JP2008127161A - Sheet processing device and image forming device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent clogging of a carrying passage when a side end of a sheet contacts with a pressing member when carrying the wide sheet to a sheet processing device. <P>SOLUTION: The sheet S ejected from an image forming device is aligned being carried to the sheet processing device. The sheet processing device has a processing tray, an offset roller 407 and a sheet pressing member 700. The wide sheet S is carried on the processing tray while passing through a recess part 701 formed in the sheet pressing member 700. The side end of the sheet S carried on the processing tray is separated from the recess part 701 by the offset roller 407 moving in the width direction, and the sheet S having the side end separated from the recess part 701 is aligned by rotation and the movement of the offset roller 407. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a sheet processing apparatus capable of aligning sheets while preventing interference with a pressing member that presses the sheet, and an image forming apparatus including the sheet processing apparatus.

  Conventionally, some image forming apparatuses that form an image on a sheet include a sheet processing apparatus that processes a sheet discharged from the image forming apparatus. The sheet processing apparatus aligns the sheet by aligning the rear end of the discharged sheet in the sheet conveying direction and the side end along the direction intersecting the sheet conveying direction, and performs processing such as punching and stapling on the aligned sheet. Can be bundled into a predetermined sheet bundle (see Patent Document 1).

  The sheet processing apparatus described in Patent Document 1 receives a sheet discharged from the image forming apparatus main body at a sheet receiving unit provided in the sheet processing apparatus. The sheet received by the sheet receiving unit passes through the transport path, and is transported toward the processing tray by driving of the transport roller detected by the entrance sensor.

  When the sheet conveyed to the processing tray is detected by a sheet bundle discharge sensor provided on the processing tray, the sheet is conveyed toward the downstream side in the conveying direction by the rotation of the offset roller. The sheet conveyed toward the downstream side in the conveyance direction is conveyed toward the upstream side in the conveyance direction by an offset roller that reverses when a predetermined time has elapsed. As described above, the trailing edge of the sheet conveyed toward the upstream side in the conveyance direction is abutted against and aligned with the sheet trailing edge stopper standing at the upstream end of the processing tray in the conveyance direction. .

  The sheet with the trailing edge aligned is positioned between the pressing member and the processing tray by the movement of the offset roller in the direction (width direction) intersecting the sheet conveyance direction, and the side edge standing on the side edge of the processing tray. Abutting against the positioning wall, the side edges in the width direction of the sheet are aligned.

JP 2005-132611 A

  However, when a sheet other than the prescribed size, for example, a wide sheet of A3 size or larger, is discharged from the image forming apparatus main body, the side edge of the sheet comes into contact with the pressing member and clogs the conveyance path. There is a case. Further, even if the sheet is conveyed to the processing tray without clogging the conveying path, if the side edge of the sheet comes into contact with the pressing member, the sheet is stacked in a skewed state on the processing tray. May not be consistent depending on the operation.

  For this reason, in consideration of the case where a wide sheet is discharged, it is conceivable that the pressing member is arranged close to the side end positioning wall so as not to contact the sheet. However, when the pressing member is arranged close to the side end positioning wall, only the vicinity of the side edge of the sheet is pressed by the pressing member, and thus the aligned sheet may be displaced. Further, if the arrangement of the pressing member is changed, it is conceivable that the configuration of the apparatus becomes complicated, for example, the amount of operation of the offset roller increases, and the lateral width of the sheet processing apparatus increases to increase the cost of the product.

  Therefore, the present invention forms an escape portion in the pressing member, and when a wide sheet is discharged, the side edge of the sheet passes through the escape portion to avoid interference between the sheet and the pressing member, Accordingly, an object of the present invention is to provide a sheet processing apparatus that solves the above problems.

The sheet processing apparatus of the present invention includes a sheet stacking unit on which the conveyed sheets are stacked,
Sheet moving means for moving the sheets stacked on the sheet stacking means in a direction crossing the sheet conveying direction;
A side end alignment member for receiving a side end of the sheet moved by the sheet moving means;
In a sheet processing apparatus comprising: a pressing member that is movable up and down to press the sheet received by the side edge alignment member against the sheet stacking unit;
The pressing member has an escape portion that avoids interference with a side edge of the conveyed sheet,
The sheet moving means moves the sheet to the side edge aligning member after removing the sheet loaded on the sheet stacking means and having a side edge engaged with the relief part from the escape part. It is characterized by that.

