JP2013001459A - Sheet processing device, image forming system, sheet processing method, and sheet processing control program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress expansion of a sheet between pressing members to achieve good aligning accuracy.SOLUTION: A curl quantity of a bundle of sheets placed on an end-face stapling tray is detected (S104). If the curl quantity is smaller than a prescribed value, the bundle of sheets is pressed by simultaneously operating first to third rear-end presser levers (S106). If the curl quantity is the prescribed value or more and a stapling mode is one-point stapling, a first rear-end presser lever positioned at a central part on a side far from a stapling position is operated firstly to press the bundle of sheets, and then a third rear-end presser lever close to the stapling position is operated to press the bundle of sheets (S111). If the stapling mode is two-point stapling, the first rear-end presser lever positioned at the central part far from the stapling positions is operated firstly to press the central part of the bundle of sheets, and then the second and third rear-end presser levers respectively positioned on both end parts and close to the stapling positions are operated to press end parts of the bundle of sheets (S112).

Description

  The present invention relates to a sheet processing apparatus for aligning a sheet-like recording medium (in the present specification, simply referred to as “sheet”) such as paper, recording paper, transfer paper, and OHP sheet, and copying with the sheet processing apparatus. BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming system including an image forming apparatus such as a printer, a printer, a facsimile machine, or a digital multifunction peripheral, a sheet processing method executed by the sheet processing apparatus, and a sheet processing control program.

  2. Description of the Related Art Conventionally, a stapler that stacks sheets discharged from an image forming apparatus on a staple tray, aligns the conveyance direction (so-called vertical direction) and the direction orthogonal to the conveyance direction (so-called width direction), and then binds the stapler. An apparatus called a finisher provided is known. When performing end face binding with a stapler, the sheet is abutted against a rear end reference fence that defines a position in the sheet conveyance direction, and end face binding is performed while being held. At that time, the stapler can move in the direction orthogonal to the paper transport direction along the paper edge (usually the paper rear edge) to change the binding position.

  Such a finisher is provided with a pressing member that presses the sheet bundle in the thickness direction in order to maintain the posture of the trailing edge of the sheets stacked on the staple tray in order to improve the finishing alignment accuracy of the bound sheet bundle. (For example, Patent Document 1).

  In the invention described in Japanese Patent Laid-Open No. 2002-321868, the sheet is discharged from the image forming apparatus in order to improve the lateral sheet alignment by the jogger with respect to the sheet having the side face curl. A staple tray for receiving and stacking sheets to be stacked, a rear end fence for aligning sheets by abutting an end portion in the conveyance direction of the sheets stacked on the staple tray, and an end of the sheet bundle aligned by the rear end fence In the sheet processing apparatus provided with a stapler for performing a stapling process in the unit, means for correcting the bending of the edge parallel to the sheet conveyance direction is provided on the sheet stacking surface of the staple tray.

  However, in the invention described in Patent Document 1, since the pressing member presses the sheet at the same time, the sheet may swell between the pressing members, and the sheet may bend between the pressing member and the pressing member. When the sheet is bent in this manner, the binding accuracy is lowered, the stapling position is shifted or varied, and the alignment accuracy of the sheets after binding is deteriorated.

  Therefore, the problem to be solved by the present invention is to suppress the swelling of the sheet between the pressing members and obtain a good alignment accuracy.

In order to solve the above-described problem, the first means aligns the sheet conveying direction with the sheet accommodating means for accommodating the sheet and the rear end portion in the conveying direction of the sheet accommodated on the sheet accommodating means. Alignment means; at least two pressing means provided in the main scanning direction for pressing the sheet bundle aligned on the sheet storage means by the alignment means; and binding means for binding the sheet bundle pressed by the pressing means; And the pressing means is a sheet processing apparatus, comprising: a pressing control means for operating the pressing means far from the binding position among the pressing means first, and then operating the pressing means on the near side. It is characterized by being.
The second means is characterized by an image forming system including the sheet processing apparatus according to the first means.
The third means includes a step of storing the sheet in the sheet storing means, a step of abutting the rear end portion in the transport direction of the sheet stored in the storing step on the aligning means, and aligning the transport direction of the sheet, A step of pressing the sheet bundle on the sheet storage means aligned in the aligning step by pressing means provided in at least two in the main scanning direction, a step of binding the sheet bundle pressed in the pressing step by the binding means, The pressing step includes the step of first operating the pressing means far from the binding position among the at least two pressing means, and then operating the pressing means on the near side. And a process.
The fourth means includes a procedure for storing the sheet in the sheet storing means, a procedure for abutting the rear end portion in the transport direction of the sheet stored according to the storing procedure to the aligning means, and aligning the transport direction of the sheet, A procedure for pressing the sheet bundle on the sheet storage means aligned according to the alignment procedure by pressing means provided in at least two in the main scanning direction; a procedure for binding the sheet bundle pressed according to the pressing procedure by the binding means; A sheet processing control program for causing a computer to execute sheet processing control according to the procedure, wherein the pressing step includes the pressing unit far from the binding position among the at least two pressing units provided first. And a procedure for operating the pressing means on the near side.

  According to the present invention, it is possible to suppress the swelling of the sheet between the pressing members, and to obtain good alignment accuracy.

