveyance failure such as skewing in which the center line of the highly rigid sheet (P) does not coincide with the center line of the conveyance path, or the highly rigid sheet (P) is caught by the curved fixed guide member and stopped. Paper jam is likely to occur.

Therefore, in Japanese Patent Application Laid-Open No. 2004-338923, in a sheet feeding device that conveys a sheet fed from a first conveying unit to a second conveying unit that is positioned downstream in the conveying direction and substantially vertically above. A pair of linear guide members are provided between the first conveyance unit and the second conveyance unit, and a sheet feeding device that conveys a sheet by the guide of the linear guide member has been proposed. According to this paper feeding device, since the guide member is not a curved shape but a straight linear guide member, the conveyance load can be suppressed to a low level, that is, a rapid increase in load can be suppressed. It is said that poor conveyance can be prevented.
In other words, according to the sheet feeding device, the deformed portion on the conveyed sheet is not concentrated on one curve by the curved guide member, but near the front and rear ends of the linear guide member in the conveyance direction. Since the linear guide member is installed in a slanted posture with a substantially intermediate angle so that the degree of bending at these two places is substantially equal and the same, it can be conveyed at the time of conveyance. It is said that a sudden increase in load can be suppressed. That is, since the sheet changes its traveling direction, the curved portion is divided into two locations: a location where the sheet is delivered from the upstream roller pair to the linear guide member, and a location where the sheet is delivered from the linear guide member to the downstream roller pair. At least, the degree of bending of each portion becomes small, and accordingly, the resistance generated by bending at each portion can be kept low, so that it is possible to avoid a sharp increase in the transport load.

It has the 1st, 2nd conveyance means comprised like the said Unexamined-Japanese-Patent No. 2004-338923 (patent document 1), and it is 2nd between a 1st conveyance means and a 2nd conveyance means. 2. Description of the Related Art A reversing guide member having an inclined surface reaching a conveying unit is provided, and the reversing guide member is configured to be movable toward a second conveying unit (for example, Patent Document 2). reference).
According to this paper feeding device, when the rear end of the sheet comes into contact with the reverse guide member, the reverse guide member is displaced in a direction substantially the same as the direction in which the rear end of the paper is in contact. It is said that it can reduce the playing sound because it can absorb the shock at the time.

In addition, a plurality of sheet storage units that store sheets, a conveyance path and a sheet feeding unit that are individually provided in each sheet storage unit, and the ends of these conveyance paths merge into one common conveyance path. And at least the conveyance path provided in the sheet accommodation means that accommodates the highly rigid sheet has a different radius of curvature of the first curvature part when joining the common conveyance path provided at the end of the conveyance path. There is known a sheet feeding apparatus that is set to be larger than the radius of curvature of the other curvature portion when the conveyance paths are joined (for example, see Patent Document 3).
According to this sheet feeding device, a highly rigid sheet is curved to the same extent as an ordinary sheet when passing on the first curvature portion having a large curvature radius while traveling on the transport path. In contrast, since the sheet is continuously curved and sufficiently advanced as compared with the normal sheet, the resistance during the conveyance can be reduced, and the sheet can be conveyed by reaching the common conveyance path without causing stagnation or delay of the sheet.

The reversing roller pair has a reversing conveyance path for conveying and guiding the sheet fed by the reversing roller pair, and the reversing conveyance path has a direction changing portion for changing the sheet conveying direction. In addition, by disposing a roller that is rotatable inward in the direction changing portion in a direction perpendicular to the sheet conveying direction, the sheet fed into the reverse conveying path is sent out while being brought into contact with the roller. A sheet inverting means provided in a forming apparatus is known (for example, see Patent Document 4).
According to this sheet reversing means, the fed sheet is in the above-mentioned direction changing portion, and the inner contact portion always comes into contact with the roller, and this roller is driven to rotate as the sheet is conveyed in the conveying direction. Compared to the conventional guide plate, the conveyance resistance can be reduced, that is, the frictional resistance generated between the fixed guide member and the moving sheet is eliminated, and the guide for changing the conveyance direction at the direction changing portion. I can do it.

JP 2004-338923 A (pages 1 to 3, FIGS. 1 to 7) Japanese Patent Laying-Open No. 2005-89008 (pages 2 and 3, FIGS. 4 and 5) Japanese Patent Laid-Open No. 10-129883 (pages 1 and 2, FIG. 1) Japanese Patent Laying-Open No. 2005-1771 (pages 1 and 2, FIG. 1)

However, in the sheet conveying apparatus described in Patent Document 1, since the fixing member is arranged for guiding the sheet to be conveyed, the sheet conveying apparatus between the sheet to be conveyed and the fixed guide member is arranged. The speed difference is not eliminated, and there is a problem in that a resistance acting in a direction that hinders the conveyance of the sheet is always generated between the two regardless of the shape of the guide member and the installation posture, resulting in a conveyance load.
That is, in the conventional configuration, the effect of avoiding the above-described conveyance failure and jam is insufficient, and the linear guide member causes a conveyance load even if a rapid increase in the conveyance load can be suppressed. It can be said that there is no change. In particular, when a highly rigid sheet (sheet) such as thick paper or an envelope is conveyed, the above-described conveyance failure, jam, and the trailing sound of the sheet become noticeable.

  In the configuration provided with the reversal guide member described in Patent Document 2, even if it is a movable member in the sense that it can be displaced in the direction in which the rear end of the paper is in contact, the guide for changing the orientation of the paper is a fixed guide member. Similarly, when guiding by changing the direction, the relative speed difference between the sheet and the reverse guide member is not eliminated, and a transport load is generated. In particular, when a highly rigid sheet (sheet) such as thick paper or an envelope is conveyed, the above-described conveyance failure, jam, and the trailing sound of the sheet become noticeable.

  In addition, as in the technique described in Patent Document 3, even in a configuration in which a dedicated conveyance path having a predetermined large radius of curvature is provided, the sheet traveling on this dedicated conveyance path is gently curved so that the sheet is removed from the conveyance path. Even if the transport resistance received is reduced, the transport load is similarly generated. In particular, when transporting highly rigid paper (sheets) such as thick paper and envelopes, the above-mentioned transport failure and jamming become noticeable.

  Further, as in the technique described in Patent Document 4, in a configuration in which a movable member such as a roller is provided at a predetermined position of the inner conveyance path portion in the direction change portion of the conveyance path, in the conveyance process, by the inner roller, Even if the frictional resistance between the two in the state where the intermediate portion between the front and rear ends of the seat is supported can be particularly effectively reduced, the state before and after such a state, that is, the outside of the direction changing portion There is a lack of consideration for the conveyance load when the conveyance path portion and the sheet are in contact with each other, and no particular mention is made of the behavior of the sheet leading edge and the sheet trailing edge during the conveyance process. In particular, when a highly rigid sheet (sheet) such as thick paper or an envelope is conveyed, the above-described conveyance failure, jam, and the trailing sound of the sheet become noticeable.

  Accordingly, the applicant of the present application has provided an invention (for example, August 7, 2006) aimed at providing a novel sheet conveying apparatus capable of solving the problems of the prior art and an image forming apparatus having the sheet conveying apparatus. This refers to a novel invention proposed in Japanese Patent Application No. 2006-214779 and the like, and hereinafter referred to as “prior application invention”. Details of the example to which the invention of the prior application is applied will be described later before the embodiment of the present invention is described. According to the present invention, a compact and space-saving, simple and low-cost configuration, a sheet conveying apparatus excellent in compatibility with sheet types (paper types), an image reading apparatus including the sheet conveying apparatus, and a sheet An image forming apparatus including a transport device and / or an image reading device can be realized and provided.

  However, it has been found that the following problems remain in putting the invention of the prior application into practical use. That is, it is downstream from the second conveying means provided after the curvature of the sheet conveying path formed between the first conveying means and the second conveying means and having a curved curvature portion having a relatively small radius of curvature. A sheet that is conveyed to the side, particularly for a stiff sheet such as cardboard, is restored to an elastic deformation (hereinafter also referred to as “buckling”) that occurs when the sheet is transferred from the curvature portion to the belt. Since force works, it tries to be conveyed toward the curvature outward direction. At this time, since the sheet is conveyed while being brought into contact with the outer side of the guide member such as the guide plate pair provided on the downstream side of the second conveying means with a strong contact pressure, the wear of the guide member such as the guide plate or the layout Restrictions arise and the device cannot be downsized. Therefore, the main object of the present invention is to solve the above problems with a simple and low-cost configuration while being compact and space-saving.

The purpose of each main claim is as follows.
The sheet held between the first conveying unit and the second conveying unit is conveyed while buckling, but the sheet conveying direction of the sheet conveyed downstream from the second conveying unit is large in sheet thickness. The closer to the waist (the stronger the waist), the direction (outer direction, that is, the direction of the belt conveying surface of the belt conveying means) in which deformation / buckling is to be restored. In particular, in the case of a stiff and highly rigid sheet such as cardboard, the sheet is conveyed while contacting with a strong contact pressure on the guide member arranged on the downstream side of the second conveying means, so there is a concern about the wear of the guide member. Is done. In order to reduce the conveyance space for the purpose of downsizing the apparatus, an elastic member may be used as a guide member. However, in order to guide a sheet having a strong waist, it is necessary to use a member having a higher elastic force. There is a disadvantage in terms of cost.

  SUMMARY OF THE INVENTION An object of the present invention is to change the sheet conveying direction conveyed by the second conveying means according to the layout downstream of the second conveying means of the apparatus. By setting the transport direction, the problem is solved.

  When it is desired to change the transport direction before and after the entry of the second transport means, in the transport means using the conventional roller pair, the transport means does not smoothly enter the clamping portion (nip portion), and the transport after the entrance is performed. In some cases, the leading edge of the sheet collides with a roller facing in the direction, causing damage such as damage or jamming of the leading edge of the sheet.

  Accordingly, an object of the inventions of claims 4 and 11 is that the shaft of the belt holding rotating member on the side forming the clamping portion is located downstream of the shaft of the rotary conveying member in the sheet conveying direction of the second conveying means. By shifting the sheet conveying direction after entering the clamping unit to a direction facing the conveying surface of the belt, while smoothly moving the second conveying unit into the clamping unit, For example, it is intended to prevent wear of the guide member disposed in the downstream portion on the belt side and to improve the layout margin of the downstream portion.

The object of the invention described in claims 5 and 11 is that the material of the belt holding and rotating member on the side forming the clamping part (nip part) in the belt conveying means is made of an elastic member, so that the second conveying means is opposed. Since the nipping portion (nip portion) can be formed large between the belt holding and rotating members, the conveying force of the second conveying means can be increased, and the sheet conveying direction of the sheet from the nipping portion (hereinafter referred to as “exit angle”). ”) Can be formed in a direction facing the belt, and therefore, the sheet transport direction after entering the sheet is set to a direction facing the transport surface of the belt.
Also, since the apparent rubber hardness of the belt is low, it reduces noise when the leading edge of the sheet comes into contact with the belt and when the trailing edge of the sheet bounces toward the belt Is to make it possible.

The object of the invention described in claims 6 and 11 is that the belt of the belt conveying means is formed of a rubber having a relatively low hardness, so that a clamping part (nip part) is formed between the belt holding and rotating members facing each other of the second conveying means. Therefore, the conveying force of the second conveying means can be increased, and the sheet conveying direction of the sheet from the clamping unit (hereinafter also referred to as “exit angle”) is formed in a direction facing the belt. Therefore, the sheet conveyance direction after entering the sheet is set to a direction facing the conveyance surface of the belt.
In addition, since the rubber hardness of the belt itself is relatively low, the noise when the leading edge of the sheet comes into contact with the belt is reduced, and when the trailing edge of the sheet bounces to the belt side, the noise that occurs when the trailing edge of the sheet hits the belt is reduced. It is to make it possible.

The object of the present invention is to divide the belt conveying means into a plurality of parts in the sheet width direction perpendicular to the sheet conveying direction, so that each belt width can be reduced and the belt width direction can be reduced. It is intended to realize stable belt conveyance by reducing the influence of the thickness deviation.
Further, the belt holding and rotating member shaft on the side forming the clamping portion in the belt conveying means arranged on the center side in the sheet width direction is the side forming the clamping portion in the belt conveying means arranged on both sides in the sheet width direction. The sheet conveying direction of the sheet can be changed to a direction opposite to the conveying surface of the belt by disposing and shifting to the downstream side in the sheet conveying direction of the second conveying unit with respect to the shaft of the belt holding and rotating member. The rear end of the sheet passes through the belt conveying means, and for example, the noise (sound noise) is reduced when the sheet is placed against a guide member provided on the downstream side.

  An object of the invention according to claims 8 and 11 is to displace the shaft of the belt holding and rotating member on the side forming the clamping portion in the second conveying means to the downstream side in the sheet conveying direction of the second conveying means. By disposing the displacing means including the driving means, the axis of the belt holding and rotating member on the side forming the clamping portion can be changed in the above direction according to the sheet type, particularly the thickness of the sheet. Specifically, when the leading end of the sheet enters the nipping portion, the position of the belt holding rotating member on the side forming the nipping portion is opposed to the other of the opposed pairs of the nipping and conveying means (the axis of the rotation conveying member) ( By displacing the shaft of the belt holding and rotating member on the side that forms the nipping part to the downstream side in the sheet conveying direction of the second conveying unit immediately before the trailing edge of the sheet passes through the nipping part. Further, the rear end of the sheet passes through the belt conveying means and the sandwiching portion, and for example, a sound (striking sound) is reduced when the sheet is placed against a guide member provided on the downstream side.

  The object of the inventions described in claims 9 and 11 is to achieve the objects of the inventions described in claims 8 and 11 by a low-cost and easy control method by using a solenoid as the driving means of the displacement means.

  The object of the invention described in claims 10 and 11 is to change the amount of displacement according to various thicknesses of the sheet by using, for example, a stepping motor, which is a drive motor that is rotationally driven by pulse input, as the drive means of the displacement means. Thus, the object of the inventions of claims 8 and 11 can be achieved more effectively than claim 9.

  An object of the invention described in claim 12 is provided with an automatic document feeder (ADF) for automatically feeding a document sheet as an image reading device having the sheet conveying device according to any one of claims 1 to 11. By using the image reading apparatus, it is possible to improve the transportability of a relatively rigid original sheet such as a thick original in an automatic original feeder or the like with a space-saving, low-cost and simple configuration.

  An object of the invention described in claim 13 is to automatically feed an original sheet as an image reading apparatus having the sheet conveying apparatus according to any one of claims 1 to 11 and / or the image reading apparatus according to claim 12. By using an image reading device equipped with an automatic document feeder (ADF, ARDF), etc., it is possible to improve sheet conveying performance with relatively high rigidity such as thick paper in the sheet conveying device with a space-saving, low-cost and simple configuration. Another object of the present invention is to realize and provide an image forming apparatus capable of improving the transportability of a relatively rigid original sheet such as a thick original in an automatic original feeder.

  The object of the invention described in claim 14 is that the image forming apparatus is a copying machine, a facsimile machine, a printer, a printing machine, an ink jet recording apparatus, or a composite machine combining at least two of them. It is to achieve the object of the described invention.

  In order to solve the above-mentioned problems and achieve the above-mentioned object, the present inventors have conducted extensive studies and conducted tests and the like described in the examples of the prior application invention described below, examples, etc. A simple structure called a moving guide is conceived as a simple structure that can convey a relatively high-stiffness sheet such as cardboard or an envelope without causing any defective conveyance or jamming regardless of the type. As a specific means, belt conveying means having the simplest configuration has been variously devised and put into practical use. The present invention has been made on the basis of the results supported by such tests.

In order to solve the above-described problems and achieve the above-mentioned object, the invention according to each claim employs the following characteristic means / invention-specific matters (hereinafter referred to as “configuration”).
According to the first aspect of the present invention, a first conveying unit that conveys a sheet, and a sheet that is disposed downstream of the first conveying unit in the sheet conveying direction and that has been conveyed by the first conveying unit is the first conveying unit. Second conveying means for conveying in a sheet conveying direction different from the sheet conveying direction of the conveying means, and at least the second conveying means of the first conveying means and the second conveying means holds the sheet. And a nipping / conveying means for forming a nipping portion for conveying, and disposed in an outer direction of a sheet conveying path formed between the first conveying means and the second conveying means, A sheet conveying apparatus including a movement guide unit that moves and guides a sheet toward the clamping unit, and changes the sheet conveyance direction of the sheet conveyed by the second conveyance unit to a direction opposite to the movement guide unit. Specially configured To.

  According to a second aspect of the present invention, a first conveying unit that conveys a sheet and a sheet that is disposed downstream of the first conveying unit in the sheet conveying direction and that has been conveyed by the first conveying unit is the first conveying unit. A second conveying unit that conveys in a sheet conveying direction different from the sheet conveying direction of the first conveying unit, a first sheet conveying path formed between the first conveying unit and the second conveying unit, and a second A second sheet conveying path that is different from the first sheet conveying path, the first sheet conveying path, and the second sheet conveying path are formed from the upstream of the conveying means to the second conveying means. A merging / conveying path that merges upstream of the conveying means, and a movement guide means that is disposed in a contour direction of the merging / conveying path and moves / guides the sheet toward the second conveying means, At least the first of the transport means and the second transport means The conveying means is a sheet conveying apparatus which is a nipping / conveying means for forming a nipping portion for nipping and conveying the sheet, the sheet conveying direction of the sheet conveyed by the second conveying means being set to the movement guide means. It is characterized in that it can be changed in the facing direction.

  According to a third aspect of the present invention, in the sheet conveying apparatus according to the first or second aspect, the movement guide unit is a belt conveying unit including a belt that conveys the sheet toward the clamping unit, and the second conveying unit. The sheet conveying direction of the sheet conveyed by the means can be changed to a direction opposite to the conveying surface in contact with the sheet of the belt.

  According to a fourth aspect of the present invention, in the sheet conveying apparatus according to the third aspect, the belt conveying means is configured such that one of the opposed pairs of the nipping and conveying means in the second conveying means holds the belt so that the belt can run. At least a pair of belt holding and rotating members that are axially supported are provided, and the other of the opposed pair is a rotationally supported rotationally supported member that is on the side that forms the clamping portion with respect to the shaft of the rotationally conveyed member. The shaft of the belt holding and rotating member is arranged so as to be biased to the downstream side in the sheet conveying direction of the second conveying unit.

  According to a fifth aspect of the present invention, in the sheet conveying apparatus according to the third or fourth aspect, the belt conveying means is configured such that one of the opposed pairs of the nipping and conveying means in the second conveying means holds the belt so that it can run. In addition, at least a pair of belt holding and rotating members that are pivotally supported are provided, and the belt holding and rotating member on the side that forms the clamping portion is formed of an elastic member.

  According to a sixth aspect of the present invention, in the sheet conveying apparatus according to any one of the third to fifth aspects, the belt is formed of a rubber having a relatively low hardness.

  The invention according to claim 7 is the sheet conveying apparatus according to any one of claims 3 to 6, wherein the belt conveying means is configured such that one of the opposed pairs of the nipping and conveying means in the second conveying means is the It has at least a pair of belt holding and rotating members that hold the belt so that it can run and are pivotally supported, and the belt conveying means is divided into a plurality of parts in the sheet width direction orthogonal to the sheet conveying direction, In the belt conveying means disposed on the center side in the sheet width direction, the shaft of the belt holding and rotating member on the side forming the clamping portion is clamped in the belt conveying means disposed on both sides in the sheet width direction. It is characterized in that it is arranged so as to be biased toward the downstream side in the sheet conveying direction of the second conveying means with respect to the axis of the belt holding and rotating member on the side forming the portion.

  According to an eighth aspect of the present invention, in the sheet conveying apparatus according to the third aspect, the belt conveying means is configured such that one of the opposed pairs of the nipping and conveying means in the second conveying means holds the belt so that it can run. At least a pair of belt holding and rotating members that are pivotally supported, and depending on the sheet type, the shaft of the belt holding and rotating member on the side that forms the clamping portion is disposed downstream of the second conveying means in the sheet conveying direction. It has the displacement means provided with the drive means to displace to the side.

  According to a ninth aspect of the present invention, in the sheet conveying apparatus according to the eighth aspect, the driving means is a solenoid.

  According to a tenth aspect of the present invention, in the sheet conveying apparatus according to the eighth aspect, the drive means is a drive motor that is rotationally driven by a pulse input.

  The invention according to claim 11 is the sheet conveying apparatus according to any one of claims 1 to 10, wherein the sheet is a sheet having relatively high rigidity.

  According to a twelfth aspect of the present invention, there is provided an image reading apparatus comprising the sheet conveying apparatus according to any one of the first to eleventh aspects.

  A thirteenth aspect of the present invention is an image forming apparatus including the sheet conveying device according to any one of the first to eleventh aspects and / or the image reading device according to the twelfth aspect.

  According to a fourteenth aspect of the present invention, in the image forming apparatus according to the thirteenth aspect, the image forming apparatus is one of a copying machine, a facsimile machine, a printer, a printing machine, and an ink jet recording apparatus, or at least two of them. It is a combined multifunction device.

According to the present invention, a novel sheet conveying apparatus, an image reading apparatus including the sheet conveying apparatus, a sheet conveying apparatus and / or an image forming apparatus including the image reading apparatus are realized and provided by solving the above problems. Can do.
That is, according to the present invention, by solving the above-mentioned problems and problems, even a sheet having a relatively high rigidity (strong waist) such as cardboard can be achieved with a simple and low-cost configuration while saving space. , A sheet conveying apparatus capable of conveying without problems on the downstream side of the sheet conveying path in the second conveying means, an image reading apparatus including the sheet conveying apparatus, an image forming apparatus including the sheet conveying apparatus and / or the image reading apparatus. An apparatus can be realized and provided.

