JP2006219302A - Paper processing system and image forming system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a paper processing system capable of accurately folding the center, while compactly and inexpensively folding the center. <P>SOLUTION: A paper carrying directional rear end part and the direction orthogonal to the paper carrying direction are registered, and the required number of partial paper is gripped in bundle carrying rollers 13a and 13b from a registered state, and a rear end fence 27 retreats, and carries a paper bundle in the folding plate 19 direction (downward). The paper bundle is stopped in the center of the length in the carrying direction of the paper bundle being a binding position by a staple unit 5, and is saddle-stitched. The saddle-stitched paper bundle is carried further downward, and is carried further until the binding position abuts on a position of the folding plate 19 after being positioned by abutting on a stopper 21. The paper bundle is stopped in the position, and is pushed in a folding roller 20 by a nip by projecting a folding plate 10, and is folded in two in the binding position. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention is provided integrally or separately in an image forming apparatus such as a copying machine, a printer, or a printing machine, and performs predetermined processing, such as sorting, stacking, binding, and saddle stitching, on an image-formed sheet (recording medium). The present invention relates to a sheet processing apparatus that performs bookbinding and discharges paper, and an image forming system including the sheet processing apparatus and the image forming apparatus.

  In recent years, in image forming apparatuses such as copying, faxing, and printers, there has been an increasing demand for post-processing on documents output from them, and in stapling processing, in addition to end binding that binds a predetermined number of sheets along one edge. Thus, there is an increasing demand for saddle stitching at a plurality of locations (generally, two locations) at predetermined intervals along a center line that bisects the paper. In addition, conventionally, functions such as saddle stitching and folding in relatively high-speed machines have been required for low-speed machines, and there is an increasing need to provide them at a lower price and space saving. In recent years, in image forming apparatuses such as a copy / fax / printer, there is an increasing demand for post-processing on documents output from them, and a predetermined number of sheets are bound along one edge in stapling.

  Therefore, for example, in Japanese Patent Application Laid-Open No. 10-250909, as means for carrying out end face binding and saddle stitching, conveyance rollers that can be pressed and separated are provided before and after the stapler, and the conveyance rollers are pressed and separated, and the separation operation and conveyance are performed. An invention is disclosed in which the sheet bundle is transported to the staple position by combining.

  Similarly, in Japanese Patent Laid-Open No. 2001-72328, conveyance rollers that can be pressed and separated in front and rear are provided before and after the stapler, and by combining the conveyance rollers with pressure and separation operations and conveyance, the bundle of sheets up to the staple position can be obtained. An invention is disclosed in which conveyance is performed, and further, a folding unit is provided on the downstream side to carry the sheet to the folding position.

Further, in Japanese Patent Laid-Open No. 11-193162, a stapling and folding means is provided by providing a leading end stopper for regulating the leading end of the sheet as a saddle stitching and folding positioning method, and moving the leading end stopper back and forth along the transport path. An invention is disclosed in which the saddle stitching and folding are performed by moving to the position.
JP-A-10-250909 Japanese Patent Laid-Open No. 11-193162 JP 2001-72328 A

  However, in the invention disclosed in Japanese Patent Laid-Open No. 10-250909, the conveyance is performed via the two conveyance rollers, and in order to ensure the conveyance quality (feeding accuracy and bundle misalignment accuracy) (conveying roller) It is difficult to ensure accuracy when switching between transports), the control (pressure contact / separation, transport timing) of the two transport rollers is complicated, and a sensor for detecting the edge of the paper must be provided near each transport roller. There are drawbacks such as complicated construction and operation.

  Further, in the invention disclosed in Japanese Patent Application Laid-Open No. 2001-72328, the paper always passes through the conveyance roller before reaching the folding portion, and there is a possibility that wrinkles are generated in the binding portion due to squeezing by the conveyance roller. In addition, since the conveyance distance becomes long, the folding position accuracy tends to vary easily.

  Further, in the invention disclosed in Japanese Patent Application Laid-Open No. 11-193162, the binding position and the folding position of the sheet bundle are always determined with reference to the leading end, and the positional relationship between the two varies due to the curled state or the bending of the sheet. It is easy and it cannot be denied that it is difficult to ensure accuracy. Thus, in order to ensure the accuracy, a sheet presser or the like for limiting the position of the sheet between the guide plates can be added, but there are drawbacks such as a complicated mechanism. Further, the leading end stopper has a drawback that the mechanism must secure a moving amount corresponding to the maximum size of the paper, and the machine becomes large (long in the transport direction).

  The present invention has been made in view of the actual situation of the prior arts, and the object thereof is to solve the problems of the prior arts described above, so that the middle folding can be realized compactly and at low cost, and the middle folding can be performed with high accuracy. It is an object of the present invention to provide a sheet processing apparatus and an image forming system that can perform the above processing.

