JP4861932B2 - Paper feeding device, image forming device - Google Patents

Description

  The present invention relates to a paper feeding device provided in an image forming apparatus such as a copying machine or a printing device, and in particular, the height of the uppermost surface of the stacked paper is increased by displacing a paper stacking unit in accordance with the paper stacking amount. The present invention relates to a paper feeding device which is set at a substantially constant position and sequentially feeds paper from the uppermost sheet, and an image forming apparatus using the same.

  For this type of paper feeding device, it is necessary to carry the paper well, and various techniques have been proposed. For example, in Patent Document 1, as a means for cleaning a roller, specifically, a conveyance roller, a mounting plate elastically deformed is provided inside a holding plate supported at both ends, and a cleaning member is attached to the mounting plate. Are disclosed. Further, Patent Document 2 includes a cleaning unit that cleans the surface of the paper feed roller, and further includes a secondary cleaning unit that cleans the cleaning unit. Are disclosed. Further, Patent Document 3 discloses a technique in which a sheet is stopped during sheet feeding and a roller to be cleaned is idled.

  Further, in Patent Document 4, for cleaning the guide plate, a guide unit that is in contact with the sheet on the side opposite to the sheet image surface on the downstream side of the transfer material conveyance belt is configured by a belt member, and the belt surface is cleaned. Are disclosed.

  Further, in Patent Document 5, in order to remove the adhesive substance on the end face of the sheet-like member, a cleaning roll rotating from four directions is brought into contact so as to surround the sheet-like member, and the adhesive substance on the side surface of the sheet-like member is removed. Are disclosed.

  Also, when sending paper with adhesive on the paper edge, such as label paper, it has been known that a PTFE (tetrafluoroethylene resin) film is attached to the inner wall of the side fence. .

Japanese Patent No. 2668612 Japanese Patent No. 3323802 JP 2000-128376 A JP 2001-255712 A JP-A-9-54295

  However, the technique disclosed in Patent Document 1 is a means for cleaning the transport roller, and is not a means for cleaning the side fence that regulates the paper position during paper feeding. Therefore, it is not easy to develop technology for cleaning the side fence. Further, the technique of Patent Document 2 is a means for cleaning the paper feed roller, and is not a side fence cleaning means for regulating the paper position at the time of paper feed. Furthermore, the technique of Patent Document 3 is a means for cleaning the conveyance roller, and is not a means for cleaning the side fence that regulates the paper position at the time of paper feeding, so that it is not easy to develop the technique for cleaning the side fence.

  Further, the technique of Patent Document 4 is a means for cleaning the paper transport guide plate, and is not a means for cleaning the side fence that regulates the paper position at the time of paper supply.

  The technique of Patent Document 5 is a means for removing the adhesive material on the end face of the stacked sheet-like member, and is not a means for cleaning the side fence that regulates the paper position during paper feeding. Is not easy.

  In addition, when a PTFE (polytetrafluoroethylene) film is affixed to the inner wall surface of the side fence, the adhesive (adhesive substance) hardly adheres to the inner wall surface of the side fence because PTFE is highly non-adhesive. If the adhesive (adhesive substance) adheres to the inner wall surface of the side fence over time, it becomes a resistance when the next sheet is fed, paper conveyance is delayed, and a non-feed jam occurs.

  The present invention has been made in view of such conventional problems, and a paper feeding device capable of improving the transportability of paper by improving the configuration of the inner wall surface of the side fence and removing adhered dirt, and the paper feeding device. An object of the present invention is to provide an image forming apparatus using the above.

  According to the first aspect of the present invention, in order to achieve the above object, the height of the uppermost surface of the stacked sheets can be increased by displacing the sheet stacking unit in accordance with the stacking amount of sheets. In a paper feeding device that is placed at a substantially constant position and sequentially feeds from the topmost paper, a cleaning member is provided in the paper stacking portion, and the cleaning member is positioned so as to sandwich the paper stacking portion. It is made to contact | abut with the inner wall surface of this.