The following are specific effects for each of the claimed inventions.
According to the first, second, third, and eighth aspects of the present invention, the sheet conveying direction of a sheet conveyed by the second conveying unit, particularly a sheet having a relatively high rigidity such as cardboard, is determined by the second conveying unit of the apparatus. It can be set according to the layout on the downstream side.

  According to the fourth and eighth aspects of the present invention, the shaft of the belt holding rotating member on the side forming the clamping portion (nip portion) is arranged in the sheet conveying direction of the second conveying means with respect to the axis of the rotating conveying member. By shifting to the downstream side, the sheet conveying direction after entering the clamping unit is changed to a direction facing the conveying surface of the belt while smoothly entering the clamping unit of the second conveying unit. For example, it is possible to prevent wear of the guide member disposed in the downstream portion on the belt side, and to improve the layout margin of the downstream portion.

According to invention of Claim 5 and 8, the material of the belt holding | maintenance rotation member in the side which forms the clamping part (nip part) in a belt conveyance means is comprised with an elastic member, and the 2nd conveyance means opposes. Since the nipping portion (nip portion) can be formed large between the belt holding and rotating members, the conveying force of the second conveying means can be increased, and the sheet conveying direction of the sheet from the nipping portion (hereinafter referred to as “exit angle”). ”) Can be formed in a direction facing the belt, so that the sheet conveyance direction after entering the sheet can be a direction opposite to the conveyance surface of the belt.
In addition, since the apparent hardness (for example, rubber hardness) of the belt made of an elastic member is low, the sound when the front end of the sheet comes into contact with the belt, and the rear end of the sheet It is possible to reduce the squeaking noise that occurs when hitting the belt.

According to the sixth and eighth aspects of the present invention, the belt of the belt conveying means is formed of a rubber having a relatively low hardness, so that the nipping portion (nip portion) is formed between the belt holding and rotating members facing each other of the second conveying means. Therefore, it is possible to increase the conveying force of the second conveying unit and to form the sheet conveying direction of the sheet from the clamping unit in a direction opposite to the conveying surface of the belt. The sheet conveyance direction after entering can be set to a direction facing the conveyance surface of the belt.
In addition, since the rubber hardness of the belt itself is relatively low, the noise when the leading edge of the sheet comes into contact with the belt, and the noise generated when the trailing edge of the sheet hits the belt when the trailing edge of the sheet bounces toward the belt are reduced. It becomes possible.

According to the seventh and eighth aspects of the present invention, the belt conveying means is divided into a plurality of parts in the sheet width direction orthogonal to the sheet conveying direction, whereby each belt width can be reduced and the belt width direction. It is possible to reduce the influence of the thickness deviation and to realize stable belt conveyance.
Further, the belt holding and rotating member shaft on the side forming the clamping portion in the belt conveying means arranged on the center side in the sheet width direction is the side forming the clamping portion in the belt conveying means arranged on both sides in the sheet width direction. The sheet holding direction of the second conveying means is shifted to the downstream side in the sheet conveying direction of the second conveying means, so that the sheet conveying direction of the sheet can be changed to a direction facing the conveying surface of the belt, For example, it is possible to reduce noise (sound noise) when the trailing edge of the sheet passes through the belt conveying means and is applied to a guide member provided on the downstream side, for example.

  According to the eighth and eleventh aspects of the present invention, the driving means for displacing the shaft of the belt holding rotation member on the side forming the clamping portion in the second conveying means to the downstream side in the sheet conveying direction of the second conveying means. The shaft of the belt holding rotating member on the side that forms the clamping portion is moved to the downstream side in the sheet conveying direction of the second conveying means according to the sheet type, particularly the thickness of the sheet. Thus, when the leading end of the sheet enters the clamping unit, the axis of the belt holding rotating member on the side forming the clamping unit is set to the other of the opposing pair of the clamping conveyance means (rotating conveyance member) Immediately before the sheet exits the nipping part, the axis of the belt holding rotating member on the side that forms the nipping part is positioned downstream of the second conveying means in the sheet conveying direction. By displacing For example, the rear end of a sheet having a relatively high rigidity such as a thick sheet passes through the belt conveying means and the sandwiching portion, and for example, a sound (sound noise) is reduced when the sheet hits a guide member provided on the downstream side. It becomes possible.

  According to the ninth and eleventh aspects of the present invention, by using a solenoid as the driving means for the displacement means, the effects of the eighth and eleventh aspects can be achieved with a low-cost and easy control method.

  According to the tenth and eleventh aspects of the present invention, the amount of displacement according to various thicknesses of the sheet can be obtained by using a drive motor (for example, a stepping motor) that is driven to rotate by pulse input as the drive means of the displacement means. Since it can be changed, the effects of the inventions of claims 8 and 11 can be achieved more effectively than claim 9.

  According to the twelfth aspect of the present invention, the image reading apparatus having the sheet conveying apparatus according to any one of the first to eleventh aspects includes an automatic document feeder (ADF) that automatically feeds a document sheet. By using the image reading apparatus, it is possible to improve the conveyance of a relatively rigid original sheet such as a thick original in an automatic original feeder or the like with a space-saving, low-cost and simple configuration.

  According to a thirteenth aspect of the present invention, an original sheet is automatically fed as an image reading apparatus having the sheet conveying apparatus according to any one of the first to eleventh aspects and / or the image reading apparatus according to the twelfth aspect. By adopting an image reading device equipped with an automatic document feeder (ADF, ARDF), etc., it is possible to improve sheet conveyance performance with relatively high rigidity such as thick paper in the sheet conveyance device with a space-saving, low-cost and simple configuration. Alternatively, it is possible to realize and provide an image forming apparatus that improves the transportability of a relatively rigid original sheet such as a thick original in an automatic original feeder.

  According to the fourteenth aspect of the present invention, the image forming apparatus is any one of a copying machine, a facsimile, a printer, a printing machine, and an ink jet recording apparatus, or a combined machine combining at least two of them. The effects of the described invention are exhibited.

  Hereinafter, embodiments of the present invention (hereinafter referred to as “embodiments”) including the best mode for carrying out the present invention will be described with reference to the drawings. Constituent elements such as members and components having the same function and shape, etc. over the examples, embodiments, modifications, examples, etc. of the sheet conveying device to which the above-mentioned invention of the prior application is applied and the image forming apparatus equipped with the same. Will be omitted after having been described once by assigning the same reference numerals. In order to simplify the drawings and the description, even components that are to be represented in the drawings may be omitted as appropriate without being specifically described in the drawings. When a constituent element such as a published patent gazette is cited and explained as it is, the reference numeral is attached with parentheses to distinguish it from that of each embodiment.

  4 to 8 described later including FIGS. 1 to 3 and the like include examples of the sheet conveying apparatus to which the invention of the prior application is applied and an image forming apparatus equipped with the sheet conveying apparatus. explain in detail. First, an overall configuration of a copying machine 1 as an example of an image forming apparatus will be described with reference to FIG.

The copying machine 1 is a monochrome copying machine that reads an image from the surface of a document and forms a copy image on recording paper, transfer paper, paper, OHP film, etc. as various sheet-like recording media (hereinafter referred to as “sheets”). is there. The copying machine 1 includes an image forming apparatus main body 2 having an image forming unit that performs a predetermined image forming process based on a read original image, and the image forming apparatus main body 2 mounted thereon. As an example, a sheet feeding device 3 that supplies sheets S one by one, and a document reading device 4 that is mounted on the image forming apparatus main body 2 reads a document image and sends the document image information to the image forming apparatus main body 2. Have.
A paper discharge tray 9 is provided on the upper part of the image forming apparatus main body 2 so as to form a space below the document reading apparatus 4 and for stacking sheets that have passed through the image forming apparatus main body 2. A sheet conveying path R1 (hereinafter also referred to as “conveying path R1”) is formed as a sheet conveying path (sheet conveying path) for moving the sheet S from 3 to the paper discharge tray 9. Most of the transport path R1 extends from the sheet feeding device 3 to the upper part of the image forming apparatus main body 2, and extends in a substantially vertical upward direction, that is, a substantially vertical upward direction with respect to a substantially horizontal line, and the transport path R1. On the top, there are provided sheet conveying means as several sheet conveying means which are configured by a pair of conveying rollers, a pair of rollers, etc. with a predetermined interval corresponding to the minimum size sheet S. Any one of these sheet conveying means is configured to always convey the sheet S on the conveying path R1 by nipping or the like. Further, the sheet feeding device 3 is provided with a sheet conveying device 5 as a sheet conveying device for feeding and conveying the sheets S accommodated in the respective stages of the sheet feeding device 3 to the conveying path R1.

  In the image forming apparatus main body 2, a photosensitive unit 10 as an image forming unit for forming an image and a fixing device 11 are sequentially arranged from the upstream side to the downstream side of the conveyance path R <b> 1. After the photoreceptor unit 10 transfers the generated toner image to the sheet S conveyed from the upstream side to the downstream side on the conveyance path R1, the fixing device 11 transfers the transferred toner image. The sheet S fixed on the sheet S and fixed with the toner image is discharged to a sheet discharge tray 9 disposed at the end of the transport path R1.

The photoconductor unit 10 has a single drum-like photoconductor 10A as an image carrier, and can be rotated to a side plate (not shown) in the image forming apparatus main body 2 around a rotation shaft arranged substantially horizontally. It is supported by. The photoconductor 10A has a known configuration formed in a cylindrical shape with a predetermined diameter. The photosensitive member 10A is stabilized in the rotational direction indicated by an arrow in the drawing when a rotational driving force is transmitted from a driving source such as a motor provided on either the photosensitive unit 10 side or the image forming apparatus main body 2 side. It is driven to rotate at a constant speed.
Around the photoconductor 10A, a developing device 12, a transfer device 13, a photoconductor cleaning device 18, a static eliminator, and a charging device 14 are arranged in the rotation direction indicated by the arrows in the drawing. Within the range of one rotation in the counterclockwise rotation direction, the development position, the transfer position, the cleaning position, the charge removal position, and the charging position are sequentially applied from the upstream to the downstream by each of these devices 12 to 14, respectively. Is set.
Further, a latent image forming position is set between the charging position and the developing position, and exposure is performed to write an invisible latent image corresponding to image information by irradiating the latent image forming position with a predetermined laser beam. The device 47 is disposed obliquely below and slightly away from the photoconductor unit 10. Then, the photoconductor 10A is rotationally driven in a predetermined counterclockwise direction, and each of the devices 12 to 14 and the exposure device 47 perform a cooperative operation in a predetermined manner in synchronization with the rotation of the photoconductor 10A. Thus, a series of image forming processes are executed.

That is, the developing device 12 has an appropriate well-known configuration such as a developing roller that generates a toner brush in which toner particles are erected radially from the surface thereof, and is generated at a predetermined location on the surface of the photoreceptor 10A. The toner particles at the tip of the toner brush are attached to the latent image that moves around the circumference and passes through the developing position with the rotation of 10A, and the invisible latent image is visualized as a monochrome toner image.
The transfer device 13 includes two support rollers 15 and 16 that are opposed to each other with a predetermined spacing in a substantially vertical direction, and a transfer belt 17 that is an endless belt stretched between the support rollers 15 and 16. Then, the toner image on the outer peripheral surface of the photoreceptor 10A is transferred to the sheet S, and the sheet S on which the unfixed toner image is transferred is conveyed to the downstream side of the conveyance path R1. That is, the lower support roller 16 has its portion around which the transfer belt 17 is wound pressed against an approximately right diagonally lower portion of the photoconductor 10A, so that the transfer belt 17 is in contact with the surface of the photoconductor 10A and the transfer belt 17. The position is set. The upper support roller 15 is disposed in front of the introduction port of the fixing device 11.

The photoconductor cleaning device 18 is a blade material (not shown) configured such that the blade edge at the tip thereof is in contact with the cleaning position on the photoconductor 10A with a predetermined pressure, or the photoconductor is in contact with the cleaning position. It has one or both of the configurations of a rotating brush that rotates following the rotation of 10A, and removes toner, foreign matter, etc. remaining on the surface of the photoreceptor 10A after transfer.
The static eliminator is mainly composed of a lamp capable of emitting light of a predetermined intensity. The static elimination position is irradiated from this lamp to the static elimination position, and the charged state on the surface of the photoreceptor 10A passing through the static elimination position is determined. The surface potential of the photoconductor 10A after being released and passing through the transfer position is returned to the initial state.

The fixing device 11 includes a heating roller 31 having a built-in electric heater as a heat source, and a pressure roller 32 disposed to face the heating roller 31 in a substantially horizontal direction and pressed and urged toward the heating roller 31. When the heating roller 31 is rotationally driven by a driving source such as a motor (not shown), the pressure roller 32 in contact therewith is driven to rotate, and at a place where both the rollers 31 and 32 are in contact, a predetermined heating temperature is set. A nip portion for fixing the toner image on the sheet is formed by securing the applied pressure.
In the figure, reference numeral 20 denotes a toner storage container composed of a toner bottle or the like that stores new or new toner. A toner transport path (not shown) is formed from the toner storage container 20 to the developing device 12. When the developing device 12 consumes its own toner for development and becomes insufficient, new toner is replenished from the toner container 20 to the developing device 12.

  Below the image forming apparatus main body 2 is provided a paper feeding device 3 that can selectively select a paper size (sheet size) automatically or manually by a user according to the size of a document to be read. Yes. That is, the sheet feeding device 3 stores and arranges a plurality of sheet feeding trays 51 and 51 as sheet storing means in multiple stages in the sheet feeding device 3 and feeds each sheet feeding tray 51 and 51 individually. It is configured to be able to be pulled out of the apparatus 3, and the paper for the tray can be set in each paper feed tray 51 and an appropriate number of sheets can be replenished. Each of the paper feed trays 51 and 51 stores and stores a large number of sheets S having different sheet types (sheet types) in various vertical sizes and horizontal directions with respect to various sheet sizes and sheet conveyance directions (sheet conveyance directions). ing.

The document reading device 4 has a reading device main body 4A that forms the framework, and a contact glass 57 is disposed over a predetermined range on the upper surface of the reading device main body 4A. In the reading device main body 4A, reading means for optically reading a document image with a predetermined range on the surface of the contact glass 57 as a scanning target is housed. The reading means includes at least the first traveling body 53, the first traveling body 53, and the like. 2 is mainly composed of a traveling body 54, an imaging lens 55, and a reading sensor 56 such as a CCD.
In the document reading device 4, a document pressing plate 58 configured to be openable and closable between a closed position that covers the contact glass 57 and an open position that opens is provided on the upper surface of the reading device main body 4A. That is, the document pressing plate 58 is formed in a vertical and horizontal dimension larger than that of the contact glass 57, and one end of the original pressing plate 58 is supported on the upper surface of the reading apparatus main body 4A by a hinge (not shown) so as to be opened and closed.

  Based on the configuration described above, the operation of the copying machine 1 will be described. First, when copying a document with the copying machine 1, the user manually opens the document pressing plate 58 of the document reading device 4 from the closed position to the open position, and places and sets the document on the contact glass 57. The document pressing plate 58 is manually operated in the closing direction, and the document set on the contact glass 57 is pressed from above by the document pressing plate 58. By this operation, the original is brought into close contact with the contact glass 57 and spread in a flat shape so that the original surface can be read accurately, and the original is fixed on the glass 57.

  When the user depresses / turns on a start switch installed in an operation screen (not shown) provided in advance in the copying machine 1, the reading operation of the document reading device 4 is immediately started, and a drive mechanism (not shown) The first traveling body 53 and the second traveling body 54 are traveled. Then, the light from the light source of the first traveling body 53 is irradiated toward the document, the reflected light from the document surface is directed to the second traveling body 54, and the reflected light is reflected by the mirror of the second traveling body 54. The image is input to the reading sensor 56 through the imaging lens 55. As a result, the reading sensor 56 photoelectrically converts an image of the document and the like and reads it.

  When the start switch is turned on as described above, the photoconductor 10A of the photoconductor unit 10 starts rotating, and an operation for forming a toner image on the photoconductor 10A based on the read original image. Is started. That is, as the photoconductor 10A is rotated, predetermined portions on the outer peripheral surface of the photoconductor 10A are sequentially arranged between the charging device 14, the exposure device 47, the developing device 12, the transfer device 13, the photoconductor cleaning device 18, and the charge eliminating device. After passing through the respective positions set in step 1, the toner is sequentially charged to a predetermined charged state, a latent image is generated, visualized as a toner image, transferred to the paper S, and the residual toner is removed. The charging state is released, one cycle is completed, and the cycle is predetermined so that a toner image is generated in a predetermined length range of the outer peripheral surface in the rotation direction of the photoconductor 10A according to the image size to be formed. Persisted.

When the start switch is pressed, the operation of the sheet conveying device 5 attached to the sheet feeding stage from the sheet feeding tray 51 of the sheet feeding stage storing the automatically or manually selected sheet S in the sheet feeding apparatus 3 is operated. Thus, one sheet S is conveyed to the conveyance path R1 via a predetermined sheet conveyance path (sheet conveyance path). The sheet S is conveyed by a conveying roller or the like on the conveying path R1 in the image forming apparatus main body 2 substantially vertically upward, and the leading edge of the sheet S abuts against the registration roller pair 21 and temporarily stops.
On the other hand, in the case of manual paper feed, the paper S set on the manual feed tray 67 is first fed out by the rotation of the paper feed roller 67A for the manual feed tray, and when a plurality of paper S are stacked and set. The paper is separated into one sheet by the separation rollers 67B and 67C for the manual feed tray, conveyed to the manual sheet feed path R2, and further conveyed from the manual sheet feed path R2 to the conveyance path R1. Stops at 21.
Then, the registration roller pair 21 starts to rotate at an accurate timing according to the relative movement of the toner image on the photoconductor 10A that has been rotationally driven, and sends the temporarily stopped paper S to the transfer position. As a result, the toner image is transferred onto the paper S by the transfer device 13.

  The sheet S to which the unfixed monochrome toner image is transferred in this way is conveyed to the fixing device 11 by the transfer belt 17 of the transfer device 13 that forms a part of the conveying path R1, and passes through the nip portion formed by the fixing device 11. Then, predetermined heat and pressure are applied by the nip portion, whereby the image is fixed on the paper S. The sheet S on which the image is fixed is guided by the switching claw 34 toward the conveyance path R1 reaching the discharge tray 9 and is discharged onto the discharge tray 9 by the discharge rollers 35 to 38. Stacked. Then, the user can take out the paper stacked on the paper discharge tray 9 from the opening portion on the front side of the apparatus between the paper discharge tray 9 and the document reading device 4.

  Further, when the duplex copy mode is selected by the user's setting input, the sheet S on which the image is fixed on one side is conveyed to the sheet reversing device 42 side by the switching claw 34 and is arranged in the sheet reversing device 42. A plurality of pairs of rollers 66 and a guide member (not shown) are moved back and forth on the reverse conveyance path R3 to reverse the vertical direction of the paper surface, and then the resist is registered from a position positioned in front of the photosensitive unit 10. After returning to the conveyance path R1 via the roller pair 21, the sheet is conveyed on the conveyance path R1 and guided again to the transfer position. This time, after the image is transferred and fixed on the back surface of the sheet S, the discharge rollers 35 to 38 are used. The paper is finally discharged onto the paper discharge tray 9.

(First example)
Next, a characteristic configuration of the sheet conveying apparatus 5 (hereinafter also referred to as “first example”) to which the sheet conveying apparatus according to the invention of the prior application is applied will be described.
As shown in FIGS. 2 and 3, the sheet transport device 5 has a large number of sheets S stacked and accommodated in a predetermined tray (lower in this example) of the sheet feed tray 51 in the sheet feeder 3 shown in FIG. 1. One sheet S is pulled out from the sheet S, the sheet conveying direction (sheet conveying direction) of the drawn sheet S is changed, and the sheet S is fed to the image forming apparatus main body 2 substantially vertically above.

The sheet conveying device 5 is disposed on the downstream side of the first conveying unit (hereinafter referred to as “first conveying unit”) 6 that conveys the sheet S and the sheet conveying direction (sheet conveying direction) of the first conveying unit 6. A second transport means (hereinafter referred to as “second transport means”) 7 for transporting the paper S transported by the first transport means 6 in a paper transport direction different from the paper transport direction of the first transport means 6; It is mainly composed of a first conveyance path A as a sheet conveyance path (sheet conveyance path) formed between the first conveyance means 6 and the second conveyance means 7.
The sheet conveying device 5 is configured as a nipping / conveying means for nipping and conveying the sheet S by a pair of conveying rotation members with respect to the first conveying means 6 and the second conveying means 7. That is, the first conveying means 6 is configured as a first conveying rotating member pair composed of two conveying rotating members arranged opposite to each other, that is, a feed roller 61 and a reverse roller 62, and the second conveying means 7 includes a grip roller 81 and a roller. The second conveyance rotating member is constituted by a pair of conveying rotation members that are arranged opposite to each other with a conveying belt 82 stretched between a pulley 83 and a roller-shaped pulley 84. One of the pair is provided with a conveyance belt 82 that moves and guides (conveys) the paper S toward a clamping portion (nip portion), which will be described later, of the second conveyance means 7 while maintaining a state in contact with the leading edge of the paper S. The conveyance surface 82a which is the belt conveyance means 8 (movement guide means) and which is a belt running surface formed on the conveyance belt 82 in the belt conveyance means 8 is formed between the first conveyance means 6 and the second conveyance means 7. It is characterized in that it is positioned outside the first outer direction of the conveyance path A as the paper conveyance path formed (the sheet conveying path) to.