  In order to achieve the above object, the first means includes a stacking means for stacking sheets and a stacking means stacked in the stacking means in a sheet processing apparatus having processing means for performing predetermined processing on the sheets after image formation. A first alignment unit that aligns the sheet bundle, a first conveyance unit that conveys the sheet bundle aligned by the first alignment unit, and a sheet bundle conveyed by the first conveyance unit near the folding position. A second aligning means for aligning the sheet bundle, a second conveying means for conveying the sheet bundle aligned by the second aligning means to the folding position, and a folding means for folding the sheet bundle at the folding position, The first transport unit is located upstream of the position of the first alignment unit in the paper transport direction.

  The second means is a paper processing apparatus having a processing means for performing a predetermined process on the paper after the image formation, and the first means for aligning the stack means for stacking the paper and the paper bundle stacked on the stack means. The first aligning unit, the first conveying unit that conveys the sheet bundle aligned by the first aligning unit, the binding unit that performs the binding process on the sheet bundle, and the first binding unit. A second aligning unit that aligns the sheet bundle conveyed by the conveying unit in the vicinity of the folding position, a second conveying unit that conveys the sheet bundle aligned by the second aligning unit to the folding position, and A folding means for folding the sheet bundle at the folding position, wherein the first conveying means is located upstream of the position of the first aligning means in the paper conveying direction.

  The third means is characterized in that, in the first or second means, the first conveying means conveys the end of the sheet bundle on the downstream side in the conveying direction until it abuts against the stover.

  The fourth means is characterized in that an image forming system is constituted by the sheet processing apparatus according to the first to third means and the image forming apparatus provided integrally or separately with the sheet processing apparatus.

  As described above, according to the present invention, it is possible to realize folding in a compact and low-cost manner with high accuracy and only by setting the conveyance timing and setting position of the sheet bundle by the first and second conveyance means. Therefore, it is possible to provide a sheet processing apparatus and an image forming system that can be used.

Hereinafter, the best mode for carrying out the present invention will be described with reference to the drawings.

  FIG. 1 is a diagram showing a schematic configuration of a sheet post-processing apparatus according to an embodiment of the present invention, and FIGS. 2 and 3 are diagrams showing a schematic configuration of an image forming system including the sheet post-processing apparatus shown in FIG. . The form shown in FIG. 2 shows an outline of a system as a copying machine, and includes an image forming apparatus PR, a paper feeding apparatus PF that supplies paper to the image forming apparatus, a scanner SC for reading an image, and a circulating automatic document. It consists of a feeding device ARDF. The sheet on which the image is formed by the image forming apparatus PR is conveyed to the entrance guide plate of the finisher FR via the relay unit CU. FIG. 3 is a schematic diagram of a printer-type system without the scanner SC and the circulation type automatic document feeder ARDF, and other configurations are the same as those of the copying machine. The sheet post-processing device indicated as the finisher FR is attached to the side portion of the image forming apparatus PR as described above, and the paper discharged from the image forming apparatus PR is guided to the paper post-processing device FR, and the rear of the paper Various post-processing are performed by the function of the processing device FR. The image forming apparatus PR may be any apparatus having a known image forming function, such as an apparatus for an electrophotographic image forming process or an apparatus having an inkjet print head. .

  In a sheet post-processing apparatus FR (hereinafter referred to as reference numeral 2) as a sheet processing apparatus, a sheet received from the image forming apparatus PR as illustrated in FIG. 1 is a post-processing unit that performs post-processing on one sheet. (In the embodiment, it passes through an entrance conveyance path A having a punch unit 3 as a punching means), to an upper conveyance path B that leads to a proof tray 18, an intermediate conveyance path C that leads to a shift roller 9, and a staple tray 10 that performs alignment and stapling. The lower conveyance path D is guided by the branching claw 24, the turn guide 36, the branching claw 25, and the turn guide 37. The paper transported onto the staple tray 10 by the transport rollers 33, 34, and 35 is aligned on the staple tray 10 in a direction perpendicular to the paper transport direction by the jogger fence 12. It is matched to the standard. Thereafter, in the case of end face binding, a stapling process is performed at a predetermined position, the paper is conveyed upward by the discharge claw 11, and is discharged and stacked on the paper discharge tray 17 by the discharge roller 15. FIG. 8 shows an outline of the drive portion of the discharge claw 11. A drive shaft 103 is connected to the timing pulley 101 on the drive side of the timing pulleys 101 and 102 around which the discharge belt 14 is wound. The driving force is obtained from the stepping motor 106 through the gear trains 104 and 105 provided on the drive shaft.

  On the other hand, in the case of saddle stitching, after the sheet bundle is aligned, the bundle is transported downward by the bundle transport roller pair 13a and 13b, and the binding process is performed at the saddle stitching position. When the saddle stitching process is completed, the bundle conveying rollers 26a and 26b carry the sheet to the folding position, the folding plate 19 and the folding roller pair 20 perform the middle folding process, and the middle folding discharge roller 22 performs the middle folding discharge. The paper is discharged onto the paper tray 23 and stacked.

