JP6411192B2 - Paper conveying apparatus and image forming apparatus - Google Patents

Description

  The present invention relates to a sheet conveying apparatus and an image forming apparatus provided with a sheet conveying path for conveying a sheet.

  In general, an image forming apparatus that forms an image on a sheet is provided with a sheet conveying device that conveys the sheet. An actuator-type paper passing sensor is provided in the paper transport path to detect the paper jam in order to detect a paper jam and adjust the transport timing when transporting the paper. The actuator described above is configured to come into contact when the conveyed paper passes through, and exerts a load on the paper although it is a slight force. By the way, in the image forming apparatus, it is required to increase the processing speed, and accordingly, the conveyance speed of the paper is also increased. When the sheet is transported at a high speed, the influence of the load applied from the actuator becomes large, and the skew of the sheet that is transported in a tilted state becomes a problem. In order to solve such a problem, an image forming apparatus that corrects skew of a sheet has been proposed (for example, see Patent Document 1).

JP 2009-156991 A

  In the image forming apparatus described in Patent Document 1, a plurality of lever members (an example of an actuator) that swing in contact with a sheet are provided in a sheet conveyance path between the transfer unit and the fixing unit. The plurality of lever members are juxtaposed in a direction orthogonal to the sheet conveying direction, and each operate independently. In the image forming apparatus described above, the skew of the sheet is corrected by decelerating the leading edge on the side conveyed in advance by the plurality of lever members arranged in parallel and conveying the other leading edge without delay. Yes.

  In the above-described image forming apparatus, the sheet is brought into contact with the preceding lever member and further brought into contact with the other lever member so that the impact when the sheet comes into contact is different. By the way, there are a plurality of lever members, and it is necessary to align the positions in the sheet conveying direction. When a new lever member is provided at a different position in the sheet conveying direction, a plurality of new lever members are also arranged in parallel. There must be.

  Usually, in an image forming apparatus, various apparatuses are arranged in a sheet conveyance path, and a sufficient distance is required in the sheet conveyance direction. For this reason, it is not sufficient to provide the lever member only in a short section between the transfer section and the fixing section, and other sections need to be considered. Therefore, in the image forming apparatus described in Patent Document 1, since a plurality of lever members are provided, there is a concern that the structure is complicated and the cost is high, and it is not possible to suppress the skew of the sheet with a simple configuration. There is.

  SUMMARY An advantage of some aspects of the invention is that it provides a sheet conveyance device and an image forming apparatus that can prevent sheet skew and improve conveyance accuracy.

Sheet conveying apparatus according to the present invention, there is provided a sheet conveying apparatus having a sheet conveying path for conveying paper, wherein the paper transport path, a plurality of levers in contact with the leading end of the sheet to be conveyed is provided, wherein in the width direction of the sheet, the to center line of the sheet, on one side a first side, when the other side is a second side, said plurality of levers, I along the conveying direction of the sheet, the are arranged alternately in the second side to the first side, between the second side lever disposed on the first side lever second side disposed on the first side, the distance from the center line The first side lever and the second side lever are different from each other in lever load, which is a load on the sheet in contact with the first side lever .

In the paper transport device according to the present invention, the first side lever is disposed at a position where the distance from the center line is shorter than the second side lever, and the lever load at the first side lever is the second lever. It is good also as a structure set larger than the lever load in a side lever .

In the paper conveying apparatus according to the present invention, the first side lever and the second side lever may be arranged so that a product of a distance from the center line and the lever load is substantially equal. .

  In the paper transport device according to the present invention, the plurality of levers are configured to swing in a direction in which they are separated from and contacting the paper, and each includes a biasing member that biases the plurality of levers to swing. It is good also as composition which has.

In the paper transport device according to the present invention, the paper transport device includes a registration roller that is provided in the paper transport path and receives the leading edge of the paper, and the plurality of levers are located between the upstream side in the transport direction and the registration roller . The same number of levers may be provided on the first side and the second side .

  The paper transport device according to the present invention may include a paper detection sensor that detects the paper position based on the plurality of levers contacting the paper.

  In the paper transport device according to the present invention, the paper transport device includes a roller that is provided in the paper transport path and transports the paper, and among the plurality of levers, adjacent levers in the transport direction sandwich the roller in the transport direction. It is good also as a structure provided in.

  An image forming apparatus according to the present invention includes the sheet conveying device according to the present invention.

According to the present invention, since the plurality of levers are alternately arranged across the center line , the load can be distributed in the width direction and balanced. As a result, the conveyance speed of the paper is adjusted so that only one side does not become faster, and the skew of the paper can be prevented and the conveyance accuracy can be improved.