As described above, the paper conveyance direction of the first conveyance rotation member pair including the feed roller 61 and the reverse roller 62 and the paper conveyance direction of the second conveyance rotation member pair including the grip roller 81 and the conveyance belt 82 are: Different from each other, that is, the sheet conveying direction of the first conveying rotating member pair is set to a substantially horizontal direction which is an upper right diagonal direction in FIGS. 2 and 3, whereas the sheet conveying direction of the second conveying rotating member pair is The direction is set substantially vertically upward. Thus, the first conveyance path A formed between the first conveyance means 6 and the second conveyance means 7 is a curved curvature having a small curvature radius that causes the paper conveyance direction to change rapidly in the first conveyance path A. Forming part.
Here, the respective paper transport directions of the first and second transport means 6 and 7 are strictly expressed as follows. That is, in FIG. 4, the sheet conveying direction of the first conveying unit 6 includes the rotation center of the feed roller 61, the rotation center of the reverse roller 62, and the nipping portion of the feed roller 61 and the reverse roller 62 (hereinafter “nip portion”). It is set in a substantially horizontal direction perpendicular to the center of the nip portion in the line segment connecting the three points with the center.
Similarly, the sheet conveying direction of the second conveying means 7 is the rotation center of the grip roller 81, the rotation center of the pulley 83, and the clamping part (hereinafter also referred to as “nip part”) of the grip roller 81 and the conveying belt 82. It is set in a substantially vertical upward direction perpendicular to the center of the nip portion in the line segment connecting the three points with the center.

  In other words, in the sheet conveyance path formed between the first conveyance unit 6 and the second conveyance unit 7 and configured to change the sheet conveyance direction, the thickness direction of the sheet S that forms and conveys the sheet conveyance path Of the pair of facing surfaces that define the orientation of the sheet S, the surface on the side where the leading edge of the sheet S sent out from the first conveying means 6 abuts is at least the part where the leading edge of the sheet S abuts. A predetermined range up to the second conveying unit 7 is formed on the conveying guide surface that continuously and constantly moves in the direction approaching the clamping portion of the second conveying unit 7 over the longitudinal direction of the sheet conveying direction. The conveying guide surface is formed by a belt running surface (conveying surface 82a) formed on the conveying belt 82 in the belt conveying means 8. In addition, the range surrounded by the extension line along the paper conveyance direction of the first conveyance means 6 and the extension line along the paper conveyance direction of the second conveyance means 7 is an inner outline, and the other is the outer outline. The conveying surface 82a of the conveying belt 82 used for conveying the sheet formed by the flat belt running surface is disposed at a position deviated from the inner contour in the outer contour direction, and generally intersects the paper traveling direction. Has been extended to.

As shown in FIGS. 3 and 4, the belt conveying means 8 includes a conveying belt 82, a roller-like pulley 83 and a roller-like pulley as a pair of belt holding and rotating members that hold the conveying belt 82 so as to run. The pulley 84 is mainly comprised. Hereinafter, the “pulley 83” on the side facing the grip roller 81 and forming the nip portion with the conveying belt 82 interposed therebetween is the first belt holding and rotating member, and the “pulley 84” positioned upstream of the pulley 83 is the first. Also referred to as a belt holding and rotating member 2.
In the belt conveyance unit 8, the leading edge of the sheet S conveyed by the first conveyance unit 6 abuts on the conveyance surface 82 a of the conveyance belt 82 excluding the portion of the conveyance belt 82 held by the pulley 83 and the pulley 84. It is important to arrange them so that they are in contact. 4, the shaft center of the pulley 84 (the center of the pulley shaft 84a) is located above the lower end position of the reverse roller 62 and below the height of the downstream end of the conveyance guide member 71. By arranging the belt conveying means 8 in this manner, the leading edge of the paper S collides with the belly portion of the conveying belt 82 (the portion that should be called “effective conveying surface”), so that the conveying belt 82 is stabilized. An appropriate elastic displacement / deformation state can be obtained, and the leading edge of the sheet S can be reliably contacted with the conveying surface 82a of the conveying belt 82 (hereinafter also referred to as “belt conveying surface 82a”) without causing repulsion of the leading edge of the sheet S. The contact state is maintained, and the following effects can be obtained.
On the other hand, when the leading edge of the paper S is arranged so as to be in contact with (contact with) the conveyor belt 82 held by the pulley 83 and the pulley 84 of the conveyor belt 82, the conveyor belt 82 is connected to the pulley 83. The conveyor belt 82 portion held by the pulley 84 is generally harder than the belly portion of the conveyor belt 82 and is less elastically displaced and deformed. In this case, it is not preferable because it repels or a stable and appropriate elastic displacement / deformation state cannot be obtained. The same applies to each of the examples to which the invention of the prior application described later is applied, and the embodiments, modifications, examples, etc. to which the invention of the present application is applied (hereinafter also referred to simply as “the same”).

Further, as shown in FIG. 4, the belt conveying unit 8 causes the leading edge of the sheet S conveyed by the first conveying unit 6 to enter the conveying surface 82 a of the conveying belt 82 with an acute entry angle θ. It is also important to place them in By disposing the belt conveying means 8 in this way, the leading edge of the sheet S stably contacts the above-described antinode portion of the conveying belt 82, so that the leading edge of the sheet S reliably contacts the belt conveying surface 82a. This state is maintained, and the following effects can be obtained.
When the leading edge of the sheet S is arranged so as to enter the belt conveying surface 82a with a substantially perpendicular or right angle of incidence θ, the contact state of the leading end portion of the sheet S with the belt conveying surface 82a is unstable. For example, it is not preferable from the viewpoint of bending in the direction opposite to the traveling direction of the conveyor belt 82 or causing repulsion (the same applies hereinafter).

The paper feed trays 51 of each stage in the paper feed device 3 are formed in a substantially flat box shape having an upper opening, ensuring a planar shape capable of storing the maximum size paper S that can be handled by the copying machine 1. A bottom plate 50 as a sheet stacking unit is provided on the bottom surface. The bottom plate 50 is attached and fixed to a horizontal shaft 50A supported at the base end portion on the left side of FIG. The free end portion is configured to be swingable within the sheet feed tray 51 about the shaft 50A.
In addition, a recess having a predetermined shape is formed at the bottom of the paper feed tray 51, and the rising arm 52 is stored in the recess. The ascending arm 52 is fixed to a horizontal shaft 52A that is supported so that its base end is pivotable within the recess within a predetermined angular range, that is, is swingable, and the horizontal shaft 52A has a rotation (not shown). When the rotational driving force in an arbitrary rotational direction is transmitted from the driving source and rotated, the ascending arm 52 is driven to swing so as to occupy a predetermined tilted position about the horizontal shaft 52A. As a result, the free end portion of the raising arm 52 pushes up the bottom plate 50, and the one side periphery of the uppermost surface of the paper S placed on the bottom plate 50 is kept at a predetermined height position.

As described above, the paper feed tray 51 loads and stores the sheets S on the bottom plate 50 and raises the stacked sheets S by raising and tilting the free end portion on the right end side in the figure of the bottom plate 50. Even when the sheets S are fed one by one and the number of stacked sheets decreases, the uppermost surface is maintained at a predetermined height.
As described above, the paper feed tray 51 is configured to be attachable / detachable / removable with respect to the main body of the paper feeder 3. That is, the paper feed tray 51 is inserted into the main body of the paper feeding device 3 as shown in FIG. It is configured to be able to selectively occupy the separation position where the paper S can be replenished or the size of the paper S can be exchanged by being pulled out / removed to the front side. Further, at least the first transport unit 6, the second transport unit 7, and the paper transport path (transport path) arranged between the first transport unit 6 and the second transport unit 7 are when the paper feed tray 51 is pulled out. Left in the body. Therefore, in this example, it is an in-body paper discharge type image forming apparatus, but by providing the movement guide means, the paper can be transported along the transport path with the same curvature as the conventional one or less, so the width of the apparatus It is possible to prevent the advantage of the in-body discharge type from being diminished without increasing the direction.

The pickup roller 60 is rotatably supported by the housing 80 that forms the outer shape of the main body of the paper feeding device 3 so as to contact the uppermost surface of the paper S that has been raised to a predetermined height. A paper feed separation mechanism for separating and feeding the paper S into a single sheet is positioned on an extension line along the drawing direction of the paper S by the pickup roller 60. This paper feed separation mechanism is reverse to the feed roller 61. The roller 62 is configured to form a nip portion that is in contact with a predetermined pressure.
As shown in detail in FIG. 3, the pickup roller 60 is a well-known one that is integrally fixed around a shaft 60a that is integrally formed with a core metal (not shown), and is rotatable with the shaft 60a. A one-way clutch (not shown) is provided between the shaft 60a and the metal core, and is supported so as to rotate freely with respect to the shaft 60a when not driven. A soft high-friction material such as rubber having a high friction coefficient with respect to the paper S is used for the outer peripheral portion including the outer peripheral surface of the pickup roller 60 so that the pick-up roller 60 can be easily picked when contacting the paper S. In addition, on the outer peripheral surface portion of the pickup roller 60, there may be a case where a substantially saw-tooth shaped protrusion is formed on the entire circumference in order to increase the frictional resistance as appropriate.

  In this example, for example, an FRR (Feed Reverse Roller) paper feeding method, which is a reverse separation method, is adopted as a paper feeding method (sheet feeding method) that separates and feeds stacked paper S into one sheet without double feeding. is doing. That is, when two or more sheets S are pulled out by the pickup roller 60, the sheet S is separated into one sheet S in contact with the feed roller 61 and other sheets S in contact with the reverse roller 62, The feed roller 61 advances and feeds one sheet S as it is in the sheet conveying direction, while the reverse roller 62 advances another sheet in the direction opposite to the sheet conveying direction to return to the original stacked position. In addition, the reverse roller 62 is configured not to interfere with the sheet conveyance by the feed roller 61.

More specifically, the sheet feed separation mechanism using the FRR sheet feed method as the sheet separation mechanism is in contact with a feed roller 61 that is rotationally driven in a forward direction that advances in the sheet conveyance direction, and a lower side of the feed roller 61. , A reverse roller 62 that is driven in reverse by a rotational driving force transmitted in the reverse rotation direction via a torque limiter is provided, and the feed roller 61 is in contact with the uppermost sheet S on the bottom plate 50, The reverse roller 62 is in contact with the lower surface of the paper S in contact with the feed roller 61 regardless of whether two or more sheets are present.
The feed roller 61 is integrally fixed around a shaft 61a formed integrally with a core metal (not shown), and can be rotated together with the shaft 61a. Sometimes. In the outer peripheral portion including the outer peripheral surface of the feed roller 61, a rubber having a high coefficient of friction with respect to the paper S so that it can be easily sent out in the paper transport direction when it contacts the paper S, like the pickup roller 60. Such a soft high friction material is used. Also, the outer peripheral surface portion of the feed roller 61 may be formed with substantially saw-tooth shaped protrusions on the entire circumference in order to increase the frictional resistance as appropriate.
The reverse roller 62 is formed integrally with a metal core (not shown), and is rotatably supported by the housing 80 together with the reverse roller drive shaft 62a via the torque limiter.

In the FRR sheet feeding method, a weak torque in the reverse rotation direction with respect to the feed roller 61 is applied to the reverse roller 62 via a torque limiter (not shown). Accordingly, when the reverse roller 62 is in contact with the feed roller 61 or when one sheet S enters between the rollers 61 and 62, the reverse roller 62 rotates with the feed roller 61. That is, by the action of the torque limiter, for example, the reverse roller 62 slips with respect to the reverse roller drive shaft, and, similarly to the feed roller 61, the reverse roller 62 rotates in the forward direction that advances in the paper feeding direction. On the other hand, when the feed roller 61 is separated or when two or more sheets S enter between the rollers 61 and 62, the reverse roller 62 rotates in the reverse direction. For this reason, when the multi-feed paper S enters, other paper S in contact with the reverse roller 62 other than one paper S in contact with the feed roller 61 which is the uppermost paper S is upstream in the paper transport direction. Thus, the double feeding of the paper S is prevented.
Accordingly, the transport force supplied from the reverse roller 62 to the paper S that is in contact with the reverse roller 62 ensures that the transport force in the reverse direction is sufficient to return the paper S to the original stacking position. The conveying force supplied to the sheet S from the feed roller 61 for advancing S in the forward direction is set to a predetermined value so as not to prevent the sheet conveyance in the forward direction by the feed roller 61. For this reason, the so-called transport force supplied to the paper S from the feed roller 61 is reduced by the reverse transport force from the reverse roller 62.

  In the figure, reference numeral 65 denotes an idler gear coupled to a drive shaft that outputs a rotational driving force from a drive source provided on the main body side of the sheet feeding device 3, and the sheet feeding device is engaged by meshing between the gears or belt transmission. 3 is distributed and transmitted to the pickup roller 60 and the feed roller 61 so that the pickup roller 60 and the feed roller 61 are respectively rotated at a predetermined speed.

A grip roller 81 which is the other transport rotation member of the second transport rotation member pair in the second transport means 7 is disposed obliquely above the feed roller 61 via a rotation drive shaft 81 a formed integrally with the grip roller 81. The housing 80 is rotatably supported and arranged. The outer peripheral portion including the outer peripheral surface of the grip roller 81 also has a high coefficient of friction with respect to the paper S so that it can be easily sent out in the paper transport direction when it comes into contact with the paper S, like the feed roller 61. Soft high friction materials such as rubber are used.
In the vicinity of the grip roller 81, the pulley 83 is rotatably supported by the housing 80 so as to be in contact with the outer peripheral surface of the roller 81 via the conveying belt 82 and faces the grip roller 81 in the horizontal direction. Is arranged.
The pulley 83 is formed integrally with the pulley shaft 83a and is rotatably supported by the housing 80 together with the pulley shaft 83a. Below the pulley 83 diagonally to the left, the pulley 84 described above that is rotatably supported by the housing 80 is disposed. The pulley 84 is formed integrally with the pulley shaft 84a and is rotatably supported by the housing 80 together with the pulley shaft 84a. The pulleys 83 and 84 have a function as a belt holding and rotating member that supports the conveyor belt 82 so as to run and rotate. The pulley shafts 83a and 84a are each one continuous shaft, and are made of a metal such as iron, for example.

The arrangement of the belt conveying means 8 is not limited to the arrangement state described above, and may be as follows. That is, in FIG. 3, reference numeral 79 shown with parentheses indicates an open / close guide configured to be openable and closable with respect to the housing 80 as a part of the main body of the sheet conveying device 5. The opening / closing guide 79 is integrated (unitized) with a conveyance guide member 72 and a belt conveyance unit 8 to be described later, and is formed on the first conveyance path A or a vertical conveyance path extending substantially vertically upward. In order to make it easier for the user to handle jams, jams, etc., the conveyor belt 82 can be brought into and out of contact with the grip roller 81 around a hinge fulcrum shaft 76 (see FIG. 30 described later) below the housing 80. It is configured to be openable and closable.
When such an opening / closing guide 79 is provided, the pulley 83 and the pulley 84 are rotatably supported on the opening / closing guide 79 side together with the pulley shafts 83a and 84a.

Although the conveyance belt 82 is partially described above, it is an endless belt and is stretched between the pulleys 83 and 84. The distance between the shafts of the pulleys 83 and 84 is set in advance. The linear belt running surface (conveying surface 82 a) of the conveying belt 82 formed between the pulleys 83 and 84 is disposed at a position where the leading edge of the sheet S sent out by the first conveying means 6 always comes into contact. In this way, the outer peripheral surface of the conveyor belt 82 wound around the outer peripheral surface of the pulley 83 is in direct contact with the outer peripheral surface of the grip roller 81 with a predetermined pressure, and a clamping portion (nip portion) is formed at this contact portion. Has been. More specifically, a biasing means / elastic member (not shown) (for example, a spring 91 shown in FIGS. 10 and 21 described later) supports a pulley shaft 83a (not shown) a bearing member or a support member (for example, shown in FIG. 21 described later). By attaching the belt support member 86 to the grip roller 81, the conveyance belt 82 is urged in the direction in which it is pressed against the grip roller 81.
The conveyance belt 82 is formed of, for example, a rubber member that is an elastic member, and the surface thereof is made of a material of the belt itself or subjected to an appropriate surface treatment, and used on a sheet S (sheet) to be used. A predetermined coefficient of friction is set. That is, the conveyance belt 82 faces the sheet S and contacts the sheet surface, and the belt surface as the conveyance surface avoids a sliding contact between the sheet surface and the belt surface, so that the belt surface extends to the sheet surface. A coefficient of friction that can reliably transmit the conveyance driving force is set.

  Further, the conveyance belt 82 has a belt width in the sheet width direction orthogonal to the sheet conveyance direction, which is at least substantially the same as the maximum sheet width to be conveyed. That is, as the belt width of the conveying belt 82, at least a belt width equal to or larger than the maximum sheet width to be conveyed is set and secured. Similarly, the pulleys 83 and 84 on which the conveying belt 82 is stretched and the grip roller 81 facing and contacting the belt have pulleys and roller lengths in the paper width direction (axial longitudinal direction) longer than the belt width. Is formed. Therefore, the sheet S sent out from the first conveying means 6 always comes into contact with the conveying belt 82 over the entire width of the sheet, and the contact area between the two can be ensured as much as possible. Accordingly, the propulsive force supplied to the sheet S from the conveying belt 82 that is always moved in the sheet conveying direction, that is, the conveying propulsive force that advances the sheet S in the conveying direction, also has the maximum possible force from the conveying belt 82. It can be transmitted to the paper S.

A rotational driving source (not shown) such as an electric motor provided exclusively for rotational driving of the grip roller 81 is connected to the rotational driving shaft 81a of the grip roller 81 via a driving force transmission means such as a gear or a belt. (For example, see the drive mechanism 22 described later shown in FIGS. 17 and 18). The grip roller 81 is rotationally driven by transmitting a rotational driving force at a predetermined rotational speed from the rotational driving source via the driving force transmitting means. Thus, the grip roller 81 is a drive roller, while the conveyor belt 82 in contact with the grip roller 81 and the pulley 83 that supports the contact portion of the conveyor belt 82 from the inside of the belt are grips as a drive roller. A driven belt driven by a belt is driven by the rotation of the roller 81, and a driven roller is driven to rotate through the driven belt. Of course, the pulley 84 is also a driven roller that is rotationally driven via the driven belt.
If it is not necessary to have the same effect as that of the embodiments described later with reference to FIGS. 17 and 18, for example, the drive system for driving the grip roller 81 is removed from the drive mechanism 22 to remove the grip roller. 81 may be a driven side, and the conveyance belt 82 side may be driven by a drive mechanism (not shown).

2 and 3, reference numeral 70 denotes a conveyance guide member that is provided at a position on the inner side of the sheet conveyance device 5 and has a curved and fixed guide surface 70 a that protrudes substantially downward and contacts the sheet S. Reference numeral 71 denotes a conveyance guide member provided at a position on the outer side of the sheet conveyance device 5. The transport guide member 71 has a guide surface 71 a that is curved and fixed in a concave shape corresponding to the transport guide member 70, and is disposed facing the guide surface 70 a of the transport guide member 70 with a predetermined gap. . The conveyance guide members 70 and 71 are both fixed to the housing 80. Thus, the first conveying means 6 and the second conveying means 7 are constituted by the guide surface 70 a of the conveying guide member 70, the guide surface 71 a of the conveying guide member 71 facing the conveying guide member 70, and the conveying surface 82 a of the conveying belt 82. The 1st conveyance path A is formed between these.
2 and 3, 72 is a conveyance guide member provided at a position on the outer side of the vertical conveyance path approximately vertically upward from the second conveyance means 7, and 73 is a feed from the paper feed tray 51. This is a conveyance guide member that forms a sheet conveyance path to the nipping portion (nip portion) between the roller 61 and the reverse roller 62 and that has an introduction port for guiding and entering the sheet S in the nip portion. The conveyance guide member 70 is a curved surface that bulges substantially downward (on the conveyance guide member 71 side provided on the outer wall) across the line connecting the nip portions of the first conveyance means 6 and the second conveyance means 7. (Guide surface 70a) is provided, and the degree of bulge is set such that the sheet S is gently curved so that the leading edge of the sheet S always reaches the belt conveyance surface 82a.

  In FIG. 1, the upper apparatus configuration of the sheet feeding device 3 is an apparatus configured by conventional means. Compared with the lower apparatus configuration described above, the sheet conveyance apparatus 5 ′ replaced with the sheet conveyance apparatus 5. The only difference is the use of. The sheet conveying apparatus 5 ′ is different from the sheet conveying apparatus 5 only in that the second conveying means 7 ′ is used instead of the second conveying means 7. Compared with the second conveyance means 7, the second conveyance means 7 ′ has a grip roller 81 as a second conveyance rotation member pair and a roller that is driven and rotated (substantially the same size and shape as the pulley 83). Only) is different. In the upper paper feed tray 51 and the paper transport device 5 ′, plain paper or the like, which is the paper S having relatively low rigidity, is used except for the paper S (sheet) having relatively high rigidity such as thick paper and envelopes.