  A common inlet conveyance path A upstream of the upper conveyance path B, intermediate conveyance path C, and lower conveyance path D has an inlet sensor 301 that detects a sheet received from the image forming apparatus PR, and a conveyance roller 31 downstream thereof. The punching unit 3 and the branching claw 24 and the turn guide 36 are sequentially arranged downstream thereof.

  The branching claw 24 is held in the state of the solid line in FIG. 1 by a spring (not shown). When the solenoid (not shown) is turned on, the branching claw 24 is rotated counterclockwise in the figure (in the state of the one-dot chain line). If the solenoid is OFF, the paper is distributed to the upper conveyance path B. The branching claw 25 is held in a solid line state in FIG. 1 by a spring (not shown). When the solenoid (not shown) is turned on, the branching claw 25 is rotated clockwise (in a one-dot chain line state), and the sheet is fed to the intermediate conveyance path C. Distribute. If the solenoid is OFF, the sheet is sent to the lower conveyance path D as it is and conveyed by the conveyance rollers 33 and 34. The turn guides 36 and 37 have a function of helping to sort the paper by the branch claws 24 and 25, respectively. The turn guides 36 and 37 have a function of reducing the sheet conveyance resistance at the small-diameter branching portion by being rotated by the sheet bent in the conveyance direction by the branch claws 24 and 25.

  The intermediate transport path C is provided with a shift roller 9 that can move the paper by a fixed amount in a direction perpendicular to the transport direction. The shift roller 9 exhibits a shift function by being moved in a direction perpendicular to the transport direction by a driving means (not shown). The sheet sent to the intermediate conveyance path C through the conveyance roller 32 and the turn roller 37 moves by a certain amount in the direction perpendicular to the conveyance direction while being conveyed by the shift roller 9, so that the sheet becomes a certain amount in the direction perpendicular to the conveyance direction. In this state, the paper is discharged by the discharge roller 15 and stacked on the paper discharge tray 17. The timing is determined based on paper detection information of the roller shift sensor 303, paper size information, and the like.

  A staple tray discharge sensor 305 is provided in the lower transport path D, and serves as a trigger for the alignment operation when the paper is present in the transport path and the paper is discharged to the staple tray 10. The sheets sent to the conveyance path D are sequentially conveyed by the conveyance rollers 33, 34, and 35 and are aligned after being stacked on the staple tray 10.

  The trailing edge of the sheet discharged to the staple tray 10 is aligned with reference to the trailing edge fence 27 as the first sheet bundle regulating means. The rear end fence 27 is configured to be rotatable about the central axis of the bundle conveying roller 13a as shown in FIG. 12, and the solenoid side of the rear end fence 27 is operated by a solenoid 70 as a first restriction release means. The end portion 27a is driven, and the tip portion is retracted from the conveyance path. Thereby, it is comprised so that conveyance of a sheet bundle may not be prevented.

  The sheets stacked on the staple tray 10 are dropped down by the hitting roller 8 at any time and the lower ends are aligned. As shown in FIG. 4, which is a perspective view showing the mechanism around the staple tray 10 with the fulcrum 8a as the center, the tapping roller 8 is given a pendulum motion by the tapping solenoid 8s and intermittently applied to the paper fed into the staple tray 10. Acting on the rear end fence 27. The hitting roller 8 is rotated counterclockwise by the timing belt 8t in a direction in which the paper is moved to the trailing edge fence 27. Alignment in the direction perpendicular to the conveyance direction of the sheets stacked on the staple tray 10 is performed by a jogger fence 12 as an alignment member. The jogger fence 12 is driven via a timing belt 12b by a jogger motor 12m capable of forward / reverse rotation shown in FIG. 4, and reciprocates in a direction perpendicular to the paper transport direction. By performing an operation of pressing the end face of the paper by this movement, the paper is aligned at right angles to the transport direction. This operation is performed at any time during loading of sheets and after loading of the final sheet. A sensor 306 provided in the staple tray 10 is a so-called paper detection sensor that detects the presence or absence of paper on the staple tray 10. The tapping roller 8, the rear end fence 27, and the jogger fence 12 constitute first alignment means for aligning the sheet bundle in a direction orthogonal to a direction parallel to the sheet conveyance direction.

  The bundle conveying rollers 13a, 13b and 26a, 26b can be pressurized and released by the mechanism shown in FIG. 11, and after passing the sheet bundle in the released state, pressurize and convey the sheet bundle. . The bundle conveying rollers 13a, 13b and 26a, 26b can be freely pressed and separated by a pressure release motor 63. The transport rollers 13a, 13b and 26a, 26b are rotationally driven by a stepping motor 50. By controlling the number of rotations of the stepping motor 50, the transport amount of the sheet bundle is controlled. Each of the bundle conveying rollers 13a, 13b and 26a, 26b can be independently pressed and moved apart. Since the bundle conveying roller pressure releasing mechanisms as the first and second pressure contact force releasing means are the same, the bundle conveying rollers 13a and 13b will be described in detail.