1 is a schematic side view of an image forming apparatus according to an embodiment of the present invention. FIG. 2 is a schematic side view showing an enlargement of a document conveying unit and an image reading unit shown in FIG. 1. It is an expanded sectional view which extracts and shows a roller and a lever. It is a principal part enlarged view which shows the roller and lever which were seen from the inner surface side of the 1st conveyance guide of FIG. It is a principal part enlarged view which shows the roller and lever which were seen from the outer surface side of the 1st conveyance guide of FIG. FIG. 6 is an enlarged cross-sectional view illustrating a state where a sheet contacts a lever. It is explanatory drawing which shows the positional relationship of the reference line set with respect to the width direction, and a lever. It is explanatory drawing which shows the positional relationship of the reference line and lever in a comparative example. FIG. 5 is an explanatory diagram illustrating a positional relationship between a sheet and a lever in the sheet conveying device according to the first embodiment of the present invention. It is explanatory drawing which shows the positional relationship of the paper and lever in the paper conveying apparatus which concerns on 2nd Embodiment of this invention. FIG. 10 is an explanatory diagram illustrating a positional relationship between a sheet and a lever in a sheet conveying device according to a third embodiment of the present invention.

  Hereinafter, an image forming apparatus according to an embodiment of the present invention will be described with reference to the drawings.

  FIG. 1 is a schematic side view of an image forming apparatus according to an embodiment of the present invention.

  The image forming apparatus 100 has a copying function of reading a document and forming an image on a sheet. The image forming unit 100 includes an image reading unit 90, a document conveying unit (ADF) 120 provided above the image reading unit 90, and an image reading unit 90. An apparatus main body 110, a paper feed cassette 81, a manual paper feed cassette 82, and a stacking tray 83 are provided on the lower side.

  The document conveying unit 120 is supported to be openable and closable with respect to the image reading unit 90. When the document conveying unit 120 is opened, the document placing glass 91 provided above the image reading unit 90 is opened so that the document can be placed manually. The document transport unit 120 automatically transports the placed document onto the image reading unit 90 via the document transport path Sb (for details, see FIG. 2). The image reading unit 90 reads the placed document or the document transported from the document transport unit 120 and generates image data. The document conveying unit 120 and the image reading unit 90 will be described in detail with reference to FIG.

  In the image forming apparatus 100, image data corresponding to a color image using each color of black (K), cyan (C), magenta (M), yellow (Y), or a monochrome image using a single color (for example, black). Are treated. The apparatus main body 110 is provided with four each of a developing device 2, a photosensitive drum 3, a drum cleaning device 4, and a charger 5 for forming four types of toner images, each of which includes black, cyan, magenta, and There are four image stations associated with yellow.

  The drum cleaning device 4 removes and collects residual toner on the surface of the photosensitive drum 3. The charger 5 uniformly charges the surface of the photosensitive drum 3 to a predetermined potential. The optical scanning device 1 exposes the surface of the photosensitive drum 3 to form an electrostatic latent image. The developing device 2 develops the electrostatic latent image on the surface of the photosensitive drum 3 to form a toner image on the surface of the photosensitive drum 3. Through the above-described series of operations, a toner image of each color is formed on the surface of each photosensitive drum 3.

  An intermediate transfer belt 61 of the intermediate transfer belt unit 6 is disposed on the upper side of the photosensitive drum 3. The intermediate transfer belt 61 is stretched around the transfer belt driving roller 62 and the transfer belt driven roller 63, and moves around. The belt cleaning device 65 removes and collects residual toner, and is formed on the surface of each photosensitive drum 3. The toner images of the respective colors are sequentially transferred and superposed to form a color toner image on the surface of the intermediate transfer belt 61.

  A nip area is formed between the transfer roller 10 and the intermediate transfer belt 61, and the sheet conveyed through the recording sheet conveyance path Sa (an example of the sheet conveyance path S) is sandwiched and conveyed in the nip area. When the recording paper passes through the nip area, the toner image on the surface of the intermediate transfer belt 61 is transferred and conveyed to the fixing device 7.

  The fixing device 7 includes a fixing roller 71 and a pressure roller 72 that rotate with a recording sheet interposed therebetween. The fixing roller 71 is heated by a heating unit 73 provided outside. The fixing device 7 sandwiches the recording paper on which the toner image is transferred between the fixing roller 71 and the pressure roller 72 and heats and presses the recording paper to fix the toner image on the recording paper.

  The paper feed cassette 81 is a cassette for storing recording paper used for image formation, and is provided below the optical scanning device 1. The recording paper accumulated in the paper feed cassette 81 is pulled out from the paper feed cassette 81 by the pickup roller 11a. The manual paper feed cassette 82 is provided on the side surface of the apparatus main body 110 so as to be openable and closable. A recording paper can be placed by opening the manual paper feed cassette 82. The recording paper accumulated in the manual paper feed cassette 82 is pulled out by the pickup roller 11b.

  The apparatus main body 110 is provided with a paper transport device 111 in the recording paper transport path Sa. The paper transport device 111 serves as a roller 30 for sandwiching and transporting the recording paper, and a transport roller 12a to transport roller 12d, and a resist. And a plurality of levers 20 are provided. The structures of the roller 30 and the lever 20 will be described in detail with reference to FIGS. 3 to 4B described later. For the sake of explanation, the upstream side in the transport direction H is abbreviated as the upstream side and the downstream side in the transport direction H with respect to the recording paper transport direction H in the recording paper transport path Sa (see FIG. 3 described later). Sometimes abbreviated as downstream.