Next, a paper feeding operation from a predetermined stage in the paper feeding device 3 and a transporting operation of the paper transporting device 5 started in conjunction with the paper feeding operation will be described.
As shown in FIG. 2, the sheets S stacked on the bottom plate 50 are lifted so that the uppermost surface thereof has a predetermined height by the swinging and lifting operation of the lifting arm 52. The uppermost sheet S is pulled out and conveyed to a sheet feeding / separating mechanism including a feed roller 61 and a reverse roller 62. In the sheet feeding / separating mechanism, only the uppermost sheet is separated by the cooperative action of the feed roller 61 and the reverse roller 62, and the separated sheet S is moved to the downstream side of the sheet conveying path. 2 to 3, the leading edge of the sheet S is guided and moved by traveling in the arrow direction of the conveyance belt 82 while contacting the belt conveyance surface of the conveyance belt 82, and the grip roller 81 and the conveyance belt are moved. When reaching the nip portion 82, the paper S is nipped and conveyed by the grip roller 81 and the conveyance belt 82 and further conveyed vertically upward, and finally the paper S is sent out in a vertical posture.

More specifically, the leading edge of the sheet S that is nipped between the feed roller 61 and the reverse roller 62 and fed out from the nip portion first reaches the belt conveyance surface of the conveyance belt 82 as shown in FIG. And touch. Then, as shown in FIG. 3, the conveyance surface 82a is gradually curved from the leading end side of the sheet S as the conveyance surface 82a moves in the direction of the sheet conveyance due to the traveling of the conveyance belt 82 in the direction of arrow a, and this curve progresses. Accordingly, the contact area between the belt conveyance surface and the paper surface is enlarged. Therefore, even if the paper S is a highly rigid paper, a sufficient transport driving force for advancing the paper S in the transport direction from the belt transport surface to the paper surface can be applied. In this way, the belt conveyance means 8 provides a shortage from the conveyance resistance generated when the highly rigid paper S is curved and conveyed more deeply by the conveyance driving force applied from the first conveyance means 6. Give it to the paper S to make up for it. Therefore, it is possible to prevent at least the occurrence of defective conveyance of the paper S between the first and second conveying means 6 and 7 and to prevent the paper S from leading to the nip portion of the second conveying means 7. Can be reached.
On the other hand, since the conveyance surface 82a of the conveyance belt 81 continuously extends to the nip portion of the second conveyance means 7 as it is, the leading end portion of the sheet S that is in contact with the belt conveyance surface is reliably and smoothly stably pinched. Will be reached. In other words, first, even the highly rigid paper S is conveyed by the first conveying means 6 while being gently curved so that the leading edge always comes into contact with the belt conveying surface, and the leading edge of the paper S is the belt conveying surface. The leading edge of the sheet S is moved to the second sheet after the second sheet conveying propulsion force that advances in the sheet conveying direction from the belt conveying surface to the sheet S by the active conveying guide action by the belt conveying surface. The sheet S is bent more deeply so as to reach the holding portion of the conveying means 7.

  After the leading edge of the paper S reaches the second transport means 7 and the paper S is nipped and transported by the first transport means 6 and the second transport means 7, the transport means 6 and 7 are sufficient. Since a strong transport force acts on the paper S, the smooth transport of the highly rigid paper S can be continued. Further, even if the rear end of the sheet S is detached from the first conveying unit 6 and the conveying force from the first conveying unit 6 cannot be obtained, the holding portion of the second conveying unit 7 on the sheet S is moved to the rear end side. Depending on the contact state of the belt conveyance surface, the conveyance driving force is replenished from the belt conveyance surface to the paper surface again, and the degree of curvature of the paper S is gradually reduced, so that the paper conveyance can be continued. it can. As a result, as the paper transport device 5, the paper S received by the first transport means 6 is reliably and stably transferred from the second transport means 7 to the downstream paper transport path regardless of the rigidity of the paper S. Can be sent out.

As described above, the belt conveyance unit 8 is disposed in the outer direction of the first conveyance path A formed between the first conveyance unit 6 and the second conveyance unit 7 and maintains a state in contact with the leading edge of the paper S. However, it has a function as a movement guide means for moving and guiding the paper S toward the second transport means 7.
In this example, the belt conveying means 8 as the movement guiding means moves and guides the conveying direction of the sheet S in the direction toward the nipping portion (nip portion) of the second conveying means 7 by the conveying belt 82. It also has a function.

  Next, Reference Example 1 (hereinafter simply referred to as “Example 1”) according to the invention of the prior application will be described. The basic configuration and specifications are the same as those of the paper feeding device 3 having the paper conveying device 5 shown in FIGS. 1 to 3, and only a paper feeding device of “Imagio Neo453” manufactured by Ricoh Co., Ltd. is modified for testing. Machine (shown as “belt system” in Table 1) and a conventional paper conveying device (in FIGS. 1 to 3), the conveying rotating member facing the grip roller 81 is a roller-like pulley 83, and the conveying belt 82 and "Imagio" manufactured by Ricoh Co., Ltd., which is equipped with a paper feeder provided with a roller-like pulley 84 and having a paper feed device 5 'shown in the paper feeder 3 shown in FIG. Using a Neo453 "copying machine (shown as" conventional system "in Table 1), a comparative test on the paper feeding and conveying state (paper passing state) was conducted.

In the belt system, details of the belt conveying means 8 used in the comparative test and the main members around it (including the conventional system) are as follows.
Material of conveyor belt 82: Ethylene / propylene rubber (EPDM)
Conveyance belt 82 hardness: JIS K6253 A type 40 degrees Friction coefficient of conveyance belt 82 to paper: 2.6
Conveying belt 82 wall thickness: 1.5 mm
Pulley 83 diameter: 13 mm
Pulley 84 diameter: 7 mm
Spacing between pulleys 83 and 84: 13 mm (distance between pulley shafts 83a and 84a)
Expansion rate of the conveyor belt 82: 7%
Diameter of each roller 60, 61, 62, 81: All 20mm

  As a basic test condition, the weight of the paper (metric basis weight) is used as a substitute value for the strength of the paper (stiffness: stiffness). At a relative humidity of 50%, the sheets were fed from the same tray in the copying machine. Then, with the test conditions described below with reference to FIG. 4, a test for examining the variation (variation) in the conveyance time of each paper type was performed. FIG. 5 shows a test result of the variation in the conveyance time, and Table 1 shows a summary of the sheet passing state based on the test result of FIG.

  In FIG. 4, 88 is a paper feed sensor that detects the leading edge of the paper S picked up by the pickup roller 60, and 89 is a second conveying means 7 (belt system) or a grip roller 81 and a roller-like pulley 83. A vertical conveyance sensor for detecting the leading edge of a sheet conveyed by a pair (conventional method) is shown. The paper feed sensor 88 and the vertical conveyance sensor 89 are each composed of a reflective photosensor.

Further, the conveyance path length between the attachment / arrangement of the paper feed sensor 88 and the vertical conveyance sensor 89: the sheet conveyance distance (sheet conveyance distance) was set to a constant 57 mm for both the belt method and the conventional method as follows. That is, the conveyance path length from the arrangement portion of the paper feed sensor 88 to the nip portion of the feed roller 61 and the reverse roller 62 is 10 mm, and the nip portion of the second conveyance means 7 from the nip portion of the feed roller 61 and the reverse roller 62 ( Belt path), or the conveyance path length from the nip portion between the feed roller 61 and the reverse roller 62 to the nip portion between the grip roller 81 and the roller pulley 83 (conventional method) is the same 38 mm, The conveyance path length from the nip part (belt system) to the arrangement part of the vertical conveyance sensor 89 or from the nip part (conventional system) between the grip roller 81 and the roller pulley 83 to the arrangement part of the vertical conveyance sensor 89 is 9 mm. The total transport path length is 57 mm.
The radius of curvature at the center of the curved paper conveyance path (first conveyance path A) between the first conveyance means 6 and the second conveyance means 7 of the paper conveyance device 5 is constant about 20 mm in both the conventional method and the belt method. Carried out.

  In both the conventional method and the belt method, the pick-up pressure (feed pressure) by the pick-up roller 60 is changed to two types of 1.1N and 2.2N, and the driving-side feed roller 61 and the driving-side grip are changed. Both the linear speeds of the rollers 81 are the same 154 mm / s, and the arrival time of the leading edge of the paper transported through the transport path length 57 mm from the paper feed sensor 88 to the vertical transport sensor 89 is changed to five paper types, respectively. The graph of FIG. 5 shows the variation result of the paper type conveyance time measured by the oscilloscope.

From the test results shown in FIG. 5, when the metric basis weight is 256 g / m ² or more as the paper type, the conventional method has a large variation in conveyance time (long conveyance time) and a large slip of the paper. In the belt method, it was found that the variation in the conveyance time is small (the conveyance time is not so long) and the slip of the paper is small. Further, it was found that the conveyance force decreases when the pickup pressure is reduced, but in the case of the belt system of the present invention, even if the pickup pressure is reduced, the conveyance time is not significantly affected. Therefore, when the belt system of the present invention is adopted, the pickup pressure can be reduced, so that the power of the drive motor can be reduced. As a result, the apparatus can be reduced in size.

Next, Table 1 that summarizes the sheet passing state based on the test results of FIG. 5 will be described.
Here, “metric basis weight” corresponds to the weight of one sheet of paper per square meter in grams when displaying the weight of paper or paperboard (paper). In general, a paper having a small basis weight is “light paper” or “thin paper”, and a paper having a large basis weight is “heavy paper” or “thick paper”.
In the test results in Table 1, “good paper passing” indicated by a circle indicates that the paper feed sensor 88 was turned on and reached the vertical conveyance sensor 89 within a predetermined time after the leading edge of the paper (sheet) was detected. That is, “impossible to pass paper” indicated by a cross indicates that the conveyance is good means that the vertical conveyance sensor 89 is reached within a predetermined time after the paper feed sensor 88 is turned on and the leading edge of the paper is detected. This indicates that there was no conveyance, that is, a conveyance failure.

From the test results in Table 1, when the metric basis weight is 256 g / m ² or more as the paper type, the conventional method could not pass the paper, whereas the belt method according to the present invention shown in FIGS. All the papers passed. Thereby, the remarkable effect of the belt system according to the present invention was recognized.
According to the comparative observation of the paper passing / conveying situation, when the metric basis weight is 256 g / m ² or more in the conventional method, the paper becomes stiff and difficult to bend along the curved paper conveying path. 1 to 4, it was found that the leading edge of the sheet hits a roller-like pulley 83 that is in contact with the grip roller 81.
In addition, as a paper type, a paper having a metric basis weight of 256 g / m ² or more was subjected to a comparative observation of a sheet passing / conveying state using a paper whose surface portion was coated and a paper which was not coated. However, significant differences other than the test results in Table 1 were not recognized.

From the observation results of the paper conveyance process in Example 1 described above, the following was found. That is, when the highly rigid paper S having a metric basis weight of 256 g / m ² or more is conveyed from the first conveying means 6 to the belt conveying surface 82a of the belt conveying means 8 via the first conveying path A, the rigidity is increased. Therefore, the various guide members constituting the first transport path A are changed to simple shapes so as to reduce the transport load resistance, or various guide members are not required at all. It turns out that it is also possible.
Therefore, in the case of a sheet conveying apparatus that conveys using only the sheet S having relatively high rigidity, the essential components are the first conveying means 6, the second conveying means 7, the first and The second transport unit is disposed in the outer direction of the first transport path A (in this case, no guide member is formed) formed between the second transport units 6 and 7 and maintains a state in contact with the leading edge of the sheet S. Belt conveying means 8 (movement guiding means) for moving and guiding the paper S toward the paper 7.
From the above, the various guide members forming the first transport path A have relatively low rigidity, for example, when the paper S such as plain paper or PPC is transported, the straightness of the paper S with low rigidity is weak. It can be said that it is necessary to compensate for the straightness as compared with the paper S having relatively high rigidity such as thick paper, and to guide and guide it to the transport surface 82a of the transport belt 82. In other words, the first transport path A is formed in order to make the leading edge of the paper S abut on the belly portion of the belt transport surface 82a to compensate for the decrease in straightness as the rigidity of the paper S decreases. It can be said that it is necessary to set the shape of the guide surfaces of the various guide members.
In other words, as the sheet S having higher rigidity (the sheet S having a larger metric basis weight) is used, the various guides used when configuring the sheet conveyance path of the above-described curvature portion having a relatively small curvature radius. It becomes possible to give a degree of freedom to the design of the shape and arrangement of the members.
The material of the conveyor belt 82 is not limited to that used in the comparative test, and may be, for example, chloroprene rubber, urethane rubber, or silicon rubber. The rubber hardness of the conveyor belt 82 may be JIS K6253 A type 40 to 80 degrees.

  As described above, according to the paper conveyance device 5 and the copying machine 1 having the same shown in FIGS. 1 to 4, the paper type compatibility is achieved with a simple and low-cost device configuration while being compact and space-saving. It is possible to provide a sheet conveying apparatus and an image forming apparatus excellent in the above. In other words, basically, the conveyor belt is wound around the existing roller that constitutes the second conveying means, and the belt conveying means 8 is newly provided and added, and a dedicated drive source for the belt conveying means 8 is also provided. The sheet conveying device and the image forming apparatus can be realized at a low cost because of the extremely simple configuration.

  In the conventional configuration, the conveyance resistance due to the contact of the sheet with the conveyance guide member 70 is large, or the rigidity is high due to the conveyance load in the first conveyance path A from the first conveyance unit 6 to the second conveyance unit 7. In contrast to the paper type, which causes a conveyance failure, the paper conveyance device 5 can cope with a high-rigidity paper type and is a paper conveyance device with excellent paper type characteristics. That is, in the conventional configuration, since the fixing member is merely arranged for guiding the paper, the speed difference between the transported paper that is a moving body and the fixed guide member is fundamentally different. The sheet conveyance device 5 and the copying machine 1 not only eliminates the conveyance resistance but always eliminates the conveyance resistance and positively advances the sheet downstream. It is possible to guide while applying a conveyance driving force (or, by adding a conveyance force by the second conveyance means 7 to a conveyance force by the first conveyance means 6, the first conveyance means 6 to the second conveyance means 7 Since it is possible to counter the transport load in the first transport path A, the sheet can be advanced downstream). That is, in the paper transport device 5, the frictional resistance generated between the paper S and the transport belt 82 is not a resistance that hinders the transport of the paper S, but a negative resistance for applying a transport driving force to the paper S. Become. In other words, it is not converted to a resistance that acts to prevent the conveyance of the paper S, but is converted to a preferable negative resistance that acts to give a conveyance driving force to the paper S.

In addition, in the transport direction in which the paper S is transported, after the leading edge of the paper S abuts the running surface (transport surface) of the transport belt 82, the difference in the degree of rigidity depending on the paper type as the transport progresses. However, since the leading end surface of the sheet S is conveyed so as to gradually overlap the traveling surface of the conveying belt 82, the area of the sheet surface in contact with the belt traveling surface gradually increases. For this reason, as the contact area increases, the resistance force between the two can be increased, and a larger transport driving force for advancing the paper S in the transport direction can be supplied from the transport belt 82 to the paper S. As a result, the traveling direction of the sheet S is changed toward the nip portion between the grip roller 81 and the conveyance belt 82. In other words, the force acting as the conveyance driving force transmitted from the running surface (conveyance surface) of the conveyance belt 82 to the sheet surface is steadily increased.
Therefore, even if the rigidity of the paper S is high, the rigidity of the paper S is overcome, and the paper S is reliably deformed or curved in the thickness direction, and the paper S is surely directed toward the sandwiching portion of the second transporting unit downstream. Can be transported stably. As described above, since the main cause of the conveyance failure due to the high rigidity of the sheet S can be dealt with, the sheet conveyance after the leading edge of the sheet S reaches the clamping portion of the second conveying means is reliably and stably performed. It can last. As a result, the paper transport device can cope with a wide variety of paper types, the transport capability can be expanded, and high paper transport performance can be obtained.
(Second example)

  A second example to which the invention of the prior application is applied will be described with reference to FIGS. The same components and members as those of the sheet conveying device 5 shown in FIGS. 1 to 4 are denoted by the same reference numerals, and the description thereof is omitted or simplified. Although not particularly described, the configuration not described in this example, that is, the paper transport device and other configurations and their operations are the same as those of the paper transport device 5 of the first example shown in FIGS.

  6 to 8 is a first conveyance unit 5 formed between the first conveyance unit 6 and the second conveyance unit 7 as compared with the sheet conveyance device 5 illustrated in FIGS. In addition to the first conveyance path A serving as the sheet conveyance path, another independent second sheet conveyance path formed from the upstream of the second conveyance means 7 to the second conveyance means 7 and different from the first conveyance path A The point having the second transport path B as the first, the first transport path A and the second transport path B merge at the upstream of the second transport means 7 (hereinafter referred to as “joining transport path” or “joining section”) And the other belt conveying means 8 of the second conveyance rotating member pair is disposed so as to be out of the outline direction of the merged conveyance path of the first and second conveyance paths A and B. Mainly different. The sheet conveying device 5 shown in FIGS. 6 to 8 is the same as the sheet conveying device 5 of the first example and the first embodiment shown in FIGS. 1 to 4 except for the differences.

In other words, the belt conveying means 8 is configured such that one of the pair of roller-like pulleys 83, 84 around which the conveying belt 82 is stretched is separated from the pulley 83 by a predetermined distance to be freely rotatable to the housing 80. Thus, the belt conveyance surface 82a is formed as a surface of the second conveyance path B in the outline direction. Therefore, the leading surface of the sheet S conveyed on the first conveying path A by the first conveying means 6 always comes into contact with the conveying surface 82a of the conveying belt 82, and on the second conveying path B by an unillustrated conveying means. This prevents the conveyed paper S from reaching the second transport means 7.
The conveyance guide member 71 is different from that of the first example shown in FIGS. 1 to 4 only in that a vertical conveyance guide surface 71c is formed on the right side in the drawing. The conveyance guide member 72 is arranged in the outer direction of the second conveyance path B extending downward from the above-described vertical conveyance path as compared with that of the first example shown in FIGS. The only difference is that a longitudinal conveyance guide surface 72a for guiding the sheet S conveyed from the upstream side of B to the belt conveyance surface 82a is formed.
As described above, the second conveyance path B is formed by the vertical conveyance guide surface 71c of the conveyance guide member 71 and the vertical conveyance guide surface 72a of the conveyance guide member 72 that is opposed to the guide surface 71c and arranged with a predetermined opening interval. Is formed.

Next, the conveying operation of the sheet conveying device 5 shown in FIGS. 6 to 8 will be described. Since the paper S is fed out and transported from the state of being horizontally stacked in the paper feed tray 51, the paper transport direction in the paper feed separation mechanism of the first transport means 6 is substantially horizontal, but thereafter it is positioned upward. In order to convey the image forming apparatus main body 2 to the image forming unit, it is necessary to convey the sheet S in a substantially vertical upward direction orthogonal to the substantially horizontal direction.
Therefore, as shown in FIG. 7, after separation of the sheets S one by one by the sheet feeding / separating mechanism, one sheet S is conveyed with a gentle bend so that the conveyance resistance is small, and the leading end thereof is the conveyance belt. 82 abuts.
Since the conveyor belt 82 is traveling so as to travel in a substantially vertical upward (substantially above) direction indicated by an arrow a in FIG. 7, the leading edge of the sheet S that contacts the conveyor belt 82 is illustrated in FIG. As shown in FIG. 8, it is conveyed to the clamping part (nip part) between the grip roller 81 and the conveyor belt 82, and is clamped and conveyed downstream in the substantially vertical upward direction by the pair of the grip roller 81 and the conveyor belt 82. . At this time, as described above, the sheet S is subjected to the conveyance propulsion force that is transmitted from the conveyance belt 82 in the conveyance direction and acts toward the nip portion between the grip roller 81 and the conveyance belt 82 by the conveyance belt 82. Therefore, even the highly rigid paper S can be stably conveyed without causing a conveyance failure.

  As described above, according to the paper conveyance device 5 shown in FIGS. 6 to 8, the paper conveyance device having the merging conveyance path is the same as the paper conveyance device 5 described with reference to FIGS. 1 to 4. Effects, that is, high-stiffness paper such as cardboard can be stably conveyed, has excellent paper type compatibility, and has at least two or more conveyance paths such as first and second conveyance paths A and B. The paper conveying apparatus can be applied in correspondence with the developed paper conveying apparatus, and the application range can be expanded, that is, the paper conveying apparatus excellent in model compatibility can be obtained.

(Third example)
A third example to which the prior invention is applied will be described with reference to FIGS. In addition, the same code | symbol is attached | subjected to the component and member same as a 2nd example, and description is abbreviate | omitted or simplified. Although not particularly described, the configuration not described in the third example, that is, the paper transport device and other configurations and operations thereof are the same as those of the paper transport device 5 of the second example shown in FIGS.