  According to a second aspect of the present invention, in the paper feeding device according to the first aspect, the cleaning member can be raised beyond a paper conveyance height position.

  According to a third aspect of the present invention, in the paper feeding device according to the first aspect, the cleaning member moves from the paper stacking portion position (upper surface is the paper transport height position) immediately after the final paper feed to the time when there is no stacked paper. The paper stacking unit is temporarily raised so as to be positioned above the transport height position.

  According to a fourth aspect of the present invention, in the paper feeding device according to any one of the first to third aspects, the cleaning member is positioned above the paper conveyance height position immediately after the stacked paper is exhausted. The sheet stacking unit is operated so as to operate at least once between positions lower than the sheet conveyance height position.

  According to a fifth aspect of the present invention, in the paper feeding device according to any one of the first, third, and fourth aspects, the cleaning member is positioned above the paper conveyance height position immediately after the end of one image forming job. And the sheet stacking unit is operated so as to operate at least once between positions below the sheet conveyance height position.

  According to a sixth aspect of the present invention, in the paper feeding device according to any one of the third to fifth aspects, the operation in the upward direction from the paper conveyance height position and the cleaning operation in the downward direction therefrom, The moving speed of the paper stacking section is made faster than the moving speed at the time of normal paper feeding.

  According to a seventh aspect of the present invention, in the paper feeding device according to any one of the second to sixth aspects, the cleaning operation is performed only when a label sheet is passed.

  According to an eighth aspect of the present invention, in the paper feeding device according to any one of the first to seventh aspects, a cleaning liquid is supplied to the cleaning member, and a storage tank for the cleaning liquid is provided inside the paper stacking unit. It is characterized by that.

  According to a ninth aspect of the present invention, in the paper feeding device according to the eighth aspect of the present invention, the cleaning liquid is supplied to the cleaning member at an upper position than the sheet conveyance height position.

  According to a tenth aspect of the present invention, in the paper feeding device according to any one of the first to ninth aspects, the cleaning member can be replaced from the upper side of the paper stacking unit.

  According to an eleventh aspect, in the paper feeding device according to any one of the eighth to tenth aspects, the cleaning liquid can be replenished from an upper side of the paper stacking unit.

  According to a twelfth aspect of the present invention, in the paper feeding device according to any one of the first to eleventh aspects, there is provided means for notifying that the paper feeding operation cannot be performed during the cleaning.

  According to a thirteenth aspect of the present invention, in the paper feeding device according to any one of the first to twelfth aspects, the cleaning operation is performed for every certain amount based on the number of fed sheets.

  According to a fourteenth aspect of the present invention, in the paper feeding device according to any one of the first to thirteenth aspects, the cleaning member can freely move in and out in the width direction of the paper with respect to the paper stacking unit. And

  An image forming apparatus according to a fifteenth aspect uses the paper feeding device according to any one of the first to fourteenth aspects.

  According to the present invention, the height of the top surface of the stacked paper is set to a substantially constant position by the displacement of the paper stacking unit according to the paper stacking amount, and the paper is sequentially fed from the top surface paper. In the paper feeding device, a cleaning member is provided in the paper stacking portion, and the cleaning member is brought into contact with the inner wall surface of the side fence, so that dirt adhered to the inner wall surface of the side fence can be removed. improves.

  The best mode for carrying out the present invention will be described below with reference to the embodiments shown in the drawings.

  FIG. 1 is a diagram showing a first embodiment of the present invention. The plan view (FIG. 1A is abbreviated to show the front side (lower side in the figure) with respect to the center in the vertical direction in the figure. FIG. 1B is a front view and FIG. 1C is the right side. FIG.

  A sheet feeding device 2 is provided next to the illustrated image forming apparatus 1, and the sheets 3 are fed from the sheet feeding device 2 toward the image forming apparatus 1 one by one at a predetermined timing. The paper width direction is the center reference in the transport direction. The image forming apparatus 1 forms an image on the received paper 3 and discharges it. For example, the sheet feeding device 2 according to the present embodiment can load 4000 sheets of 0.11 mm thick paper 3. FIG. 1 shows a state immediately after 4000 sheets of paper 3 are stacked on the sheet stacking unit 7. It is a state diagram.