  The registration roller 13 is provided on the upstream side of the transfer roller 10, temporarily stops the recording paper, aligns the leading edge of the recording paper, and then adjusts the color in the nip area between the intermediate transfer belt 61 and the transfer roller 10. The conveyance of the recording paper is started in accordance with the transfer timing of the toner image. The conveyance roller 12 a is disposed on the downstream side of the pickup roller 11 a and the pickup roller 11 b and on the upstream side of the registration roller 13. That is, the two recording paper transport paths Sa that pass through the pickup roller 11a or the pickup roller 11b merge into one through the transport roller 12a and are guided to the registration roller 13. The conveyance roller 12b is disposed on the downstream side of the fixing device 7, and the recording paper is discharged to the stacking tray 83 via the conveyance roller 12b. The recording paper transport path Sa includes a reverse transport path Sar that guides the recording paper to the registration roller 13 again after passing through the fixing device 7, and the transport roller 12c and the transport roller 12d are arranged in the reverse transport path Sar. Has been. When performing image formation not only on the front side of the recording paper but also on the back side, after forming the image on the front side, the reverse side of the recording paper is reversed via the reverse conveyance path Sar, so that the back side is the same as the front side. Image formation can be performed.

  The apparatus main body 110 is provided with four levers 20. The lever 20 is provided between the pickup roller 11a and the conveyance roller 12a, between the conveyance roller 12a and the registration roller 13, and between the conveyance roller 12d and the registration roller 13. And between the transport roller 12c and the transport roller 12d.

  FIG. 2 is an enlarged schematic side view showing the document conveying section and the image reading section shown in FIG.

  The document transport unit 120 includes a document tray 122 on which a document is placed, a discharge tray 123 from which a document is discharged, and a document transport path Sb (an example of a sheet transport path S) through which the document is transported. In the document transport path Sb, the paper transport device 121 takes in the document placed on the document tray 122 and transports it to the discharge tray 123. In the following description, for the sake of explanation, the recording paper conveyed in the recording paper conveyance path Sa and the original conveyed in the original conveyance path Sb may be collectively referred to as paper P. In other words, the document is pre-formed with an image read by the image reading unit 90, whereas the recording paper differs in that the image is formed by the apparatus main body 110. Are common in that they are plain paper, cardboard, postcards and other paper. In the document transport path Sb, in the document transport direction H, the document tray 122 side may be referred to as an upstream side, and the discharge tray 123 side may be referred to as a downstream side.

  In the document transport path Sb, as a roller 30 that sandwiches and transports the document, the document pickup roller 14, the document separation roller 15, the first document transport roller pair 16a, the second document transport roller pair 16b, A three document transport roller pair 16c, a document discharge roller pair 17 and a document discharge roller pair 18 are arranged. The document pickup roller 14 takes in the document placed on the document tray 122 into the document transport unit 120 in order from the top. The document separation roller 15 prevents a plurality of documents from being transported to the document transport path Sb in a state where they overlap (multiple feeding). The first document transport roller pair 16a, the second document transport roller pair 16b, and the third document transport roller pair 16c sandwich and transport the document. The document passes over the document reading glass 92 between the second document transport roller pair 16b and the third document transport roller pair 16c. The pre-document discharge roller pair 17 includes two rollers, and one of the rollers is in contact with and away from the other roller. The document is discharged to the discharge tray 123 via the document discharge roller pair 18. A document reversing path Sbr is provided between the pre-document discharge roller pair 17 and the first document transport roller pair 16a. When reading both sides of the document, the document transported to the document discharge roller pair 18 is returned to the first document transport roller pair 16a via the document reversing path Sbr with the rear end switched to the leading end. That is, the document reversing path Sbr has a function similar to that of the reversing conveyance path Sar of the recording paper conveyance path Sa.

  The document conveying unit 120 is provided with four levers 20. The lever 20 is provided between the document separating roller 15 and the first document conveying roller pair 16 a, and between the first document conveying roller pair 16 a and the second document conveying roller. They are disposed between the pair 16b, between the second document conveying roller pair 16b and the document reading glass 92, and between the document reading glass 92 and the third document conveying roller pair 16c.

  The image reading unit 90 includes a document placing glass 91, a document reading glass 92, a light source unit 93, a mirror unit 94, and an imaging unit 95, and performs reading by a document fixing method and reading by a document moving method. Specifically, the image reading unit 90 is provided with a document placing glass 91 and a document reading glass 92 on the upper surface, and has a light source unit 93, a mirror unit 94, and an imaging unit 95 inside.