1 is a system configuration diagram illustrating a system including a sheet post-processing apparatus and an image forming apparatus as a sheet processing apparatus according to an embodiment of the present invention. It is the schematic block diagram which looked at the end surface binding processing tray in FIG. 1 from the stacking surface side of the tray. It is a perspective view which shows schematic structure of the end surface binding processing tray in FIG. 1, and its attachment mechanism. It is a side view which shows operation | movement of the discharge | release belt in FIG. It is a perspective view which shows the moving mechanism of the stapler in FIG. FIG. 5 is a diagram illustrating a relationship among sheets stacked on an end surface binding processing tray, a reference fence, and an end surface binding stapler during end surface binding. It is a principal part enlarged view of a rear-end holding | maintenance mechanism, and shows the rear-end reference | standard fence part in FIG. It is the figure which looked at the rear-end holding | maintenance mechanism from the perpendicular | vertical direction with respect to the end surface binding processing tray. It is the figure which looked at the rear end pressing mechanism from the direction parallel to the end face binding processing tray. It is a perspective view which shows the moving mechanism of the direction orthogonal to the sheet conveyance direction of a rear-end reference fence. 3 is a block diagram illustrating a control configuration of an image forming system including a sheet post-processing apparatus and an image forming apparatus. FIG. It is a flowchart which shows the process sequence of the binding process performed with a sheet | seat post-processing apparatus.

  In the present invention, in the sheet aligning operation by the pressing unit during the binding process with the staple tray, the pressing unit far from the binding position presses the sheet bundle, and then the pressing unit closer to the binding position presses the sheet bundle. Further, it is characterized in that the curling of the sheet edge at the time of pressing the trailing edge is corrected and the swelling of the sheet between the pressing members is suppressed.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a diagram illustrating a system configuration of a system including a sheet post-processing apparatus PD and an image forming apparatus PR as a sheet processing apparatus according to the present embodiment.

  In FIG. 1, an image forming apparatus PR is an image processing circuit that converts input image data into printable image data, and an optical writing apparatus that performs optical writing on a photoconductor based on an image signal output from the image processing circuit. A developing device for developing the latent image formed on the photosensitive member by optical writing, a transfer device for transferring the toner image visualized by the developing device to the sheet, and a fixing device for fixing the toner image transferred on the sheet At least the sheet on which the toner image is fixed is sent to the sheet post-processing apparatus PD, and desired post-processing is performed by the sheet post-processing apparatus PD. Here, the image forming apparatus PR is of an electrophotographic system as described above, but any known image forming apparatus such as an ink jet system or a thermal transfer system can be used. In this embodiment, the image processing circuit, the optical writing device, the developing device, the transfer device, and the fixing device constitute image forming means.

  The sheet post-processing apparatus PD is attached to a side portion of the image forming apparatus PR, and the sheet discharged from the image forming apparatus PR is guided to the sheet post-processing apparatus PD. The sheet post-processing apparatus PD includes a conveyance path A, a conveyance path B, a conveyance path C, a conveyance path D, and a conveyance path H, and the sheet is a post-processing unit (in this embodiment) that performs post-processing on a single sheet. It is first transported to a transport path A having a punch unit 100) as a punching means.

  The conveyance path B is a conveyance path that leads to the upper tray 201 through the conveyance path A, and the conveyance path C is a conveyance path C that leads to the shift tray 202. The conveyance path D is a conveyance path D that leads to a processing tray F that performs alignment, stapling, and the like (hereinafter also referred to as an “end face binding processing tray”). The conveyance path A is distributed to the conveyance paths B, C, and D by the branch claw 15 and the branch claw 16, respectively.

  In this sheet post-processing apparatus, punching (punching unit 100), sheet alignment + edge binding (jogger fence 53, end surface binding stapler S1), sheet alignment + saddle binding (saddle stitch upper jogger fence 250a, Each process such as saddle stitching lower jogger fence 250b, saddle stitching stapler S2), sheet sorting (shift tray 202), and folding (folding plate 74, folding roller 81) can be performed. Therefore, the transport path A, the subsequent transport path B, the transport path C, and the transport path D are selected. Further, the conveyance path D includes a sheet storage portion E, and an end face binding processing tray F, a saddle stitching middle folding processing tray G, and a paper discharge conveyance path H are provided on the downstream side of the conveyance path D.

  In the conveyance path A common to the upstream of the conveyance path B, the conveyance path C, and the conveyance path D, an inlet sensor 301 that detects a sheet received from the image forming apparatus PR, an inlet roller 1, a punch unit 100, The punch and waste container 101, the transport roller 2, the first and second branching claws 15, and the branching claws 16 are sequentially arranged. The first and second branch claws 15 and 16 are held in the state of FIG. 1 by a spring (not shown) (initial state), and the branch claws 15 and 16 are turned on by turning on the first and second solenoids (not shown). Are driven to select ON / OFF of the first and second solenoids. By this selection, the combination of the branch directions of the first and second branch claws 15 and 16 is changed, and the sheet is distributed to the transport path B, the transport path C, and the transport path D.

  When the sheet is guided to the conveyance path B, the state shown in FIG. 1, that is, the first solenoid remains OFF (the first branch claw 15 is in the initial state). As a result, the sheet is discharged from the conveying roller 3 to the upper tray 201 via the paper discharge roller 4.