  Hereinafter, the configuration and operation of the sheet feeding device 2 will be described. The paper feeding device 2 mainly includes a paper stacking unit 4 and a paper feeding / conveying unit 5. The paper stacking unit 4 has a frame 6, and the paper feeding / conveying unit 5 is attached to the frame 6.

  The paper stacking unit 4 mainly includes a frame 6, a paper stacking unit 7 for stacking the paper 3 to be fed, a paper stacking unit lifting / lowering unit (not shown) that lifts and lowers the paper stacking unit 7 in a horizontal state, Photosensors 11A, 11B, and 11C for detecting the positions of the side fences 8 and 9 for holding and restricting both sides of the paper 3 in the paper feeding direction, the end fence 10 for holding and regulating the rear end of the paper transport direction, and the paper stacking unit 7. 11D and 11E. On the rear side of the paper stacking unit 7, a projection light shielding unit 7A for turning on the photosensors 11A to 11E is provided. Then, the upper and lower ends of the projection light-shielding part 7A shield the photosensor so that the height position of the paper stacking part 7, that is, the number of sheets 3 stacked can be known.

  On the other hand, the sheet feeding / conveying unit 5 mainly includes a pickup roller 12, a feed roller 13, a reverse roller 14, a conveyance roller 15, and a pickup roller 12 for feeding the sheet 3 stacked on the sheet stacking unit 7 from the uppermost sheet. Is composed of an actuator unit 16 (not shown) for moving up and down, a paper upper surface position control sensor unit 17 (not shown), and a paper end detection sensor unit 18 (not shown).

Hereinafter, description will be made focusing on the operation of the sheet stacking unit 7.
First, the sheet 3 loaded on the sheet stacking unit 7 is raised by a sheet stacking unit raising / lowering drive unit (not shown), and the uppermost surface position thereof is set at a substantially constant position by a sheet upper surface position control sensor unit 17 (not shown). It is controlled to be (3A position), and is fed and conveyed to the image forming apparatus 1 by a roller such as a pickup roller 12 (see FIG. 3). That is, the paper conveyance height position during paper feeding is always at a substantially constant height (3A position).

  By the way, since the 4000 sheets 3 can be stacked on the sheet stacking unit 7 as described above, the sheet stacking unit 7 is controlled between the sheet upper surface position control sensor unit 17 and the photo sensor 11E depending on the number of sheets 3 stacked. The position to be moved can be raised and lowered.

Here, it is assumed that the sensors 11A to 11E are arranged according to the following.
Sensor 11A: Arranged so that the cleaning member 20 is positioned above the uppermost sheet conveyance height position (3A position) (sheet loading section 7: L5 position)
Sensor 11B: A position where the remaining amount of paper is about 50 sheets. (Paper stacking unit 7: L3 position)
Sensor 11C: Near end position where the remaining amount of paper is about 500 sheets (paper stacking portion 7: L2 position)
Sensor 11D: Position where the remaining amount of paper is about 2000 sheets (paper stacking unit 7: L1 position)
Sensor 11E: position where 4000 sheets can be stacked (sheet stacking unit 7: L0 position)
FIG. 5 is a diagram when 2000 sheets are stacked on the sheet stacking unit 7.

  As shown in FIGS. 1 to 4, a cleaning unit 19 is attached to the paper stacking unit 7 so as to be adjustable in the paper width direction. The cleaning unit 19 includes a thick cleaning felt 20 and a holding bracket 21, and the cleaning felt 20 held by the holding bracket 21 comes into contact with the inner side surfaces 8 </ b> A and 9 </ b> A of the side fences 8 and 9. Yes. In the present embodiment, a thick felt is taken as an example of the cleaning member 20, but other materials having the same function such as a fired PUR can also be used. Further, in the explanatory diagram of the present embodiment, illustration is omitted, and the cleaning unit 19 is shown only in the rear side fence unit.