  The document placing glass 91 and the document reading glass 92 are transparent glass plates, and are configured to transmit light emitted from the light source unit 93 and transmit light reflected by the document. The light source unit 93 emits light toward the document and guides the light reflected by the document to the mirror unit 94. The light source unit 93 is configured to move below the document placement glass 91 and the document reading glass 92. The mirror unit 94 is configured to move in conjunction with the light source unit 93. The mirror unit 94 reflects the light guided from the light source unit 93 and makes it incident on the imaging unit 95. The imaging unit 95 includes a condenser lens, a CCD (Charge Coupled Device), and the like, and images reflected light from the mirror unit 94 on the CCD to capture an image of the document.

  In the image reading unit 90, the light source unit 93 is moved along the document placement glass 91 when reading by the document fixing method. In the image reading unit 90, when reading by the document moving method, the light source unit 93 is stopped below the document reading glass 92, and the document is transported by the document transporting unit 120 so as to pass above the document reading glass 92. Let

  Next, the roller 30 and the lever 20 provided in the image forming apparatus 100 will be described in detail. In the image forming apparatus 100, a plurality of rollers 30 and levers 20 are provided in the paper transport path S (the recording paper transport path Sa and the document transport path Sb). Hereinafter, although an example of the roller 30 and the lever 20 will be described, the details of the rollers 30 and the lever 20 may be different.

  FIG. 3 is an enlarged cross-sectional view showing the roller and the lever extracted, and FIG. 4A is an enlarged view of a main part showing the roller and the lever as seen from the inner surface side of the first conveyance guide of FIG. 4B is an enlarged view of a main part illustrating the roller and the lever as viewed from the outer surface side of the first conveyance guide in FIG. 3. In FIG. 4B, the second conveyance guide 52 and the counter roller 40 are omitted, and a part of the lever 20 is shown in consideration of the visibility of the drawing.

  As shown in FIG. 3, the sheet conveyance path S is provided with a first conveyance guide 51 and a second conveyance guide 52 that are arranged to face each other, and the sheet P is conveyed with the first conveyance guide 51 and the second conveyance guide. It is conveyed in the area sandwiched between the outer surfaces of the guide 52. The roller 30 and the lever 20 are provided on the inner side surface 51a side of the first conveyance guide 51 (in FIG. 3, below the first conveyance guide 51). A counter roller 40 is provided on the inner surface side of the second conveyance guide 52 at a position corresponding to the roller 30, and the counter roller 40 and the roller 30 (in particular, the rotating body 31) are in contact with each other.

  As illustrated in FIG. 4A, the roller 30 includes a rotating body 31, a roller support shaft 32, and a bearing 33. Three rotating bodies 31 are fixed to the roller support shaft 32 so as to be separated from each other, and are rotatably supported by the image forming apparatus 100 via bearings 33 provided at both ends. The first conveyance guide 51 is provided with a roller hole 51d at a position corresponding to the rotator 31, and the rotator 31 protrudes toward the outer surface 51b through the roller hole 51d. In addition, although detailed description is abbreviate | omitted about the opposing roller 40, what is necessary is just to make it the structure supported rotatably by the axis | shaft similarly to the roller 30. FIG. Further, one of the roller 30 and the counter roller 40 is configured to rotate by a drive source (not shown) and the other is driven. Hereinafter, for the sake of explanation, in the width direction of the paper P, the direction toward the one end (first end E1) of the paper P (the left direction in FIG. 4B) is referred to as the first width direction W1, and the other side of the paper P The direction toward the end (second end E2) (right direction in FIG. 4B) may be referred to as a second width direction W2.

  As shown in FIG. 4A, the lever 20 includes a lever swinging portion 21, a lever support shaft 22, a detected portion 23, a biasing fixing portion 24, and a biasing member 25. One end of the lever swing portion 21 is fixed to the lever support shaft 22, and a swing contact portion 21 a is provided at the other end. The lever support shaft 22 is rotatably supported by the image forming apparatus 100 via a housing (not shown). The swing contact portion 21 a is formed in a rod shape extending from the inner side surface 51 a side to the outer side surface 51 b side of the first conveyance guide 51, and the outer side surface through a lever hole 51 c formed in the first conveyance guide 51. Projecting to the 51b side. The urging fixing portion 24 is formed so as to protrude from the lever support shaft 22. The urging member 25 is, for example, a torsion coil spring, the coil portion is wound around the lever support shaft 22, one end is fixed to the urging fixing portion 24, and the other end is fixed to a housing (not shown). Has been. The detected portion 23 is extended from one end fixed to the lever support shaft 22, and a detected protrusion 23 a is provided at the other end.

  As shown in FIG. 4A, the lever hole 51c is provided near the second end E2 of the paper P. The positional relationship between the lever 20 and the paper P in the width direction will be described in detail with reference to FIG.

  A paper detection sensor 26 is provided in the vicinity of the detected protrusion 23a. The paper detection sensor 26 is an optical sensor, for example, and irradiates light between the light transmitting / receiving unit 26a and detects whether or not the light is blocked by the detected protrusion 23a. In addition, in the state shown in FIG. 3, the to-be-detected protrusion part 23a is located below the light transmission / reception part 26a, and is not shielding between light transmission / reception parts 26a.