  When the sheet is guided to the conveyance path C, the first and second solenoids are turned on from the state shown in FIG. 1 (the second branch claw 16 is in the initial state), so that the branch claw 15 branches upward. The nail | claw 16 will be in the state which each rotated below. Thus, the sheet is conveyed to the shift tray 202 side through the conveying roller 5 and the discharge roller pair 6 (6a, 6b). In this case, the sheets are sorted. Sheets are sorted by a shift tray paper discharge unit located at the most downstream portion of the sheet post-processing apparatus PD. Sheets are sorted by the shift paper discharge roller pair 6 (6a, 6b), the return roller 13, and the paper surface. The detection sensor 330, the shift tray 202, a shift mechanism (not shown) that reciprocates the shift tray 202 in a direction orthogonal to the sheet conveying direction, and a shift tray lifting mechanism that lifts and lowers the shift tray 202 are performed.

  When the sheet is guided to the conveyance path D, the branching claw 15 is moved upward by turning on the first solenoid that drives the first branching claw 15 and turning off the second solenoid that drives the second branching claw. Further, the branching claw 16 is turned upward, and the sheet is guided from the conveying roller 2 to the conveying path D through the conveying roller 7. The sheet guided to the conveyance path D is guided to the end surface binding processing tray F, and the sheet subjected to alignment, stapling, and the like in the end surface binding processing tray F is guided to the shift tray 202 by the guide member 44. The sheet is fed to the saddle stitching / saddle folding processing tray G (hereinafter also simply referred to as “saddle stitching processing tray”). When guided to the shift tray 202, the sheet bundle is discharged from the discharge roller pair 6 to the shift tray 202. The sheet bundle guided to the saddle stitching processing tray G side is folded and bound by the saddle stitching processing tray G, and is discharged from the paper discharge roller 83 to the lower tray 203 through the paper discharge conveyance path H.

  On the other hand, a branching claw 17 is disposed in the conveyance path D, and is held in the state shown in the figure by a low load spring (not shown). After the trailing edge of the sheet conveyed by the conveyance roller 7 passes through the branching claw 17. At least the transport roller 9 among the transport rollers 9 and 10 and the staple paper discharge roller 11 can be reversed to reverse the sheet along the turn guide 8. As a result, the sheet is guided from the rear end of the sheet to the sheet storage portion E to be retained (pre-stacked), and can be conveyed while being overlapped with the next sheet. By repeating this operation, two or more sheets can be stacked and conveyed. Reference numeral 304 denotes a prestack sensor for setting a reverse feed timing when the sheets are prestacked.

  When the sheet is guided to the conveyance path D and the sheet alignment and the edge binding are performed, the sheets guided to the end surface binding processing tray F by the staple discharge roller 11 are sequentially stacked on the end surface binding processing tray F. In this case, alignment in the vertical direction (sheet conveyance direction) is performed by the tapping roller 12 for each sheet, and alignment in the horizontal direction (direction perpendicular to the sheet conveyance direction: sheet width direction) is performed by the jogger fence 53. The end face binding stapler S1 as the binding means is driven by a staple signal from a control device (not shown) between the end of the job, that is, from the last sheet of the sheet bundle to the first sheet of the next sheet bundle, and the binding process is performed. The sheet bundle that has been subjected to the binding process is immediately sent to the shift paper discharge roller 6 by the discharge belt 52 (see FIG. 2) on which the discharge claw 52a protrudes, and discharged to the shift tray 202 set at the receiving position. Is done.

  As shown in FIG. 1, the end-face stitching stapler S1 includes a stitcher (driver) S1a for ejecting staples and a clincher S1b for bending the leading end of the staples, and the trailing end reference that serves as an alignment reference for the trailing end of the sheet. Since the fence 51a, 51b is a space portion S1c through which the end face binding stapler S1 and the rear end reference fences 51a, 51b do not interfere with each other, the end face binding stapler S1 moves. Further, unlike the saddle stitching stapler S2, the end face stitching stapler S1 includes a stitcher S1a and a clincher S1b. The stitcher S1a functions as a fixed side without moving in the direction perpendicular to the sheet surface, and functions as a moving side in which the clincher S1b moves in a direction perpendicular to the sheet surface. Thus, when performing the binding operation on the sheet bundle SB, the clincher S1b moves to a stitcher S1a side in a predetermined binding portion of the sheet bundle SB that is in contact with the stack surfaces 51a1 and 51b1 of the reference fence 51. In this process, a binding operation is performed.

  As shown in FIGS. 2 and 4, the discharge belt 52 is positioned at the center of alignment in the sheet width direction, is stretched between pulleys 62, and is driven by a discharge belt drive motor 157. A plurality of discharge rollers 56 are arranged symmetrically with respect to the discharge belt 52, are provided so as to be rotatable with respect to the drive shaft, and function as driven rollers.

  The release claw 52 a is configured such that the home position is detected by a release belt HP sensor 311, and this release belt HP sensor 311 is turned on / off by a discharge claw 52 a provided on the discharge belt 52. Two discharge claws 52a are arranged at opposing positions on the outer periphery of the discharge belt 52, and the sheet bundle stored in the end face binding processing tray F is moved and conveyed alternately. Further, if necessary, the discharge belt 52 is rotated in the reverse direction, and the discharge claw 52a waiting to move the sheet bundle from now on and the back side of the discharge claw 52a on the opposite side of the sheet bundle accommodated in the end face binding processing tray F It is also possible to align the tips in the transport direction.