  The cleaning unit 19 is set to change the approximate position on the sheet stacking unit 7 according to each sheet width size. The elastic deformation portion 21A of the holding bracket 21 is provided with a convex portion 21B, and the paper stacking portion 7 is provided with a fine uneven portion 7B. By this combination, the protruding amount of the cleaning portion 19, in other words, The degree of contact of the cleaning felt 20 with the side fences 8 and 9 can be adjusted, and the cleaning performance can be kept constant. The cleaning unit 19 can be detached from the upper side.

  With such a configuration, immediately after the paper end detection sensor unit 18 (not shown) determines that there is no paper 3 (FIG. 6 corresponds, paper stacking unit 7: L4 position), the paper stacking unit 7 is It is raised until it is detected at 11A. That is, the upper surface of the cleaning felt 20 exceeds the paper transport height position (3A position) (this corresponds to FIG. 7).

  In the present embodiment, even if the paper stacking unit 7 is moved up to a position where the upper surface of the cleaning felt 20 exceeds the paper transport height position (3A position), the pickup roller 12 contacts the paper stacking unit 7 with the actuator unit 16. It is raised so as not to.

  Next, as shown in FIG. 8, the sheet stacking unit 7 is lowered to a position where the sensor 11B detects (a point where the sensor switches from ON to OFF). That is, it is lowered to a position below the 3A position. By this operation, the dirt adhered to the inner side surfaces 8A and 9A of the side fences 8 and 9 can be scraped off by the cleaning felt 20. In particular, the uppermost sheet conveyance height position (3A position) is apt to get dirty because the end face of the sheet is frequently rubbed against the side fence.

  In this example of the cleaning operation, the cleaning unit 19 is provided in the sheet stacking unit 7 and the sheet stacking unit 7 is moved. However, only the cleaning unit 19 may be moved by an actuator device (not shown). However, moving the paper stacking unit 7 as described above simplifies the component configuration and can easily achieve the object. As for the number of operations, the number of operations can be performed from 0 to a plurality of times according to the paper type information and the arbitrarily set value. That is, the cleaning performance can be changed depending on the number of operations.

  Furthermore, in this embodiment, the lower limit position of the sheet stacking unit 7 at the time of cleaning is set to the L3 position, but it may be set to lower L2 to L0 positions. After the above operation is completed, the sheet stacking unit 7 is lowered to the lowest limit position detected by the sensor 11E. Also at this time, the cleaning felt 20 continues to contact the inner wall surfaces 8A and 9A of the side fences 8 and 9, so that the adhered dirt can be scraped off. After the user replenishes the paper 3, the paper stacking unit 7 is lifted so that paper can be fed at any time. At this time, the dirt is scraped off.

  As another operation, for example, when the number of stacked sheets is small, such as when the sheet stacking unit 7 detects the sensor 11B, the cleaning operation may be performed for each image forming job. As a result, it is possible to more reliably remove stains attached to the inner wall surfaces (8A, 9A) of the side fence, particularly stains attached to the paper transport height position (3A). In addition, the above operation may be performed only when the label paper is passed and the adhesive (adhesive substance) 22 is easily attached to the inner wall surfaces of the side fences 8 and 9 (when inputting the paper type to the image forming apparatus). If the adhesive 22 adheres to the inner wall surfaces 8A and 9A of the side fence, this becomes a resistance when the next sheet is fed, and the sheet conveyance is delayed and a non-feed jam occurs).

  Thus, the cleaning operation can be performed only when the label paper is passed, and the downtime associated with cleaning can be eliminated for paper that does not require the cleaning operation.

  As described above, in the present embodiment, the paper stacking unit control is performed using the sensors 11A to 11E, but it can also be performed by pulse control using a stepping motor or the like without using the sensor.

  For example, there is a technique in which a PTFE (polytetrafluoroethylene) film 23 is attached to the inner wall surface of the side fence in order to prevent the label paper end surface adhesive from adhering to the side fences 8 and 9. Since PTFE is a non-adhesive material, it is difficult for the adhesive 22 to adhere to it. In such a case, as shown in FIG. 10, the adhesive 22 adhering to the contact of the cleaning felt 20 can be scraped off relatively easily.

