JP4518897B2 - Sheet processing apparatus and image forming apparatus having the same - Google Patents

Description

  The present invention relates to a sheet processing apparatus for aligning end portions of sheets, and in particular, to a sheet processing apparatus capable of aligning even if the end portions of the sheet are curled, and image formation including the sheet processing apparatus in the apparatus main body. Relating to the device.

  2. Description of the Related Art Conventionally, a sheet processing apparatus that performs processing on a sheet is installed on the side of an apparatus main body of an image forming apparatus, and conveys a sheet discharged from the apparatus main body of the image forming apparatus to a sheet processing unit. In some cases, processing such as sheet stacking alignment operation for stacking and aligning discharged sheets and stapling operation for binding sheets is performed. Examples of the image forming apparatus include a copying machine, a printer, a facsimile, and a composite device thereof.

  In such a conventional sheet processing apparatus, when processing a bundle of sheets, the sheet is discharged from the discharge passage so as to fly onto the processing tray, and the sheet is transported in the sheet conveying direction of the side edge along the sheet conveying direction. On the other hand, the sheet bundle is bound after aligning the ends along the intersecting direction (see Patent Document 1).

  The sheet processing apparatus for aligning sheets as described above includes, for example, an alignment member that rotates in synchronization with an elastic member 671 called a paddle and a discharge roller 617 that discharges the sheet S onto the processing tray 672 as shown in FIG. 619 is pulled back to the nip point between the alignment belt 619 and the processing tray 672 by the elastic member 671 and then the sheet S is not shown by the frictional force of the alignment belt 619. The rear end is aligned by abutting against the alignment abutting member. And the conventional sheet processing apparatus, in order to improve the consistency of the sheet where the end portion along the direction intersecting the sheet conveying direction of the sheet is curled downward (lower front and rear curl), A sheet pressing member (not shown) that presses the sheet from above is provided in the vicinity of the alignment butting member to prevent alignment failure due to buckling or the like during alignment.

JP 2002-37512 A

  However, the conventional sheet processing apparatus uses the frictional force obtained by the rotation of the elastic member 671 as a means for aligning the sheet S to discharge the sheet S on the processing tray 672 so as to align the sheet S. Since the sheet is aligned while pressing the sheet, it is difficult to set the frictional force of the elastic member 671, the pressing force of the sheet pressing member (not shown), and the configuration is complicated.

  Further, the conventional sheet processing apparatus has a problem that sheet width alignment cannot be reliably performed because the side end portion along the sheet conveyance direction is not pressed.

  An object of the present invention is to provide a sheet processing apparatus capable of stably aligning curled sheets with a simple configuration.

  An object of the present invention is to provide an image forming apparatus having a sheet processing apparatus capable of stably aligning curled sheets and having improved image forming efficiency.

In order to achieve the above object, a sheet processing apparatus according to the present invention is configured to contact a sheet stacking unit on which a sheet transported in a predetermined transport direction is stacked, the sheet fed to the sheet stacking unit, and A sheet conveying unit capable of conveying in an upstream direction opposite to the conveying direction and a direction intersecting the conveying direction; and provided upstream of the sheet stacking unit in the conveying direction. An upstream end aligning unit that aligns the sheet by abutting the upstream end of the sheet conveyed to the upstream side in the conveying direction, and the sheet conveyed in the direction intersecting the conveying direction by the sheet conveying unit. a side edge aligning means for performing alignment of the sheet abutted against the side edge along the conveying direction, provided on the upstream side in the transport direction of the sheet stacking means, and is conveyed for alignment And notches upstream end of the over bets enters, provided in the sheet upstream side in the conveying direction of and the sheet stacking means in the vicinity of the side edge aligning means, upstream of the sheet upstream end enters into the notch comprising a staple processing section that performs staple processing on the end portion,
The sheet conveying means conveys a plurality of sheets fed to the sheet stacking means one by one to the upstream side in the conveying direction, and causes the upstream end of the sheet to enter the notch, After abutting the upstream end against the upstream end aligning means, the sheet is transported in a direction intersecting the transport direction, and the side edge of the sheet along the transport direction is thrust against the side end aligning means. A sheet bundle is formed on the sheet stacking means by applying and aligning the sheets, and the staple processing unit performs a stapling process on an upstream end portion of the sheet bundle aligned on the sheet stacking means. It is characterized by.

In order to achieve the above object, an image forming apparatus according to the present invention includes: an image forming unit that forms an image on a sheet; and a sheet processing device that processes a sheet on which an image is formed by the image forming unit. The processing apparatus is the sheet processing apparatus described above .