  In FIG. 1, reference numeral 110 denotes a rear end pressing lever, which is positioned at the lower end portion of the rear end reference fence 51 so that the rear end of the sheet bundle SB accommodated in the rear end reference fence 51 can be pressed. It reciprocates in a direction substantially perpendicular to the end face binding processing tray F. Sheets discharged to the end surface binding processing tray F are tapped for each sheet and aligned in the vertical direction (sheet conveying direction) with the rollers 12, but the trailing edge of the sheets stacked on the end surface binding processing tray F is curled. When the waist is weak, the rear end tends to buckle and swell due to the weight of the seat itself. Further, as the number of stacked sheets increases, the gap for the next sheet in the rear end reference fence 51 is reduced, and the vertical alignment tends to be deteriorated. Therefore, the trailing edge pressing mechanism 110 reduces the swelling of the trailing edge of the sheet so that the sheet can easily enter the trailing edge reference fence 51, and the trailing edge pressing lever 110 directly presses the sheet.

  In FIG. 1, reference numerals 302, 303, 304, 305, 306, and 310 denote sheet detection sensors that detect whether or not a sheet has passed at a provided position or whether or not a sheet is stacked. Reference numeral 306 denotes a staple discharge sensor described later.

  FIG. 2 is a schematic configuration diagram of the end face binding processing tray F as viewed from the tray stacking surface side, and corresponds to the case of viewing from the right side surface of FIG. In the drawing, the alignment in the width direction of the sheet received from the upstream image forming apparatus PR is performed by jogger fences 53a and 53b, and the vertical direction is the first and second rear end reference fences 51a and 51b (in FIG. 1). (Matched by reference numeral 51). FIG. 6 shows the relationship between the sheets stacked on the end surface binding processing tray F at the time of end surface binding, the reference fences 51a and 51b, and the end surface binding stapler S1, and the first and second rear end references. The fences 51a and 51b are respectively provided with stack surfaces 51a1, 51a2, 51b1, and 51b2 that hold the sheet rear end ST in contact with each other and support the sheet rear end ST. As can be seen from FIG. 2, the support can be performed at four points. However, in the case of one-face oblique binding, the end-face stitching stapler S1 moves to the end of the stacked sheet bundle SB, and the binding process is performed at an oblique angle. I do. FIG. 6B shows a relationship between the staple S1d after binding and the rear end fence 51b. At that time, as shown in FIG. 6A, the sheet bundle SB is stacked in contact with any two of the stack surfaces 51a1, 51a2, 51b1 of the rear end fence 51. This is because of mechanical errors including the accuracy of attaching the rear end fences 51a and 51b, and is supported in a stable state by being supported at two points.

  After completion of the alignment operation, binding processing is performed by the end-face binding stapler S1, and the discharge belt 52 is driven counterclockwise by the discharge belt drive motor 157, as can be seen from the perspective view showing the operation of the discharge belt in FIG. The sheet bundle after the binding process is scooped by the discharge claw 52a attached to the discharge belt 52 and discharged from the end face binding processing tray F. Reference numerals 64a and 64b are a front side plate and a rear side plate. Further, this operation can be performed in the case of an unbound bundle that is not subjected to the binding process after the alignment process.

  FIG. 3 is a perspective view showing a schematic configuration of the end face binding processing tray F and its attached mechanism. As shown in the drawing, the sheets guided to the end-face binding processing tray F by the staple paper discharge roller 11 are sequentially stacked on the end-face binding processing tray F. At this time, when the number of sheets discharged to the end face binding processing tray F is one, the sheet is aligned in the vertical direction (sheet conveying direction) with the tapping roller 12 for each sheet, and the jogger fences 53a and 53b are used in the width direction. Matching is done. The hitting roller 12 is given a pendulum motion by the hitting SOL 170 about the fulcrum 12a and intermittently acts on the sheet fed to the end face binding processing tray F to abut the sheet rear end ST against the rear end reference fence 51. The hitting roller 12 itself rotates counterclockwise. The jogger fence 53 is provided with a pair of front and rear (53a, 53b) as shown in FIGS. 2 and 3, and is driven by a jogger motor 158 capable of forward and reverse rotation through a timing belt to reciprocate in the sheet width direction.

  FIG. 5 is a side view showing the stapler moving mechanism. As shown in FIG. 5, the end-face binding stapler S1 is driven via a timing belt 159a by a stapler moving motor 159 capable of forward and reverse rotation, and moves in the sheet width direction in order to bind a predetermined position at the rear end of the sheet. A stapler movement HP sensor 312 that detects the home position of the end face binding stapler S1 is provided at one end of the moving range. The binding position in the sheet width direction is the movement of the end face binding stapler S1 from the home position. Controlled by quantity. The end surface binding stapler S1 is configured to be capable of binding at one or a plurality of positions (generally two locations) at the rear end portion of the sheet, and at least over the entire width of the rear end ST of the sheet supported by the rear end reference fences 51a and 51b. It is movable. In addition, it is possible to move to the front side of the apparatus as much as possible for exchanging the staples, so that the user can exchange staple staples.