  The lever support shaft 22 is urged by the urging member 25, and rotates in the direction of the arrow Y1 (counterclockwise in FIG. 3). The rotation of the lever support shaft 22 stops when the lever swinging portion 21 comes into contact with the first conveyance guide 51. Due to the rotation of the lever support shaft 22, the swing contact portion 21 a swings and protrudes from the lever hole 51 c to block the paper transport path S.

  FIG. 5 is an enlarged cross-sectional view showing a state in which the paper is in contact with the lever.

  In FIG. 5, the paper P is transported in the transport direction H with respect to the state shown in FIG. 3. Since the paper P is transported in the transport direction H, the leading edge Pa passes through the lever 20 (particularly, the swinging contact portion 21a) and is sandwiched between the roller 30 and the opposing roller 40. The swing contact portion 21a is pushed down by the paper P toward the inner side surface 51a. The lever support shaft 22 rotates in the direction of the arrow Y2 (clockwise in FIG. 5) against the urging force of the urging member 25 as the swinging contact portion 21a is pushed down, and the detected portion 23 also rotates in accordance with the lever support shaft 22. As a result, the light-transmitting / receiving section 26a is shielded by the detected protrusion 23a, and the paper detection sensor 26 detects that the paper P has contacted the lever 20. That is, by detecting the position of the paper P by the paper detection sensor 26, it can be determined whether or not the paper P is being conveyed smoothly.

  When the paper P is further transported in the transport direction H from the state shown in FIG. 5 and the rear end of the paper P passes through the lever 20 (swinging contact portion 21a), the lever support shaft 22 is moved to the biasing member 25. Energized and rotated in the direction of arrow Y1, returns to the state shown in FIG. As described above, the plurality of levers 20 are configured to swing in the direction of separating from and contacting the paper P, and are each provided with a biasing member 25 that biases the plurality of levers 20 to swing. In other words, by providing the urging member 25, the lever 20 that comes in contact with the paper P can be obtained without a complicated structure.

  In FIG. 3, the first conveyance guide 51 and the second conveyance guide 52 are formed in a straight line shape, but are not limited to this, and have a curved shape according to the internal structure of the image forming apparatus 100. Also good. The paper P is transported along the first transport guide 51 and the second transport guide 52 and is set to a transport direction H according to the shape of the first transport guide 51 and the second transport guide 52. Moreover, although the structure which provided the lever 20 in the inner surface 51a side of the 1st conveyance guide 51 was shown, it is not limited to this, You may provide the lever 20 in the inner surface side of the 2nd conveyance guide 52. Furthermore, although the three rotary bodies 31 were provided in the roller 30, the number of the rotary bodies 31 should just be set suitably.

  As described above, the torsion coil spring is used as the biasing member 25. However, the present invention is not limited to this, and the lever support shaft 22 is rotated in the direction of the arrow Y1 so that the swing contact portion 21a is moved to the sheet transport path S. Any spring may be used as long as it protrudes to the side, and a spring or a weight may be used. The presence or absence of the paper detection sensor 26 can be selected as appropriate, and the lever 20 without the paper detection sensor 26 may be provided.

  Next, the position of the lever 20 in the width direction will be described in detail. In the image forming apparatus 100, a reference line KS parallel to the conveyance direction H of the paper P is set, and the position of the lever 20 is determined based on the reference line KS. Therefore, the position of the lever 20 with respect to the reference line KS will be described with reference to FIGS. 6 and 7 in comparison with a comparative example according to a conventional structure.

  FIG. 6 is an explanatory diagram showing a positional relationship between a reference line set in the width direction and the lever.

  FIG. 6 shows a part of the sheet conveyance path S, and the three levers 20 and the three rollers 30 are extracted. However, the present invention is not limited to this, and other members are provided between these members. Also good. Further, the number of levers 20 and rollers 30 may be different as long as they are different portions of the sheet conveyance path S.

  In the paper transport path S, the paper P is transported across the reference line KS in the width direction. That is, one end portion (first end E1) of the sheet P is located on the side in the first width direction W1 (left side in FIG. 6) from the reference line KS, and the other end portion (second end) of the sheet P. E2) is located on the second width direction W2 side (right side in FIG. 6) from the reference line KS.

  The levers 20 and the rollers 30 are alternately arranged in order from the upstream side in the transport direction H. Hereinafter, in order to distinguish the lever 20 and the roller 30, the lever 20 is referred to as a first lever 20a, a second lever 20b, and a third lever 20c in order from the upstream side, and the roller 30 is sequentially referred to from the upstream side. They are called 1 roller 30a, 2nd roller 30b, and 3rd roller 30c. The first lever 20a is provided at a position (second end E2 side) shifted in the second width direction W2 (rightward in FIG. 6) from the reference line KS, and the second lever 20b is from the reference line KS. The third lever 20c is provided at a position shifted in the first width direction W1 (leftward in FIG. 6) (on the first end E1 side), and the third lever 20c is shifted from the reference line KS in the second width direction W2. Is provided.