  In the sheet processing apparatus of the present invention, the upstream end receiving portion for receiving the upstream end portion of the sheet is provided on the upstream side of the sheet stacking means. Therefore, the aligned preceding sheet is not pushed by the succeeding sheet to be aligned next, and the sheet with the rear end curled downward can be stably aligned with a simple configuration.

  In the sheet processing apparatus according to the present invention, the upstream end receiving portion for receiving the upstream end portion of the sheet is provided in the vicinity of the upstream end receiving portion of the sheet stacking means, so that the sheet whose rear end portion is curled downward is aligned. At this time, the aligned preceding sheet is not pushed by the succeeding sheet to be aligned next, and the sheet with the rear end curled downward can be stably aligned with a simple configuration.

  In the sheet processing apparatus of the present invention, since the side end receiving portion for receiving the side end portion of the sheet is provided in the vicinity of the side end receiving portion of the sheet stacking means, the sheets whose side end portions are curled downward are aligned. At this time, the aligned preceding sheet is not pushed by the succeeding sheet to be aligned next, and the sheet with the side end curled downward can be stably aligned with a simple configuration.

  In the image forming apparatus of the present invention, since the end portions of the sheets are stably aligned, the sheets can be smoothly discharged to the sheet processing apparatus, and the image forming efficiency of the sheets can be improved.

  Hereinafter, a sheet processing apparatus according to an embodiment of the present invention and an image forming apparatus including the sheet processing apparatus in an apparatus main body, for example, a copying machine will be described with reference to the drawings.

  FIG. 1 is a front view of a schematic configuration of a copier equipped with a sheet processing apparatus of the present invention in an apparatus main body.

  Examples of the image forming apparatus include a copying machine, a facsimile, a printer, and a complex machine of these. Therefore, the image forming apparatus is not limited to a copying machine.

  Further, the sheet processing apparatus 400 of the present invention is not connected only to the apparatus main body 500A of the copying machine 500. The sheet processing apparatus 400 is separate from the apparatus main body 500A of the copier 500, but may be incorporated in the apparatus main body 500A.

  Further, the sheet processing apparatus of the present embodiment includes a stapler unit 420 (see FIG. 4) to bind the sheet bundle. However, instead of the stapler unit 420, a sheet punching apparatus is provided to punch holes in the sheet bundle. It may be like this. Therefore, the sheet processing apparatus is not limited to binding a sheet bundle. Furthermore, a stapler unit and a punching device are not necessarily required. The sheet processing apparatus may have at least a function of aligning the trailing edge of the sheet.

  In the present invention, the upstream end of the sheet in the sheet conveying direction is referred to as the rear end, the downstream end is referred to as the leading end, and the end along the sheet conveying direction is referred to as the side end. A direction intersecting the sheet conveyance direction is called a sheet width.

  The copying machine 500 includes a reader unit 120, a sheet image forming unit such as a printer unit 200, a sheet processing apparatus 400, and the like. An automatic document feeder 300 (hereinafter referred to as “ADF”) for supplying documents one by one onto the platen glass 102 is provided on the upper part of the apparatus main body 500A of the copying machine 500. A sheet processing apparatus 400 that performs post-processing of sheets discharged from the copying machine 500 is connected to the side of the apparatus main body 500A of the copying machine 500.

  The copying machine 500 reads an image of a document supplied by the ADF 300 with the reader unit 120 or reads an image of a document placed on the platen glass 102 of the reader unit 120 by the user with the reader unit 120. In addition to functioning as a copying machine for copying on a sheet by the unit 200, the printer unit 200 receives an image signal sent from an external personal computer and functions as a printer for forming the image signal on a sheet. Yes. Further, the copier 500 transmits an image signal read by the reader unit 120 to another facsimile, or receives a facsimile signal from another facsimile by the printer unit 200, and prints an image on a sheet based on the signal. It also functions as a facsimile machine to be formed.

  In FIG. 1, a reader unit 120 converts an image of a document into image data. The printer unit 200 has a plurality of types of sheet cassettes 204 and 205 on which a plurality of sheets are stacked, and outputs image data as a visible image on a sheet in accordance with a print command.

  When reading an original image and forming an image, the reader unit 120 first conveys originals stacked on the ADF 300 one by one onto the platen glass surface 102 one by one.

  Next, when the document is conveyed to a predetermined position on the glass surface 102 in this way, the lamp 103 of the reader unit 120 is turned on, and the scanner unit 104 moves to irradiate the document. Then, the reflected light from the original passes through the mirrors 105, 106, 107 and the lens 108 and is input to the CCD image sensor unit 109, where electric processing such as photoelectric conversion is performed in the CCD image sensor unit 109. Digital processing is applied.