  When the PTFE (polytetrafluoroethylene) film 23 is not attached to the inner wall surfaces 8A and 9A of the side fences 8 and 9, the adhesive 22 attached to the side fences is dry-cleaned when feeding the label paper. Felt is not easy to scrape.

  Therefore, as another embodiment of the present invention, an example in which the cleaning felt 20 is wetted with a cleaning liquid is shown below (already, FIGS. 1 to 9 are diagrams that reflect the wettability configuration).

  The cleaning unit 19 attached to the paper stacking unit 7 includes a cleaning liquid storage tank 24 in addition to the cleaning felt 20 and the holding bracket 21. In the cleaning liquid storage tank 24, ethanol (Ethanol) is stored as the cleaning liquid 25. The cleaning liquid storage tank 24 includes a valve portion 24A, a cam 24B provided integrally therewith, and a liquid supply lid 24C. The valve portion 24A can be brought into contact with and separated from the cleaning felt 20.

  As will be described later, since there is a state where the tank valve portion 24A and the cleaning felt 20 are in direct contact with each other, the supply of the cleaning liquid 25 is performed easily and efficiently. Since the liquid supply lid 24C can be opened from the upper side of the paper stacking unit 7, the replenishability of the cleaning liquid 25 is good. The cleaning liquid 25 is supplied to the cleaning felt 20 when the convex portion 8B, 9B provided on the side fences 8, 9 strikes the cam 24B when the sheet stacking portion rises to the vicinity of the L5 position. (When it is struck, it is in the state shown in FIG. 2). Of course, the cleaning liquid 25 can be supplied by other methods such as using an electric pump.

  With the above-described means, the cleaning liquid 25 is supplied above the paper conveyance height position (3A position), so that it is close to the uppermost paper conveyance position 3A and on the side fence inner wall surfaces (8A, 9A). It is possible to reliably remove the adhesive 22 that is largely adhered to the sheet conveying height position 3A.

  Although the supply of the cleaning liquid 25 is performed only from the L5 position this time, it is needless to say that the cleaning performance can be further improved by arbitrarily setting a plurality of positions. For example, in the example of the figure, it is also provided at the bottom. In addition, if the shape of the cam 24B is devised, it can be handled even in the middle in the height direction (for example, L1 position).

  The cleaning liquid 25 is not limited to ethanol as long as it can remove the adhesive (adhesive substance) and has quick drying properties.

  From the above, when the PTFE (polytetrafluoroethylene) film 23 is attached to the inner wall surfaces 8A and 9A of the side fence, the adhesive (adhesive substance) 22 can be more reliably used by using the cleaning liquid 25 as described above. Needless to say, can be removed.

  Further, in the present invention, when the cleaning operation is performed with the above-described configuration, the user is informed (by means such as display on the operation panel) that the sheet cannot be fed from the sheet feeding device. If so, the convenience for the user is not impaired. In addition, as a means to alert | report to a user, since a well-known and well-known means should just be employ | adopted, illustration and description are abbreviate | omitted.

  Further, as another cleaning method, if the cleaning operation is performed every certain amount based on the number of sheets fed from the sheet feeding device of the present invention, the number of cleaning operations (time) can be reduced. The user's convenience is not further impaired.

  Furthermore, if the vertical speed of the paper stacking unit 7 during the cleaning operation is made faster than during normal operation, the convenience for the user will not be further impaired. For example, as in the second embodiment, when the cam 24B is hit by the convex portions 8B and 9B provided on the side fences 8 and 9 and a certain amount of cleaning liquid 25 is automatically supplied, The faster the speed, the better.

  In addition, although the example in which the cleaning unit 19 is provided only on the downstream side in the transport direction of the side fences 8 and 9 has been described this time, cleaning may be performed over the entire transport direction. At that time, for example, the cleaning felt 20 may be elongated in the transport direction, or a plurality of cleaning units 19 may be installed. Alternatively, when a portion of the side fence that contacts the paper, such as a bead of a sheet metal or a convex portion of a plastic part, is set to be small, only that portion may be cleaned.