As shown in FIGS. 9 to 13, the third example is different from the second example shown in FIGS. 6 to 8 in that the upper sheet conveying device 5 constituting the sheet feeding device 3 is supplied with the same feeding. The main difference is that the sheet conveying apparatus 5 is substantially the same as the lower sheet conveying apparatus 5 constituting the sheet apparatus 3. Another difference is that the transport belt 82 of the belt transport means 8 that is disposed downstream of the second transport means 7 in the upper paper transport apparatus 5 and constitutes the second transport means 7 of the upper paper transport apparatus 5 is different. A third conveyance path C as a sheet conveyance path (sheet conveyance path) formed along the diagonally upper left direction facing the conveyance surface 82a, and a conveyance path D as a double-sided refeed conveyance path or a manual feed conveyance path Is configured and defined so as to form a merging conveyance path that merges on the upstream side of the registration roller pair 21.
10 to 13, reference numeral 91 denotes an urging means in which one end is locked to the pulley shaft 83a and the other end is locked to an opening / closing guide 79 described later via a bearing 87 mounted on the pulley shaft 83a. As a spring. Due to the biasing force of the spring 91, the conveying belt 82 is constantly biased through the bearing 87, the pulley shaft 83 a, and the pulley 83 in such a direction as to contact and press contact with the outer peripheral surface of the grip roller 81. In FIG. 10, E indicated by a broken line indicates a manual paper feed conveyance path. The illustration of the manual paper feed conveyance path E is shown only in FIG. 10 for simplicity of the drawing, and is omitted in other drawings.

  As described above, the upper sheet transport device 5 is disposed on the downstream side in the sheet transport direction of the first transport unit 6 and the first transport unit 6 that transports the sheet S, and has been transported by the first transport unit 6. The paper conveyance direction of the paper S is different from the paper conveyance direction of the first conveyance means 6 (the paper conveyance direction of the first conveyance means 6 is set to a substantially horizontal direction directed obliquely upward to the right in the figure. On the other hand, the sheet conveying direction of the second conveying means 7 is set to be upward / downward / vertical upward), and between the first conveying means 6 and the second conveying means 7. The first conveyance path A formed in the first conveyance path A, the second conveyance path B formed from the upstream of the second conveyance means 7 to the second conveyance means 7 and different from the first conveyance path A, and the first conveyance path A And the second transport path B have a confluence transport path that joins on the upstream side of the second transport means 7, and the first transport path B Each of the feeding means 6 and the second conveying means 7 is configured as a nipping and conveying means for nipping and conveying the paper S. That is, the first conveying means 6 includes two opposing arrangements of a feed roller 61 and a reverse roller 62. The second conveying means 7 is configured as a first conveying rotating member pair, and the second conveying means 7 has a conveying belt stretched between a grip roller 81, a roller-like pulley 83 and a roller-like pulley 84. 82 is a configuration of a second transport rotating member pair composed of two transport rotating members disposed opposite to each other, and one of the second transport rotating member pairs is disposed in the outline direction of the merging transport path, This is a belt conveyance means 8 (movement guide means) provided with a conveyance belt 82 that moves and guides the sheet S toward the nip portion 99 as a holding portion of the second conveyance means 7 while maintaining the contact state. It is characterized in.

The conveyance path C is formed between an outer guide member 100 having a guide surface 100a for guiding paper and an inner guide member 101 having a guide surface 101a that faces the guide surface 100a and guides paper. The outer guide member 100 forming the transport path C is disposed so as to form a large space between the outer guide member 100 and the transport guide member 72 so that the paper can smoothly enter the transport path C.
As described above, the conveyance guide member 72 is connected to the second conveyance path B and is provided at a position on the outer side of the upward vertical conveyance path started from the second conveyance means 7. The open / close guide 79 is configured integrally with the transport guide member 72, the outer guide surface of the second transport path B, and the belt transport means 8 so that the paper can be easily removed when a paper jam or the like occurs. The hinge fulcrum shaft 76 of the housing 80, which is the main body, can be opened / closed in the direction of the arrow in the drawing (see FIG. 30 described later). When such an opening / closing guide 79 is provided, the pulley 83 and the pulley 84 are rotatably supported on the opening / closing guide 79 side together with the pulley shafts 83a and 84a.

Next, the conveyance operation of the paper conveyance device 5 of the third example will be described. The second example shown in FIGS. 6 to 8 until the sheet conveying operation shown in FIGS. 10 to 12, that is, until the leading edge of the sheet S is conveyed and sandwiched by the nip portion of the second conveying means 7. Since this operation is performed in the same manner as the operation of the paper conveying device 5, the description thereof is omitted.
As shown in FIG. 13, the sheet S conveyed downstream from the nip portion 99 of the second conveying means 7 by the conventional belt conveying means 8 is conveyed along the first conveying path A as its rigidity increases. The force to return from the deformed (buckled) state received at the time acts greatly, that is, acts greatly in the contour direction in which the conveying surface 82a of the conveying belt 82 of the belt conveying means 8 is arranged. For this reason, when the leading edge of the sheet S is conveyed along the conveying guide member 72 and further conveyed downstream toward the third conveying path C, the leading edge portion of the sheet S is in a state of being brazed and curved and deformed. The leading edge of the sheet S collides with the outer guide member 100 at an angle that is substantially perpendicular (substantially vertically above), causing a problem such as a jam due to slip at the collision of the guiding surface 100a and damage to the leading edge of the sheet S. May cause.
Further, as shown in FIG. 14, in order to reduce the above-described problem, a mylar 102 having elasticity is provided along the guide surface of the transport guide member 72 so as to extend downstream, thereby guiding the leading edge of the paper S. When measures are taken by increasing the amount, there is a problem that the rigidity of the Mylar 102 is increased due to the necessity of forcibly guiding the highly rigid paper S, leading to an increase in cost.

  Therefore, in the present invention, particularly when a relatively rigid sheet (sheet) such as a thick sheet is conveyed, the sheet is conveyed while being brought into contact with a guide member arranged on the downstream side of the second conveying unit with a strong contact pressure. In view of concerns about wear of the guide member, and in order to reduce the conveyance space for the purpose of downsizing the apparatus, when an elastic member such as Mylar is used as the guide member, to guide stiff paper In view of the disadvantage in terms of cost because it is necessary to use an elastic member having a higher elasticity, the sheet conveying direction conveyed by the second conveying unit is set downstream of the second conveying unit. By setting the sheet conveyance direction with a simple and low-cost configuration according to the layout of the image forming apparatus main body, the following embodiments and modifications are created to solve the above problems. .

(First embodiment)
With reference to FIG. 15, the sheet conveying device 5 </ b> A of the first embodiment will be described. In the first embodiment and the later-described embodiments and modifications, in order to solve the above-described problems described with reference to FIGS. 13 and 14, the basic configuration to be solved is used. In other words, the sheet conveying direction of the sheet conveyed by the second conveying unit can be changed to a direction facing the belt conveying surface in the belt conveying unit.

Hereinafter, a specific example of the sheet conveying device 5A of the first embodiment will be described. Compared with the sheet conveying apparatus 5 of the third example shown in FIGS. 10 to 12 and the like, the sheet conveying apparatus 5A of the first embodiment has a conveying belt 82 attached to the grip roller 81 as shown in FIG. The shaft center of the pulley 83 (the center of the pulley shaft 83a) of the belt transporting unit 8 that is opposed to the center of the grip roller 81 with respect to the shaft center of the grip roller 81 (the center of the rotational drive shaft 81a) The main difference is that it is shifted and displaced by the shift amount δ on the downstream side, that is, substantially vertically upward. The sheet conveying apparatus 5A is the same as the sheet conveying apparatus 5 of the third example except for the above differences.
In other words, the sheet conveying device 5A replaces the nip portion formed on a substantially horizontal plane connecting the center of the rotational drive shaft 81a of the grip roller 81 and the center of the pulley shaft 83a of the pulley 83 in each sheet conveying device 5. The center of the pulley shaft 83a of the pulley 83 is shifted and deviated by a shift amount δ from the center of the rotational drive shaft 81a of the grip roller 81 substantially vertically upward on the downstream side in the paper transport direction of the second transport means 7. As a result, the center of the nip 99 formed by the pressure contact between the grip roller 81 and the conveyor belt 82 is shifted and biased substantially vertically upward by a shift amount δ.

As described above, in the present embodiment, even when the paper S having relatively high rigidity such as thick paper and the front end portion of which is buckled / deformed is transported, the transport belt 82 is used. The leading edge of the paper S conveyed by the second conveying means 7 can smoothly enter the nip portion 99 of the second conveying means 7, and the paper conveying direction XA of the paper S conveyed by the second conveying means 7 (hereinafter referred to as “nip portion”). 99 ”(also referred to as“ 99 exit direction XA ”) can be changed to a diagonally upper left direction as indicated by a thick black arrow in the drawing, and therefore the guide surface of the outer guide member 100 disposed directly above the transport guide member 72 There are no problems such as 100a wear, jam due to paper slip, or damage to the leading edge of the paper S.
As a result, the leading edge of the sheet S is not conveyed along the conveyance guide member 72, and an elastic member such as the mylar 102 shown in FIG. 14 extends above the guide surface of the conveyance guide member 72. There is no need to provide it.
Since the direction and direction of the third transport path C vary from one image forming apparatus to another, it is preferable to set the shift amount δ according to the sheet transport path direction of each image forming apparatus.
In the above embodiment, the direction perpendicular to the center of the nip portion 99 in the line segment connecting the center of the rotational drive shaft 81a, the center of the pulley shaft 83a, and the center of the nip portion 99 is the sheet transport direction XA (nip) of the sheet S. Equal to the exit direction XA) of part 99. Therefore, with respect to the paper transport direction XA, the paper transport direction can be easily changed by determining the nip position of the pulley 83 so that the line connecting the rotation drive shaft 81a center and the pulley shaft 83a center is orthogonal. Further, the conveyance belt 82 has a horizontal line direction from the center of the rotation drive shaft 81a on the outer periphery of the grip roller 81, from a nip position located in a range connecting the center of the rotation drive shaft 81a and the center of the pulley shaft 83a on the outer periphery of the grip roller 81. It touches to the intersection.

  According to the shift method of the nip portion 99 according to the present embodiment, for example, with respect to the nip portion formed by pressure contact between the grip roller 81 and the roller-like pulley 83 as in the prior art, the pulley 83 is moved downstream in the sheet conveying direction. Compared with the case where the paper transport direction of the paper S transported downstream from the second transport means 7 is changed, the use of the transport belt 82 makes it easier for the paper S to enter the nip portion 99 and more smoothly. Feeding from the nip 99 is also a feature.

  As described above, according to the first embodiment, it is possible to provide the paper transport device 5A having a simple and low-cost configuration and excellent in paper type compatibility. The conventional configuration cannot cope with a high-rigidity paper type and causes a conveyance failure. In the present embodiment, however, the paper can cope with a high-rigidity paper type and has excellent paper type characteristics. The conveyance device 5A can be realized. In other words, the paper conveying device 5A also uses the belt conveying means 8 disposed in the outer direction of the merging / conveying path (merging portion) between the first conveying path A and the second conveying path B. The same basic functions and effects as those of the respective sheet conveying devices 5 are obtained.

In addition, since the paper conveyance direction on the downstream side of the belt conveyance unit 8 can be set according to the image forming apparatus as described above, the guide of the outer guide member 100 arranged just above the conveyance guide member 72. In addition to solving problems such as wear of the surface 100a, jamming due to paper slip, and damage to the leading edge of the paper S, it can also contribute to cost reduction.
Accordingly, even if the rigidity of the paper S is high, the rigidity of the paper S is overcome and the paper S is appropriately deformed or curved in the thickness direction, and the paper S is surely and stably directed toward the second conveying means 7 downstream. Can be transported. Thus, since the main cause of the conveyance failure due to the high rigidity of the sheet S can be dealt with, the sheet conveyance after the leading edge of the sheet S reaches the second conveying means 7 can be maintained reliably and stably. . As a result, the sheet conveying apparatus 5A can cope with a wide variety of paper types, can expand its conveying capacity, obtain high conveying performance, and save space and reduce the cost of the entire image forming apparatus. Can be achieved.

(Second Embodiment)
With reference to FIG. 16 to FIG. 18, a sheet conveying device 5 </ b> B of the second embodiment will be described. Compared with the sheet conveying apparatus 5 of the third example shown in FIGS. 10 to 12 and the like, the sheet conveying apparatus 5B includes, for example, a conventional pulley 83 that forms the nip 99 portion as shown in FIG. Instead of those made of relatively high hardness rubber, resin such as polyacetal resin, etc., it is composed and formed of, for example, urethane resin, urethane rubber (U), low hardness rubber, etc. as an elastic member, belt By using the belt conveying means 8B instead of the conveying means 8 and by directly contacting the conveying belt 82 side of the belt conveying means 8B with a grip roller 81 as a driving side as shown in FIGS. The main difference is that the driven side is clearly defined and limited.

  The second conveying means 7 of the paper conveying apparatus 5B is composed of a gripping roller 81 as a rotary conveying driving means / rotary conveying driving member capable of transmitting a driving force by rotating one of the opposed pairs of the nipping conveying means. The other of the opposing pair is arranged in the outer direction of the confluence conveyance path of the first conveyance path A and the second conveyance path B, and is in direct contact with the grip roller 81 and is in contact with the leading edge of the sheet S. The belt conveyance means 8B (movement guide means) including a conveyance belt 82 that conveys (moves and guides) the sheet S toward the nip portion 99 of the second conveyance means 7 while being held.

Further, the sheet conveying apparatus 5B of the first embodiment is longer than the maximum sheet width conveyed by the conveyance belt 82, as compared with the sheet conveying apparatus 5 shown in FIGS. In addition, instead of the configuration in which the lengths of the pulleys 83 and 84 and the grip roller 81 are continuously formed in the sheet width direction Y to be equal to or longer than the width of the conveying belt 82, the belt conveying means 8 is used. The sheet width direction Y of the conveyor belt 82 is intermittent in the sheet width direction Y so as to come into contact with a part of the leading edge (including the leading edge, the leading edge surface, and the corner / edge of the leading edge) of the sheet S in the sheet width direction Y. It is different in that it is structured.
In the present embodiment, like the paper transport device 5 shown in FIGS. 10 to 12 and the like, the width of the transport belt 82 is equal to or longer than the maximum paper width to be transported, and the pulley 83 , 84, and the length of the grip roller 81 may be configured continuously.

A plurality of grip rollers 81 are intermittently fixed and arranged on a rotational drive shaft 81a in the paper width direction Y in a skewered dumpling shape. On the other hand, the conveying belt 82 and the pulleys 83 and 84 of the belt conveying means 8B are disposed and arranged corresponding to at least one of the plurality of grip rollers 81 (that is, at least one of the opposed pairs). . Specifically, as shown in FIGS. 17 and 18, three grip rollers 81 are arranged on the rotation drive shaft 81 a, and three conveyance belts correspond to and face the three grip rollers 81. 82 is arranged with a width substantially equal to each grip roller 81. In the present embodiment, each of the three pulleys 83 and 84 is fixed to the pulley shafts 83a and 84a.
In FIG. 17, in order to clearly show the drive mechanism 22, the arrangement interval of the grip rollers 81 is intentionally shifted in the direction of the rotation drive shaft 81 a and is shown unevenly. Of course, it is arranged at intervals.

As shown in FIGS. 17 and 18, the drive mechanism 22 includes a paper feed motor 23 formed of a stepping motor as a single drive source / drive means, and a motor gear 24 fixed to the output shaft of the paper feed motor 23. The idler gear 25 meshed with the motor gear 24, the feed roller drive gear 61B meshed with the idler gear 25 and fixed to one end of the shaft 61a of the feed roller 61, the idler gear 26 meshed with the feed roller drive gear 61B, and the idler gear 26, and a feed roller gear 61A fixed to the other end of the shaft 61a near the feed roller 61, a feed roller gear 61A fixed to one end of the rotational drive shaft 81a of the grip roller 81, and the feed roller gear 61A. The above-described idler gear 65 that meshes with the roller gear 61A, and this Meshes with Idoragiya 65, is mainly composed of a pickup roller gear 60A which is fixed to the other end of the shaft 60a of the pickup roller 60 closer.
The paper feed motor 23 is fixed to the housing 80. The idler gears 25, 26, and 65 are rotatably supported by the housing 80, respectively.
As described above, in the present embodiment, the paper transport device 5B is compact and space-saving, that is, the first transport path A is configured with a curvature portion having a relatively small radius of curvature as illustrated in the first embodiment. Therefore, the sheet feeding motor 23 is single and serves as the driving means for the first conveying means 6 and the second conveying means 7 and contributes to the downsizing of the apparatus.

The reverse roller 62 is driven by a separate system, for example, equipped with a solenoid for releasing the pressure on the feed roller 61 and the like. In FIG. 17, 62b represents what was demonstrated as the torque limiter which is not shown in the example shown in FIGS.
In the example shown in FIGS. 1 to 4, the rotational drive relationship between the pickup roller 60 and the feed roller 61 has been simply described. In practice, however, as shown in an enlarged view in FIG. The shafts 60a and 61a are connected by the pickup arm member 64, and a solenoid (not shown) and the like are arranged so that the pickup roller 60 swings and displaces through the pickup arm member 64 around the shaft 61a on the feed roller 61 side. It is driven by a combination of springs.
In the actual drive mechanism 22, more drive force transmission members such as gears and timing belts are appropriately disposed between the paper feed motor 23 and the feed roller 61, but here the grip roller 81 is a rotation conveyance drive member. In order to clarify that this is the case, an example is shown in both figures.
Needless to say, the drive mechanism 22 can also be applied to the sheet conveying devices 5 and 5A shown in FIGS. 1 to 4 and FIGS. 7 to 13 and FIGS. It is. In addition, it should be noted that substantially the same drive mechanism 22 is used in the copying machine of the first embodiment described above.

According to the second embodiment, the pulley 83 on the side where the nip 99 is formed is formed of, for example, urethane resin, urethane rubber (U), low hardness rubber or the like as an elastic member, and the conveyor belt 82 side is By clarifying as the driven side, a large nip 99 can be formed between the gripping roller 81 facing the second conveying means 7 and the conveying belt 82 via the pulley 83, so that the conveying of the second conveying means 7 can be performed. The force can be increased, and the exit direction XA of the nip portion 99 can be set to the upper left direction in FIG.
In the second conveying means such as a conventional roller pair, when the configuration of this embodiment is simply used, the angle of entry of the leading edge of the paper into the nip portion becomes strict, and the leading edge of the paper becomes a roller on the nip portion forming side. It hits the stomach and tends to break the tip. On the other hand, according to this embodiment, since the conveyance belt 8 is used for one of the second conveyance means 7, the entry angle of the leading edge of the sheet S to the nip portion 99 is always kept constant. A stable approach to the nip 99 is possible. In addition, the leading edge of the sheet S conveyed from the first conveying unit 6 can absorb an impact when the paper S is first placed on the conveying belt 82. Further, since the trailing edge of the sheet S can pass through the top of the mountain of the conveyance guide member 71 and can be applied to the belt conveyance surface 82a, an impact sound (a so-called splash sound) can be absorbed. Can also be achieved.

Further, according to the second embodiment, the conveyor belt 82 of the belt conveyor 8B is pressed against the grip roller 81 that drives the pulley 83 by a biasing force of a spring (not shown), and is driven to rotate by the drive mechanism 22. Since the gripping roller 81 is in direct contact with the rotation and driven rotation, driving the gripping roller 81 side can reduce variations in the linear velocity of the conveying belt 82 rather than driving the conveying belt 82 side. . Thereby, by disposing the conveyor belt 82 rotating toward the sandwiching portion of the second conveyor unit 7 on the outer side (outer direction) of the turn of the first conveyance path A (paper conveyance path) and the outer circumference of the merging conveyance path, It is possible to improve the transportability of relatively stiff paper such as thick paper in the turn section of the first transport path A, and the grip roller 81 that faces and directly contacts the transport belt 82 is driven to rotate the transport belt 82. As a result, the sheet can be transported to the second transport means 7 and the subsequent parts at a stable linear velocity.
This advantage and effect can be easily understood by considering the following technical contents. That is, when the grip roller 81 is driven, the linear velocity of the grip roller 81 is determined only by the outer diameter and the rotational speed of the grip roller 81 itself. On the other hand, considering the case of driving the conveyor belt 82 side, when the conveyor belt 82 is driven, the conveyor belt 82 is driven by a roller-like pulley 83 (belt drive roller, main pulley) provided inside the conveyor belt 82. Is generally driven.
In this case, the linear velocity of the conveyor belt 82 is not limited to the outer diameter and the rotational speed of the pulley 83 provided inside the conveyor belt 82, but varies in the thickness of the conveyor belt 82 due to component variations and the thickness due to wear of the conveyor belt 82. It is influenced by the influence or slip between the conveyor belt 82 and the pulley 83. For this reason, driving the grip roller 81 side rather than driving the conveyor belt 82 side can reduce variations in the linear velocity of the conveyor belt 82.

(Third embodiment)
With reference to FIG. 19, a sheet conveying device 5 </ b> C of the third embodiment will be described. Compared with the sheet conveying apparatus 5 of the third example shown in FIGS. 10 to 12 and the like, the sheet conveying apparatus 5C is formed with a relatively low hardness rubber as shown in FIG. The main difference is that the conveyor belt 82 side of the belt conveyor means 8 is clearly defined as a driven side and directly limited to the grip roller 81 as a driving side.

  For example, ethylene / propylene rubber (EPDM) is used as the conveyance belt 82 formed of rubber having a relatively low hardness, and the base material (usually, the belt is made of rubber on a base material such as a cloth woven with fibers). The rubber hardness is JIS K6253 A type (JIS A scale), and it has a relatively low hardness range of 30-60 degrees. Yes. In addition to the above, for example, urethane rubber (U) or the like is also used as the material of the conveyor belt 82.