  The image signal thus subjected to the electrical processing is converted into a modulated optical signal by the exposure control unit 201 of the printer unit 200 and irradiates the photosensitive drum 202. Then, a latent image is formed on the photosensitive drum 202 by the irradiation light, and the latent image is developed with toner by the developing unit 203. As a result, a toner image is formed on the photosensitive drum 202.

  Next, the sheet S is conveyed from the sheet cassettes 204 and 205 in synchronization with the leading edge of the toner image, and the toner image is transferred from the photosensitive drum 202 to the sheet S by the transfer unit 206. Thereafter, the toner image transferred to the sheet S is fixed by the fixing unit 207. The sheet S on which the toner image is fixed is discharged from the paper discharge unit 208 to the outside of the apparatus.

  Then, the sheet S discharged from the paper discharge unit 208 is conveyed to the sheet processing apparatus 400, and processing such as sorting and binding is performed according to the operation mode designated in advance by the sheet processing apparatus 400.

  Next, a case where images that are sequentially read are output (formed) on both sides of one sheet S will be described. First, the sheet S on which the toner image is fixed on one side by the fixing unit 207 is once subjected to the direction switching member 209. By being switched to the solid line direction in the figure, it is guided to the path 215, and further, the direction switching member 217 is transferred to the reverse path 212 via the path 218 by switching the direction switching member 213 to the broken line direction and the direction switching member 213 to the broken line direction. The

  Next, the sheet whose rear end has passed the direction switching member 213 is guided to the path 210 when the direction switching member 213 is switched to the solid line direction and the rotation direction of the roller 211 is reversed. It is conveyed to 206 and an image is formed on the back surface.

  The sheet processing apparatus 400 includes a stapling function that is a binding operation by the staple unit 420 in addition to a sorting operation for sorting sheets. As shown in FIG. 2, the sheet processing apparatus 400 includes, for example, a processing tray 410 that is a sheet stacking unit on which sheets S sequentially discharged from the apparatus main body 500 </ b> A of the copying machine are stacked, and sheets processed on the processing tray 410. A stack tray 421 and the like on which the bundle is finally stacked are provided, and a sheet bundle corresponding to the number of documents is formed on the processing tray 410 and discharged to the stack tray 421 for each sheet bundle.

  In the figure, a sheet receiving unit 401 is a part for receiving the sheet S discharged from the copying machine main body 500A. After the sheet S received by the sheet receiving unit 401 is detected by the entrance sensor 403, the sheet S is transported by a transport roller 405 and, for example, an offset roller 407, which is a sheet transport unit, and thereafter, as shown in FIG. 410 is discharged. The sheets S stacked on the processing tray 410 are detected by a sheet bundle discharge sensor 415 shown in FIG.

  The offset roller 407 is held by an offset roller arm 406 that can move up and down about a shaft 406 a shown in FIGS. 4 and 5 and can be moved up and down. When the sheet S is discharged to the processing tray 410, The offset roller arm 406 moves upward. As a result, the sheet S is discharged onto the processing tray 410 without being obstructed by the offset roller 407.

  The offset roller arm 406 is rotated in the vertical direction about a shaft 406a by a pickup solenoid 433. In other words, the offset roller 407 moves up and down by turning on and off the pickup solenoid 433.

  Further, as shown in FIG. 5, the offset roller 407 is rotated by belts 431a and 431b that are circulated by a conveyance motor 431 that drives the conveyance roller 405. When the transport motor 431 rotates, the offset roller 407 rotates (hereinafter referred to as reverse rotation) in the transport direction or in the reverse direction of the transport direction by an amount corresponding to the rotation amount of the transport motor 431.

  Note that the sheet processing apparatus 400 according to the present embodiment detects the sheet with the entrance sensor 403, conveys a predetermined amount of the sheet with the conveyance roller 405, and then turns off the pickup solenoid 433 and sets the offset roller 407 with its own weight. Then, the offset roller 407 is rotated in the sheet conveying direction for a predetermined time, and is further reversed when a predetermined time has passed.

  As described above, the offset roller 407 is rotated in the reverse direction so as to abut against, for example, the sheet rear end stopper 411 serving as the upstream end receiving means, thereby aligning the rear end of the sheet S. The sheet trailing edge stopper 411 is erected at the upstream end of the processing tray 410 in the sheet conveyance direction, and receives the upstream edge (rear edge) of the sheet.