  Furthermore, in the present invention, the paper feeding device in which the paper stacking unit 7 moves up and down while maintaining a horizontal posture has been described. However, the paper feeding unit 7 is mainly used for a paper feeding tray of about 250 to 550 sheets. Needless to say, the present invention can also be applied to the paper stacking unit 7 that rotates.

  As described above, in the paper feeding device of the present invention, the paper stacking unit (in accordance with the stacking amount of the paper (3) is used for the purpose of removing dirt adhered to the inner wall surfaces (8A, 9A) of the side fence. 7) is displaced so that the height of the top surface of the stacked sheets is set to a substantially constant position (3A position), and the sheet stacking is performed in the sheet feeding device (2) that sequentially feeds from the top sheet. Since the cleaning member (20) is provided in the portion (7) and the cleaning member (20) is brought into contact with the inner wall surface (8A, 9A) of the side fence, dirt adhered to the inner wall surface (8A, 9A) of the side fence To be able to get rid of.

  Further, in order to remove the dirt attached to the inner wall surfaces (8A, 9A) of the side fence, in particular, to remove the dirt attached to the paper conveyance height position (3A position), a cleaning member ( 20) is raised above the paper transport height position (3A position), so that the dirt attached to the inner wall surfaces (8A, 9A) of the side fence is removed, especially the paper transport height position (3A position). Dirt adhered to the surface can be removed.

  Further, in order to achieve a simpler configuration to remove the dirt adhering to the paper conveyance height position (3A position) of the inner wall surface (8A, 9A) of the side fence, immediately after the last paper is fed, that is, no stacked paper is present. The paper stacking section (7) so that the cleaning member (20) is positioned above the paper transport height position (3A position) from the position of the paper stacking section (7) at the time (the upper surface is the paper transport height position 3A). Is once raised, it is possible to achieve removal of the dirt adhering to the sheet conveyance height position (3A position) of the inner wall surface (8A, 9A) of the side fence with a simpler configuration.

  Also, in order to more reliably remove dirt attached to the entire inner wall surface (8A, 9A) of the side fence, particularly dirt attached to the paper conveyance height position (3A), cleaning is performed immediately after the paper (3) is used up. The paper stacking unit (7) is configured so that the member (20) operates at least once between a position above the paper transport height position (3A position) and a position below the paper transport height position (3A position). Therefore, it is possible to more reliably remove dirt attached to the entire inner wall surface (8A, 9A) of the side fence, particularly dirt attached to the paper conveyance height position (3A).

  In addition, immediately after the end of one image forming job, in order to remove dirt attached to the entire inner wall surface (8A, 9A) of the side fence, particularly dirt attached to the paper conveyance height position (3A) frequently and more reliably, The paper stacking unit (7) is arranged so that the cleaning member (20) operates at least once between a position above the paper transport height position (3A position) and a position below the paper transport height position (3A position). ) Is operated, dirt on the entire inner wall surface (8A, 9A) of the side fence, particularly dirt attached to the paper transport height position (3A) can be more reliably removed.

  Further, in order to shorten the time during which the sheet feeding device cannot be used during the cleaning operation and to prevent the user's convenience from being impaired, the operation from the sheet conveyance height position (3A position) upward, and Since the moving speed of the paper stacking unit 7 during the downward cleaning operation is higher than that during normal paper feeding, the time during which the paper feeding device cannot be used during the cleaning operation is shortened. In addition, the convenience for the user can be prevented from being impaired.

  For paper that does not require a cleaning operation, it adheres to the inner wall surface (8A, 9A) of the side fence in order to eliminate the downtime associated with the cleaning operation, and on label paper that easily attaches an adhesive (adhesive substance) to the side fence. In order to reliably remove the adhesive, the cleaning operation is performed only when the label paper is passed, so that downtime associated with cleaning can be eliminated for paper that does not require cleaning operation. Moreover, in the label paper in which an adhesive (adhesive substance) is easily attached to the side fence, the adhesive adhered to the side fence inner wall surfaces (8A, 9A) can be surely removed.