  As described above, the plurality of levers 20 are alternately arranged on the first end E1 side and the second end E2 side in the order along the transport direction H. That is, when the lever 20 is further provided on the downstream side of the third lever 20c, the lever 20 may be disposed first on the first end E1 side and then on the second end E2 side.

  FIG. 7 is an explanatory diagram showing the positional relationship between the reference line and the lever in the comparative example.

  As in FIG. 6, the comparative example shows three levers and three rollers arranged alternately. Hereinafter, in order to distinguish each lever and roller, the lever is referred to as a first comparison lever 220a, a second comparison lever 220b, and a third comparison lever 220c in order from the upstream side, and the roller is first in order from the upstream side. These are called the comparison roller 230a, the second comparison roller 230b, and the third comparison roller 230c. In the comparative example, the first comparison lever 220a, the second comparison lever 220b, and the third comparison lever 220c are provided at positions shifted from the reference line KS in the first width direction W1 (leftward in FIG. 7). .

  In the comparative example, the plurality of levers are all arranged near one end in the width direction. Therefore, the lever contacts only one end side of the sheet. As a result, there is a risk that the sheet is subjected to a load only on one end side and the conveyance speed is reduced, causing skew and the like. On the other hand, in the present embodiment, since the plurality of levers 20 are alternately arranged across the reference line KS, the load can be distributed in the width direction and balanced. As a result, the conveyance speed of the paper P is adjusted so that only one end side does not become fast, and the skew of the paper P can be prevented and the conveyance accuracy can be improved.

  The sheet conveying apparatus (the sheet conveying apparatus 111 and the sheet conveying apparatus 121) according to the present invention includes three embodiments based on the position of the lever 20 with respect to the sheet P. Hereinafter, the positional relationship between the paper P and the lever 20 in the paper transport device according to the first to third embodiments will be described with reference to the drawings. In FIG. 8 to FIG. 10 shown below, a plurality of sheets P having different sizes are overlapped, and each sheet P is shown in perspective in consideration of easy viewing of the drawings.

  FIG. 8 is an explanatory diagram showing the positional relationship between the paper and the lever in the paper transport device according to the first embodiment of the present invention.

  The paper transport device corresponds to the sizes of a plurality of papers P. In FIG. 8, A3 paper A3, A4 paper A4R, horizontal A4 paper A4, and A5 paper A5R are used as paper P used in the paper transport device. It is shown. The A3 paper A3 is an “A3” size paper P, the A4 paper A4R is an “A4” size paper P, and the A5 paper A5R is an “A5” size paper P. The A3 paper A3, A4 paper A4R, and A5 paper A5R are “longitudinal” in which the long sides are arranged in parallel with the reference line KS. The landscape A4 sheet A4 is an “A4” size sheet P and is “landscape” in which the short sides are arranged in parallel with the reference line KS. The A3 paper A3, A4 paper A4R, horizontal A4 paper A4, and A5 paper A5R are conveyed such that the center line in the width direction coincides with the reference line KS.

  FIG. 8 shows four levers 20 arranged in the transport direction H. In order to distinguish them, the first lever 20a, the second lever 20b, the third lever 20c, and the fourth lever are sequentially arranged from the upstream side. Call 20d. The first lever 20a and the third lever 20c are provided at a position (first end E1 side) shifted in the first width direction W1 (leftward in FIG. 8) from the reference line KS, and the second lever 20b and the fourth lever The lever 20d is provided at a position (second end E2 side) shifted in the second width direction W2 (rightward in FIG. 8) from the reference line KS.

  The four levers 20 are provided at positions where distances from the reference line KS in the width direction (first lever width LW1) are substantially equal. Specifically, the first lever width LW1 is about 23 mm. In the present embodiment, since the levers 20 are arranged on both ends so as to sandwich the center line of the paper P, the load on the paper P can be more evenly distributed. Further, by arranging the lever 20 at a position where the distance from the reference line KS is equal, the load exerted on the paper P on the first end E1 side and the second end E2 side is made even, and the inclination of the paper P is further prevented. be able to.

  By the way, when the lever is provided at a position coincident with the center line of the paper, it seems that the load is not biased. However, in this case, a new problem may occur. In recent years, as part of environmental measures, resource recycling and the like have been promoted, and the image forming apparatus is also required to cope with it. Therefore, in the image forming apparatus, the paper is reused, but punched holes may be formed in the used paper for filing or the like. The positions where the punch holes are formed are determined according to the number of sheets to be provided, the size of the paper, and the like. When an odd number of punch holes are provided, the punch holes may be formed at positions that coincide with the center line of the paper. When the used paper is transported, if the lever comes into contact with the punch hole, the lever may be caught in the punch hole, and the transport of the paper may be hindered. Therefore, it is desirable to provide the lever at a position separated from the center line of the paper. Further, the positions where general punch holes are formed are set according to international standards and the like, and it is desirable to provide a lever so as to avoid those positions.