  In FIG. 4, for example, a width direction positioning wall 416 that is a side end receiving means is a stopper that serves as an alignment position reference when aligning (width aligning) the side ends along the sheet conveying direction of the sheet. The stapler unit 420 is disposed in the vicinity of the width direction positioning wall 416 and binds the sheet bundle formed on the processing tray 410 (performs a stapling process). The offset roller 407 receives the driving force of the offset motor 432 via the pinion 435 and the rack 436, moves in the width direction (direction perpendicular to the sheet conveying direction), and approaches and separates from the width direction positioning wall 416. Can be done.

  When the offset roller 407 approaches the width direction positioning wall 416, the sheet abutted against the sheet rear end stopper 411 and aligned at the rear end moves to the width direction positioning wall 416 by the frictional force of the offset roller 407. Positioning and alignment in the width direction are performed. Note that after the sheet S hits the width direction positioning wall 416, the offset roller 407 moves slightly while sliding on the sheet and stops.

  By providing such an offset roller 407, the sheet discharged onto the processing tray 410 is once conveyed to the stack tray 421 side by the offset roller 407 that rotates in the sheet conveying direction as shown in FIG. 6A. Thereafter, as shown in FIG. 6B, the sheet is returned to the sheet trailing edge stopper 411 by the reverse rotation of the offset roller 407, and then the trailing edge is abutted against the trailing edge stopper 411 to align the trailing edge.

  In FIGS. 6 to 8, unlike FIG. 4, the offset roller 407 is described as having a configuration arranged inside the offset arm 406, but the difference in this configuration is merely in design. This is only a difference, and there is no difference in function and operation from that of the configuration shown in FIG.

  Thereafter, as shown in FIG. 6C, the offset roller 407 moves to the width direction positioning wall 416 side along the shaft 406a in a state where the offset roller 407 is in contact with the sheet S. The sheet S is pressed by the positioning wall 416, and the sheet S is aligned in the width direction.

  On the other hand, in FIG. 5, after the rear end of the sheet is aligned and the offset roller 407 is lifted by the pickup solenoid 433 as shown in FIG. 7A, the sheet clamp member 412 is aligned at the rear end. The sheet S is sandwiched between a pair of claws 412a and 412b by a biasing means (not shown) as shown in FIG. 7B. The upper claw 412a opens and closes with respect to the lower claw 412a. As a result, the sheet S previously discharged to the processing tray 410 is held at a predetermined position without being dragged downstream by the sheet S sequentially fed thereafter.

  The sheet clamp member 412 rotates upward as shown in FIG. 8A so that the sheet S can be received when the offset roller 407 is reversed, and the offset roller 407 is used to align the side edges of the sheet. At the same time, when the sheet S moves in the width direction, the sheet S is rotated upward as shown in FIG.

  In FIG. 5, the sheet bundle discharge member 413 discharges the processed sheet bundle to the stack tray 421. The sheet clamp member 412 is rotatably provided, and the aligned sheet bundle or the aligned and bound sheet bundle is processed as shown in FIG. 9 while being held by the sheet clamp member 412. It moves toward the stack tray 421 provided on the downstream side of the tray 410.

  When the sheet bundle discharge member 413 reaches the front end of the processing tray 410, which is the sheet discharge position indicated by the solid line in FIG. 9, the sheet bundle SA is released from being held by the sheet clamp member 412 on the stack tray 421. Is discharged to the stack tray 421.

  As described above, the sheet bundle discharge member 413 has a position for discharging the sheet to the stack tray 421 when the driving force of the sheet bundle discharge motor 430 is transmitted through the pinion 437 and the rack 438 as shown in FIG. It can be reciprocated between the home position near the rear end stopper 411. The sheet bundle discharge member 413 is normally fixed at the home position by excitation of the sheet bundle discharge motor 430.

  In FIG. 5, a clamp solenoid 434 is a solenoid that rotates the sheet clamp member 412. The clamp solenoid 434 moves integrally with the sheet bundle discharge member 413, and when the offset roller 407 once conveys the sheet to the downstream side, stops rotating, and moves in the width direction, and the sheet bundle discharge member 413. When the sheet reaches the position for discharging the sheet (the position indicated by the solid line in FIG. 9), the sheet clamp member 412 is turned on via the lever 434a.

  In the sheet processing apparatus 400 of the present embodiment, after the sheet S is moved in the width direction, the offset roller 407 is reversed again to complete the alignment operation in order to correct the deviation in the sheet conveyance direction. As a result, high-precision matching is realized. When the alignment process for the designated number of sheets is completed, the clamp solenoid 434 closes the sheet clamp member 412 and holds the sheet bundle.