  In addition, the cleaning liquid (25) can be supplied to the cleaning member (20) more easily and efficiently, and a PTFE (polytetrafluoroethylene) film can be applied to the inner wall surface (8A, 9A) of the side fence. Even if it is attached, the adhesive (adhesive substance) that adheres over time is surely removed to prevent the adhesive from resisting during paper feeding, delaying paper conveyance, and non-feed jams. Since the cleaning liquid (25) is supplied to the member (20) and the storage tank (24) is provided inside the paper stacking section (7), the cleaning liquid (25) is more supplied to the cleaning member (20). Even if it can be performed easily and efficiently, and a PTFE (polytetrafluoroethylene) film is attached to the inner wall surface (8A, 9A) of the side fence Since it is also time adhere to become adhesive to remove reliably (stickies), the adhesive becomes resistance during paper feeding, paper conveyance is delayed, it can be prevented from falling back to non feeding jam.

  Further, by supplying the cleaning liquid (25) during the actual cleaning operation, it is possible to prevent the cleaning liquid from drying, and thereby, the sheet conveyance height position (3A) on the inner wall surface (8A, 9A) of the side fence. In order to remove the adhesive (adhesive substance) (22) adhered to the cleaning member (22) more reliably, the cleaning liquid (25) is supplied to the cleaning member (20) above the paper transport height position (3A position). Therefore, the cleaning liquid (25) can be supplied during the actual cleaning operation, and the cleaning liquid does not dry out. Therefore, it adheres to the paper conveyance height position (3A) on the inner wall surface (8A, 9A) of the side fence. The removed adhesive (adhesive substance) (22) can be removed more reliably.

  Further, in order to improve the exchangeability of the cleaning member (20), the cleaning member (20) can be exchanged from the upper side of the paper stacking portion (7), so that the exchangeability of the cleaning member (20) can be improved. In order to improve the replenishability of the cleaning liquid (25), the cleaning liquid (25) can be replenished from the upper side of the paper stacking section (7), so that the replenishability of the cleaning liquid (25) can be improved. In order not to impair the convenience of the user during the cleaning, it is possible to eliminate the loss of the convenience of the user by notifying that the paper feeding operation cannot be performed during the cleaning.

  Further, in order to shorten the time during which the sheet feeding device cannot be used for the cleaning operation, and to avoid damaging the convenience of the user, a certain amount is determined based on the number of sheets fed from the sheet feeding device (2). Since the cleaning operation is performed for each amount, the time during which the paper feeding device cannot be used in the cleaning operation can be shortened, and the convenience for the user is not impaired.

  Further, in order to make the cleaning member (20) correspond to various paper size widths and to keep the cleaning performance constant, the cleaning member (20) can protrude and retract in the paper width direction with respect to the paper stacking portion (7). Therefore, it is possible to cope with various paper size widths, and the contact amount with respect to the side fences (8, 9) can be adjusted to be constant, so that the cleaning performance can be kept constant.

  Needless to say, the sheet feeding apparatus of the present invention as described above can be applied to various types of apparatuses in addition to the type of image forming apparatus as illustrated, and illustration and description thereof are omitted.

FIG. 4 is a diagram illustrating a first embodiment (position of the paper stacking portion L0) of the present invention. FIG. 2 is a partially enlarged view of FIG. 1 showing a second embodiment of the present invention. FIG. 1 is a diagram illustrating a state in which the sheet stacking unit operates (4000 sheets are stacked and immediately before sheet feeding) in the embodiment apparatus of FIG. The figure which shows Example 2 of this invention (partial enlarged view of FIG. 3). FIG. 1 is a diagram of a state where 2000 sheets are stacked on the sheet stacking unit in the embodiment apparatus of FIG. 1 (position of the sheet stacking unit L1). FIG. 1 is a diagram immediately after the paper end of the paper stacking unit (position of the paper stacking unit L4) in the embodiment apparatus of FIG. The figure which shows the state (paper stacking part L5 position) which raised the paper stacking part once from the state of FIG. The figure which shows the state (paper stacking part L3 position) which lowered | hung the paper stacking part slightly from the state of FIG. The figure which shows the detail (paper size change example) of Example 2 of this invention Figure of an example (example using PTFE film and no cleaning liquid) in which the adhesive adhering to the contact of the cleaning felt can be scraped off relatively easily.