The image forming apparatus of the present invention includes an image forming unit that forms an image on a sheet,
A sheet processing apparatus configured to process a sheet on which an image is formed by the image forming unit.

  In this sheet processing apparatus, when a wide sheet is conveyed toward the sheet stacking unit by the sheet conveying unit, the side end of the sheet passes through the escape portion, so that the sheet is conveyed by interference between the side end of the sheet and the pressing member. It is possible to prevent the passage from being clogged. Further, it is possible to prevent the side edge of the sheet and the pressing member from interfering with each other and skewing and discharging the sheet to the sheet stacking unit.

  In addition, since the image forming apparatus includes the sheet processing apparatus, it is possible to prevent the apparatus from becoming large and to suppress an increase in product cost.

  Hereinafter, an image forming apparatus for forming an image on a sheet and the sheet processing apparatus of the present invention will be described with reference to the drawings.

  FIG. 1 is a cross-sectional view of a copying machine showing an example of an image forming apparatus provided with a sheet processing apparatus. For example, the image forming apparatus A as an image forming unit includes an image forming apparatus main body 500 that forms an image, an automatic document feeder (ADF) 300 provided on the upper surface of the image forming apparatus main body 500, and the image forming apparatus A. A sheet processing apparatus 400 that processes the discharged sheets.

  A reader unit 120 is disposed above the image forming apparatus main body 500, and a document image sent from the automatic document feeder 300 is read by the reader unit 120. The upper part of the reader unit 120 is covered with a glass plate 102, and the document conveyed to the glass plate 102 is irradiated by a lamp 103 of the scanner 104 unit that moves on the lower surface side of the glass plate 102. The document irradiated by the lamp 103 is read by the CCD image sensor unit 109 through the mirrors 105, 106, 107 and the lens 108, and the read image is digitally processed by photoelectric conversion or the like.

  The digitally processed image signal is converted into an optical signal modulated by the exposure control unit 201 of the printer unit 200 arranged in the middle stage of the image forming apparatus main body 500, and is irradiated toward the photosensitive drum 202. The photosensitive drum 202 irradiated with the modulated light has a latent image formed on the irradiated portion and is developed into a toner image by the toner supplied from the developing unit 203.

  The toner image is transferred to the sheet cassette 204 or the sheet S conveyed from the sheet cassette 205 by the transfer unit 206, and the sheet S to which the toner image has been transferred is heated and pressed by the fixing unit 207 to be fixed. Thereafter, the sheet S is discharged toward the sheet processing apparatus 400 from a paper discharge unit 208 disposed at the top of the image forming apparatus main body 500.

  The sheet S on which an image has been formed and discharged to the sheet processing apparatus 400 is sorted according to an operation mode designated in advance by the sheet processing apparatus 400, or processing such as punching or binding is performed.

  The sheet processing apparatus 400 according to the present embodiment has a stapling function for binding the end portions of the sheets S stacked at a certain thickness in addition to the sorting function for sorting the sheets S discharged from the paper discharge unit 208.

  As shown in FIGS. 2 and 3, the sheet processing apparatus 400 includes, for example, a processing tray 410 that is a sheet stacking unit that stacks and processes the sheets S sequentially discharged from the image forming apparatus main body 500. Further, the sheet processing apparatus 400 includes a stack tray 421 that finally accumulates a bundle of sheets processed on the processing tray 410. The sheet processing apparatus 400 generates a sheet bundle corresponding to the number of sheets on the processing tray 410 and discharges the sheet bundle to the stack tray 421 for each sheet bundle.

  The processing tray 410 includes a conveyance path 450 through which the sheet S discharged from the image forming apparatus main body 500 passes, a conveyance roller 405 that conveys the sheet S on the conveyance path 450, and an offset roller 407 that aligns the conveyed sheet S. And have. Further, the processing tray 410 has a sheet pressing member 700 (FIGS. 4 and 6) that presses the sheet S conveyed to the processing tray 410.