According to the third embodiment, according to the above configuration, the exit direction of the nip portion 99 can be set to the upper left oblique direction as in the second embodiment, and the same effect as in the second embodiment. Can be obtained.
Further, with the above configuration, the tension when the conveyor belt 82 is extended and used without being affected by mechanical strength, wear over time, and the like can be kept low, so that the rotational load on the driven side is kept small. You can also. Accordingly, it is possible to improve the followability to the grip roller 81 on the driving side as compared with the case where the tension of the conveying belt 82 is relatively high, and it is possible to stably convey the sheet at a set linear velocity. It becomes possible.

(Modification 1)
With reference to FIG. 20 to FIG. 24, a sheet transport device 5D according to Modification 1 to which the first embodiment and the like can be applied will be described. Except for the drive mechanism 22 of the sheet conveying devices 5B and 5C in the second and third embodiments shown in FIGS. 17 and 18, the third example shown in FIGS. 10 to 12, etc., and FIGS. In the first embodiment shown in FIG. 1, the conveyance belt 82 of each of the sheet conveyance devices 5 and 5A has a width of the conveyance belt 82 in the sheet width direction Y that is at least substantially the same as the width of the maximum size sheet to be conveyed, As the belt width of the conveyor belt 82, at least a belt width equal to or larger than the maximum sheet width to be conveyed is continuously set and secured. Similarly, the pulleys 83 and 84 over which the conveyance belt 82 is stretched and the grip roller 81 that is opposed to the conveyance belt 82 have pulleys and roller lengths in the paper width direction Y (axial longitudinal direction), and the belt width It is continuously formed to have a length equal to or longer than the length of. As a result, the sheet S sent out from the first conveying means 6 always comes into contact with the conveying belt 82 over the entire width of the sheet, and the contact area between the two can be ensured as much as possible. . Along with this, it is possible to transmit the maximum possible force for the conveyance propulsion force that advances the paper S that can be supplied to the paper S from the conveyance belt 82 that is always moved in the conveyance direction in the conveyance direction. Is listed as a feature. On the other hand, the first modification is configured as follows.

  The belt conveying means 8D of the paper conveying device 5D includes the paper conveying device 5 shown in FIGS. 10 to 12, the belt conveying means 8 of the paper conveying device 5A shown in FIG. 15, and the paper conveying device 5B shown in FIG. Compared to the belt conveying means 8B and the like, three pulleys 83 are rotatably supported on a pulley shaft 83b made of metal such as iron instead of the pulley 83 which is fixed on the pulley shaft 83a and is long in the axial direction. The pulleys 83 and 84 are made of a resin such as polyacetal resin, the belt support member 86 is used as a support member that rotatably supports the pulleys 83 and 84, and the shaft Instead of the pulley shaft 84a that is long and continuous in the direction, three pulley shafts 84b made of metal such as iron having a short length in the axial direction are used, and grips that are located on both outermost sides in the paper width direction Y Roller 81 21 (see FIG. 24, not shown in FIG. 21), and the outermost ends of the conveyor belt 82 and the pulleys 83, 84 of the belt conveyor means 8D arranged corresponding thereto are copying machines equipped with a sheet conveyor 5D. 1 is mainly different in that it is mounted and set to be smaller than the paper S of the minimum size (paper size in the paper width direction Y) used in 1.

  As shown in FIG. 4, the grip roller 81 and the conveyor belt 82 are in contact with each other on a line connecting the center of the rotation drive shaft 81a of the grip roller 81 and the center of the pulley shaft 83b, as shown in FIG. A sandwiching portion (nip portion) is formed at a portion including the contact point. The pulleys 83 and 84 are made of, for example, a resin such as a polyacetal resin having good lubrication performance and wear resistance / durability, and the weight is reduced.

Since the configuration of the conveyor belts 82 arranged at the three locations is the same, one of them will be described as a representative. For example, ethylene / propylene rubber (EPDM) as an elastic member is used as the material of the conveyor belt 82, and a base material (usually, the belt is often used to attach rubber to a base material such as a cloth woven with fibers). It is made of rubber without any material. In addition to the above, for example, urethane rubber (U) or the like is used as the material of the conveyor belt 82.
The conveyor belt 82 is rotated by the pulley shaft 84b and the pulley 83 rotatably supported by the pulley shaft 83b due to the assembly relationship of the pulleys 83 and 84 to the belt support member 86 via the pulley shafts 83b and 84b. It is suspended with a predetermined tension between the pulley 84 supported freely.
That is, the pulley shafts 83b and 84b are fixed and supported by the belt support member 86 so as to keep the distance between the shafts constant. At this time, the pulley shafts 83b and 84b are connected to the belt support member 86 so that the circumference of the conveyor belt 82 when the conveyor belt 82 is wound between the pulleys 83 and 84 is larger than the circumference of the conveyor belt 82 alone. It is also a feature point that it is arranged and supported in the case. With the above configuration, when the conveyor belt 82 is assembled on the belt support member 86 as the belt conveyor means 8D, the conveyor belt 82 is elastically adjusted so that the circumference after assembly is larger than the circumference of the conveyor belt 82 alone. It will be used by extending.

  Two bearings 87 are mounted on the pulley shaft 83 b between the three belt support members 86. A spring 91 (compression spring) as an urging means (or an urging member / elastic member) pressurizes the pulley shaft 83b via a bearing 87 to generate a conveying force for conveying the paper. As described above, the pulley shaft 83b and the pulley shaft 84b are fixed by the belt support member 86 so as to maintain a constant distance between the shafts, and the pulley shaft 84b is configured to be swingable about the pulley shaft 83b. ing.

The belt support member 86 is integrally formed of a resin such as polyacetal resin, and the weight is reduced. A spring pedestal 86 a that engages one end of the spring 92 is integrally formed on the back wall of the belt support member 86. Retaining rings for preventing the pulley shafts 83b and 84b from coming off are mounted in the vicinity of the pulley shafts 83b and 84b protruding from the belt support member 86.
As shown in FIG. 21, the back surface of the belt support member 86 is urged between the spring base 86a of the belt support member 86 and the spring receiving member 93 fixed to the open / close guide 79, thereby conveying the belt 82. 21 is mounted with a spring (compression spring) 92 as a biasing means (or a biasing member / elastic member) that always biases the gripping roller 81 in a direction in which it is pressed against the grip roller 81 shown in FIG.

  As shown by hatching in FIG. 22, a positioning portion 86b for positioning the transport belt 82 at a predetermined position is integrally formed at the lower portion of the belt support member 86, and the positioning portion 86b is transported. By contacting the guide member 72, the position of the conveyance belt 82 itself is positioned. Further, as shown in FIGS. 21 and 24, the positioning portion 86b and the conveyance guide member 72 are brought into contact with each other by the biasing force of the spring 92, whereby the conveyance belt 82 is positioned at a predetermined position. A belt protruding amount h from the conveyance guide rib 72b formed to protrude inward is ensured.

As shown in detail in FIG. 24, a U-shaped groove 87a is formed in the bearing 87, and the pulley shaft 83b is loosely fitted to the U-shaped groove 87a, so that the pulley shaft 83b is urged by the urging force of the spring 91. The conveying belt 82 is urged and pressurized in a direction in which the conveying belt 82 is pressed against the grip roller 81. The position of the pulley shaft 83b is fixed when the conveying belt 82 is in pressure contact with the grip roller 81, but the pulley shaft 84b is configured to be swingable in the direction of the arrow shown in FIG. 22 about the pulley shaft 83b. .
21 and 24, it has been described above that one end of the spring 92 presses the belt support member 86, but the other end is supported and locked by the spring pressurizing table 94. The spring pressing base 94 is configured to be movable and fixed at an arbitrary position with respect to a slit 93a formed in the spring receiving member 93 along the direction of the urging force of the spring 92. In the figure, an example of fastening and fixing with screws is shown. With this configuration, the spring load as an urging force of the spring 92, that is, the applied pressure can be changed by arbitrarily changing the compression length of the spring 92 at three locations. In this modification, the spring specifications such as the spring load, spring length, and shape of the two springs 91 are the same. Similarly, the same spring specifications such as spring load, spring length, and shape of the three springs 92 are used.

  As described above, the conveying belt 82 of the belt conveying means 8D in the present modification has a pair of roller-like pulleys due to the assembly relationship of the pulleys 83 and 84 to the belt support member 86 via the pulley shafts 83b and 84b. It is spanned between 83 and 84 with a predetermined tension. The conveyor belt 82 is pressed against a grip roller 81 driven by a pulley 83 provided to be freely rotatable by an urging force of a spring 92, and is driven and rotated as the grip roller 81 rotates. .

Therefore, according to the modified example 1, the following advantages and effects are achieved. First, since the belt conveying means 8D is configured intermittently, the cost can be reduced compared to the long belt conveying means 8.
Secondly, the conveyance belt 82 of the belt conveyance means 8D is configured to be brought into direct contact with the grip roller 81 (rotational conveyance drive member) that is rotationally driven by the drive mechanism 22, and therefore drives the conveyance belt 82 side. The variation in the linear velocity of the conveyor belt 82 can be reduced by driving the grip roller 81 side rather than the case. Thereby, the conveyance which rotates and travels toward the clamping part of the 2nd conveyance means 7 on the outer side (outer direction) of the turn of the confluence conveyance path of the 1st conveyance path A (paper conveyance path) and the 2nd paper conveyance path B By disposing the belt 82, it is possible to improve the paper conveyance performance of relatively high rigidity such as thick paper in the turn portion of the first conveyance path A, and the grip roller 81 that directly faces and contacts the conveyance belt 82 is driven. By rotating the conveying belt 82, the sheet can be conveyed to the second conveying means 7 and the subsequent line at a stable linear velocity. The advantages and effects are the same as described with reference to the drive mechanism 22 of FIGS.

Third, the pulleys 83 and 84 (belt holding and rotating members) are pivotally supported by a belt support member 86 (support member) so as to keep the distance between the shafts constant. The pulley shafts 83b and 84b of the pulleys 83 and 84 are attached to the belt support member 86 so that the circumference of the conveyor belt 82 when the conveyor belt 82 made of an elastic member is wound is larger than the circumference of the conveyor belt 82 alone. With this arrangement, in this embodiment, as a means for applying a tension to the belt, a mechanism for applying a tension to a belt called a commonly used tie toner is not provided, and the conveying belt 82 is elastically provided between the two-shaft pulleys 83 and 84. Because it has a structure that stretches and tensions it, it is simpler, saves space, and costs less than the conventional structure that provides a mechanism such as Tightener. It can be.
As a result, the mechanism is simple, space-saving, and cost-saving in the paper transport device that can improve the paper transport performance of relatively high rigidity such as thick paper in the turn section of the first transport path A in the confluence transport path. Can be realized.
By adding the above-described unique configuration of each of the sheet conveying apparatuses 5A, 5B, and 5C of the first to third embodiments to the modification 1 that exhibits the above-described effects, the functions and effects of the modification 1 are also obtained. Of course, it can be configured to play.

(Fourth embodiment)
With reference to FIGS. 25 to 28, a sheet conveying device 5E according to the fourth embodiment will be described. The paper conveying device 5E is divided into a plurality (three in this embodiment) in the paper width direction Y and independent of the belt conveying means 8D of the paper conveying device 5D shown in FIGS. Thus, the main difference is that the belt conveying means 8E configured to run and rotate is used. The paper transport device 5E is the same as the paper transport device 5D except for the above differences.

In the sheet conveying device 5E, the three conveying belts 82 are configured to travel independently of each other, with three sets of belt conveying means 8E and a shaft that loosely supports the pulley shaft 83c of the pulley 83 of each belt conveying means 8E. By urging the support member 90 and the back surface of the belt support member 96 constituting each belt conveying means 8E, each conveyance belt 82 is urged so as to always contact the grip roller 81 shown in FIGS. It is mainly composed of a spring (compression spring) 97 as an urging means (or an urging member / elastic member).
Compared with the belt conveying means 8D shown in FIGS. 20 to 24, the belt conveying means 8E is replaced with a common pulley shaft 83b which is long and continuous in the axial direction, as shown in FIGS. Instead of the belt support member 86, a belt support member 96 that fixes and supports the pulley shafts 83 c and 84 b is used instead of the belt support member 86. Belt pulleys 83c of the pulley 83 on the side where the nip portion 99 'is formed in the belt conveyance means 8E arranged on the center side in the paper width direction Y and the belt conveyance means arranged on both sides in the paper width direction Y. 8E is mainly different from the pulley shaft 83c of the pulley 83 on the side where the nip portion 99 is formed in that it is biased toward the downstream side in the sheet conveying direction of the second conveying means 7, in other words, shifted.

  The belt support member 96 is integrally formed of, for example, a resin such as polyacetal resin having good lubrication performance, wear resistance, and durability, so that weight reduction is achieved. A spring pedestal 96 a that engages one end of the spring 97 is integrally formed on the back wall of the belt support member 96. In the vicinity of the six pulley shafts 84b protruding from the belt support member 96, retaining rings (not shown) for preventing the pulley shaft 84b from coming off are mounted.

The shaft support member 90 is integrally formed of an appropriate resin, metal, or the like having a predetermined strength, and is fixed to the back wall of the conveyance guide member 72. The shaft support member 90 is formed with a total of six elongated support holes 90a that slidably support both ends of the pulley shaft 83c of each belt conveying means 8E. Each support hole 90a is formed so that its inner diameter in the height direction is slightly larger than the outer diameter of the pulley shaft 83c, so that the pulley shaft 83c is loosely fitted (freely fitted).
Further, as shown in FIGS. 27 and 28, each support hole 90a is formed on the center side in the paper width direction Y, and is substantially vertically higher than that formed on both sides in the paper width direction Y. It is formed to be biased and shifted in the direction by the dimension ha. As a result, the pulley shaft 83c of the pulley 83 on the side where the nip portion 99 ′ is formed in the belt conveying means 8E arranged on the center side in the paper width direction Y is the belt conveying means 8E arranged on both sides in the paper width direction Y. In this case, the second support means 7 is loosely supported by the support holes 90a in a state of being shifted to the downstream side in the paper transport direction of the second transport means 7 from the pulley shaft 83c of the pulley 83 on the side where the nip 99 is formed. As a result, as shown in FIGS. 25 and 26, the conveyance belt 82 disposed on the center side in the sheet width direction Y is substantially the same as the dimension ha as compared with that disposed on both sides in the sheet width direction Y. It will be displaced and shifted vertically upward.
The pulley shaft 83c is formed so as to protrude outwardly from the support hole 90a of the shaft support member 90, and retaining rings (not shown) for preventing the pulley shaft 83c from coming off are mounted in the vicinity of the six pulley shafts 83c. May be.

The spring 97 is mounted between the inner wall surface of the shaft support member 90 that supports each belt conveyance means 8E and the spring base 96a of the belt support member 96, and the conveyance belt 82 is connected to the grip roller via the belt support member 96. It is energized in a direction that always contacts 81. In the example of this embodiment, the same spring specifications such as the spring load, spring length, and shape of the spring 97 are used.
The three sets of belt conveying means 8E are configured and assembled from the common components described above. Incidentally, the shape of each component is set so that the three belt conveying surfaces 82a belong to substantially the same plane in a state where each belt conveying means 8E is urged by each spring 97 after being attached to the shaft support member 90. Has been.

As described above, according to the present embodiment, first, the conveyance belts 82 of the three sets of belt conveyance means 8E can be independently driven and rotated by the rotation of the grip roller 81. Therefore, the belt width of the conveyance belt 82 of each belt conveyance means 8E can be reduced, and the influence of the thickness deviation in the belt width direction can be reduced, so that stable paper conveyance can be realized.
Further, as shown in FIGS. 25 to 28, the conveyance belt 82 disposed on the center side in the paper width direction Y is substantially equal to the dimension ha as compared with those disposed on both sides in the paper width direction Y. As shown in FIGS. 25 and 26, the paper S is relatively stiff, such as thick paper, and its leading end portion is buckled / deformed as a result of being arranged in a vertically upward direction. Even when transporting S, the leading edge of the sheet S transported by the transport belt 82 can smoothly enter the nip portions 99 and 99 ′ of the second transport unit 7. Since the exit direction XA of the nip portion of the conveyed paper S can be changed to the upper left direction as indicated by the thick black arrow in the figure, the outer guide member 100 disposed directly above the transport guide member 72. Wear of the guide surface 100a, Inconveniences such as jam due to paper slip or damage to the leading edge of the paper S do not occur.
As a result, the leading edge of the sheet S is not conveyed along the conveyance guide member 72, and an elastic member such as the mylar 102 shown in FIG. 14 extends above the guide surface of the conveyance guide member 72. There is no need to provide it.
Further, as shown in FIG. 26, when the trailing edge of the sheet S passes through the nip portions 99 and 99 ′, the sheet S first comes out of the nip portion 99 formed by the conveying belts 82 arranged on both sides in the sheet width direction Y. The trailing edge of the sheet S is moved to the downstream end portion (upper end portion in the drawing) of the conveying guide member 72 by passing through the nip portion 99 ′ formed by the conveying belt 82 disposed on the center side in the sheet width direction Y. Since the contact timing can be shifted in the sheet width direction Y (soft landing), the trailing sound of the trailing edge of the sheet S due to the trailing edge of the sheet S abutting against the downstream end of the transport guide member 72 is shocked. Can be reduced.

  Although partly described above, as shown in FIGS. 30A and 30B, the configuration on the main body side of the sheet feeding device 3 is divided into the second conveyance path B, as in a general conventional sheet feeding device. Then, with respect to the apparatus main body 78 provided with the housing 80 and the like of the first embodiment shown in FIG. A configuration that can be opened and closed in the directions of arrows C and D in FIG. 25 is employed. With such an open / close configuration, the jammed paper (jam paper) can be easily removed. The opening / closing guide 79 functions as an opening / closing unit configured by integrating the belt conveying means 8 and the conveying guide member 72.

(Fifth embodiment)
With reference to FIGS. 31 and 32, a fifth embodiment of the present invention will be described.
The fifth embodiment shown in FIGS. 31 and 32 only uses a paper conveyance device 5F instead of the paper conveyance device 5D, as compared with the paper conveyance device 5D of the first modification shown in FIGS. Is different. The configuration of the fifth embodiment other than the differences is the same as that of the copier 1 shown in FIG. 9 provided with the sheet conveying device 5D of the first modification.
The sheet conveying device 5F of the fifth embodiment is replaced with a pulley shaft 83b of the belt conveying means 8D, as shown in FIG. 31, as compared with the sheet conveying device 5D of Modification 1 shown in FIGS. Thus, as described later, a belt conveying means 8F having a pulley shaft 83d configured to be movable is used. If necessary, specifically, depending on the paper type (sheet type), the pulley shaft of the pulley 83 is used. 32 d is mainly different from the second conveyance unit 7 in that it includes a displacement unit 109 that displaces the second conveyance unit 7 downstream in the sheet conveyance direction, and a control unit 43 that controls the displacement unit 109.

  The displacement means 109 is supported so as to be rotatable within a predetermined angle range, that is, swingable around a rotation shaft 111 planted on the opening / closing guide side (not shown), and one end thereof is in contact with the lower end of the pulley shaft 83d. The arm-shaped link 110 to be engaged, the connecting bar 113 whose one end is loosely connected to the other end of the link 110 via the support shaft 112, and the plunger 115a is connected to the other end of the connecting bar 113 via a pin. One end of the link 110 is stretched between a solenoid 115 as a driving means loosely connected to the end, and the other end of the link 110 and a pin (not shown) disposed on the opening / closing guide (not shown). It is mainly composed of a spring 114 (tensile spring) as an urging means (or an urging member / elastic member) that constantly urges the portion in the direction of swinging clockwise in the drawing.

The belt conveying means 8F is replaced with a pulley shaft 83b when described with reference to FIGS. 21 to 24, instead of the configuration in which the belt support member 86 is held at a predetermined distance between the shafts as compared with the belt conveying means 8D. Only the pulley shaft 83d is supported so as to be movable by substantially the same member as the belt support member 86. Specifically, the pulley shaft 83d is moved downstream of the second conveying means 7 in the sheet conveying direction by the biasing force of the spring 91. It is supported by a member substantially the same as a belt support member 86 formed with a hole (not shown) having a substantially arcuate locus that rolls on the outer peripheral surface of the grip roller 81 via the conveyor belt 82 so as to be displaceable. The main difference is. In the belt conveying means 8F, the pulley shaft 84b on the pulley 84 side facing the pulley shaft 83d is composed of one continuous shaft so as to rotatably support the three pulleys 84, as shown in FIGS. The belt support member 86 shown is fixed and supported so as not to move. Configurations other than the above-described differences, that is, a plurality of belt conveying means 8F (the same three as described above in the present embodiment) are arranged in the paper width direction, and the pulley shaft 83d is 1 similarly to the pulley shaft 83b. The point that it is a continuous shaft of the book, the point that the pulleys 83 and 84 are urged by the springs 91 and 92, the material of the above-mentioned components constituting the belt conveying means 8F, etc. are the same as the belt conveying means 8D. is there.
One link 110 is provided for each of the belt conveying means 8F arranged on the front side of the paper and the belt conveying means 8F arranged on the back side, and the links 110 on both sides are connected and fixed by the support shaft 111. By doing so, the pulley shaft 83d may be displaced more stably.