Explanation of symbols

1: Image forming device 2: Paper feeding device 3: Paper 3A: Paper transport height position 4: Paper stacking unit 5: Paper feed transport unit 6: Frame 7: Paper stacking portion 7A: Projection light shielding portion 7B: Fine uneven portion 8: Front side fence 8A: Side fence inner wall surface 8B: Convex portion 9: Rear side fence 9A: Side fence inner wall surface 9B: Convex portion 10: End fences 11A to 11E: Paper stacking portion position detection sensor 12: Pickup roller 13: Feed roller 14: Reverse roller 15: Conveying roller 16: Actuator (not shown)
17: Paper upper surface position control sensor (not shown)
18: Paper end detection sensor (not shown)
19: Cleaning part 20: Cleaning felt 21: Holding bracket 21A: Elastic deformation part 21B: Convex part 22: Dirt, adhesive (adhesive substance)
23: PTFE film 24: Cleaning liquid storage tank 24A: Valve part 24B: Cam 24C: Liquid supply lid 25: Cleaning liquid L4 position: Paper stacking part 7 position immediately after last paper feeding

Claims (15)

In the paper feeding device in which the height of the top surface of the stacked paper is set to a substantially constant position and the paper is sequentially fed from the top surface paper by displacing the paper stacking unit according to the paper stacking amount.
A sheet feeding device, wherein a cleaning member is provided in the sheet stacking unit, and the cleaning member is brought into contact with an inner wall surface of a side fence positioned so as to sandwich the sheet stacking unit.   The sheet feeding device according to claim 1, wherein the cleaning member can be raised beyond a sheet conveyance height position.   The paper stacking portion is temporarily moved so that the cleaning member is positioned above the paper transport height position from the paper stack portion position (upper surface is the paper transport height position) immediately after the last paper is fed and when there is no stacked paper. The sheet feeding device according to claim 1, wherein the sheet feeding device is raised.   Immediately after there is no stacked paper, the cleaning member is operated so as to operate at least once between a position above the paper transport height position and a position below the paper transport height position. The sheet feeding device according to claim 1, wherein the sheet feeding device is operated.   Immediately after the end of one image forming job, the sheet stacking unit is configured so that the cleaning member operates at least once between a position above the sheet conveyance height position and a position below the sheet conveyance height position. The sheet feeding device according to claim 1, wherein the sheet feeding device is operated.   The moving speed of the paper stacking unit during the upward movement from the paper conveyance height position and the downward cleaning operation is higher than the movement speed during normal paper feeding. The paper feeding device according to any one of claims 3 to 5.   The paper feeding device according to claim 2, wherein the cleaning operation is performed only when label paper is passed.   The sheet feeding device according to claim 1, wherein a cleaning liquid is supplied to the cleaning member, and a storage tank for the cleaning liquid is provided inside the sheet stacking unit.   9. The sheet feeding device according to claim 8, wherein the supply of the cleaning liquid to the cleaning member is performed above the sheet conveyance height position.   The sheet feeding device according to claim 1, wherein the cleaning member is replaceable from above the sheet stacking unit.   The paper feeding device according to claim 8, wherein the cleaning liquid can be replenished from an upper side of the paper stacking unit.   12. The paper feeding device according to claim 1, further comprising a means for notifying that a paper feeding operation cannot be performed during the cleaning.   13. The sheet feeding device according to claim 1, wherein a cleaning operation is performed for each certain amount based on the number of sheets fed.   The sheet feeding device according to any one of claims 1 to 13, wherein the cleaning member can freely move in and out of the sheet stacking unit in a sheet width direction. An image forming apparatus using the paper feeding device according to claim 1.