  FIG. 10 is a block diagram illustrating a configuration of a control unit of the sheet processing apparatus 400. The CPU 100 has a ROM 110 therein, and the ROM 110 stores programs corresponding to control procedures shown in FIGS. 13 and 14 described later. The CPU 100 controls each unit while reading this program.

  The CPU 100 has a built-in RAM 120 in which work data and input data are stored. The CPU 100 controls each unit based on data stored in the RAM 120. Furthermore, sensors such as an inlet sensor 403 and a sheet bundle discharge sensor 415 are connected to the input port of the CPU 100. Further, motors and solenoids such as a conveyance motor 431, an offset motor 432, a sheet bundle discharge motor 430, a stack tray lifting motor 439, a pickup solenoid 433, and a clamp solenoid 434 are connected to the output port of the CPU 100. The CPU 100 controls loads such as various motors and solenoids connected to the output port according to a program stored in the ROM 110 based on the state of these sensors.

  In addition, the CPU 100 includes a serial interface unit (I / O) 130, exchanges control data with the control unit 440 of the apparatus main body 500 </ b> A of the copying machine, and via the serial interface unit (I / O) 130. Each unit is controlled based on control data sent from the control unit 440 of the copying machine main body 500A.

  Since the copying machine main body 500A grasps the size of the sheet discharged from the sheet discharge unit 208, the CPU 100 of the sheet processing apparatus 400 performs serial communication with the control unit 440 of the copying machine main body 500A. The size of the sheets stacked on the processing tray 410 can be grasped.

Therefore, each time the sheet S is discharged from the copying machine main body 500A, the CPU 100 of the sheet processing apparatus 400 grasps the size of the sheet S and controls the offset motor 432 so that the offset roller 407 moves in the sheet width direction. It is possible to control the movement amount to be a movement amount according to the sheet size. As a result, the offset roller 407 moves by an amount corresponding to the size of the sheet discharged onto the processing tray 410, and can reliably press the side edge of the sheet S against the width direction positioning wall 416.

  In the present embodiment, since the sheet bundle stacked on the stack tray 421 constitutes a part of the processing tray 410, when the sheet bundle SA is discharged from the processing tray 410, the stack tray 421 The stacked tray elevating motor 439 (see FIG. 10) is lowered until the uppermost surface of the stacked sheet bundle SA substantially coincides with the processing tray 410.

  By the way, the processing tray 410 is formed with, for example, a notch portion 410a that is an upstream end receiving portion in which the rear end portion (upstream end portion in the sheet conveying direction) of the sheet can slightly enter in the vicinity of the regulating member 411. (FIGS. 3 and 12).

  The sheet with the leading edge or the trailing edge curled downward with respect to the conveyance direction is discharged to the processing tray 410 and then conveyed to the downstream side in the sheet conveyance direction by the offset roller 407. Thereafter, the offset roller The sheet is conveyed toward the sheet trailing edge stopper 411 by the rotation stop and reverse rotation of 407.

  Here, when the sheet is conveyed toward the sheet trailing edge stopper 411, the trailing edge of the curled preceding sheet S1 enters the cutout portion 410a of the processing tray 410 and is aligned by hitting the sheet trailing edge stopper 411 ( FIG. 12 (a)). Then, when the next succeeding sheet S2 is also conveyed to the processing tray 410 and similarly conveyed toward the sheet rear end stopper 411 by the reverse rotation of the offset roller 407, it enters the notch portion 410a of the processing tray 410 and the rear end. Is abutted against the sheet trailing edge stopper 411 and aligned. At this time, the succeeding sheet S2 does not push and shift the preceding sheet S1 as in the case where there is no notch portion 410a as shown in FIGS. 11A and 11B (FIG. 12B). .

  In addition, a notch portion 410b in which the side end portion of the sheet (end portion along the sheet conveying direction) can slightly enter is formed in the vicinity of the width direction positioning wall 416 of the processing tray 410. (FIG. 4). The notches 410a and 410b are orthogonal to each other.

  After the sheet curled downward at the side edge along the conveyance direction, the sheet is discharged to the processing tray 410 and the trailing edge is abutted against the sheet trailing edge stopper 411 by the offset roller 407 to align the trailing edge. The sheet is moved in a direction intersecting the sheet conveying direction (sheet width direction) and abutted against the width direction positioning wall 416 to align the side ends.

