JP2007230659A - Sheet post-processor and stacking method of sheet bundle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sheet post-processor capable of orderly storing a sheet bundle with excellent arranging performance when storing the sheet bundle. <P>SOLUTION: A stack means is provided with a sheet holding means for supporting the sheet bundle in a loading state. The sheet holding means has a shift means moving so as to be retreated according to a loading quantity of sheets and a sheet bundle thickness detecting means having its control means and detecting the thickness of the sheet. The control means is constituted so as to make a retreat moving distance of the sheet holding means different on the basis of thickness information from the sheet thickness detecting means. The stack means is provided with a paper face abutting regulating means for registering by abutting the uppermost sheet supported by the sheet holding means. The shift means moves to a carrying-in standby position separated by a predetermined quantity from a carrying-in port when the sheet holding means carries in the sheets, and moves so as to register by making the uppermost sheet abut against the paper face abutting regulating member after carrying in the sheets. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a sheet post-processing apparatus that binds sheets output from an image forming apparatus such as a copying machine or a printing machine in a bundle and binds the back with an adhesive or the like, and a sheet stacking method used for the same. In particular, the present invention relates to a stack mechanism and a method for storing a bundle of sequentially conveyed sheets in a stacking tray or the like.

  In general, a sheet post-processing apparatus that prints an image created by a computer, a word processor, or the like with a printing apparatus, aligns a series of printed sheets in a bundle, and performs stapling, glue binding, or the like is widely used. Such a sheet post-processing apparatus is configured as a bookbinding apparatus that binds sheets fed from a supply port, or is attached to a discharge port of a printing apparatus such as a copying machine, and the sheet from the discharge port is removed. It is known as a unit of an image forming system for binding. In particular, an image forming system that outputs in a timely manner every time a business booklet or the like is required has been utilized as on-demand printing.

In such an apparatus, when a finished sheet bundle such as bookbinding is stored, as disclosed in Patent Document 1, for example, one or a plurality of stacker trays are arranged to be movable up and down, and the sheet bundle is sequentially placed on the tray. Are stacked and stored. In the tray lifting / lowering position control, the height of the uppermost sheet is detected by sensor means arranged above the tray near the paper discharge port, and the tray is lowered from this position. In the state where the tray is lowered by a predetermined amount, the subsequent sheet bundle is unloaded from the sheet discharge port and stored on the uppermost sheet. The amount of lowering of the tray provides a slight margin for the maximum thickness of the sheet bundle based on the apparatus specifications. Accordingly, when the thickness of the sheet bundle is several sheets and several tens of sheets, the amount of dropping from the sheet discharge port differs each time, and various considerations are taken for carrying out the sheet bundle. In other words, if the paper is ejected from the paper outlet at high speed, the sheets stacked on the tray may collapse, and if the loading capacity on the tray is increased, the same collapse may occur. There is.
JP-A-8-310759 (FIG. 10)

  As described above, when stacking sheets into a booklet and stacking and storing them in a sheet discharge stacker, the stacking tray is conventionally stored by being lowered a predetermined amount from the sheet discharge port as disclosed in Patent Document 1 described above. . In this case, conventionally, the amount of lowering of the stacking tray is set so as to accept a sheet having the maximum bundle thickness allowed from the apparatus specifications. Accordingly, when a few sheet bundles are carried out from the paper discharge port, which are relatively thin, the sheet bundle is carried out on the tray with a high drop, and the already loaded sheet bundle may collapse.

In particular, when a device configuration that stores a bundle of sheets bound in a booklet shape in an inverted posture inclined at a predetermined angle, the conventional tray lowering method has a large interval between the uppermost sheet already stacked and the sheet bundle to be fed out. Therefore, the fed sheet bundle may fall down.
This is because the gap between the stacked sheets becomes larger as the drop with the sheet discharge opening is larger and the thickness of the fed sheet bundle is thinner, so that the sheet bundle is collapsed and stacked. Then, the subsequent sheet bundle gradually collapses to a collapsed state, and there is a problem that a predetermined number of sheet bundles cannot be stored.

  Therefore, the present invention provides a sheet post-processing apparatus that can store sheets in a well-ordered manner even if the sheet stack is stacked in a horizontal direction or stacked in a vertically inverted state. It is an issue. Another object of the present invention is to provide a method for stacking sheet bundles that can accommodate sheet bundles in an upright posture in an upright manner.