  As shown in FIG. 11, the bundle transport rollers 13a and 13b are connected to a drive system so that the rotation directions are opposite and rotate at the same speed. The drive is transmitted to a timing pulley 53 and a gear pulley 54 that are arranged coaxially with the bundle conveying roller 13a using the stepping motor 50 as a drive source. Further, driving is transmitted from the gear pulley 54 to the timing pulley 58 disposed coaxially with the bundle conveying roller 13b via the arm 56 via the idler pulley 55, and the bundle conveying roller 13b rotates. The arm 56 is rotatable about the gear pulley 55 and acts in a direction in which the arm 56 is pressed against the sheet by a tension spring 64 provided on the shaft of the bundle conveying roller 13b. Further, a link 59 is connected to the shaft of the bundle conveying roller 13b, and a long hole 59a is provided on the other side of the link, so that it can freely rotate on a convex portion 60p provided on the circumference of the gear 60. It is fitted. Further, a sensor 61 is provided at one end of the gear 60 for detecting the opened state of the bundle conveying rollers 13a and 13b by the filler 60a. By rotating the stepping motor 63 counterclockwise and clockwise, Release pressure. FIG. 11A shows a pressure release state, and FIG. 11B shows a pressure contact state.

  The staple unit 5 includes a stitcher unit 5a that strikes the needle and a clincher unit 5b that bends the tip of the needle that is driven into the sheet bundle. In the staple unit 5 in the present embodiment, the stitcher 5a and the clincher 5b are configured separately, and can be moved in a direction perpendicular to the sheet bundle conveying direction by the stapler moving guide 6, and the stitcher 5a and the clincher 5b are not shown. A relative positioning mechanism and a moving mechanism are provided. The stapling position in the conveyance direction of the sheet bundle is performed by conveying the sheet bundle by the bundle conveyance rollers 13a and 13b. Thus, stapling can be performed at various positions of the sheet bundle.

  The middle folding mechanism portion is located downstream of the staple unit 5 in the sheet conveyance direction (downstream side when folding the sheet, and lower side in position). This is composed of a pair of folding rollers 20, a folding plate 19, a stopper 21, and the like until the sheet bundle stapled at the center in the sheet conveying direction in the upstream staple unit 5 hits the stopper 21 by the bundle conveying rollers 13a and 13b. By conveying and temporarily releasing the nip pressure of the bundle conveying roller 13b, the position of the folding reference position of the sheet bundle is determined. Thereafter, the nip pressure of the bundle conveying rollers 26a and 26b is applied to hold the sheet bundle, the stopper 21 moves backward and comes off from the rear end of the sheet bundle, and the necessary distance is determined by the sheet size signal sent from the image forming apparatus main body. It is conveyed and the folding position is put out. The sheet bundle conveyed to the folding position (usually the center in the sheet bundle conveying direction) is pushed into the nip of the pair of folding rollers 20 by the folding plate 19, and the pair of folding rollers 20 presses and rotates the sheet bundle. It is folded more than that. At this time, if the paper size is large, the paper bundle is sent downstream of the stopper 21 in the paper transport direction. Therefore, in this embodiment, the end of the sheet bundle is guided in the horizontal direction by curving the conveyance path downstream from the position where the stopper 21 is disposed. With this configuration, it is possible to transport a sheet even if it has a large sheet size, and the size in the height direction of the sheet post-processing device 2 can be made compact.

  As shown in FIG. 13, the stopper 21 as the second sheet bundle restricting means, which is the second aligning means, is configured to be rotatable around the central axis of the bundle conveying roller 26a. The solenoid-side end portion 21a is driven by a solenoid 72 serving as a restriction release means, and the tip end portion is retracted from the conveyance path. The folded sheet bundle is discharged and stacked on the half-fold discharge tray 23 by the half-fold discharge roller 22. The sensors 310 and 311 at the folded portion detect the presence or absence of paper. In addition, the sensor 313 of the half-folded paper discharge tray 23 detects the presence or absence of a paper bundle on the middle-folded paper discharge tray 23, and counts the number of paper bundles discharged from the state where there is no paper bundle. This is used to detect the fullness of the paper discharge tray 23 in a pseudo manner. The folding end stopper position detection sensor 312 detects the operation of the stopper 21 and the end position of the sheet bundle when the stopper is released.

  FIG. 14 shows the control circuit of the sheet post-processing apparatus according to the present embodiment together with the image forming apparatus. The control apparatus 350 is composed of a microcomputer having a CPU 360, an I / O interface 370, etc., and the main body of the image forming apparatus PR. Each switch of the control panel, etc., inlet sensor 301, upper paper discharge sensor 302, roller shift sensor 303, staple paper discharge sensor 305, staple tray paper presence sensor 306, discharge claw position detection sensor 307, paper discharge sensor 308, paper surface detection Signals from sensors such as the sensor 309, the folding unit paper presence / absence detection sensor 310, the folding roller arrangement detection sensor 311, the folding end stopper position detection sensor 312, and the paper presence / absence detection sensor 313 are input to the CPU 360 via the I / O interface 370. Is done. The CPU 360 controls various motors and solenoids based on the input signal. The punch unit 3 also performs punching according to the instruction of the CPU 360 by controlling the clutch and the motor.