  A sheet bundle deflection mechanism I is provided on the downstream side in the sheet conveying direction of the end-face binding processing tray F. As shown in FIG. 1, a conveyance path for feeding the sheet bundle SB from the end face binding processing tray F to the saddle stitching processing tray G, and from the end face binding processing tray F to the shift tray 202, and a conveyance means for conveying the sheet bundle SB are: A conveyance mechanism 35 that applies a conveyance force to the bundle SB, a discharge roller 56 that turns the sheet bundle SB, and a guide member 44 that performs a guide for turning the sheet bundle SB.

  Each detailed configuration will be described. The driving force of the driving shaft 37 is transmitted to the roller 36 of the transport mechanism 35 by a timing belt. The roller 36 and the driving shaft 37 are connected and supported by an arm, and driven. The shaft 37 can be swung about the rotation fulcrum. The roller 36 of the transport mechanism 35 is driven to swing by a cam 40. The cam 40 rotates around a rotation shaft and is driven by a motor (not shown). In the transport mechanism 35, a driven roller 42 is disposed at a position opposite to the roller 36, and a sheet bundle is sandwiched between the driven roller 42 and the roller 36 and pressed by an elastic material to give a transport force.

  A conveyance path for turning the sheet bundle from the end face binding processing tray F to the saddle stitching processing tray G is formed between the discharge roller 56 and the inner surface of the guide member 44 on the side facing the discharge roller 56. The guide member 44 rotates around a fulcrum, and the drive is transmitted from the bundle branch drive motor 161 (see FIG. 2). When the sheet bundle is conveyed from the end surface binding processing tray F to the shift tray 202, the guide member 44 rotates in the illustrated clockwise direction around the fulcrum, and the outer surface of the guide member 44 (the surface not facing the discharge roller 56). ) And the outer guide plate function as a conveyance path. When the sheet bundle P is sent from the end surface binding processing tray F to the saddle stitching processing tray G, the rear end of the sheet bundle SB aligned in the end surface binding processing tray F is pushed up by the discharge claw 52a, and the roller 36 of the transport mechanism 35 and the roller 36 A sheet bundle is sandwiched between the opposed driven rollers 42 facing each other, and a conveying force is applied. At this time, the roller 36 of the transport mechanism 35 stands by at a position where it does not hit the leading end of the sheet bundle SB. Next, after the leading edge of the sheet bundle SB passes, the roller 36 of the transport mechanism 35 is brought into contact with the sheet surface to apply a transport force. At this time, the guide member 44 and the discharge roller 56 form a guide for the turn conveyance path, and convey the sheet bundle SB to the downstream saddle stitching processing tray G.

  As shown in FIG. 1, the saddle stitch processing tray G is provided on the downstream side of the sheet bundle deflection mechanism including the conveyance mechanism 35, the guide member 44, and the discharge roller 56. The saddle stitching processing tray G is provided substantially perpendicularly on the downstream side of the sheet bundle deflection mechanism, with the center folding mechanism at the center, the bundle conveyance guide plate upper 92 above, and the bundle conveyance guide below. A lower plate 91 is arranged.

  Further, an upper bundle conveying roller 71 is provided above the upper bundle conveying guide plate 92, and a lower bundle conveying roller 72 is provided below the upper bundle conveying guide plate 92. A saddle stitch upper jogger fence 250a is arranged on both sides along the side surface of 92. Similarly, a saddle stitch lower jogger fence 250b is provided on both sides along the side surface of the bundle conveyance guide plate lower 91, and the saddle stitch stapler S2 is disposed at a place where the saddle stitch lower jogger fence 250b is installed. The saddle stitching upper jogger fence 250a and the saddle stitching lower jogger fence 250b are driven by a driving mechanism (not shown) and perform an alignment operation in a direction (sheet width direction) orthogonal to the sheet conveying direction. The saddle stitch stapler S2 is a pair of a clincher portion and a driver portion, and two pairs are provided at a predetermined interval in the sheet width direction.

  In addition, a movable reference fence 73 is disposed so as to cross the lower bundle conveyance guide plate 91 and can be moved in the sheet conveyance direction (vertical direction in the drawing) by a moving mechanism including a timing belt and its driving mechanism. As shown in FIG. 1, the drive mechanism includes a drive pulley and a driven pulley on which the timing belt is stretched, and a stepping motor that drives the drive pulley. Similarly, a rear end tapping claw 251 and its drive mechanism are provided on the upper end side of the upper bundle transport guide plate 92. The trailing edge tapping claw 251 can reciprocate in a direction away from the sheet bundle deflecting mechanism and a direction pushing the trailing edge of the sheet bundle (the side that contacts the trailing edge when the sheet bundle is introduced) by a timing belt 252 and a driving mechanism (not shown). ing.

  The center folding mechanism is provided at a substantially central portion of the saddle stitching processing tray G, and includes a folding plate 74, a folding roller 81, and a conveyance path H that conveys the folded sheet bundle. In FIG. 1, reference numeral 326 denotes a home position sensor for detecting the home position of the rear end tapping claw 251, reference numeral 323 denotes a folded portion passage sensor for detecting a folded sheet, and reference numeral 321 denotes a sheet bundle. A bundle detection sensor 322, which detects that the center folding position has been reached, is a movable reference fence home position sensor that detects the home position of the movable reference fence 73.