  In order to solve the above-described problems, the present invention provides sheet holding means for supporting a stack of sheets in a stacking manner in a stack means for storing a bundle of sheets post-processed with staples, adhesive glue or the like. The sheet holding unit includes a shift unit that moves backward in accordance with the stacking amount of sheets, a control unit thereof, and a sheet bundle thickness detection unit that detects the thickness of the sheet to be post-processed. The control unit is configured to vary the backward movement amount of the sheet holding unit based on the thickness information from the sheet bundle thickness detection unit. The stacking means is provided with a paper surface abutting regulating member for abutting and aligning the uppermost sheet supported by the sheet holding means. The shift means moves to a carry-in standby position that is a predetermined distance away from the carry-in entrance when the sheet is carried in, and moves so that the uppermost sheet is abutted and aligned with the paper surface abutment regulating member after carrying in the sheet. That is, the shift unit is configured to move the sheet holding unit to a position retracted by a predetermined amount from the carry-in entrance when the sheet is carried in, and to move toward the paper surface abutting restriction member at the carry-in port after carrying in the sheet.

  Next, in the stacking method of the present invention, the step of moving the sheet holding means for supporting the post-processed sheets in a stack form to a carry-in standby position spaced a predetermined amount from the sheet carry-in port, and the sheet holding means at the carry-in standby position And a step of moving the sheet holding means to the sheet carry-in entrance side and abutting and aligning the uppermost sheet against the paper surface abutting restriction member after carrying the sheet bundle. The carry-in standby position of the sheet holding means is set according to the thickness of the bundle of sheets carried in. In this case, as for the thickness of the sheet bundle, for example, the thickness of the sheet bundle is detected in the process of collecting the sheets in a bundle and performing post-processing.

  In the present invention, when the sheet bundle is stored in the stack unit that stores the post-processed sheet bundle, the amount of backward movement from the sheet carry-in port of the sheet holding unit that supports the sheet bundle in a stack shape is determined by the thickness of the sheet bundle. Therefore, the sheet bundle carried in from the carry-in entrance is received by the sheet holding means at a position corresponding to the thickness thereof, so that the sheet bundle is neatly arranged on the already stored sheet bundle. Loaded and stored. Therefore, the sheet bundle from which the sheet bundle from the carry-in port is already stored can be stored with good alignment without breaking the alignment of the sheet bundle or causing a paper jam. In particular, the sheet bundles can be stacked in a tight state without any risk of falling when the sheet bundles are stacked one after another in an inverted orientation and no extra space is created between the sheet bundles.

  The present invention will be described in detail below based on the preferred embodiments shown in the drawings. FIG. 1 shows an image forming apparatus comprising a bookbinding apparatus (sheet post-processing apparatus) B incorporating a sheet post-processing apparatus C of the present invention as a unit, and an image forming apparatus A for feeding a printing sheet to the bookbinding apparatus B. 1 is an overall configuration diagram of a system. FIG. 2 is an enlarged explanatory view of a main part of the bookbinding apparatus B, and FIG. 3 is an explanatory view of a sheet bundle storage part of the bookbinding apparatus B.

  As shown in FIG. 1, the image forming system of the present invention comprises an image forming apparatus A such as a copying machine, a printer, and a printing machine, and a bookbinding apparatus B attached downstream of the image forming apparatus A. The illustrated apparatus is further provided with a finisher apparatus D on the downstream side of the bookbinding apparatus B. First, the image forming apparatus A includes a paper feed unit 10, a printing unit 20, and a paper discharge unit 30, and a plurality of print sheets having a predetermined standard size are stored in the paper feed cassette 11. The paper feed cassette 11 is provided with paper feed means for separating and feeding the print sheets one by one, and the print sheet of the designated size is fed out to the paper feed path 12. A printing means 21 such as a printing drum is disposed in the paper feed path 12, and the illustrated one shows an electrostatic printing apparatus.