  The sheet post-processing device 2 is controlled by the CPU 360 executing a program written in a ROM (not shown) while using a RAM (not shown) as a work area.

Hereinafter, an actual post-processing operation will be described using a specific post-processing mode as an example. (1) No-processing mode (proof discharge)
The paper output from the image forming apparatus 1 passes through the entrance conveyance path A, is guided to the upper conveyance path B by the first branching claw 24, is punched if necessary, and is discharged to the proof tray 18 by the paper discharge roller 7. The paper is ejected.

(2) Shift stacking mode Even when a bundle of sheets is output in units of copies, when stapling is not performed, the stacks are shifted and stacked for each unit, making it easy to understand the determination of the units. In this mode, the paper output from the image forming apparatus 1 passes through the entrance conveyance path A and is guided in the lower conveyance path D direction by the first branching claw 24. At this time, a punch hole is made at the end of the sheet by the punch unit 3 according to the user's selection. Thereafter, the sheet is guided to the intermediate conveyance path C by the second branch claw 25, conveyed while being shifted in the direction perpendicular to the conveyance direction by the shift roller 9, guided to the sheet discharge guide plate 16, and discharged to the sheet discharge tray 17 by the discharge roller 15. The paper is discharged and stacked. The punch residue after the punch hole is opened by the punch unit 3 is accommodated in the hopper 4.

(3) End surface binding mode The end surface binding mode is a mode in which staple binding is performed on the end surface of the sheet bundle in units of copies. FIG. 15 is a flowchart showing an operation procedure in the end face binding mode.

  The paper output from the image forming apparatus passes through the entrance conveyance path A and is guided in the lower conveyance path D direction by turning on the first branching claw 24 (step S101), and drives each conveyance roller and the discharge roller 35. (Steps S102 and S103) and move along the transport path D. At this time, the stacking number counter that counts the sheets stacked on the staple tray 10 is cleared (step S104), and a punch hole is opened at the end of the sheet by the punch unit 3 according to the user's selection (step S105). Thereafter, the sheet is stacked on the staple tray 10 through the lower conveyance path D as it is. The sheets discharged to the staple tray 10 are aligned by the tapping roller 8 with the trailing edge fence 27 as a reference (sheet bundle is position in FIG. 4-steps S106 and S107).

  The alignment in the direction perpendicular to the transport direction of the sheet bundle is performed by the operation of narrowing the width of the sheet stacking portion of the staple tray 10 by the jogger fence 12 (position of the sheet bundle in FIG. 4-step S108). When the aligning operation is completed, the stacking number counter is counted up (step S109), and after the necessary number of sheets are stacked on the staple tray 10 (step S110), the bundle conveying rollers 13a and 13b hold the lower end of the sheet bundle. Then, the sheet is held (step S111), and the trailing edge fence 27 is retracted from the sheet stacking surface (step S112).

  The sheet bundle is stapled at the binding position by the staple unit 5 (normal edge binding is 5 mm in the sheet conveyance direction) (step S113). The stapler binding position in the end binding mode can be mainly selected from the front, two locations, and the back. The stitcher 5a and the clincher 5b are positioned relative to each other by the stapler moving guide 6 according to the selected binding position. The stapler binding is performed by moving in the direction perpendicular to the sheet conveying direction while maintaining the above. The staple unit 5 is divided into a stitcher 5a for punching a needle and a clincher 5b for performing a process of bending a needle penetrating the sheet bundle, and the sheet can pass between the stitcher 5a and the clincher 5b. It is a feature.

  When the end face binding is thus completed, the discharge claw 11 moves in the paper discharge direction (step S114), and simultaneously with the end of the paper, the pressure contact state of the bundle conveying rollers 13a and 13b is released (step S115). When the binding process is completed, the paper discharge guide plate 16 is opened by a predetermined angle (step S116), and the bound sheet bundle is lifted upward by the discharge claw 11 that moves together with the discharge belt 14. The discharge claw 11 can lift the sheet bundle to the upper end of the staple tray 10 by the discharge belt 14. When the sheet bundle enters between the sheet discharge guide plates 16, the sheet discharge guide plate 16 is closed, and the sheet bundle is discharged from the discharge roller 15. (Step S117), the sheet is discharged and stacked on the discharge tray 17 (step S118). The discharge guide plate 16 can be adjusted with respect to the discharge roller according to the thickness of the sheet bundle.

  When the paper discharge is completed, the discharge roller 15 is stopped (step S119), and the discharge belt 14 is driven until the discharge position detection sensor is turned on, that is, until the discharge claw 11 is located at the home position (step S120). Stop when the position is reached (step S121). This operation is repeated from step S104 until the predetermined number of copies is completed.