  At this time, the curled side end portion enters the notch portion 410b of the processing tray 410 and abuts against the width direction positioning wall 416 to be aligned. Then, the next succeeding sheet S2 is also moved by moving the processing tray 410 in the width direction and enters the notch portion 410b, and the side end is abutted against the width direction positioning wall 416 and aligned. Unlike the case where the notched portion 410b is not provided, the succeeding sheet S2 to be aligned is not pushed and shifted.

  As described above, the sheet processing apparatus 400 of the present embodiment can stably align the sheet S with the leading end or the trailing end curled downward in the conveyance direction with a simple configuration. Further, it is possible to stably align the sheet with the side end along the conveying direction curled downward.

  Next, the configuration diagrams shown in FIGS. 1 to 9 and 12, the block diagram showing the configuration of the control unit of the sheet processing apparatus 400 shown in FIG. 10, and the operation of the sheet processing apparatus shown in FIGS. 13 and 14 will be described. The operation of the sheet processing apparatus will be described on the basis of the flowchart to be performed.

  First, when an image forming operation is started by the copying machine main body 500A, the CPU 100 (see FIG. 10) of the sheet processing apparatus 400 checks whether a sheet discharge signal is received from the copying machine main body 500A. (S100). Here, when the CPU 100 receives the sheet discharge signal (YES in S100), the CPU 100 turns on the pickup solenoid 433 (S110) and pulls up the offset roller 407 supported by the offset roller arm 406.

  Next, the CPU 100 turns on the conveyance motor 431 (S120) so that the conveyance roller 405 installed in the middle of the sheet discharge path can convey the sheet in the same direction as the sheet discharge direction of the copying machine main body 500A. To do. Here, the first sheet reaches the conveying roller 405 with the inlet sensor 403 turned on at the leading end (YES in S130). When the sheet is separated from the sheet discharge unit 208 (see FIG. 1) of the copying machine main body 500A by the transport roller 405 (YES in S140), the sheet is delivered to the sheet processing apparatus.

  Next, the CPU 100 turns off the pickup solenoid 433 while the sheet is not completely removed from the conveying roller 405 while conveying the sheet to the processing tray 410 by the conveying roller 405 (S150). The offset roller 407 is landed on the sheet by its own weight. Thereafter, as shown in FIG. 6A, the CPU 100 causes the offset roller 407 to convey the sheet S to a predetermined position (S160). Then, when the sheet S is conveyed to a predetermined position (YES in S160), the CPU 100 stops the rotation of the conveyance motor 431 (S170) and stops the conveyance of the sheet S.

  Next, when the rotation of the offset roller 407 stops, the CPU 100 turns on the clamp solenoid 434 (S180), and as shown in FIG. 6B, the sheet clamp installed near the sheet trailing edge stopper 411. Open member 412. Thereafter, the CPU 100 rotates the conveyance motor 431 in the direction opposite to the conveyance direction, pulls back the sheet S by the offset roller 407 (S190), and abuts the trailing edge of the sheet against the sheet trailing edge stopper 411.

  Note that the rotation amount of the offset roller 407 when the trailing edge of the sheet abuts against the trailing edge stopper 411 takes into account the skew of the sheet S that occurs when the sheet S is fed from the copying machine main body 500A. Is controlled by the CPU 100 so that it can be transported slightly more than the distance from the point of stopping and switching back to the sheet trailing edge stopper 411.

  At this time, for example, if the rear end of the sheet S1 is curled downward, the rear end of the sheet S1 enters the notch 410a of the processing tray 410 when the sheet S1 is conveyed toward the sheet rear end stopper 411. The sheet is aligned by abutting against the sheet rear end stopper 411. Then, after a series of operations described later, the next succeeding sheet S2 is conveyed to the processing tray 410. Similarly, when the succeeding sheet S2 is also conveyed toward the sheet trailing edge stopper 411 by the reverse rotation of the offset roller 407, the trailing edge enters the notch portion 410a of the processing tray 410 and hits the sheet trailing edge stopper 411. It is aligned with.

  Next, the CPU 100 checks the sheet size to be discharged based on the size information from the apparatus main body 500A of the copying machine (S200), and discharges the offset movement amount according to the size of the discharged sheet S, that is, discharged onto the processing tray 410. The movement distance in the width direction of the sheet S required to press the sheet S against the width direction positioning wall 416 is calculated (S210).