  A developing device 24, a laser transmitter 22, and a cleaning blade 23 are arranged around the photosensitive drum (printing means) 21, and an electrostatic latent image is formed on the photosensitive member by the laser transmitter 22. An image is transferred onto a printing sheet by a transfer charger 25 with toner attached thereto, and fixed by a fixing device 26 disposed on the downstream side. The printed sheet thus subjected to the printing process is sent to a paper discharge path (paper discharge unit) 30 and is carried out from a paper discharge port 31. Further, a circulation path 32 is continuously provided in the paper discharge path 30, and a print sheet printed on one side is switched back to reverse the conveyance direction, and then is reversed and circulated to the printing unit 20. Then, after printing on the back side, the paper is discharged from the paper discharge port 31. The paper discharge outlet 31 is provided with a paper discharge tray that normally stores and accommodates print sheets. In the present system, the next bookbinding apparatus B is attached to the paper discharge outlet 31.

  The bookbinding apparatus B includes a sheet carry-in path 40 that receives a print sheet from the paper discharge port 31 of the image forming apparatus A, a sheet stacking unit 41 that aligns and aligns the sheets from the sheet carry-in path 40 in a bundle, A post-processing unit 42 that applies adhesive glue to one edge of the sheet bundle from the sheet stacking unit 41 (the back part at the time of bookbinding) and binds it in a booklet shape, and a stack unit 43 that stores the post-processed sheet bundle. Has been. Further, grip conveying means 44 for conveying the sheet bundle S1 from the sheet stacking means 41 to the post-processing position is provided, and the sheet bundle S1 accumulated in a substantially horizontal posture by the sheet stacking means 41 is set in a substantially vertical posture orthogonal to this. And the lower end edge of the sheet bundle S1 is positioned at the post-processing position (the illustrated one is the glue application position). The post-processing means 42 may be constituted by a stapling apparatus that staples the sheet bundle S1. However, in the illustrated example, the post-processing means 42 is “adhesive” for binding and mounting the sheet bundle S1 with a cover sheet. The application means 45 ”and the“ binding means 46 ”of the sheet bundle S1 and the cover sheet are configured. Further, the post-processing means 42 shown in the figure is provided with “cutting means 47” for trimming and cutting the peripheral edge of the sheet bundle bound with the cover sheet.

  On the other hand, a cover sheet conveyance path 48 for feeding a cover sheet is branched in the sheet carry-in path 40, and the cover sheet conveyance path 48 includes a post-processing path 49 for conveying the sheet bundle S1 by the grip conveyance means 44. It is arranged to intersect. A cover sheet on which a title or the like is printed by the image forming apparatus A is supplied to the cover sheet conveyance path 48 via a path 48 to an intersection F which will be described later. On the other hand, the cover sheet may be supplied from an inserter device (not shown) prepared separately from the image forming apparatus. In this case, the cover sheet conveyance path 48 can be configured as a path independent of the sheet carry-in path 40.

  A binding means 46 is disposed at the intersection (shown by arrow F) between the cover sheet conveyance path 48 and the post-processing path 49. The binding means 46 matches the center of the sheet bundle S1 with the center line of the cover sheet at the intersection F between the cover sheet fed from the cover sheet conveyance path 48 and the sheet bundle S1 fed from the post-processing path 49. In this state, it is composed of a folding blade 46a and a folding roll 46b that fold the cover sheet. A pair of left and right folding blades 46a are provided at the intersection F, and are configured to be press-contacted and separated from each other. The folding roll 46b is disposed on the downstream side of the folding blade 46a and is composed of a pair of roller members facing each other. The back sheet is formed by pressing the sheet bundle S1 and the cover sheet that are abutted in an inverted T shape by the folding blade 46a and the folding roll 46b, and at the same time, the sheets are bound together with the adhesive paste applied to the sheet bundle side. Hereinafter, the sheet bundle in this state is referred to as a booklet sheet.

  On the downstream side of the binding means 46, a cutting means 47 for cutting the peripheral edge of the folded booklet sheet S2 is disposed in the post-processing path 49. The cutting means 47 includes a turntable 47a for turning the booklet sheet S2, a press means 47c for pressing and holding the booklet sheet S2, and a cutting blade 47b for cutting the periphery of the booklet sheet. The turntable 47a is configured to grip and turn the booklet-like sheet S2 from the folding roll 46b, and to position the periphery of the sheet in the order of, for example, the top portion, the ground portion, and the fore edge portion at the downstream cutting position. The pressing means 47c is composed of a pedestal member and a movable press member that face each other with the booklet sheet S2 interposed therebetween, and fixes the booklet sheet S2 at a cutting position. The cutting blade 47b is constituted by a flat blade cutter and is configured to reciprocate by a cutter motor Mc so as to cut a booklet sheet S2 fixed at a cutting position.