Since the conveying belt 82 of the belt conveying means 8F changes from a predetermined inter-axis distance occupying the initial position to a direction in which the inter-axis distance becomes longer by occupying the biased position by an operation described later of the displacing means 109. The stretch rate (%) of the conveyor belt 82 is set to 10 to 5% so that the rotational load when the belt 82 is driven to rotate is suppressed as much as possible, and the linear velocity of the conveyor belt 82 is substantially the same as that of the grip roller 81. It is preferable to suppress the elongation due to the change in the inter-axis distance so as to be within the range of
A test was conducted to set necessary threshold values for the stretch ratio of the conveyor belt 82 and the hardness of the rubber under the condition that the thickness of the conveyor belt 82 was constant. That is, as a necessary threshold value / evaluation standard, it means that the linear velocity of the conveying belt 82 is substantially the same as the linear velocity of the grip roller 81, in other words, the intended linear velocity of the conveying belt 82 can be obtained. To do.
Using the above threshold as a reference, an evaluation test as to whether or not the combination of each parameter of the stretch ratio of the conveyor belt 82 and the rubber (EPDM) hardness is suitable for holding and stable conveyance of paper (sheet) is performed. went. As test conditions, the distance between the shafts was constant at 13 mm, the thickness of the conveyor belt 82 was constant at 1.5 mm in a room temperature environment, and the hardness of the rubber of the conveyor belt 82 (JIS K 6253 A type) was 40 °, 60 °. , And changed in three stages of 80 °. As a result of carrying out under the same conditions as in Example 1 except for the test conditions described above, the range of the stretch rate (%) in the range of 10 to 5% when the hardness is 40 °, and the stretch rate (%) when the hardness is 60 °. When the hardness is 80 °, the elongation ratio (%) is 5%, which is a preferable combination range. Accordingly, it is important that the amount of change in the inter-axis distance between the pulley shafts 83d and 84b is within the above-described preferable combination range.

In other words, the displacement means 109 moves the pulley shaft 83d of the pulley 83 in the belt conveying means 8F from the initial position, which is also the first position shown in FIG. It is displaced between a biased position which is also a second position biased to the downstream side of the sheet conveying direction of the means 7. Here, the biased position means, for example, a position where the pulley 83 occupies the state of FIG.
In a state where the belt conveying means 8F occupies the home position, the pulley shaft 83d is positioned below the home position shown in FIG. 31 due to the substantially same member configuration as the belt support member 86 shown in FIGS. It is supported not to move.

  The solenoid 115 is formed of, for example, a pull-type DC solenoid, and is fixed to an immobile member of an opening / closing guide (not shown). When power is supplied to the solenoid 115 and the solenoid 115 is turned on, as shown in FIG. 31, the plunger 115 a is attracted and moved in the direction of the arrow in the figure against the urging force of the spring 114, so that the connecting bar 113 is also When the link 110 is moved in the direction of the arrow in the drawing, and the link 110 is rotated in the direction of the arrow in the drawing (clockwise) around the rotation shaft 111, the pulley shaft 83d of the pulley 83 that has occupied the home position is shown by the arrow in the drawing. The pulley 83 is biased to the downstream side in the paper transport direction of the second transport means 7 via the transport belt 82 and occupies the bias position.

  The configuration related to the control around the sheet conveying device 5F of the present embodiment will be briefly described with reference to FIG. A sheet detection sensor 39 as a sheet detection unit that detects the leading edge of the sheet is disposed below the inner guide member 70 shown in FIG. 31 in a state that does not hinder the conveyance of the sheet. The paper detection sensor 39 is composed of a reflective photosensor. For example, the uppermost sheet S on the outer peripheral surface of the pickup roller 60 shown in FIG. 15 has a constant sheet conveyance distance from the position where the sheet detection sensor 39 is disposed, and the uppermost position of the pickup roller 60 starts to rotate. The linear velocity of the sheet is calculated by the CPU 44 using a timer provided in the control unit 43 from the time from the sheet S being fed to the sheet detection sensor 39 via the rotational drive of the first conveying unit 6. By calculating (linear velocity), it is possible to know the time immediately before the trailing edge of the sheet S passes through the nip portion of the second transport unit 7 and the like. Note that. A reflection type photo sensor or a transmission type photo sensor for detecting a state immediately before the trailing edge of the sheet S completely passes through the nip portion of the second conveying means 7 is provided in the vicinity of the nip portion without being calculated by the CPU 44. It doesn't matter. Further, the sheet linear velocity detecting means for detecting the linear velocity of the sheet is not limited to the sheet detecting sensor 39, and the sheet detecting sensor 39 and, for example, the sheet detecting means for detecting the leading edge and the trailing edge of the sheet S shown in FIG. The paper feed sensor 88 may be used in combination.

As shown in FIG. 31, a non-illustrated stationary member of the opening / closing guide is provided with a home position sensor 40 including a limit switch for detecting the home position of the pulley shaft 83d as the shaft of the first belt holding and rotating member. It is installed. The home position sensor 40 is not limited to a limit switch, and may be, for example, a light shielding plate protruding from a link member, a transmission type photo sensor that is selectively engaged with the light shielding plate at the home position of the belt conveying means 8F, or the like.
The CPU 44, via the input port and sensor input circuit, and the like, a feed sensor 88, a vertical conveyance sensor 89, a thickness detection sensor 41, the start switch and various keys (not shown) of the operation panel 95 as an operation unit. Electrically connected.

The sheet feeding sensor 88 and the vertical conveyance sensor 89 detect the arrival time by using the arrival time from when the sheet from the sheet feeding tray 51 serving as the sheet storage unit is fed until it reaches the second conveyance unit 7. It has a function as a means. This arrival time is the time from when the leading edge of the paper is detected to be ON by the paper feed sensor 88 to when it is detected to be ON by the vertical conveyance sensor 89, by a timer 48 as a time measuring means that is also an internal timer of the control device 43. This is what the CPU 44 recognizes.
The thickness detection sensor 41 has a function as a sheet type detection unit that detects a paper type (sheet type) that is a paper type including the thickness of the paper. In this embodiment, the thickness of the sheet (sheet) is detected. It functions as a detection means. As a specific example of the thickness detection sensor 41, for example, a known sensor that detects the thickness of a sheet by detecting the amount of light that passes through the sheet when laser light is projected onto the sheet is used. The thickness detection sensor 41 is appropriately disposed in a sheet conveyance path or the like between the pickup roller 60 and the first conveyance unit 6 in the sheet feeding device 3. Note that the sheet thickness detection means is not limited to the thickness detection sensor 41, and a sensor that detects the weight of a predetermined number of sheets of a predetermined size on the paper feed tray 51 and indirectly detects the thickness of the sheet. All known sensors may be used.

  In FIG. 32, the control means 43 is for mainly performing on / off control of the solenoid 115 of the displacement means 109 of the paper transport device 5F, control of the number of driving pulses supplied to the paper feed motor, and the like. Hereinafter, for the sake of simplicity, main control means (main control device) (not shown) is assumed to control the overall operation of the copying machine 1 except for the control of the paper transport device 5F of the paper feed device 3 shown in FIG. The main control device and the control means (control device) 43 will be described as transmitting and receiving a command signal, an on / off signal, a data signal, and the like. The main control unit and the control unit 43 are provided, for example, on a control board (not shown) on the image forming apparatus main body 2 side shown in FIG. When the paper feeding device 3 is a unit of movement as a product form, the control unit 43 may be provided on the main body side of the paper feeding device 3.

The control means 43 includes a CPU (central processing unit) 44, an I / O (input / output) port (not shown), a ROM (read only storage device) 45, a RAM (read / write storage device) 46, a timer (not shown), and the like. And a microcomputer having a configuration in which they are connected by a signal bus.
The CPU 44 receives the start switch and various keys (not shown) of the operation panel 48 as an operation unit having the operation screen unit of the touch panel system, the sheet detection sensor 39, and the like via the input port and each sensor input circuit. The home position sensor 40 and the thickness detection sensor 41 are electrically connected.

  On the operation panel 48, as various keys, a numeric keypad (not shown) for setting and setting the number of sheets S to be fed and the like, and a paper feed stage (for storing relatively high rigidity paper such as cardboard) A high-rigidity paper (high-rigidity sheet) selection key or its paper feed stage selection key for generating a signal for selecting and setting the paper feed tray 51 and the paper conveyance device 5F) and feeding and conveying the paper S, and a thick paper A signal for selecting and setting a paper feed stage (paper feed tray 51 and paper transport device) in which paper with relatively low rigidity such as plain paper and thin paper other than the paper is stored and driving the paper S to be fed and transported A plain paper selection key, a thin paper selection key, or a paper feed stage selection key thereof are provided.

The CPU 44 has a calculation function for obtaining the sheet linear velocity by calculation based on an output signal (data signal) from the sheet detection sensor 39. Further, the CPU 44 sets the time immediately before the trailing edge of the sheet S passes through the nip portion of the second conveying unit 7 from the position where the leading edge of the sheet starts to rotate the pickup roller 60 (starts rotation of the sheet feeding motor 23). There is also an arithmetic function for calculating from a predetermined transport distance of the preset paper S that reaches the nip portion of the second transport means 7 at the rear end and the calculated linear speed of the paper.
The CPU 44 is electrically connected to the paper feed motor 23 via the output port and a stepping motor drive circuit (not shown), and to a solenoid 115 via a solenoid drive circuit (not shown). Are transmitted to the motor drive circuit and the solenoid drive circuit, respectively.
The RAM 46 inputs / outputs these signals by temporarily storing the calculation results of the CPU 44 or storing the output signals from the high-rigidity paper selection key of the operation panel 48 and the paper detection sensor 39 as needed. The ROM 45 stores in advance an “operation program”, “relationship data on the number of pulses supplied to the paper feed motor 23 via a motor drive circuit (not shown)” and the like for the CPU 44 to perform a control function described later. . The timer has a function as time measuring means for measuring time.

For example, when the sheet is conveyed from the second conveyance path B, the CPU 44 detects that the sheet has been conveyed from the sheet conveying apparatus 5 ′ instead of the lowermost sheet conveying apparatus 5 in FIG. Based on an output signal from a paper detection sensor (not shown) and an output signal from the home position sensor 40 disposed in the lower paper transport device 5 ′, displacement of the pulley 83 and the pulley shaft 83d is prohibited, and the pulley 83 And the first function of controlling the solenoid 115 of the displacement means 109 to be turned off so that the pulley shaft 83d occupies the home position.
The CPU 44 is transported from the first transport means 6 via the first transport path A based on output signals from the timer (not shown), the paper detection sensor 39, the home position sensor 40, the thickness detection sensor 41, and the operation panel 48. When the received sheet is a relatively rigid sheet such as a thick sheet, and the leading end of the sheet enters the nip portion of the second conveying means 7 (grip roller 81 and conveying belt 82), the pulley 83 and the pulley It has a second function of controlling the solenoid 115 of the displacement means 109 to be turned off so that the shaft 83d occupies the home position.
The CPU 44 is transported from the first transport means 6 via the first transport path A based on output signals from the timer (not shown), the paper detection sensor 39, the home position sensor 40, the thickness detection sensor 41, and the operation panel 48. The received paper is relatively stiff paper such as thick paper, and the pulley shaft 83d is moved immediately before the rear end of the paper passes through the nip portion of the second transport means 7 (grip roller 81 and transport belt 82). It has a third function of controlling the on / off driving of the solenoid 115 of the displacement means 109 so as to occupy the biased position by being displaced.
The CPU 44 also passes the first transport path A through the first transport path A based on output signals from the timer, paper detection sensor 39, home position sensor 40, thickness detection sensor 41 and operation panel 48 (not shown). When it is determined that the conveyed sheet is a sheet having relatively low rigidity such as plain paper or thin paper, the solenoid 115 of the displacement unit 109 is controlled to be turned off so that the pulley 83 and the pulley shaft 83d occupy the home position. It has a fourth function.

Based on the above configuration, the operation of the main part will be described.
First, for example, the sheet feeding device 3 shown in FIG. 9 is borrowed, and the sheet feeding device 5F in place of the upper sheet feeding tray 51 and the sheet conveying device 5 is selected as a predetermined sheet feeding stage in the sheet feeding device 3. The conveyance operation in this case will be described. Starts after the upper paper feed tray 51 and the paper transport device 5F are selected by the operation of the paper feed stage selection key (not shown) or the high rigidity paper selection key (not shown) on the operation panel 48 and the copy conditions are selected and set by various key operations. When the switch is turned on, the paper feeding operation is started. The second transport means 7 (grip roller 81) is fed while the leading edge of the paper transported from the first transport means 6 via the first transport path A at the start of the paper feeding operation is in contact with the belt transport surface 82a. The solenoid 115 of the displacement means 109 remains off so that the pulley 83 and the pulley shaft 83d occupy the home position until they enter the nip portion of the conveyor belt 82).
As described above, when the leading edge of the paper enters the nip formed by the grip roller 81 and the conveyance belt 82, the solenoid 115 is in an off state, so that a plurality (in this embodiment, in the paper width direction). 3) Since the positions where the nip portion of the conveying belt 82 is formed in the belt conveying means 8F that is arranged are all the same position with respect to the grip roller 81, the entry of the leading edge of the sheet into the nip can be stabilized.

  Next, the sheet S is nipped and conveyed at the nip portion between the grip roller 81 and the conveyance belt 82 and further conveyed downstream, but the rear end of the sheet S passes through the nip portion between the grip roller 81 and the conveyance belt 82. Immediately before, when the solenoid 115 is turned on against the biasing force of the spring 114, the plunger 115a and the connecting bar 113 are pulled down in the direction of the arrow in FIG. 31, and the link 110 moves the pulley shaft 83d in FIG. By swinging so as to push up in the middle arrow (clockwise) direction, the pulley shaft 83d is shifted with respect to the rotation drive shaft 81a of the grip roller 81, and the pulley 81 and the pulley shaft 83d occupy a biased position and stop. .

In the same way as described in the fourth embodiment, in the case of stiff paper such as thick paper, the guide surface 71a of the transport guide member 71 is separated and the rear end of the paper S is the belt transport surface 82a and the transport. The trailing edge noise when contacting a portion that is a guide means other than the conveyance belt 82 such as the guide surface 72a of the guide member 72 becomes a problem, but the rear end of the sheet S is the guide surface of the conveyance guide member 72. Since the timing of contact with 72a can be shifted in the paper width direction (soft landing), it is possible to reduce the trailing edge splash sound. In the present embodiment, since the solenoid 115 is used as the drive means / drive source, there are advantages that the software control configuration is simple and the cost is very low.
When the trailing edge of the sheet S completely passes through the nip portion between the grip roller 81 and the conveying belt 82, and at the same time as the next sheet feeding operation is started by the rotation of the sheet feeding motor 23 by a predetermined number of steps. The solenoid 115 is driven off. As a result, the reverse operation described above is performed by the urging force of the spring 114, and the pulley shaft 83d is arranged substantially horizontally with respect to the rotation drive shaft 81a of the grip roller 81, and the pulley 81 and the pulley shaft 83d are It will be returned to the home position.

(Modification 2 of the fifth embodiment)
With reference to FIG. 33 and FIG. 34, the modification 2 of 5th Embodiment is demonstrated.
In the second modification shown in FIGS. 33 and 34, only the paper transport device 5G instead of the paper transport device 5F is used as compared with the paper transport device 5F of the fifth embodiment shown in FIGS. 31 and 32. Is different. The configuration of the second modification other than the differences is the same as that of the copier 1 shown in FIG. 9 of the first embodiment.
As compared with the paper transport device 5F of the fifth embodiment shown in FIGS. 31 and 32, the paper transport device 5G of Modification 2 is replaced with a displacement means 109 as shown in FIGS. 33 and 34. If necessary, specifically, the displacement means 120 for displacing the pulley shaft 83d of the pulley 83 to the downstream side in the paper conveyance direction of the second conveyance means 7 according to the paper type (sheet type), and The main difference is that instead of the control means 43, a control means 43A for controlling the displacement means 120 is used.

The displacing means 120 has a link 121 whose one end abuts and is connected to the pulley shaft 83d of the belt conveying means 8F, a link-equipped gear 122 to which the other end of the link 121 is fixed via a gear shaft 122a, An idler gear 123 that meshes with the gear 122 and a stepping motor 124 as a driving means having a motor gear 124a that meshes with the idler gear 123 fixed to its output shaft are mainly constituted.
The link-equipped gear 122 and the idler gear 123 are rotatably supported by immovable members of an open / close guide (not shown) via respective gear shafts. The stepping motor 124 is fixed to an immovable member of an opening / closing guide (not shown).

  The stepping motor 124 has the simplest configuration among drive motors that are driven to rotate by pulse input. When a predetermined number of pulses are supplied to the stepping motor 124 and the stepping motor 124 is turned on, as shown in FIG. 33, the motor gear 124a is moved in the direction of the arrow (clockwise) in FIG. 33 by a predetermined number of steps corresponding to the predetermined number of pulses. Then, the idler gear 123 and the link-equipped gear 122 are respectively rotated in the directions of the arrows (counterclockwise and clockwise) in the figure, and the rotational driving force is transmitted to the link 121 integrated with the link-equipped gear 122. The pulley shaft 83d of the pulley 83 occupying the home position is lifted / displaced in the direction of the arrow in the figure, and the pulley 83 is biased to the downstream side in the paper transport direction of the second transport means 7 via the transport belt 82. Occupy position.

With reference to FIG. 34, the configuration related to the control around the sheet conveying device 5G of the present modification will be described focusing on the differences from the fifth embodiment. In FIG. 34, the control means 43A mainly controls the number of driving pulses supplied to the stepping motor 124 of the displacing means 120 of the paper transport device 5G, and controls the number of driving pulses supplied to the paper feed motor. It is. The configuration and control means 43A related to the control around the sheet conveying device 5G are the same as those in the fifth embodiment except for the following.
The CPU 44A of the control means 43A is electrically connected to the paper feed motor 23 via the output port and a stepping motor drive circuit (not shown), and is driven to drive the stepping motor 124 via a stepping motor drive circuit (not shown). A command signal to be controlled is transmitted to each motor drive circuit.
The ROM 45A contains an “operation program”, “relationship data on the number of pulses supplied to the paper feeding motor 23 and the stepping motor 110 via a stepping motor drive circuit (not shown)” for the CPU 44A to perform a control function described later, and the like. Stored in advance.

When the sheet is conveyed from the second conveying path B, the CPU 44A detects, for example, that the sheet has been conveyed from the lowermost sheet conveying apparatus 5 ′ (not shown in FIG. 9). Based on an output signal from a sheet detection sensor (not shown) disposed at 5 ′ and an output signal from the home position sensor 40, displacement of the pulley 83 and the pulley shaft 83d is prohibited, and the pulley 83 and the pulley shaft 83d are The stepping motor 124 of the displacing means 120 has a first function of performing off-drive control (control not to perform pulse supply, the same applies hereinafter) so as to occupy the home position.
The CPU 44A is transported from the first transport means 6 via the first transport path A based on output signals from the timer (not shown), the paper detection sensor 39, the home position sensor 40, the thickness detection sensor 41, and the operation panel 48. The received sheet is a sheet having a relatively high rigidity such as a thick sheet, and the leading end portion of the sheet comes into contact with the belt conveying surface 82a and is conveyed while the second conveying means 7 (the grip roller 81 and the conveying belt 82). When entering the nip portion, the stepping motor 124 of the displacing means 120 is controlled to be turned off so that the pulley 83 and the pulley shaft 83d occupy the home position.

The CPU 44A is transported from the first transport means 6 via the first transport path A based on output signals from the timer (not shown), the paper detection sensor 39, the home position sensor 40, the thickness detection sensor 41, and the operation panel 48. And the pulley 83 and the pulley immediately before the trailing edge of the paper passes through the nip portion of the second conveying means 7 (the grip roller 81 and the conveying belt 82). The shaft 83d is displaced to have a third function of performing on-drive control (supplying a predetermined number of pulses for normal rotation) of the stepping motor 124 of the displacement means 120 so as to occupy the bias position.
The CPU 44A is transported from the first transport means 6 via the first transport path A based on output signals from the timer (not shown), the paper detection sensor 39, the home position sensor 40, the thickness detection sensor 41, and the operation panel 48. The received sheet is a sheet having relatively high rigidity such as a thick sheet, and after the trailing end of the sheet has completely passed through the nip portion of the second conveying means 7, the pulley 83 and the pulley shaft 83d return to the home position. As described above, the stepping motor 124 of the displacing means 120 has a fourth function of performing on-drive control (supplying a predetermined number of pulses for reverse rotation).
Further, the CPU 44A, based on output signals from the timer (not shown), the paper detection sensor 39, the home position sensor 40, the thickness detection sensor 41, and the operation panel 48, passes the first conveyance path A from the first conveyance means 6. When it is determined that the conveyed paper is a relatively low rigidity paper such as plain paper or thin paper, the stepping motor 124 of the displacing means 120 is controlled to be off so that the pulley 83 and the pulley shaft 83d occupy the home position. Has a fifth function.

Based on the above configuration, the operation of the main part will be described.
First, a high-stiffness paper feeding operation similar to the operation of the fifth embodiment is started, and the paper transported from the first transporting unit 6 via the first transport path A at the start of the paper feeding operation. The pulley 83 and the pulley shaft 83d occupy the home position until they enter the nip portion of the second conveying means 7 (the grip roller 81 and the conveying belt 82) while being conveyed while abutting on the belt conveying surface 82a. As described above, the stepping motor 124 of the displacing means 120 remains off (pulse supply is not performed).
As described above, when the leading edge of the paper enters the nip formed by the grip roller 81 and the conveyor belt 82, the stepping motor 124 is in an off state, so that a plurality (in this modification example, in the paper width direction). 3) Since the positions where the nip portion of the conveying belt 82 is formed in the belt conveying means 8F that is arranged are all the same position with respect to the grip roller 81, the entry of the leading edge of the sheet into the nip can be stabilized.