  In this embodiment, a detection lever 501 for detecting the stacking height of the sheet bundle SB folded in the lower tray 203 is provided to be swingable by a fulcrum 501a, and the angle of the detection lever 501 is determined by a paper surface sensor 505. Detecting and raising / lowering the lower tray 203 and detecting overflow.

  7 is an enlarged view of the main part of the rear end reference fence portion in FIG. 1 showing the rear end pressing mechanism in an enlarged manner, and FIG. 8 is a view of the rear end pressing mechanism as viewed from the direction perpendicular to the end surface binding processing tray F. FIG. 9 is a view of the rear end pressing mechanism as viewed from a direction parallel to the end surface binding processing tray F. FIG.

  In FIG. 7, the rear end holding levers 110 a, 110 b, and 110 c are provided in the direction facing the rear end reference fence 51. As can be seen from FIGS. 8 and 9, the rear end holding lever 110 is provided with first to third three in the sheet width direction. Each of the first to third rear end holding levers 110a, 110b, and 110c advances in the direction of the sheet bundle SB (arrows) via belts B1, B2, and B3 spanned between the motors M1, M2, and M3 and the pulleys. Y1 direction) and retreat (arrow Y direction) are possible, and the rear end of the sheet bundle SB is pressed when the sheet advances. The first to third rear end holding levers 110a, 110b, and 110c are supported so as to be slidable vertically with respect to the sheet bundle SB, and the rear ends are connected to the belts B1, B2, and B3, and the belts B1, B2 are supported. , B3 is moved linearly by the rotational movement of B3. Each rear end holding lever 110a, 110b, 110c has an independent configuration and is attached to the base member 110BS. In the present embodiment, three rear end pressing levers 110 are provided in the width direction of the sheet, but the number of rear end pressing levers 110 is appropriately set according to the specifications of the apparatus. Further, the drive mechanism of the rear end pressing lever 110 is not limited to the motor and the belt, and any mechanism that can mechanically press the sheet bundle SB is sufficient. Therefore, in FIG. 1, the rear end holding levers 110a, 110b, and 110c are collectively indicated by reference numeral 110.

  When curl (deflection) occurs in the width direction of the sheet bundle SB, as shown in FIG. 7, the sheet curls (deflection) by its own weight with the rear end of the sheet abutting against the rear end reference fence 51, or in the initial state Sheet bundles with curled ends are stacked and stacked in this curled state. In this state, the end face binding stapler S1 binds the sheet bundle SB. At that time, if the curled portion of the sheet bundle SB and the pressing position of the trailing edge pressing lever 110 coincide with each other, the curling can be corrected. However, depending on the sheet size, the pressed position differs from the curled portion, so that the staple position varies when pressed. During the stapling operation, the sheet bundle SB is crushed instantaneously and stapled. Therefore, if the bent portion and the pressed portion are deviated as described above, the deviation is the deviation of the binding portion of the sheet bundle SB. As a result, the sheet bundle SB after binding is poorly aligned.

  Further, as shown in FIG. 9, the first to third rear end pressing levers 110a1, 110b1, 110c1 having no driving source are provided at the front ends of the first to third rear end pressing levers 110a, 110b, 110c. 110a, 110b, and 110c can prevent the surface of the sheet bundle SB from being pressed.

  Further, in FIG. 8, reference numerals Se1 and Se2 are curl amount detection sensors. The curl amount detection sensors Se1 and Se2 are installed on both sides of the sheet bundle SB and optically detect the curl amount at the rear end of the sheet bundle SB. As the curl amount detection sensors Se1 and Se2, for example, reflection type optical sensors are used. When the detected curl amount is larger than a specified value, for example, the first rear end pressing lever 110a that presses the center portion presses the rear end portion of the sheet bundle SB, and then binds the sheet bundle SB (sheet bundle SB). The second and third rear end holding levers 110b and 110c located on the end side of the sheet press the sheet bundle SB (step S112 described later).

  7 and FIG. 8, the portion for pressing the sheet bundle SB of the rear end pressing lever 110 is different. However, the same portion is actually different only in the arrangement on the drawing for convenience of drawing. Press.

  Such control is executed by the control circuit of the sheet post-processing apparatus PD. FIG. 10 is a block diagram illustrating a control configuration of an image forming system including the sheet post-processing apparatus PD and the image forming apparatus PR. The sheet post-processing device PD includes a control circuit equipped with a microcomputer having a CPU_PD1, an I / O interface PD2, and the like. The CPU_PD1 includes a CPU of the image forming apparatus PR, each switch of the operation panel PR1, and each sensor (not shown). Is input via the communication interface PR2, and the CPU_PD1 executes predetermined control based on the input signal. Further, the CPU_PD 1 controls driving of the solenoid and the motor via the driver and the motor driver, and acquires sensor information in the apparatus from the interface. In addition, motor drive control is performed by the motor driver via the I / 0 interface PD2 in accordance with the control target and sensor, and sensor information is acquired from the sensor. The control is based on a program defined by the program code while the CPU_PD1 reads a program code stored in a ROM (not shown), develops it in a RAM (not shown), and uses the RAM as a work area and a data buffer. Executed.