  The bookbinding apparatus B configured in this way sequentially receives the print sheets carried out from the paper discharge port 31 of the image forming apparatus A from the sheet carry-in path 40, and accumulates them on the sheet stacking means 41 to align them. The sheet bundle S1 is converted into a vertical posture by the grip conveying means 44, adhesive glue is applied to the lower end edge thereof by the adhesive applying means 45, and the sheet is bound and bound to the cover sheet by the downstream binding means 46. The booklet sheet bound in this way is trimmed and trimmed at the periphery by the cutting means 47 as necessary, and is carried out to the stack means 43 described later.

  As shown in FIG. 1, a discharge path 50 is connected to the cover sheet conveyance path 48, and a finisher device D is connected to the discharge path 50. The finisher apparatus D stores the print sheet not subjected to the bookbinding process from the image forming apparatus A to the sheet discharge tray 51 via the sheet carry-in path 40 and the cover sheet conveyance path 48. Further, the finisher D can be provided with post-processing functions (not shown) such as stapling, punching, and stamping, which are different from the bookbinding processing described above. Since the mechanism is known, explanation is omitted.

  Therefore, the present invention is a booklet-like sheet processed by the above-described post-processing means 42 (the illustrated one is composed of “adhesive application means 45”, “binding means 46” and “cutting means 47”). The stack means (stack device) 43 for storing S2 has the following configuration. FIG. 3 is a cross-sectional view showing the overall configuration of the stacking means 43, and FIG. 4 is a conceptual explanatory view showing the movement operation of the sheet holding means incorporated therein.

  The stack unit 43 includes a sheet holding unit that stacks and holds the booklet sheet S2 that has been post-processed in the post-processing path 49, and a housing 60 that is disposed on the downstream side of the post-processing path 49 described above. It is comprised with the sheet | seat holding means (sheet holding tray 61 mentioned later) arrange | positioned. The housing 60 is formed in an appropriate shape (the illustrated one is a box shape) for accommodating the booklet-shaped sheet S2, and the maximum load capacity is determined according to the apparatus specifications. The housing 60 is provided with sheet holding means (hereinafter referred to as a sheet holding tray) 61 for supporting the sheets in a stacked form. As shown in FIG. 3, the sheet holding tray 61 is composed of a tray member that backs up and supports the back surface of the booklet sheet S2 in an inverted posture inclined at a predetermined angle from the horizontal direction.

  On the other hand, the booklet-like sheet S <b> 2 whose back surface is supported by the sheet holding tray 61 is supported by a carrier belt 62 disposed on the bottom surface portion of the housing 60 at its lower end surface (back portion). The sheet holding tray 61 is supported in the sheet storage area of the housing 60 so as to be movable in the sheet placement direction (left and right direction in FIG. 3). Although not shown, a guide rail is provided on the bottom of the housing 60 in the left-right direction in FIG. 3, and a sheet holding tray 61 is movably fitted and supported on the guide rail. The carrier belt 62 is a non-supporting belt and is supported between a pair of pulleys 62a and 62b so as to be movable in the left-right direction in FIG. The sheet holding tray 61 is connected to the carrier belt 62 by fixing means such as screws, and a tray stepping motor M1 (hereinafter referred to as a stepping motor) is connected to one of the pulleys 62a. The illustrated stepping motor M1 is a stepping motor capable of forward and reverse rotation.

  Accordingly, the sheet holding tray 61 is configured to be movable in the sheet storage direction of the housing 60. Shift means for moving the sheet holding tray 61 backward according to the stacking amount of the booklet-like sheets S2 serves as the stepping motor M1 and the carrier belt 62. It will be composed of. This shift means is controlled by a control means constituted by a control CPU 71 described later.

  Thus, if the stepping motor M1 is rotated forward and backward, the sheet holding tray 61 reciprocates in the left-right direction in FIG. 3, and simultaneously, the carrier belt 62 also reciprocates left and right by the same amount as the sheet holding tray 61. A sensor 61S shown in the figure is provided on the carrier belt 62 and detects a home position of the sheet holding tray 61. The position detection will be described later. In addition, 62S shown in the figure is a sensor flag attached to the carrier belt 62. As described above, the housing 60 equipped with the sheet holding tray 61 and the carrier belt 62 is supported on the apparatus frame 63 so as to be movable in the drawing direction in the front-rear direction of FIG. 3, that is, the front side of the bookbinding apparatus B (the surface direction in FIG. 1). Has been. This is because the booklet sheet S2 on the sheet holding tray 61 is taken out with the housing 60 being pulled out to the front side of the apparatus.