  As described above, it is desirable that the levers 20 adjacent to each other in the transport direction H among the plurality of levers 20 are provided so as to sandwich the roller 30 in the transport direction H. For example, as shown in FIG. 1, in the apparatus main body 110, the conveyance roller 12 a and the conveyance roller 12 d are disposed between the levers 20. Further, as shown in FIG. 2, in the document conveying section 120, the first document conveying roller pair 16 a and the second document conveying roller pair 16 b are disposed between the levers 20. That is, the roller 30 is provided between the levers 20, and the levers 20 are separated from each other in the transport direction H. Accordingly, the plurality of levers 20 are arranged over a wide range in the transport direction H, and can be configured to prevent the skew of the paper P over a wide range. In addition, since the roller 30 is provided between the levers 20 adjacent in the transport direction H, it is possible to grasp the transport status of the paper P by detecting which lever 20 the paper P has reached. it can.

  The plurality of levers 20 are preferably provided with the same number of levers 20 on the first end E1 side and the second end E2 side between the upstream side in the transport direction H and the registration roller 13. That is, if the number of levers 20 provided on the first end E1 side and the second end E2 side is the same, the load applied to the paper P is adjusted, and oblique feeding that cannot be corrected by the registration roller 13 is prevented in advance. it can. If the inclination of the paper P is slight, it can be easily corrected by the registration roller 13, and the positional accuracy of the paper P when transferred by the transfer roller 10 can be improved. In the present embodiment, as shown in FIG. 1, the apparatus main body 110 reaches the registration roller 13 via the two levers 20 via the pickup roller 11a. Further, in the reverse conveyance path Sar, it reaches the registration roller 13 via the two levers 20. Further, as shown in FIG. 2, in the document conveying unit 120, the second document conveying roller 16 b receives the leading edge Pa of the sheet P and corrects the inclination, and the sheet P when the image is read by the document reading unit 90. Is prevented.

  FIG. 9 is an explanatory diagram showing the positional relationship between the paper and the lever in the paper transport device according to the second embodiment of the present invention. In addition, about the component which a function is substantially equal to 1st Embodiment, the same code | symbol is attached | subjected and description is abbreviate | omitted.

  The second embodiment differs from the first embodiment in the distance from the reference line KS in the width direction of the lever 20. As in the first embodiment, the paper P is transported such that the center line in the width direction coincides with the reference line KS.

  As in the first embodiment, the plurality of levers 20 are alternately arranged across the reference line KS, and the first lever 20a and the third lever 20c are distances from the reference line KS in the width direction (first 1 lever width LW1) is also the same as in the first embodiment. The second lever 20b and the fourth lever 20d are different from the first lever 20a and the third lever 20c in the distance from the reference line KS in the width direction (second lever width LW2). The lever width LW2 is about 46 mm. As described above, the lever 20 can be arranged at different positions of the paper P on the first end E1 side and the second end E2 side, and the degree of freedom in designing the position of the lever 20 can be improved.

  In the plurality of levers 20, a lever load is preset for each lever as a load on the contacted paper, and the distance from the reference line KS in the width direction (first lever width LW 1 or second lever width LW 2) and the lever. Each lever is arranged so that the product with the load is substantially equal. Specifically, the first lever width LW1 is smaller than the second lever width LW2, and the first lever 20a and the third lever 20c are provided closer to the reference line KS than the second lever 20b and the fourth lever 20d. Therefore, the lever load is set large. In this way, by setting the lever load, the moment applied to the paper P can be adjusted, and the influence on the paper P can be made constant regardless of the position where the lever 20 is provided. As a result, the skew of the paper P can be prevented more reliably.

  The lever load is adjusted by the urging force of the urging member 25. For example, when the urging member 25 is a torsion coil spring, the urging force is different between the first end E1 side and the second end E2 side by using different urging members 25 such as thickness and length. It can be configured.

  The method of adjusting the lever load is not limited to the urging member 25, and a difference may be provided in the weight of the urging fixing portion 24 (see FIG. 4A). In this case, the lever support shaft 22 may be rotated by the weight of the urging fixing portion 24 and the urging member 25 may not be provided. Specifically, the length of the biasing fixing portion 24 may be different between the first end E1 side and the second end E2 side, and a difference in weight may be provided, or the biasing fixing portion 24 itself (particularly, , The tip) may have different weights. When the weight is attached to the urging fixing portion 24, the distance from the center of the lever support shaft 22 to the weight is different on the first end E1 side and the second end E2 side, so that the lever load is reduced. Adjust it.

  FIG. 10 is an explanatory diagram showing the positional relationship between the paper and the lever in the paper transport device according to the third embodiment of the present invention. In addition, about the component which a function is substantially equal to 1st Embodiment and 2nd Embodiment, the same code | symbol is attached | subjected and description is abbreviate | omitted.