  At the front end of the conveyance path 450, a sheet receiving unit 401 disposed near the paper discharge unit 208 is formed, and receives the sheet S discharged from the image forming apparatus main body 500, and is located behind the conveyance path 450. Leading towards. In this case, the sheet S received by the sheet receiving unit 401 is detected by the entrance sensor 403 installed in the transport path 450 and then transported toward the processing tray 410 by the transport roller 405.

  As shown in FIGS. 4 and 5, the conveyance roller 405 and the offset roller 407 are rotated via belts 431 a, 431 b, and 431 c by the rotation of the conveyance motor 431. The transport roller 405 and the offset roller 407 are rotated in the transport direction or in the reverse direction of the transport direction (hereinafter referred to as reverse rotation) by an amount corresponding to the rotation amount of the transport motor 431 in response to the drive of the transport motor 431.

  In this case, for example, an offset roller 407 serving as a sheet moving unit is attached to the shaft 406a via an offset roller arm 406 supported so as to be movable in the axial direction of the shaft 406a. The offset roller arm 406 is movable in the width direction via the pinion 423 and the rack 424 by driving of the offset motor 432, and can be raised and lowered by the pickup solenoid 433 with the shaft 406a as a fulcrum.

  In other words, when the sheet S is discharged toward the processing tray 410, the offset roller 407 is moved upward by the offset roller arm 406 that moves up and down by the on / off operation of the pickup solenoid 433. By moving the offset roller 407 upward, the sheet S can be conveyed from the conveyance path 450 toward the processing tray 410.

  A side end positioning wall 416 that can come into contact with the side end of the sheet S conveyed to the processing tray 410 is provided on the side of the processing tray 410 in parallel with the conveyance direction of the sheet S. In this case, the side end positioning wall 416 constitutes a side end alignment member, and serves as an alignment position reference for aligning the side ends of the sheet S in the direction intersecting the sheet conveying direction (hereinafter referred to as the width direction). . In addition, a stapler unit 420 that performs a stapling process on a sheet bundle aligned on the processing tray 410 is disposed in front of the side end positioning wall 416.

  As shown in FIGS. 6, 7, and 8, the sheet pressing member 700 is rotatably supported by the shaft 406 a, and presses the sheet S conveyed to the processing tray 410 by the weight of the sheet pressing member 700. Yes. In this case, the sheet pressing member 700 forms a pressing member for pressing the sheet S.

  The sheet pressing member 700 includes a pressing surface 700b that contacts the sheet surface and presses the sheet S, and a floating piece 700c formed with a slope 700a that receives the lower surface of the offset roller arm 406 (see FIG. 9). Further, an escape portion 701 is formed in the middle portion in the vertical direction of the sheet pressing member 700, which is notched in a concave shape in the conveyance direction of the sheet S.

  The escape portion 701 can pass the side edge of the sheet S when the wide sheet S is conveyed to the processing tray 410, and the side end of the sheet S passes the escape portion 701, thereby allowing the sheet S and the sheet presser to pass. Interference with the member 700 is avoided. In this case, the relief portion 701 can be formed by a groove formed in the intermediate portion in the vertical direction of the sheet pressing member 700 in the direction in which the sheet S is conveyed. Alternatively, the escape portion 701 can be formed by cutting a portion of the sheet pressing member 700 where the sheet S is conveyed and forming the cross-sectional shape of the sheet pressing member 700 in an L shape.

  Next, the operation of the sheet processing apparatus 400 having the above configuration will be described.

  The sheet S on which an image has been formed by the image forming apparatus main body 500 is received by the sheet receiving unit 401 of the sheet processing apparatus 400, and is transported toward the processing tray 410 through the transport path 450 by the rotation of the transport roller 405. Of the sheets S conveyed through the conveyance path 450, the wide sheet S is conveyed toward the processing tray 410 while the side edge of the sheet passes through the escape portion 701 formed in the sheet pressing member 700 (see FIG. 6). ).

  Next, when the entrance sensor 403 detects that the trailing edge of the sheet S has moved away from the nip of the conveying roller 405, the rotation of the conveying roller 405 and the offset roller 407 is temporarily stopped. Next, the offset roller 407 (FIG. 6) that has been waiting in advance is lowered by turning off the pickup solenoid 433 (FIG. 7). The lowered offset roller 407 abuts on the sheet S in a state straddling the conveyance path 450 and the processing tray 410, moves in a direction away from the side end positioning wall 416 (in the direction of arrow H in FIG. 7), The side edge of the sheet S in the escape portion 701 is separated from the escape portion 701.