Next, the sheet S is nipped and conveyed at the nip portion between the grip roller 81 and the conveyance belt 82 and further conveyed downstream, but the rear end of the sheet S passes through the nip portion between the grip roller 81 and the conveyance belt 82. Immediately before, the stepping motor 124 is supplied with a predetermined number of normal rotation pulses and is turned on, so that the link 121 pushes up the pulley shaft 83d via the gear train in the direction of the arrow (clockwise) in FIG. The pulley shaft 83d is shifted with respect to the rotational drive shaft 81a of the grip roller 81, and the pulley 81 and the pulley shaft 83d occupy the biased position and stop.
Thus, as described in the fifth embodiment, the timing at which the trailing edge of the sheet S contacts the guide surface 72a of the conveyance guide member 72 can be shifted in the sheet width direction (soft landing). It is possible to reduce the edge noise.
In this modification, since the stepping motor 124 is used as the driving means and driving source, compared with the solenoid 115 used in the fifth embodiment, the control is complicated and the cost is high. Since the motor drive amount can be easily varied according to the thickness of the sheet, the shift amount between the rotation drive shaft 81a of the grip roller 81 and the pulley shaft 83d can be increased as the sheet thickness increases. As a result, the effect of reducing the splash sound at the rear end of the paper is also increased.
When the trailing edge of the sheet S completely passes through the nip portion between the grip roller 81 and the conveying belt 82, and at the same time as the next sheet feeding operation is started by the rotation of the sheet feeding motor 23 by a predetermined number of steps. When the predetermined number of reverse pulses is supplied to the stepping motor 124 and is turned on again, the operation reverse to that described above is performed, and the pulley shaft 83d is moved relative to the rotational drive shaft 81a of the grip roller 81. As a result, the pulley 81 and the pulley shaft 83d are returned to the home position.

  As described above, the respective sheet conveying devices 5, 5A, 5B, 5C, 5D, 5E, 5F, and 5G shown in FIGS. 1 to 4, 6 to 8, 9 to 12, and 15 to 28 are used. In the belt conveying means 8, 8A, 8B, 8D, 8E, 8F, one of the opposed pairs of the second conveying means 7 (nipping and conveying means) is the leading edge or the leading edge (tip, leading edge surface, leading edge) of the sheet (sheet). Nip part (grip part) with the grip roller 81 while maintaining the contact / abutting state and gradually increasing the contact area depending on the degree of rigidity of the paper. It can be said that this is an example of movement guide means for moving and guiding the sheet S toward the head. Therefore, the movement guide means is not limited to the belt conveyance means 8 and 8A to 8F, and may be anything as long as it has the above-described configuration and function and exhibits the above-described effects.

In the above embodiments, examples, and modifications, as shown in FIG. 1, the present invention is conveyed from the sheet storage means (paper feed tray 51) in the image forming apparatus that is a copying machine to the image forming means main body. However, the present invention is not limited to this, and the image forming apparatus is not limited to this example, and the front end of the image forming apparatus is directed upward from the upper part of the fixing device 11 in the apparatus main body. A paper transport device (for example, see FIG. 29B) configured to discharge the paper S to be discharged from the apparatus main body toward the paper discharge tray 9 in a substantially horizontal direction, or provided outside the apparatus main body. The sheet placed by the user on the substantially horizontal manual feed tray 67 is pulled into the apparatus main body while maintaining the horizontal posture, and the posture is changed upward to reach the image forming unit in the apparatus main body in the vertical direction. Transporting paper that is transported to the transport path It may be applied to a device.
That is, in the above-described embodiment and modification, the example in which the different paper (sheet) conveyance direction is changed from the substantially horizontal direction to the upward direction in the vertical direction (substantially vertical upward direction) has been described. Without being limited, it is changed from substantially horizontal to downward in the vertical direction (substantially vertically downward), or from vertically downward or upward to substantially horizontal (for example, FIG. 29A). Or both may be in an oblique direction or the like.

  In each of the above-described embodiments, examples, and modifications, the first transport unit and the second transport unit are both nipping and transporting units. However, depending on the transport direction of each transport unit alone, the lower surface of the transport target is set. If it is only necessary to support and convey, it is not necessary to use a nipping / conveying means in which a nipping portion by an opposing member is formed.

The members constituting the first conveying unit, the second conveying unit, and the pickup roller are not limited to those described above, and are substantially long cylindrical roller members that have a predetermined length in the axial direction of each rotating shaft. The roller member may be a short cylindrical roller member as appropriate, or a plurality of roller members or roller members may be intermittently disposed at a predetermined interval on one rotating shaft. May be.
In addition, a guide surface formed by several guide members in the outer and inner contour directions in each of the above-described embodiments is positioned at the above-described several intervals where no roller member or roller member is disposed. Good. If these guide surfaces are arranged in an appropriate regular symmetry with respect to the conveyance center line in the conveyance direction, a belt-shaped guide surface may be formed in the sheet (sheet) conveyance direction, or a substantially linear guide A surface may be formed, or these may be mixed as appropriate.

  In each of the above-described embodiments, examples, and modifications, the FRR paper feed method is adopted as the paper feed separation mechanism. However, the present invention is not limited to this, and the paper that has been fed in a predetermined multi-feed due to friction is separated. For example, an appropriate frictional separation method may be employed as long as the separation mechanism allows only one sheet to continue to advance in the conveyance direction. For example, instead of the reverse roller, a separation claw may be used instead of the above-described feed roller. Alternatively, a friction pad system having a configuration in which a friction pad that is a fixing member is in pressure contact may be employed. That is, in this friction pad system, the friction pad as a friction member is pressed against the feed roller with an appropriate separation angle and separation pressure, and the paper is placed in the nip between the feed roller and the friction pad formed thereby. I try to let it pass. Therefore, according to the paper feed separation mechanism employing the friction pad method, even if two sheets are pulled out in the overlapping state, the lower sheet receives the resistance from the friction pad between the overlapping sheets. Since it is greater than the resistance due to friction, further movement in the paper transport direction is prevented. On the other hand, the upper sheet is set so that the conveyance force received from the feed roller is larger than the resistance caused by the friction between the overlapping sheets and larger than the resistance received from the friction pad. Only continues in the transport direction.

The present invention relates to an image forming apparatus relating to a printer including not only the monochrome copying machine 1 but also a color copying machine, a monochrome laser printer, an inkjet printer, a printer using an ink transfer ribbon, and the like. The transfer device can be applied and applied.
In a color copying machine, after transferring to a tandem color image forming apparatus of a direct transfer system that sequentially transfers and superimposes a sheet (sheet) while being transferred by a transfer body, or after being transferred to an endless intermediate transfer belt as an intermediate transfer body, The present invention can be similarly applied to a tandem type image forming apparatus that batch-transfers to a sheet. Needless to say, the endless belt-like photoconductor can be similarly applied to a single image forming apparatus.

The present invention is not limited to an in-body discharge type image forming apparatus that discharges paper between an image forming unit and a scanner, for example, and an image in which paper is discharged to a paper discharge tray provided on a side portion of the image forming apparatus main body. You may apply also to a formation apparatus. In addition, a substantially vertical conveying path is formed for the paper fed from the paper feeding device 3 toward the upper portion of the image forming apparatus main body 2. However, the present invention is not limited to this, and the paper is discharged from the paper feeding device to the paper discharge tray. The present invention can also be applied to an image forming apparatus in which the conveyance path up to is not substantially vertical.
The present invention relates to a sheet conveying apparatus for conveying a sheet (paper) from a sheet storage means (paper feed tray) or a sheet stacking means (paper feed table) to a printing unit main body in a printing apparatus including a stencil printing machine. May also be applied.

In the copying machine 1 as the image forming apparatus described above, a document to be read is set manually, but an ADF (automatic document feeder) for automatically reading a plurality of documents (sheets) is provided. The sheet conveying apparatus of the present invention may be applied to the ADF in an equipped copying machine or printing apparatus.
Further, the image forming apparatus is not limited to a copying machine, but is a facsimile, a printer, an ink jet recording apparatus, a printing apparatus, an image reading apparatus mainly having an image reading function having a scanner for reading an image from a document, or the like. You may apply to the compound machine etc. which combined at least two of them. In any case, it is most suitable for equipment and devices that need to change the sheet conveyance direction while saving space on the sheet conveyance path, targeting a variety of sheet types as paper types. It can be set as a simple sheet conveying apparatus.

  The present invention is not limited to a sheet conveying device arranged in a plurality of paper feeding stages. For example, in the paper feeding device 3 shown in FIG. 1, the upper paper feeding tray 51 and the paper conveying device 5 ′ are removed, The present invention can also be applied to a sheet conveying apparatus constituted by only a single sheet feeding tray 51 and a sheet conveying apparatus 5 (see claim 1).

  As described above, the present invention has been described with respect to specific embodiments and modifications. However, the technical scope disclosed by the present invention is limited to those exemplified in the above-described embodiments and modifications. It may be configured by appropriately combining them. (For example, the above-described embodiments and modifications of the present invention can be applied to the first to third examples of the invention of the prior application. It will be apparent to those skilled in the art that various embodiments, modifications, and examples can be made within the scope of the present invention in accordance with the necessity and application.

1 is a schematic front view showing an overall configuration of an image forming apparatus having a paper transport device to which the present invention is applied. FIG. 2 is an enlarged cross-sectional view of a main part showing an operation state in which the leading edge of the paper reaches a belt conveying unit, showing the paper conveying device of FIG. FIG. 4 is an enlarged cross-sectional view of a main part showing an operation state immediately before the leading edge of the paper reaches the nip portion of the second transport means in the paper transport device of FIG. 2. FIG. 3 is an enlarged cross-sectional view of a main part of the paper transport device for explaining the first embodiment. 6 is a graph for explaining a test result related to variation in paper-type transport time in Example 1. FIG. 3 is a cross-sectional view of a main part showing a paper transport device different from FIG. 2 to which the present invention is applied and a paper feed tray stage around the paper transport device. FIG. 8 is an enlarged cross-sectional view of a main part showing an operation state in which the leading edge of the paper reaches the belt conveying means in the paper conveying apparatus of FIG. 7. FIG. 8 is an enlarged cross-sectional view of a main part showing an operation state immediately before the leading edge of the paper reaches the nip portion of the second transport means in the paper transport device of FIG. 7. It is a schematic front view which shows the whole structure of the image forming apparatus which has another paper conveyance apparatus to which this invention is applied. FIG. 10 is an enlarged cross-sectional view of a main part illustrating an operation state when the leading end of the sheet is sent out from the first conveying unit in the sheet conveying apparatus of FIG. 9. It is an expanded sectional view of the principal part of FIG. FIG. 10 is an enlarged cross-sectional view of a main part showing an operation state after the leading edge of the paper reaches the belt conveying means in the paper conveying device of FIG. 9. FIG. 10 is an enlarged cross-sectional view of a main part showing a defective state when the leading edge of the paper is sent out from the second transport means and contacts the guide member in the paper transport device of FIG. 9. FIG. 10 is an enlarged cross-sectional view of a main part illustrating a malfunction state when the leading end of the sheet is sent out from the second transport unit and comes into contact with the guide member in the case where the elastic mylar is disposed in the sheet transport apparatus of FIG. 9. FIG. 4 is a cross-sectional view of the main parts around a first and second transport means, an outer guide member on the image forming apparatus main body side, and a third transport path in the paper transport apparatus of the first embodiment. FIG. 6 is a cross-sectional view of the main parts around a first and second transport means, an outer guide member on the image forming apparatus main body side, and a third transport path in a paper transport apparatus of a second embodiment. FIG. 10 is a simplified perspective view showing a drive mechanism in a sheet conveying device according to second and third embodiments. It is a schematic front view of the principal part of FIG. FIG. 10 is a cross-sectional view of a main part around a first and second transport means, an outer guide member on the image forming apparatus main body side, and a third transport path in a paper transport apparatus according to a third embodiment. FIG. 9 is a perspective view of a main part when a belt conveyance unit and a conveyance guide member are viewed from a grip roller side in a paper conveyance device according to Modification 1; FIG. 10 is a cross-sectional view of a main part around first and second transport means in a paper transport apparatus according to Modification 1; FIG. 10 is a perspective view of a belt conveying unit and its surroundings in a sheet conveying apparatus according to a first modification viewed from the grip roller side. FIG. 9 is a perspective view of a belt conveyance unit and its surroundings in a sheet conveyance apparatus according to a first modification when viewed from the back side of a conveyance guide member. FIG. 10 is a cross-sectional view of a main part around a second transport unit in a paper transport apparatus according to a first modification. FIG. 10 is a cross-sectional view of the main parts around the first and second transport means, the outer guide member on the image forming apparatus main body side, and the third transport path in the paper transport apparatus of the fourth embodiment, where the leading edge of the paper is the second transport It is sectional drawing which shows the conveyance operation immediately after exiting the nip part of a means. In FIG. 25, it is sectional drawing which shows the conveyance operation immediately after the rear end of a sheet | seat slipped out of the nip part of the 2nd conveyance means. FIG. 10 is a perspective view of a main part of a periphery of a belt conveying unit in a paper conveying apparatus according to a fourth embodiment viewed from the grip roller side. FIG. 28 is a perspective view of a main part of the periphery of the belt conveyance unit of the paper conveyance device of FIG. 27 as viewed from the back side of the conveyance guide member. (A), (b) is a simplified front view for explaining an arrangement example of the first and second conveying means of the sheet conveying apparatus according to the difference in the sheet conveying path. (A) is a schematic perspective view showing a specific opening / closing configuration on the sheet feeding apparatus main body side in the second embodiment and the like, and (b) is an opening / closing guide for removing jammed paper (jam paper). It is a simplified sectional view of the important section showing the state where it opened. FIG. 10 is a cross-sectional view of a main part around a displacement unit disposed in a belt conveyance unit of a second conveyance unit in a paper conveyance device according to a fifth embodiment. It is a block diagram which shows the control structure of the principal part in the paper conveying apparatus of 5th Embodiment. FIG. 10 is a cross-sectional view of a main part around a displacement unit disposed in a belt conveyance unit of a second conveyance unit in a paper conveyance device according to Modification 2; FIG. 10 is a block diagram illustrating a control configuration of a main part in a sheet transport device according to a second modification.

Explanation of symbols

1 Copying machine (image forming device)
2 Image forming apparatus body 3 Paper feeding device 4 Document reading devices 5A, 5B, 5C, 5D, 5E, 5F, 5G Paper conveying device (sheet conveying device)
6 First conveying means (first conveying means)
7 Second transport means (second transport means)
8, 8A-8F Belt conveying means (movement guide means)
9 Discharge tray 10 Photoreceptor unit 10A Photoreceptor 11 Fixing device 12 Developing device 13 Transfer device 21 Registration roller pair 22 Drive mechanism 23 Paper feed motors 43 and 43A Control means 50 Bottom plate (sheet stacking means)
51 Paper feed tray (sheet storage means)
60 Pickup roller 61 Feed roller (one of the opposing pair of first conveying means)
62 Reverse roller (the other of the opposing pair of the first conveying means)
67 Manual feed tray 70 Conveyance guide member (inner side, guide member)
71 Conveying guide member (outer side, guide member)
72 Transport guide member (outer side of longitudinal transport path, guide member)
72a Guide surface 72b Conveyance guide rib 73 Conveyance guide member (for forming an inlet from the paper feed tray to the conveyance path)
79 Opening / Closing Guide (Sheet Conveyor Body)
80 Housing (sheet transport device main unit)
81 Grip roller (one of the opposite pair of the second conveying means, the rotation conveying driving means, the rotation conveying driving member)
81a Grip roller rotational drive shafts 82, 82A, 82B, 83C, 82D, 82E Conveying belt (belt as the other of the opposed pair of the second conveying means)
82a Conveying surface 83 of conveying belt Pulley (constituent member of belt conveying means as one of opposed pair of first conveying means, first belt holding rotating member)
83a, 83b, 83c Pulley shaft (downstream shaft of the belt holding and rotating member)
84 Pulley (constituent member of belt conveying means as one of the opposed pair of first conveying means, second belt holding and rotating member)
84a, 84b Pulley shaft 86, 96 Belt support member (support member)
91, 92, 97 Spring (biasing means)
99,99 'Nip (nip)
100 Outer guide members 109 and 120 Displacement means A First transport path (sheet transport path)
B Second transport path (sheet transport path)
C Third transport path (sheet transport path)
D Fourth transport path (sheet transport path)
R1 transport path R2 manual feed path R3 reverse transport path S paper (sheet / sheet-like recording medium, image forming medium)
Y Paper width direction (sheet width direction)
θ Entry angle δ Shift amount

Claims (14)

First conveying means for conveying a sheet;
A second transport disposed downstream of the first transport means in the sheet transport direction and transports the sheet transported by the first transport means in a sheet transport direction different from the sheet transport direction of the first transport means. Means,
At least the second transport unit of the first transport unit and the second transport unit is a sandwich transport unit that forms a sandwiching unit that sandwiches and transports the sheet,
A movement guide unit disposed in an outer direction of a sheet conveyance path formed between the first conveyance unit and the second conveyance unit, and configured to move and guide the sheet toward the sandwiching portion of the second conveyance unit; A sheet conveying apparatus comprising:
A sheet conveying apparatus configured to be able to change a sheet conveying direction of a sheet conveyed by a second conveying unit to a direction facing the movement guide unit. First conveying means for conveying a sheet;
A second transport disposed downstream of the first transport means in the sheet transport direction and transports the sheet transported by the first transport means in a sheet transport direction different from the sheet transport direction of the first transport means. Means,
A first sheet conveying path formed between the first conveying means and the second conveying means;
A second sheet conveying path that is formed from upstream of the second conveying means to the second conveying means, and is different from the first sheet conveying path;
A merged conveyance path where the first sheet conveyance path and the second sheet conveyance path merge on the upstream side of the second conveyance means;
A movement guide means arranged in the outer direction of the merging conveyance path and moving and guiding the sheet toward the second conveyance means;
At least the second conveying means of the first conveying means and the second conveying means is a sheet conveying apparatus which is a nipping and conveying means for forming a nipping portion for nipping and conveying the sheet,
A sheet conveying apparatus configured to be able to change a sheet conveying direction of a sheet conveyed by a second conveying unit to a direction facing the movement guide unit. The movement guide means is a belt conveyance means including a belt that conveys a sheet toward the clamping unit,
3. A sheet conveying apparatus according to claim 1, wherein the sheet conveying direction of the sheet conveyed by the second conveying means is changeable to a direction facing a conveying surface in contact with the sheet of the belt. . The belt conveying means has at least a pair of belt holding and rotating members, in which one of the opposed pairs of the holding conveying means in the second conveying means holds the belt movably and is pivotally supported.
The other of the opposing pair is a rotationally supported rotation member that is pivotally supported,
The shaft of the belt holding and rotating member on the side forming the clamping portion is arranged to be deviated toward the downstream side in the sheet conveying direction of the second conveying means with respect to the axis of the rotating and conveying member. The sheet conveying apparatus according to claim 3. The belt conveying means has at least a pair of belt holding and rotating members, in which one of the opposed pairs of the holding conveying means in the second conveying means holds the belt movably and is pivotally supported.
The sheet conveying apparatus according to claim 3 or 4, wherein the belt holding and rotating member on the side forming the clamping portion is formed of an elastic member.   6. The sheet conveying apparatus according to claim 3, wherein the belt is formed of a rubber having a relatively low hardness. The belt conveying means has at least a pair of belt holding and rotating members, in which one of the opposed pairs of the holding conveying means in the second conveying means holds the belt movably and is pivotally supported.
The belt conveying means is divided into a plurality of sheets in the sheet width direction orthogonal to the sheet conveying direction,
In the belt conveying means disposed on the center side in the sheet width direction, the shaft of the belt holding and rotating member on the side forming the clamping portion is clamped in the belt conveying means disposed on both sides in the sheet width direction. 7. The apparatus according to claim 3, wherein the second holding unit is arranged so as to be deviated toward a downstream side in a sheet conveying direction of the belt holding rotating member on a side where the portion is formed. The sheet conveying apparatus according to the description. The belt conveying means has at least a pair of belt holding and rotating members, in which one of the opposed pairs of the holding conveying means in the second conveying means holds the belt movably and is pivotally supported.
In accordance with the type of sheet, there is provided a displacing means including a driving means for displacing the shaft of the belt holding and rotating member on the side forming the clamping portion to the downstream side in the sheet conveying direction of the second conveying means. The sheet conveying apparatus according to claim 3.   9. The sheet conveying apparatus according to claim 8, wherein the driving unit is a solenoid.   The sheet conveying apparatus according to claim 8, wherein the driving unit is a driving motor that is rotationally driven by a pulse input.   The sheet conveying apparatus according to claim 1, wherein the sheet is a sheet having relatively high rigidity.   An image reading apparatus comprising the sheet conveying apparatus according to claim 1.   An image forming apparatus comprising the sheet conveying device according to claim 1 and / or the image reading device according to claim 12.   14. The image forming apparatus according to claim 13, wherein the image forming apparatus is any one of a copying machine, a facsimile machine, a printer, a printing machine, and an ink jet recording apparatus, or a complex machine combining at least two of them. apparatus.

Images