  Further, the housing 60 is provided with a carry-in port 64 for the booklet-like sheet S2 arranged on the downstream side of the post-processing means 42, and a bundle carry-out roller 65 is arranged on the upstream side of the carry-in port 64. is there. Incidentally, the entire housing 60 shown in FIG. 3 is opened, and a part of the housing 60 constitutes the carry-in port 64. Reference numeral 80 shown in FIG. 3 denotes a box for storing cutting waste, which is disposed below the cutting means 47 and adjacent to the housing 60. A flapper member 81 is swingably disposed in the box 80.

  The flapper member 81 is constituted by a plate-like plate, and a base end portion is rotatably supported and has a motor (not shown) built therein. When the booklet-shaped sheet S2 is cut by the cutting blade 47b, the cutting waste is housed in the box 80 by swinging to the left in FIG. After cutting, the sheet is returned to the illustrated position and retracted to the broken line position on the right side of the drawing so as not to hinder the sheet unloading by the bundle unloading roller 65. The flapper member 81 also functions to push down the booklet sheet S2 accommodated in the stack means 43 toward the sheet holding tray 61 as will be described later.

  Therefore, in the present invention, in order to control the position of the sheet holding tray 61 by the stepping motor M1, a sheet bundle thickness detecting means is provided on the upstream side of the bundle carry-out roller 65. The sheet bundle thickness detecting means includes a sensing method for directly detecting the thickness of the sheet bundle on the upstream side of the bundle carrying-out roller 65 and a counting method for counting the number of sheets passing through the path. The former sensing method can detect the thickness of the bundle with a simple configuration if it is arranged in a means for nipping the sheet bundle in the post-processing path 49 such as the grip conveying means 44 and the pressing means 47c. The grip conveying means 44 has a pair of grippers, one of which is a fixed side gripper (moves itself but does not move in the sheet bundle direction), and the other is a movable side gripper.

  When the movement amount of the gripping operation of the movable gripper is detected from the reference position by, for example, a linear sensor, the thickness of the gripped sheet bundle can be detected. In the latter counting method, for example, the number of sheets carried out to the sheet stacking means 41 (the illustrated one is a tray) is counted, and the thickness of the sheet bundle is calculated from the counted number and the sheet thickness (for example, the average thickness). calculate. The number of sheets is counted by counting the signal from the sheet detection sensor with a counter.

  Next, the structure of the sheet holding tray 61 and the carrier belt 62 will be described in detail with reference to FIG. As described above, the sheet holding tray 61 and the carrier belt 62 that hold the booklet sheet S2 from the carry-in port 64 in the housing 60 need to gradually move backward according to the stacking amount. The sheet holding tray 61 and the carrier belt 62 are supported so as to be movable in the left-right direction in FIG. 4 as described above, and the stepping motor M1 is connected to the carrier belt 62. Therefore, the sheet holding tray 61 is supported so as to be movable between the home position Hp and the maximum stacking position Mp of the sheet holding tray 61 drawn by a broken line, with the position indicated by Hp in FIG. 4 as the home position. It is reciprocated by 62 stepping motors M1. The sheet holding tray 61 can reciprocate between the illustrated home position Hp and the maximum stacking position Mp, and a paper surface abutting restriction member that abuts and aligns the uppermost sheet on the sheet holding tray 61 at the home position Hp. 67 is provided.

  Therefore, the sheet holding tray 61 moves between the next carry-in standby position Fw and the alignment position (tray home position position Hp; hereinafter the same). First, the carry-in standby position Fw is a tray position when the booklet sheet S2 is carried in from the carry-in port 64 by the bundle carry-out roller 65, and this carry-in standby position Fw is set to Fw = (Ld + LS). In this case, Ld is the bundle thickness of the booklet sheet S2 to be carried in, and is a detection value of the above-described sheet bundle thickness detecting means. LS is a stroke of the alignment operation, and is set to a constant value such as 10 mm in advance. Next, the alignment position is set to a position moved from the carry-in standby position Fw to the home position side by (movement amount = LS), and the position where the uppermost sheet supported by the sheet holding tray 61 abuts against the paper surface abutting restriction member 67. It is. When the sheet holding tray 61 is positioned at the carry-in standby position Fw, it is possible to move it back to the left side of the drawing and then move forward to the right side so as to be positioned at the carry-in standby position Fw. Prevent the effects of.