  Further, the control of the sheet post-processing apparatus PD in FIG. 10 is executed based on an instruction or information from the CPU of the image forming apparatus PR. The user's operation instruction is issued from the operation panel PR1 of the image forming apparatus PR, and the image forming apparatus PR and the operation panel PR1 are connected to each other via a communication interface PR3. As a result, the operation signal from the operation panel PR1 is transmitted from the image forming apparatus PR to the sheet post-processing apparatus PD, and the processing state and functions of the sheet post-processing apparatus PD are notified to the user via the operation panel PR1. .

  FIG. 11 is a flowchart showing the processing procedure of the binding process executed by the CPU_PD1 of the sheet post-processing apparatus PD. In this processing procedure, when the processing is started, first, the sheet is conveyed to the end face binding processing tray F by conveying means such as the entrance roller 1, the conveying rollers 2, 7, 9, 10 and the staple discharge roller 11 ( Step S101). The sheet conveyed to the end surface binding processing tray F is struck by the tapping roller 12 toward the rear end reference fence 110 side, and alignment in the conveyance direction is performed. Thereafter, the sheet width direction is aligned by the jogger fences 53a and 53b (step S102). This process is repeated for the number of sheets corresponding to one copy (step S103: NO), and when the discharge of one part of the number of sheets is completed (step S103: YES), the curl amount detection sensors Se1 and Se2 are used on the rear end reference fence 51. The curl amount of the sheet bundle SB stacked on the sheet is detected (step S104).

  The CPU_PD1 compares the detected curl amount M with a preset specified value. If the curl amount M is smaller than the specified value (step S105: YES), the CPU_PD1 determines that the sheet bundle SB is thin, and after the first to third steps The end pressing levers 110a, 110b, and 110c simultaneously press the sheet bundle SB (step S106). In this state, binding processing is performed by the end surface binding stapler S1 (step S107), the rear end pressing levers 110a, 110b, and 110c are retracted (retracted) (step S108), and the sheet bundle SB is lifted upward by the discharge claw 52a to end the end surface. It is conveyed (released) out of the binding processing tray F (step S109).

  In the curl amount determination in step S105, if the curl amount M is greater than or equal to the specified value (step S105: NO), it is determined whether the binding mode is one-point binding or two-point binding (step S110). In this determination, when the binding is performed at one place, the trailing edge pressing lever (the first trailing edge pressing lever 11a positioned at the center in the example of FIG. 6) that is not positioned on the sheet binding side is the sheet first. The bundle SB is pressed. Next, the trailing edge pressing lever (the third trailing edge pressing lever 110c in the example of FIG. 6) disposed on the side positioned on the sheet binding side presses the sheet bundle SB, and the stapling process is executed in step S107. In this embodiment, the second rear end pressing lever 110b does not operate. Thereafter, the processes of steps S108 and S109 are executed, and the process is terminated.

  On the other hand, if it is determined in step S110 that the two-point binding is performed, first, the first rear end pressing lever 110a located at the center presses the center of the sheet bundle SB. Thereafter, the second and third rear end pressing levers 110b and 110c positioned on both ends respectively press the end of the sheet bundle SB, and the stapling process is executed in step S107. Thereafter, the processes of steps S108 and S109 are executed, and the process is terminated.

Thus, in this embodiment,
1) At least two rear end holding levers 110a, 110b, and 110c (three in the embodiment) are provided in the main scanning direction, the pressing means far from the binding position is operated first, and then the pressing means on the near side. Therefore, curling of the end portion of the sheet bundle SB is corrected, and swelling of the sheet or the sheet bundle SB between the adjacent rear end pressing levers 110a, 110b, 110c can be suppressed. Then, since the binding process is executed in a state in which the swelling is suppressed, the relative positional relationship between the end portion of the sheet bundle SB and the end surface binding stapler S1 is stabilized. As a result, the binding position is stabilized, and a binding process with high sheet alignment accuracy is possible.
2) At that time, one or both of the binding-side rear-end pressing levers 110b and 110c are operated with the rear-end pressing lever 110a in the center in the direction orthogonal to the sheet conveying direction of the sheet bundle first. In the latter case, for example, one is operated in one-point binding, and both are operated in two-point binding. Thereby, the bulge of the sheet | seat between the adjacent rear end holding levers 110a, 110b, and 110c or sheet bundle SB can be suppressed.
3) First to third rear end pressing levers 110a, 110b, based on the curl amounts detected by the curl amount detection sensors Se1, Se2 that detect the curl amount of the sheet bundle stacked on the end surface binding processing tray F. When the detected curl amount is smaller than the preset curl amount, these are simultaneously operated. When the curl amount is equal to or greater than the preset curl amount, the operation order of 110c is set. Since the rear end pressing lever is operated first and the closer side is operated later, it is possible to suppress the swelling of the sheet or the sheet bundle SB between the adjacent rear end pressing levers 110a, 110b, and 110c.
4) Since a rotatable rotating member is provided in the contact portion with the sheet bundle at the leading end of the trailing edge pressing levers 110a, 110b, 110c, the trailing edge pressing lever can be used when the swelling of the sheet is eliminated. 110a, 110b, and 110c do not hinder the bulge eliminating operation. This prevents press marks and wrinkles from occurring on the sheet surface.
5) Since the pressing order of the rear end pressing levers 110a, 110b, and 110c is changed according to the binding mode such as one-point binding and two-point binding, it is possible to select the pressing order suitable for the binding mode.
There are effects such as.