  The offset roller 407 rotates in the sheet conveying direction for a predetermined time and moves the sheet S detached from the escape portion 701 in the sheet conveying direction (FIG. 8A), and then reverses when a predetermined time elapses. The sheet S is moved in the direction opposite to the sheet conveying direction (FIG. 8B).

  When the sheet S moves in the direction opposite to the sheet conveying direction, the sheet clamp member 412 that holds the sheets stacked on the processing tray 410 moves to a position where the sheet S is raised to receive the sheet S. .

  The rear end of the sheet S moved by the reverse rotation of the offset roller 407 is abutted against a sheet rear end stopper 411 provided upright at the upstream end of the processing tray 410 in the conveyance direction. The rotation of the offset roller 407 stops, and the conveyance direction of the sheet S (the rear end of the sheet S) is aligned.

  Next, the offset roller 407 moves in the direction approaching the side end positioning wall 416 (the direction of the arrow K in FIG. 8C), and moves the sheet S whose rear end is aligned in the width direction. As shown in FIG. 9, the sheet S moving in the width direction enters between the pressing surface 700 b and the processing tray 410 while being guided by the guide surface 700 d of the sheet pressing member 700, and is abutted against the side end positioning wall 416. The side edges are aligned. In this case, the guide surface 700d is an inclined surface inclined in a direction toward the side end positioning wall 416.

  In this case, the offset roller 407 moves the sheet S in a state where the side edge Sa of the sheet S is guided by the escape portion 701 in the sheet conveying direction and aligns the sheet S in the conveying direction. The side edge Sa of the sheet S may be moved away from the escape portion 701 by moving in a direction away from the end positioning wall 416.

  In consideration of a case where the sheet S is skewed and discharged from the image forming apparatus main body 500, the offset roller 407 further contacts the sheet S with the side end positioning wall 416, and then further moves the sheet S to the side by about 5 mm. It moves toward the end positioning wall 416. When the offset roller 407 transports the sheet S excessively, a loop D is formed at the side end portion of the sheet S that is in contact with the side end positioning wall 416, and the sheet pressing member 700 is pushed up by the formed loop D.

  When the offset roller 407 moves in a direction approaching the side end positioning wall 416, the offset roller arm 406 rides on the inclined surface 700a of the sheet pressing member 700 and floats upward (in the direction of arrow F) due to the inclination of the inclined surface 700a. The offset roller 407 is separated from the upper surface of the sheet S by a distance E as the offset roller arm 406 is lifted.

  At this time, the sheet pressing member 700 pushed up by the loop D can add the weight of the offset roller arm 406 and the offset roller 407 to the weight of the sheet pressing member 700 and increase the force for pressing the sheet S.

  As described above, when the offset roller 407 moves away from the sheet surface while the side edge of the sheet S is pressed by the sheet pressing member 700, the part other than the side edge of the sheet S moves in the arrow H direction and is formed on the sheet. Loop D that has been released is released. As a result, the sheet S is aligned in a state where the side end is in contact with the side end positioning wall 416.

  Next, as an example in which sheets with different widths are conveyed, a so-called center reference in which the width center of the sheet S coincides with the width center of the conveyance path 450 and is sent to the sheet processing apparatus 400 will be described.

  Here, the distance from the position where the offset roller 407 stands by until the offset roller arm 406 rides on the slope 700a is constant regardless of the width size of the sheet. For this reason, if the offset roller 407 is made to stand by at the center of the width of the sheet and alignment in the width direction of the sheet is performed, the following problems occur. That is, the side edge of the sheet S is closer to the side edge positioning wall 416 as the width of the sheet S is wider. For example, as shown in FIG. 10, a wide sheet has a short distance Y from the side end of the sheet S to the side end positioning wall 416, so that it comes into contact with the side end positioning wall 416 quickly and a large loop D is formed. The sheet S may be buckled and cannot be aligned.

  In the present embodiment, when the sheet S having a different width depending on the center reference is conveyed to the processing tray 410, the offset roller 407 starts from the side edge Sa of each sheet regardless of the sheet width, as shown in FIG. It waits at a position X separated by a certain distance. In this case, the position X is a position where the offset roller 407 contacts the sheet S.