  Then, the sheet holding tray 61 is moved from the alignment position to the carry-in standby position Fw by the discharge instruction signal, and is moved to the alignment position after the booklet sheet S2 is loaded. A control configuration for this will be described with reference to FIG. FIG. 5 is a block diagram showing the configuration of the control CPU 71 of the bookbinding apparatus B, and shows only the control unit related to the movement of the sheet holding tray 61. The control CPU 71 includes a ROM 72, a RAM 73, and a timer unit 74. The ROM 72 stores a control program corresponding to the operation procedure shown in FIG. 6, and the control CPU 71 executes the control program and executes control operations of respective units described later. At this time, the control CPU 71 reads out control data (reference data for each post-processing operation) stored in the RAM 73, and the timer unit 74 is configured to measure the operation time of each unit.

  A home position sensor 61S of the sheet holding tray 61 is connected to an input port of the control CPU 71. Further, the control CPU 71 calculates the total thickness of the booklet sheets stored in the stacking means (sheet holding tray 61), and the sheet holding tray based on the information from the integrating means 71a. A tray movement amount calculation means 71b for setting the position 61 is provided. A drive circuit 76 for the stepping motor M1 is connected to the output port of the control CPU 71. The drive circuit 76 includes a power source 77 and a pulse generator 78, and is configured to rotate the stepping motor M1 stepwise in the forward and reverse directions by the number of steps specified by the tray movement amount calculating means 71b. Further, the control CPU 71 includes a serial interface unit (I / O), and exchanges control data and control signals with the control unit of the image forming apparatus A.

  The operation procedure of the control program will be described with reference to FIG. As the final process, the post-processing means 42 described above finishes the booklet sheet S2 which is bound and bound on the cover sheet by trimming and cutting the peripheral edge with the cutting means 47 (S100). The bundle thickness (Ld) of the post-processed booklet sheet is stored in the RAM 73 as a detected value from the sheet bundle thickness detecting means arranged in the post-processing path 49 described above. When all scheduled (set) post-processing is completed as described above, the control CPU 71 stores the booklet sheet S2 from the bundle carry-out roller 65 into the stack means 43 as follows.

  First, the control CPU 71 receives the operation timing of the post-processing means 42 described above, for example, the operation end signal (S101) of the cutting means 47, the control CPU 71 sets the stepping motor M1 (shift means), and the sheet holding tray 61 is in the carry-in standby position. Control to move to Fw. First, the tray movement amount calculating means 71b reads the bundle thickness (Ld) of booklet sheets to be carried in and the alignment stroke (LS) that is set and stored in advance from the RAM 73, and the carry-in standby position of the sheet holding tray 61 is read. The amount of backward movement to Fw (the aforementioned (Ld + LS)) is calculated. Then, the control CPU 71 sends a power pulse corresponding to the backward movement amount to the drive circuit 76. Then, the stepping motor M1 rotates by the designated number of steps, the carrier belt 62 moves to the left in FIG. 4, and the sheet holding tray 61 fixed thereto also moves backward (S102). The position of the sheet holding tray 61 at this time is moved from the state of FIG. 7A to the state of the carry-in standby position Fw shown in FIG. 7B, and the uppermost sheet already stacked on the sheet holding tray 61 and the home position. An interval (Ld + LS) that secures the bundle thickness (Ld) and alignment stroke (LS) of the booklet-like sheets to be carried in is formed between Hp.