  The end face binding operation is shown in FIG. In FIG. 9A, the rear end portion in the sheet conveyance direction and the direction orthogonal to the sheet conveyance direction are aligned (steps S107 and S108), and the required number of sheets of one sheet is aligned (step S110). From this state, as shown in FIG. 9 [b], it is picked up by the bundle conveying rollers 13a and 13b (step S111), and the rear end fence 27 is moved backward as shown in FIG. 9 [c] (step S112). 5 moves to the binding position, and the binding operation is performed at the binding position as shown in FIG. 9R> 9 [d] (step S113).

(4) Saddle Stitching Mode The saddle stitching mode is a mode in which staple binding is performed at the center of the sheet bundle. FIG. 16 is a flowchart showing an operation procedure in the saddle stitching mode. In the following description, the same reference numerals are assigned to operations equivalent to those in the end face binding mode. In this saddle stitch binding mode, steps S101 to S112 and steps S114 to S121 are the same as in the end face binding mode, and thus description thereof will be omitted, and only different points will be described.

  In step S101, the first branch claw 24 is turned on to guide in the lower conveyance path D direction. In step S111, the bundle conveyance rollers 13a and 13b hold the lower end of the sheet bundle, and in step S112, the rear end fence 27 is moved to the sheet stacking surface. The bundle transport rollers 13a and 13b further transport the sheet bundle downward (step S121). The sheet bundle is stopped at the binding position by the staple unit 5 (at the center of the length in the conveyance direction of the sheet bundle during saddle stitching) (steps S122 and S123), and stapled by the staple unit 5 (step S124).

  In the saddle stitching mode, the stapler usually has two binding positions. According to the binding position, the stitcher 5a and the clincher 5b are moved by the stapler moving guide 6 in a direction perpendicular to the sheet conveying direction while maintaining the relative position of each other. Then staple the stapler. The bundle of sheets for which the binding process has been completed is conveyed upward by the bundle conveying rollers 13a and 13b (step S125), and when returned to the sheet bundle alignment position (step S126), the bundle conveying rollers 13a and 13b are stopped (step S127). ), The paper is discharged upward by the discharge claw 11 (step S114). And the process after step S115 is performed.

(5) Saddle-stitch bookbinding mode The saddle-stitch bookbinding mode is a mode for performing simple bookbinding like a so-called weekly magazine by stapling the center of a sheet bundle and folding it in the middle. FIG. 17 is a flowchart showing an operation procedure in the saddle stitch binding mode. In the following description, the same reference numerals are assigned to operations equivalent to those in the end face binding mode. In this saddle stitch binding mode, steps S101 to S112 are the same as in the end face binding mode, and thus description thereof will be omitted, and only different points will be described.

  In step S101, the first branch claw 24 is turned on to guide in the lower conveyance path D direction. In step S111, the bundle conveyance rollers 13a and 13b hold the lower end of the sheet bundle, and in step S112, the rear end fence 27 is moved to the sheet stacking surface. The bundle transport rollers 13a and 13b transport the sheet bundle downward (step S131). The sheet bundle is stopped at the binding position by the staple unit 5 (at the center of the conveyance direction length of the sheet bundle during saddle stitching) (steps S132 and S133), and stapled by the staple unit 5 (step S134).

  In the saddle stitching mode, the stapler usually has two binding positions. According to the binding position, the stitcher 5a and the clincher 5b are moved by the stapler moving guide 6 in a direction perpendicular to the sheet conveying direction while maintaining the relative position of each other. Then staple the stapler.

  The sheet bundle is once positioned by abutting the rear end position by the stopper 21 (steps S135 and S136), and the center of the sheet bundle in the conveyance direction is again placed on the folding plate 19 by the bundle conveyance rollers 26a and 26b. It is sent to the contact position (step S137-step S143). Thereafter, the folding plate 19 pushes the sheet bundle toward the nip of the middle folding roller pair 20 (steps S144 and S145), and the sheet bundle is pressurized between the nips by the force of a spring (not shown) applied to the middle folding roller pair 20. (Step S146) Folded in half, and discharged and stacked on the half-folded paper discharge tray 23 by the half-fold paper discharge roller 22 immediately after (Step S147). Then, the center folding roller 20 is stopped (step S148), and the rear end fence 27 is returned to the aligned position (step S149). This operation is repeated from step S104 until the predetermined number of copies is completed.

  The operation of saddle stitching is shown in FIG. In FIG. 10A, the rear end portion in the sheet conveyance direction and the direction orthogonal to the sheet conveyance direction are aligned (steps S107 and S108), and the required number of sheets of one sheet is aligned (step S110). From this state, as shown in FIG. 10B, the sheet is caught by the bundle conveying rollers 13a and 13b (step S111), the rear end fence 27 is retracted (step S112), and the sheet bundle is moved toward the folding plate 19 (downward). Transport. Then, the sheet bundle is stopped at the center of the conveyance direction length of the sheet bundle, which is a binding position by the staple unit 5, and is saddle-stitched.