  Each sheet S conveyed according to the center reference differs in the distance Y from the side end Sa to the side end positioning wall 416 depending on the sheet width, but the size of the loop D is substantially the same regardless of the width size of the sheet S. Formed. That is, since the amount of movement from when the side end Sa contacts the side end positioning wall 416 to when the offset roller 407 moves away from the sheet by the inclined surface 700a is the same, the size of each loop D is the same. As a result, the sheet processing apparatus 400 can stably and accurately align the side edge Sa regardless of the width of the sheet S.

  The position X is preferably set larger as the width of the sheet S is wider. That is, when the width of the sheet S is wide, the contact area between the sheet S and the processing tray 410 is increased and the sliding resistance of the sheet S is increased. Therefore, when the sheet S is moved in the width direction, the offset roller 407 is moved. There are cases where the sheet S slips from the S surface and the sheet S cannot be moved accurately. For this reason, if the amount by which the offset roller 407 slides with respect to the sheet S is expected and the value of the position X is set to be large according to the width of the sheet S, the alignment accuracy of the sheet S can be improved.

  Next, a so-called one-side reference in which the side edge Sa of the sheet S is conveyed to a position that is always spaced from the one side of the conveyance path 450 by a certain distance will be described.

  As shown in FIG. 11, the sheet S conveyed by the one-side reference has the same distance Y from the side end Sa of the sheet S to the side end positioning wall 416 regardless of the sheet width. For this reason, the offset roller 407 has only to stand by at the position X at the same distance from the side edge Sa of the sheet S regardless of the sheet width. That is, the offset roller 407 in the case of the one-side reference stands by at a position where the distance Y from the side end Sa to the position X is added to the distance Y from the side end positioning wall 416 to the side end Sa. When the sheets S are aligned based on the one-side reference, the offset roller 407 needs to move by a certain distance.

  As described above, a wide sheet S (a sheet other than the specified size, for example, a wide sheet of A3 size or larger) among the sheets conveyed by the center reference or the one-side reference is shown in FIG. As shown, the left side end Sa in FIG. 6 is conveyed to the processing tray 410 while passing through the escape portion 701 provided in the sheet pressing member 700. Then, as shown in FIG. 7, the offset roller 407 moves a predetermined distance in the direction H away from the side end positioning wall side 416 along the shaft 406 a while being in contact with the sheet S, and moves to the side from the escape portion 701. The end Sa is released. Next, as shown in FIG. 8A, the sheet S is conveyed to the processing tray 410 by a predetermined distance by the normal rotation of the offset roller 407. Next, as shown in FIG. 8B, the sheet S conveyed to the processing tray 410 is abutted against the sheet trailing edge stopper 411 by the reversely rotating offset roller 407 to convey the sheet. The direction is aligned.

  Then, as shown in FIGS. 8C and 9, the side edge Sa of the sheet S detached from the escape portion 701 is pressed by the offset roller 407 that moves in the direction K close to the side edge positioning wall side 416. While being guided by the guide surface 700 d of the member 700, it enters between the pressing surface 700 b and the processing tray 410. The side end Sa of the sheet S entering between the pressing surface 700b and the processing tray 410 moves until it abuts against the side end positioning wall 416, and the width direction of the sheet S is aligned.

  In this case, since the vertical dimension of the escape portion 701 is set larger than the vertical dimension of the conveyance path 450, the sheet S is not returned to the conveyance path 450 by the reverse rotation of the offset roller 407. . Further, the offset roller 407 is moved in the direction H to release the side edge Sa from the escape portion 701, and the offset roller 407 reverses after conveying the sheet S by a predetermined distance, and the sheet trailing edge is set to the sheet trailing edge stopper 411. It is also possible to replace the operation that hits the.

  When the operation of the offset roller 407 is completed, the sheet clamp member 412 attached to the sheet trailing edge stopper 411 presses the trailing edge of the sheet S toward the processing tray 410. The sheet pressed against the processing tray 410 by the sheet clamp member 412 is held in an aligned state without being affected by the accompanying conveyance by the sequentially conveyed sheets.

  When the offset roller 407 starts to reverse, the sheet clamp member 412 stands by at a position rotated upward so that the rear end of the sheet S can be received (see FIG. 8B). Similarly, when the sheet S is moved in the direction K close to the side end positioning wall side 416 by the offset roller 407, the sheet clamp member 412 stands by at a position rotated upward.