  When the sheet holding tray 61 is moved backward to the carry-in standby position Fw by the above operation, the stepping motor M1 moves backward (Ld + LS) from the alignment position in FIG. 7A and stops or is set in advance. The vehicle moves backward to the position where the surplus movement amount is overrun, moves forward from this position, moves to the loading standby position Fw, and stops. Concurrently with the movement of the sheet holding tray 61 to the carry-in standby position Fw, the control CPU 71 starts to rotate the bundle carry-out roller 65 after the estimated movement time of the sheet holding tray 61 (S103). Then, the booklet-shaped sheet S2 is sent to the carry-in port 64 in the state shown in FIG. 7B in a substantially vertical posture with the edge (back) to which the adhesive is applied facing down. Thereafter, the booklet-shaped sheet S2 is detached from the bundle carry-out roller 65, and the lower end edge (back part) of the booklet sheet S2 falls on the carrier belt 62 and enters the housing 60 (S104).

  Next, the control CPU 71 stops the bundle carry-out roller 65 after the expected time (indicated by “T1” in the drawing) that the booklet sheet S2 enters the housing 60. Then, the control CPU 71 rotates the flapper member 81 counterclockwise as shown in FIG. 8A to push down the booklet sheet S2 that has entered from the vertical direction toward the sheet holding tray 61, and then the flapper member 81 rotates clockwise. To return to the original position. After the reciprocating operation of the flapper member 81, the control CPU 71 aligns the booklet sheet S2 stored and held in the sheet holding tray 61 by rotating the stepping motor M1 in the opposite direction (forward direction) (S105).

  That is, when the sheet holding tray 61 is at the carry-in standby position Fw, an interval larger than the booklet sheet bundle thickness (Ld) by the alignment stroke (LS) is formed between the carry-in entrance 64. This is to ensure that the booklet sheet S2 is carried into the stacking means without being buffered. For this reason, a space is created between the stored booklet sheet and the already stored booklet sheet. The gap G) is equal to or smaller than the alignment stroke (LS) (G ≦ LS) (see FIG. 8A).

  Therefore, the control CPU 71 advances the sheet holding tray 61 to the right side in the drawing by the alignment stroke (LS). In this state, as shown in FIG. 8B, the booklet sheet S2 is tightly stored on the sheet holding tray 61 in an orderly manner. At this time, the sheet holding tray 61 is sequentially retracted to the left in the figure by the thickness of the booklet-like sheet that has been loaded. Thus, the storage of the booklet-shaped sheet S2 is completed, and the subsequent booklet-shaped sheet is prepared for carrying out (S106).

Next, a stacking method of sheet bundles (booklet-like sheets) according to the present invention will be described with reference to the configuration of the above-described sheet post-processing apparatus. The method includes the following first to third steps.
"First step"
A step of moving the sheet holding means for supporting the post-processed sheet bundle in a stacked state to a carry-in standby position Fw separated from the carry-in entrance 64 by a predetermined amount (Step 1 in FIG. 6). As described above, the sheet holding means (sheet holding tray 61) is moved back to the carry-in standby position Fw separated by a predetermined amount from the carry-in entrance 64 by the sheet bundle discharge timing signal and waits by the shift means (stepping motor M1). To do. The carry-in standby position Fw is set to (Ld + LS) so as to secure a bundle thickness (Ld) and alignment stroke (LS) of the booklet-like sheets to be carried in (sheet home reference).
"Second step"
Carrying the sheet bundle into the sheet holding means (sheet holding tray 61) at the carry-in standby position Fw; The sheet holding tray 61 carries the sheet bundle into the stack means in the state of the carry-in standby position Fw (Step 2 in FIG. 6). The above-described apparatus includes a bundle carry-out roller 65 and a control CPU 71 that controls the rotation of the bundle carry-out roller 65.
"Third step"
After carrying in the sheet bundle, the sheet holding means (sheet holding tray 61) is moved to the carry-in entrance 64 side to abut the uppermost sheet against the paper surface abutment regulating member 67 (Step 3 in FIG. 6). The sheet bundle carry-in entrance 64 is configured by a paper surface abutting restriction member 67, for example, a side wall of a housing 60 that houses the sheet bundle. The sheet holding tray 61 is moved forward to the restricting member to abut the uppermost sheet bundle. As a result, the gap between the stacked sheet bundles is removed, and the sheet bundles are held tightly and orderly in the tray. Accordingly, the carry-in standby position Fw of the sheet holding means is set according to the thickness (Ld) of the carried-in sheet bundle.