  The saddle-stitched sheet bundle is further conveyed downward as shown in FIG. 10C, positioned after being brought into contact with the stopper 21 (steps S135 and S136), and then the binding position is the position of the folding plate 19 (folding). It is further conveyed until it reaches (position). Then, as shown in FIG. 10D, the sheet bundle is stopped at the position, and the folding plate 10 is protruded and pushed into the nip into the folding roller 20 (steps S144 to S146). In this way, it can be folded in half at the binding position. If the front end of the folding plate 19 protrudes to contact the sheet bundle, the staple is brought into contact with the folding plate 19 when the folding position is reached, so that the position accuracy of the folding position can be ensured.

(6) No Binding / Folding Mode The no binding / middle folding mode is a mode in which folding processing is performed at the center without performing a binding operation on a sheet bundle. FIG. 18 is a flowchart showing an operation procedure in the no-binding / middle folding mode.

  This mode is equivalent to a mode in which the saddle stitching operation is deleted from the saddle stitch binding mode. Therefore, the processing from step S131 to step S134 in the saddle stitch binding mode shown in FIG. 17 is omitted, and after the trailing edge fence 27 is retracted from the paper placement surface in step S112, the sheet bundle is immediately transported downward. Once the rear end position is abutted and positioned by the stopper 21 (steps S135 and S136), the folding operation is performed (steps S137 to S149).

  Other operations that are not particularly described are the same as those in the saddle stitch binding mode.

  Here, the subroutines of punch control, hitting roller 8 control, staple unit 5 control and folding plate 9 control in each mode will be described.

  FIG. 19 is a flowchart showing the processing procedure of punch control in step S105. In this process, first, when the paper reaches the punch position (step S201), the presence / absence of a punch request is checked (step S202), and the punch is executed only when there is a punch request (step S203).

  FIG. 20 is a flowchart showing a processing procedure for hitting roller 8 control in step S107. In this process, first, when the paper reaches the strike position (step S301), the strike roller 8 is driven for a predetermined time to move the paper to the rear end fence 27 side (steps S302 and S303), and the operation is stopped (step S301). S304).

  FIG. 21 is a flowchart showing a processing procedure for controlling the staple unit 5 in steps S113, S124, and S134. In this process, first, the stapler unit 5 is moved to the binding position (step S401). When the stapler unit 5 is positioned at the designated binding position (step S402), the stapler unit 5 is stopped (step S403), and the stapling operation is performed. Is executed (step S404). When the stapling at the designated position is completed (step S405), the stapler unit 5 is retreated (step S406), and the stapler unit 5 is retracted (step S406).

  FIG. 22 is a flowchart showing the processing procedure of the folding plate 19 control in step S144. In this process, first, the folding plate 19 is moved in the nip direction of the folding roller 20 (step S501). When the leading end of the folding plate 19 reaches the nip position of the folding roller 20 (step S502), the folding plate 19 is moved. Is stopped (step S503) and the process is terminated.

  Here, since the staple is moved by the subroutine of the staple unit 5 control, the moving operation of the staple unit will be described.

  FIG. 5 is a diagram showing the position of the staple unit 5 before entering the binding operation. The staple unit 5 stands by at a position that does not contact the rear end fence 27 and that is closest to the next binding position. This position is indicated by a solid line or a two-dot chain line.

  FIG. 6 is a view showing the position of the staple unit 5 that is bound at two end faces. As described above, in the end face binding mode, the sheet bundle is stapled at the binding position by the staple unit 5 (normal end binding is 5 mm in the sheet conveying direction). The stapler binding position in the end binding mode can be mainly selected from the front, two locations, and the back. The stitcher 5a and the clincher 5b are positioned relative to each other by the stapler moving guide 6 according to the selected binding position. The stapler binding is performed by moving in a direction perpendicular to the sheet conveying direction while maintaining the above. At this time, in the case of the binding position where the staple unit 5 and the rear end fence 27 are in contact (small size binding at one place, binding at two places, saddle stitching), the rear end fence 27 moves backward from the sheet stacking surface, and then Then, the staple unit 5 moves in a direction perpendicular to the sheet conveying direction to perform stapler binding. This operation is the same in the case of saddle stitching shown in FIG. When the binding mode is two-point binding (end-face two-point binding and saddle stitching), the printer waits at a standby position opposite to the sheet conveyance direction for each bundle. This standby position is the position of the solid line and the two-dot chain line in FIG. 5, and these positions alternately become standby positions. Thereby, it is possible to move to the standby position at the shortest distance from the second binding operation.