  In the first embodiment and the second embodiment, the paper P having different sizes is conveyed with the center line aligned in the width direction, whereas in the third embodiment, the end in the width direction is provided. They are transported together. Specifically, in the third embodiment, the paper P is conveyed with the end portion (first end E1) on the first width direction W1 side aligned, and the reference line KS matches the center line of the A5 paper A5R. Is set to In FIG. 10, the A3 center line TS3 indicates the center line of the A3 sheet A3, and the A4 center line TS4 indicates the center line of the A4 sheet A4R. Note that the center line of the horizontal A4 paper A4 coincides with the A3 center line TS3, and is therefore omitted. The distance from the reference line KS to the A3 center line TS3 (A3 center line distance TW3) is about 74 mm, and the distance from the reference line KS to the A4 center line TS4 (A4 center line distance TW4) is about 31 mm. . As described above, if the configuration is such that the edges are aligned and transported, the paper P can be positioned with reference to the edges, and the transport accuracy of the paper P can be improved.

  The plurality of levers 20 are arranged in the same manner as in the second embodiment, and the first lever 20a and the third lever 20c provided on the first end E1 side have a distance from the reference line KS of the first lever width LW1. In the second lever 20b and the fourth lever 20d provided on the second end E2 side, the distance from the reference line KS is the second lever width LW2. That is, the plurality of levers 20 have different distances from the reference line KS on the first end E1 side and the second end E2 side. Note that the position of the lever 20 is not limited to this, and the position can be appropriately set in consideration of the paper P conveyed by the paper conveyance device.

  The sheet transport device further includes an auxiliary lever 27 having the same structure as the lever 20. For example, the auxiliary lever 27 is provided on the second end E2 side at a position that coincides with the first lever 20a and the third lever 20c in the transport direction H. The distance from the reference line KS to the auxiliary lever 27 (auxiliary lever width HW) is set larger than the second lever width LW2. That is, the auxiliary lever 27 is provided at a position farther from the reference line KS in the second width direction W2 than the second lever 20b and the fourth lever 20d.

  As described above, the plurality of levers 20 are alternately arranged with respect to the A5 paper A5R and the A4 paper A4R across the center line of the paper P, but the A3 paper A3 and the horizontal A4 paper A4 are arranged. Is arranged on the first end E1 side (left side in FIG. 10) from the center line (A3 center line TS3). However, by providing the auxiliary lever 27 disposed on the second end E2 side (right side in FIG. 10) from the A3 center line TS3, the load applied to the paper P can be adjusted so as not to be biased to one side.

  The above-described configuration is an example, and the position and number of the auxiliary levers 27 can be set as appropriate.

  It should be noted that the embodiment disclosed herein is illustrative in all respects and does not serve as a basis for limited interpretation. Therefore, the technical scope of the present invention is not interpreted only by the above-described embodiment, but is defined based on the description of the scope of claims. Moreover, all the changes within the meaning and range equivalent to a claim are included.

DESCRIPTION OF SYMBOLS 13 Registration roller 20 Lever 21 Lever oscillating part 21a Oscillating contact part 22 Lever support shaft 23 Detected part 24 Energizing fixing part 25 Energizing member 26 Paper detection sensor 30 Roller 51 First conveyance guide 51a Inner side surface 51b Outer side surface 51c Lever hole 51d Roller hole 100 Image forming apparatus 111, 121 Paper transport device E1 First end E2 Second end H Transport direction KS Reference line P Paper S Paper transport path W1 First width direction W2 Second width direction

Claims (7)

A paper transport device having a paper transport path for transporting paper,
The paper conveyance path is provided with a plurality of levers that come into contact with the leading edge of the conveyed paper,
In the width direction of the paper, when one side is the first side and the other side is the second side with respect to the center line of the paper ,
The plurality of levers are
They along the sheet conveying direction, are arranged alternately in the first side and the second side,
The distance from the center line differs between the first side lever arranged on the first side and the second side lever arranged on the second side,
The sheet conveying apparatus according to claim 1, wherein the first side lever and the second side lever have different lever loads, which are loads on the contacted sheet. The sheet conveying device according to claim 1,
The first side lever is disposed at a position where the distance from the center line is shorter than the second side lever,
The lever load at the first side lever is set larger than the lever load at the second side lever.
A paper conveying device characterized by the above. The sheet conveying device according to claim 1 or 2,
The first side lever and the second side lever are arranged so that the product of the distance from the center line and the lever load is substantially equal.
A paper conveying device characterized by the above. It is a paper conveying apparatus as described in any one of Claim 1- Claim 3 , Comprising:
Provided in the paper transport path, comprising a registration roller for receiving the leading edge of the paper,
The plurality of levers are provided with the same number of levers on the first side and the second side between the upstream side in the transport direction and the registration roller. A sheet conveying apparatus according to any one of claims 1 to 4 , wherein
A paper conveying apparatus comprising: a paper detection sensor that detects the position of the paper based on the plurality of levers contacting the paper. It is a paper conveying apparatus as described in any one of Claim 1- Claim 5 , Comprising:
A roller provided in the paper transport path for transporting paper;
Among the plurality of levers, levers adjacent in the transport direction are provided so as to sandwich the roller in the transport direction. An image forming apparatus having a sheet conveying device according to any one of claims 1 to 6.

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