  The sheet S with the rear end and the side end Sa aligned is stapled by the stapler unit 420 or remains aligned and is discharged from the processing tray 410 toward the stack tray 421 by the operation of the sheet bundle discharging member 413. The As illustrated in FIG. 12, the sheet bundle discharge member 413 discharges the sheet bundle toward the stack tray 421 while the sheet bundle is held by the sheet clamp member 412.

  When the trailing end of the sheet bundle discharged by the sheet bundle discharge member 413 reaches the end of the processing tray 410, the sheet bundle is not held by the sheet clamp member 412, and the sheet bundle is discharged to the stack tray 421.

  As described above, in the sheet processing apparatus 400, since the side edge of the wide sheet passes through the escape portion 701 formed in the sheet pressing member 700, the sheet is directed toward the processing tray 410 without interfering with the sheet pressing member 700. Can be transported.

  As described above, since the escape portion 701 is provided in the sheet pressing member 700, even a wide sheet S can be aligned without being obstructed by the sheet pressing member 700. Further, by providing the escape portion 701, it is possible to handle a wide sheet S without increasing the size of the sheet processing apparatus 400, so that it is possible to prevent the image processing apparatus from being enlarged and to suppress an increase in product price. it can.

1 is a cross-sectional view of an image forming apparatus including a sheet processing apparatus according to an embodiment of the present invention. It is sectional drawing which shows the structure of a sheet processing apparatus. It is a figure which expands and shows the processing tray part of a sheet processing apparatus. FIG. 4 is a view illustrating the periphery of a conveyance roller and an offset roller of a sheet processing apparatus. FIG. 4 is a view illustrating the periphery of a conveyance roller and an offset roller of a sheet processing apparatus. It is a figure which shows the state of the offset roller before a sheet | seat is conveyed to the process tray of a sheet processing apparatus. It is a figure which shows the state of the offset roller after a sheet | seat is conveyed by the processing tray of a sheet processing apparatus. It is a figure which shows a mode that an offset roller moves the sheet conveyed to the processing tray of the sheet processing apparatus. It is a figure which shows a mode that the sheet conveyed to the processing tray of a sheet processing apparatus aligns with an offset roller. FIG. 6 is a diagram illustrating a positional relationship between a sheet conveyed by a center reference and an offset roller. It is a figure which shows the positional relationship of the sheet | seat conveyed by the one-side reference | standard, and an offset roller. It is a figure which shows the sheet | seat bundle discharge member which discharges | emits the sheet | seat bundle which completed the process toward a stack tray.

Explanation of symbols

A Image forming apparatus (image forming means)
S sheet Sa side edge 400 sheet processing device 407 offset roller (sheet moving means)
410 processing tray (sheet stacking means)
416 Side end positioning wall (side end alignment member)
700 Sheet pressing member (pressing member)
701 Escape part

Claims (4)

A sheet stacking means on which the conveyed sheets are stacked;
Sheet moving means for moving the sheets stacked on the sheet stacking means in a direction crossing the sheet conveying direction;
A side end alignment member for receiving a side end of the sheet moved by the sheet moving means;
In a sheet processing apparatus comprising: a pressing member that is movable up and down to press the sheet received by the side edge alignment member against the sheet stacking unit;
The pressing member has an escape portion that avoids interference with a side edge of the conveyed sheet,
The sheet moving means moves the sheet to the side edge aligning member after removing the sheet loaded on the sheet stacking means and having a side edge engaged with the relief part from the escape part. Let
A sheet processing apparatus. The escape portion is a groove formed along the sheet conveying direction in an intermediate portion in the vertical direction of the pressing member.
The sheet processing apparatus according to claim 1. The pressing member is a member having an L-shaped cross section in which the escape portion is formed by cutting away a portion facing the upper sheet moving means from an intermediate portion in the vertical direction.
The sheet processing apparatus according to claim 1. An image forming means for forming an image on a sheet;
A sheet processing apparatus for processing a sheet on which an image is formed by the image forming unit,
The sheet processing apparatus is the sheet processing apparatus according to any one of claims 1 to 3.
An image forming apparatus.

Images