  As described above, according to the present embodiment, the aligned sheet bundle is pressed between the bundle conveying rollers 13a and 13b as the first conveying means and the bundle conveying rollers 26a and 26b as the second conveying means. In addition, by releasing the pressure contact and setting the delivery and post-processing of the sheet bundle with good timing, it is possible to perform the binding operation and the middle folding operation on the sheet bundle with a simple configuration. That is, when binding by the stapler unit 5, the bundle conveyance rollers 13a and 13b hold the sheet bundle and convey the sheet bundle until it comes into contact with the stopper 21 as the second sheet bundle regulating means. The sheet is held by the bundle conveying rollers 26a and 26b, and the holding force of the bundle conveying rollers 13a and 13b is released, and the sheet bundle is conveyed by the bundle conveying rollers 13a and 13b, and is folded at the folding position. Can be done. For this reason, the bundle conveying rollers 13a and 13b and the bundle conveying rollers 26a and 26b need to be as close as possible so as to deliver a minimum size for folding in two, for example, the B5 vertical size, and the bundle conveying rollers 26a and 26b. On the further downstream side, a maximum size that can be folded in half, for example, a length that does not interfere with the conveyance path when the center portion of the A3 vertical sheet bundle is located at the folding position is required. By setting such a size relationship and the timing relationship, it is basically possible to cope with saddle stitching and center folding with only two pairs of conveying rollers.

  However, in order to align the sheet bundle and accurately set the position, the rear end fence 27 and the stopper 21 which are the first and second restricting means are required, and the operation timing and the installation position thereof are determined by the two transports. By setting between the roller pairs 13a, 13b, 26a, and 26b, it is possible to realize a compact sheet post-processing apparatus having a simple configuration having the function of half-folding and saddle stitching. Therefore, even if the paper processing apparatus has such a simple configuration, it can be folded accurately.

It is a figure which shows schematic structure of the paper post-processing apparatus which concerns on the Example of this invention. It is a figure which shows schematic structure of the image forming system (copier form) provided with the paper post-processing apparatus shown in FIG. It is a figure which shows schematic structure of the image forming system (printer form) provided with the paper post-processing apparatus shown in FIG. It is a perspective view which shows the mechanism around a staple tray. It is a figure which shows the position of the staple unit before entering into binding operation. It is a figure which shows the position of the staple unit of 2 end surface binding. It is a figure which shows the position of the staple unit of saddle stitching. It is a figure which shows the outline of the drive part of a discharge belt and a discharge nail | claw. It is a figure which shows operation | movement of an end surface binding. It is a figure which shows the operation | movement of saddle stitching. It is a figure which shows the contacting / separating mechanism and operation | movement of a bundle conveyance roller. It is a figure which shows the drive mechanism of a rear-end fence. It is a figure which shows the drive mechanism of a stopper. 2 is a block diagram illustrating a control circuit of the sheet post-processing apparatus according to the present embodiment together with the image forming apparatus. FIG. It is a flowchart which shows the process sequence of end surface binding mode. It is a flowchart which shows the process sequence of saddle stitching mode. It is a flowchart which shows the process sequence of saddle stitching and center folding mode. It is a flowchart which shows the process sequence of a bindingless / center folding mode. It is a flowchart which shows the process sequence of punch control. It is a flowchart which shows the process sequence of tapping roller control. It is a flowchart which shows the processing procedure of staple unit control. It is a flowchart which shows the process sequence of folding plate control.

Explanation of symbols

2 Paper Post-Processing Device 5 Staple Unit 8 Tapping Roller 10 Staple Tray 11 Release Claw 12 Jogger Fence 13a, 13b Bunch Conveying Roller 19 Folding Plate 20a, 20b Middle Folding Roller 21 Stopper 26a, 26b Bunch Conveying Roller 27 Rear End Fence 350 Control Device 360 CPU

Claims (4)

In a paper processing apparatus having processing means for performing predetermined processing on paper after image formation,
Stacking means for stacking paper,
First alignment means for aligning a stack of sheets stacked on the stack means;
First conveying means for conveying the sheet bundle aligned by the first alignment means;
Second alignment means for aligning the sheet bundle conveyed by the first conveyance means in the vicinity of the folding position;
Second conveying means for conveying the sheet bundle aligned by the second aligning means to the folding position;
Folding means for folding the sheet bundle at the folding position;
With
The sheet processing apparatus, wherein the first transport unit is located upstream of the position of the first alignment unit in the sheet transport direction. In a paper processing apparatus having processing means for performing predetermined processing on paper after image formation,
Stacking means for stacking paper,
First alignment means for aligning a stack of sheets stacked on the stack means;
First conveying means for conveying the sheet bundle aligned by the first alignment means;
Binding means for performing a binding process on a bundle of sheets;
A second aligning unit that aligns the sheet bundle bound by the binding unit and conveyed by the first conveying unit in the vicinity of the folding position;
Second conveying means for conveying the sheet bundle aligned by the second aligning means to the folding position;
Folding means for folding the sheet bundle at the folding position;
With
The sheet processing apparatus, wherein the first transport unit is located upstream of the position of the first alignment unit in the sheet transport direction.   3. The sheet processing apparatus according to claim 1, wherein the first conveying unit conveys the end of the sheet bundle downstream in the conveying direction until it abuts against the stover. A sheet processing apparatus according to any one of claims 1 to 3,
An image forming apparatus provided integrally with or separately from the sheet processing apparatus;
An image forming system comprising:

Images