  The present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the gist of the present invention, and all technical matters included in the technical idea described in the claims are included. The subject of the present invention. The above embodiment shows a preferable example, but those skilled in the art can realize various alternatives, modifications, variations, and improvements from the contents disclosed in this specification, These are included in the technical scope described in the appended claims.

  Further, in the present embodiment, the sheet storage means in the claims is the end face binding processing tray F, the alignment means is the rear end reference fences 51, 51a, 51b and the hitting roller 12, and the binding means is the end face binding stapler S1. The sheet bundle is denoted by reference numeral SB, the pressing means is applied to the rear end pressing levers 110, 110a, 110b, and 110c, the pressing control means is applied to the CPU_PD1 of the sheet post-processing apparatus PD, and the central pressing means is the first rear end pressing lever 110a. The binding side pressing means is the second and third rear end pressing levers 110b and 110c, the detecting means is the curl amount detection sensors Se1 and Se2, the rotating member is the rollers 110a1, 110b1 and 110c1, and the sheet processing apparatus is In the sheet post-processing apparatus PD, the image forming system includes a sheet post-processing apparatus PD and an image forming apparatus PR. Corresponding, respectively.

  Further, the process or procedure for storing sheets is the process of step S101, the matching process and procedure is the process of step S102, the pressing process and procedure is the process of steps S106, S111, and S112, and the binding process and procedure is the step. In the process of S107, the process or procedure of operating the pressing means on the side far from the binding position and the process or procedure of operating the pressing means on the near side thereafter are combined into the process of step S111 or the process of step S112. Correspond.

12 Tapping roller 51, 51a, 51b Rear end reference fence 110, 110a, 110b, 110c Rear end holding lever 110a1, 110b1, 110c1 Roll F End surface binding processing tray F
PD sheet post-processing device PD1 CPU of sheet post-processing device
PR image forming apparatus S1 edge-binding stapler SB sheet bundle Se1, Se2 curl amount detection sensor

JP 2002-321868 A

Claims (9)

Sheet accommodating means for accommodating the sheet;
A rear end portion in the transport direction of the sheet stored on the sheet storage means, and an alignment unit that aligns the transport direction of the sheet;
At least two pressing means provided in the main scanning direction for pressing the sheet bundle aligned on the sheet storage means by the alignment means;
Binding means for binding the sheet bundle pressed by the pressing means;
The pressing means is a sheet processing apparatus,
A sheet processing apparatus comprising: a pressing control unit that first operates the pressing unit far from the binding position among the pressing units, and then operates the pressing unit on the near side. The sheet processing apparatus according to claim 1,
The sheet processing apparatus according to claim 1, wherein the pressing control unit operates the pressing unit at the center in the direction orthogonal to the sheet conveying direction of the sheet bundle first and the pressing unit on the binding side later. The sheet processing apparatus according to claim 1 or 2,
A detecting means for detecting a curl amount of the sheet bundle stacked on the sheet storing means;
The sheet processing apparatus, wherein the pressing control unit sets an operation order of the pressing unit based on a curl amount detected by the detecting unit. The sheet processing apparatus according to claim 3,
The pressing control means simultaneously operates the pressing means when the detected curl amount is smaller than a preset curl amount, and binds when the detected curl amount is equal to or greater than the preset curl amount. A sheet processing apparatus, wherein the pressing means on the side far from the position is operated first, and the near side is operated later. The sheet processing apparatus according to any one of claims 1 to 4,
The sheet pressing apparatus, wherein the pressing means includes a rotatable member that is rotatable at a contact portion of the sheet bundle. The sheet processing apparatus according to any one of claims 1 to 5,
The sheet pressing apparatus according to claim 1, wherein the pressing control means changes a pressing order of the pressing means according to a binding mode.   An image forming system comprising the sheet processing apparatus according to claim 1. Storing the sheet in the sheet storing means;
A step of abutting the rear end portion in the conveyance direction of the sheet accommodated in the accommodating step on the aligning means, and aligning the conveyance direction of the sheet;
Pressing the sheet bundle on the sheet storing means aligned in the aligning step by pressing means provided in at least two in the main scanning direction; and
Binding the sheet bundle pressed in the pressing step by binding means;
A sheet processing method comprising:
Of the at least two pressing means, the pressing step includes a step of operating the pressing means far from the binding position first, and a step of operating the pressing means on the near side thereafter. Sheet processing method. A procedure for storing the sheet in the sheet storing means;
A procedure for abutting the rear end portion in the conveying direction of the sheet stored in accordance with the storing procedure against the aligning means, and aligning the conveying direction of the sheet,
A procedure of pressing at least two sheet bundles on the sheet storage means aligned according to the alignment procedure in the main scanning direction;
Binding the sheet bundle pressed according to the pressing procedure by the binding means;
A sheet processing control program for causing a computer to execute sheet processing control according to the procedure,
The pressing step includes a step of operating the pressing unit far from the binding position among the at least two pressing units, and a step of operating the pressing unit on the near side thereafter. Characteristic sheet processing control program.