  Then, the CPU 100 offsets the offset roller 407 to the width direction positioning wall 416 via the pinion 435 and the rack 436 by the offset motor 432 as shown in FIG. 6C (S220). Here, when the offset roller 407 moves, the sheet S in contact with the offset roller 407 moves together with the offset roller 407 toward the width direction positioning wall 416 by the frictional force of the offset roller 407. At this time, the sheet clamp member 412 is opened as shown in FIG. 8B so as not to be a load of movement of the sheet S.

  Next, the offset roller 407 abuts the sheet S against the width-direction positioning wall 416, and then moves and stops slightly while sliding on the sheet S. Thereafter, the CPU 100 reversely reverses the offset roller 407 and pulls back the sheet S in order to correct misalignment of the trailing edge of the sheet caused by the offset movement of the sheet (S230). As a result, the rear end of the first sheet S is realigned, and the sheet alignment is completed.

  Next, when the alignment of the first sheet S is completed in this way, the CPU 100 turns on the pickup solenoid 433 (S240) and then raises the offset roller 407 as shown in FIG. 7A. Then, the clamp solenoid 434 is turned off (S250). As a result, the sheet clamp member 412 is closed as shown in FIG. 7B, and the aligned sheet S is sandwiched and held by the sheet clamp member 412. As a result, it is possible to prevent the first discharged sheet S1 from being transported downstream in the sheet conveying direction by the subsequent sheet S2 discharged next.

  Next, as shown in FIG. 7B, the offset roller 407 is returned to the home position via the pinion 435 and the rack 436 by the offset motor 432 while being lifted (S260).

  The CPU 100 checks whether or not the sheet S accommodated on the processing tray 410 is the last sheet corresponding to the last page of the copied document (S270), and based on the information sent from the copying machine main body 500A. If it is determined that the sheet is not the final sheet S (NO in S270), the process returns to S100 to receive a sheet discharge signal sent from the apparatus main body 500A of the copier, and the final sheet S is processed in the processing tray. The above-described flow is repeated until loaded on 410.

  Thereby, the CPU 100 of the sheet processing apparatus 400 grasps the size of the sheet S each time the sheet S is discharged from the apparatus main body 500A of the copying machine, and calculates an offset movement amount suitable for the sheet S. Based on the offset movement amount, the offset roller 407 is moved to align the side edge of the sheet with the width direction positioning wall 416.

  If the CPU 100 determines that the sheet is the final sheet (YES in S270), a sheet bundle corresponding to the copy document is formed on the processing tray 410. Next, whether or not the stapling process is selected is determined. (S280), and if it is selected (YES in S280), the staple unit 420 is driven to execute the stapling process (S290).

  When the stapling process is not selected (NO in S280), or when the stapling process is completed (S290), the CPU 100 holds the sheet bundle SA with the sheet clamp member 412 as shown in FIG. 413 is advanced toward the stack tray 421 by the sheet bundle discharge motor 430, and the sheet bundle SA is discharged and moved (S300).

  Next, when the sheet bundle discharge member 413 reaches the sheet bundle discharge position, the CPU 100 turns on the clamp solenoid 434 and rotates the sheet clamp member 412 that has gripped the sheet bundle SA upward, thereby causing the sheet bundle SA to move upward. To release.

  Next, the CPU 100 moves (lowers) the stack tray 421 in accordance with the discharge operation of the sheet bundle SA (S310), and then returns the sheet bundle discharge member 413 to the home position (S320).

  Thereafter, the CPU 100 stops the conveyance motor 431 to stop the rotation of the conveyance roller 405 and the offset roller 407 (S330), and turns off the pickup solenoid 433 (S340), thereby lowering the offset roller 407 and performing a series of processing. finish.

  In this embodiment, in order to bind the sheet bundle, a fixed stapler disposed near the width direction positioning wall 416 is used. However, when a movable stapler is used, the sheet bundle It is also possible to carry out stapling at different places or a plurality of places.

  In the sheet processing apparatus according to the present embodiment, the offset roller 407 is used to align the rear end and the side end of the sheet S. However, instead of the roller member, the member itself moves in the sheet conveyance direction and the sheet is moved. The same effect can be obtained by using a sheet conveying direction moving means for conveying the sheet and a sheet orthogonal direction moving means for moving the sheet in the width direction by moving in the direction (width direction) orthogonal to the sheet conveying direction.

  Furthermore, the sheet processing apparatus according to the present embodiment stores a program corresponding to the control procedure shown in the flowcharts of FIGS. 13 and 14 on the ROM 110 and performs control while the CPU 100 reads the program. The same effect can be obtained even if the above processing is performed by hardware.

1 is a schematic front view of a copying machine including a sheet processing apparatus according to an embodiment of the present invention in an apparatus main body. 1 is a schematic front view of a sheet processing apparatus according to an embodiment of the present invention. It is an enlarged front view of the principal part of the sheet processing apparatus in the embodiment of the present invention. 1 is a schematic plan view of a sheet processing apparatus in an embodiment of the present invention. FIG. 3 is a schematic front view of a drive mechanism for an offset roller, a conveyance roller, a sheet bundle discharge member, and a sheet clamp member of the sheet processing apparatus in the embodiment of the present invention. It is a figure for demonstrating operation | movement of an offset roller, and the motion of a sheet accompanying it. (A) is a figure of the state which has conveyed the sheet | seat discharged | emitted by the processing sheet once to the downstream side. (B) is a diagram showing a state where the sheet is conveyed back to the upstream side following (a). (C) is a figure of the state which has moved the sheet | seat to the width direction following (b). FIG. 7 is a diagram for explaining the operation following FIG. 6. (A) is a figure of the state which separated the offset roller from the sheet | seat following Fig.6 (a). (B) is the figure which returned the offset roller to the initial position following (a). It is a figure when a sheet clamp member has not pinched the sheet. (A) is a figure of the state which the sheet | seat contact | abutted to the rear-end stopper. (B) is a figure of the state which the sheet | seat contact | abutted to the width direction alignment positioning wall. FIG. 10 is a diagram for explaining an operation in which a sheet bundle discharge member discharges a sheet bundle to a stack tray. 3 is a block diagram illustrating a configuration of a control unit of the sheet processing apparatus. FIG. FIG. 6 is a diagram illustrating a state in which sheets with a sheet end curled downward are aligned in a sheet processing apparatus without a notch in a processing tray. FIG. 6A is a diagram of a state when the first sheet is stacked on the processing tray. FIG. 6B is a diagram illustrating a state where the second sheet is stacked on the processing tray. It is a figure which shows a mode that the sheet | seat in which the edge part of the sheet | seat curled downward is aligned in the sheet processing apparatus of this invention. FIG. 6A is a diagram of a state when the first sheet is stacked on the processing tray. FIG. 6B is a diagram illustrating a state where the second sheet is stacked on the processing tray. 6 is a flowchart for explaining a part of the sheet processing operation of the sheet processing apparatus. It is a flowchart following FIG. It is a schematic front view of the conventional sheet processing apparatus.

Explanation of symbols

S sheet S1 preceding sheet S2 succeeding sheet 100 CPU of sheet processing apparatus
200 Printer unit (image forming means)
400 Sheet processing device 407 Offset roller (sheet conveying means)
410 processing tray (sheet stacking means)
410a Notch (upstream end receiving part)
410b Notch (side end receiving part)
411 Sheet rear end stopper (upstream end receiving means)
416 Width direction positioning wall (side end receiving means)
420 Stapler unit 421 Stack tray 440 Control unit 500 of copying machine main body Copying machine (image forming apparatus)
500A Copier (image forming device) main unit

Claims (2)

Sheet stacking means for stacking sheets transported in a predetermined transport direction;
A sheet conveying means that contacts the sheet fed to the sheet stacking means and is capable of conveying the sheet in an upstream direction opposite to the conveying direction and a direction intersecting the conveying direction ;
An upstream end aligning unit that is provided upstream of the sheet stacking unit in the transport direction and aligns the sheet by abutting the upstream end of the sheet transported to the upstream side in the transport direction by the sheet transport unit;
A side end aligning unit that aligns the sheet by abutting a side end along the transport direction of the sheet transported in a direction intersecting the transport direction by the sheet transport unit;
A notch portion provided upstream of the sheet stacking means in the transport direction and into which an upstream end of a sheet transported for alignment enters;
Provided on the seat upstream side in the conveying direction of and the sheet stacking means in the vicinity of the side edge aligning means, a staple processing section upstream end performs staple processing on the upstream end of the sheet has entered the notch, the Prepared,
The sheet conveying means conveys a plurality of sheets fed to the sheet stacking means one by one to the upstream side in the conveying direction, and causes the upstream end of the sheet to enter the notch, After abutting the upstream end against the upstream end aligning means, the sheet is transported in a direction intersecting the transport direction, and the side edge of the sheet along the transport direction is thrust against the side end aligning means. A sheet bundle is formed on the sheet stacking means by applying and aligning the sheets;
The stapling unit performs a stapling process on an upstream end of the sheet bundle aligned on the sheet stacking unit;
A sheet processing apparatus. 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 claim 1 ,
An image forming apparatus.

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