  Although the present invention has been described in detail above, the post-processing means in the present invention has shown the case where the booklet sheet is bound and bound with the cover sheet, but the booklet sheet can be simply bound without being mounted with the cover sheet. Of course, as a means for binding the sheet bundle, it is of course possible to heat-stap with a staple binding means or a heat-sensitive adhesive tape instead of the adhesive application means. In addition, the case where the above-mentioned post-processing means is constituted by “adhesive application means”, “binding means”, and “cutting means” has been described. However, the peripheral edge of a sheet bundle bound to an apparatus or booklet that does not include this cutting means Even in an operation mode without cutting, the above-described configuration of the present invention is not changed and can be employed. Sheet bundle stacking means

1 is a schematic configuration diagram of an image forming system including a sheet post-processing apparatus of the present invention. Sectional drawing which shows the principal part of the sheet | seat post-processing apparatus in the system of FIG. Explanatory drawing which shows the structure of the stack means in the apparatus of FIG. 3 is a conceptual explanatory diagram of the movement control of the sheet holding tray in the stack means. The block diagram which shows the control structure in the apparatus of FIG. The flowchart which shows the control action in the apparatus of FIG. FIGS. 3A and 3B are diagrams illustrating a state in which a sheet bundle is stored in a sheet holding unit in the apparatus of FIG. 2, where FIG. 3A illustrates an initial state of the sheet holding unit, and FIG. FIGS. 3A and 3B are diagrams illustrating a state in which the sheet bundle is stored in the sheet holding unit in the apparatus of FIG. 2, in which FIG. 2A illustrates a state in which the sheet bundle is carried into the sheet holding unit, and FIG. Each is shown.

Explanation of symbols

A Image forming apparatus B Bookbinding apparatus (sheet post-processing apparatus)
D finisher device 43 stacking means 61 sheet holding means (sheet holding tray)
61S Home position sensor 62 Carrier belt 67 Paper surface impact regulating member 71 Control CPU
71a Total load accumulation means LS Alignment stroke M1 Shift means (stepping motor)
Fw loading standby position

Claims (6)

A sheet post-processing apparatus that collects sheets sequentially delivered in a bundle and performs post-processing,
Stacking means for sequentially stacking and storing post-processed sheet bundles from the sheet carry-in port;
A sheet holding means provided in the stack means for supporting the post-processed sheet bundle in a stack;
Shift means for moving the sheet holding means backward according to the stacking amount of the sheet bundle;
Control means for controlling the shift means;
Sheet bundle thickness detecting means for detecting the thickness of the sheet bundle to be subjected to the post-processing,
The sheet post-processing apparatus, wherein the control unit varies the amount of backward movement of the sheet holding unit based on thickness information from the sheet bundle thickness detection unit. The stack means is provided with a paper surface abutting restriction member that abuts and aligns the uppermost sheet supported by the sheet holding means,
The control means moves the shift means to a carry-in standby position where the sheet holding means is spaced a predetermined amount from the sheet carry-in entrance when carrying the sheet bundle, and after carrying the sheet bundle, the uppermost sheet is pushed against the paper surface abutting restriction member. The sheet post-processing apparatus according to claim 1, wherein the sheet post-processing apparatus is controlled so as to be aligned. The backward movement amount of the sheet holding unit is set to a movement amount corresponding to a distance calculated from the sheet bundle thickness from the sheet bundle thickness detection unit and a preset alignment stroke,
3. The sheet post-processing apparatus according to claim 2, wherein the shift unit moves the sheet holding unit from the paper surface abutting restriction member to a loading standby position corresponding to the movement amount when the sheet bundle is loaded. The control means includes an integrating means for calculating the thickness of the entire sheet bundle supported by the sheet holding means,
3. The sheet post-processing apparatus according to claim 2, wherein the control unit sets a loading standby position of the shift unit after the sheet bundle is loaded based on sheet bundle thickness information from the integrating unit. 5. The sheet holding unit according to claim 1, wherein the sheet holding unit is disposed on the stack unit with a predetermined angle in a substantially vertical direction, and holds the sheet bundle from the sheet carry-in port in an inverted posture. The sheet post-processing apparatus according to the item. A stacking method of sheet bundles in a sheet post-processing apparatus that performs post-processing by stacking sequentially conveyed sheets in a bundle,
Moving the sheet holding means for supporting the post-processed sheet bundle in a stack to a standby position spaced apart from the sheet carry-in port by a predetermined amount;
Carrying a sheet bundle into the sheet holding means at the carry-in standby position;
After the sheet bundle is carried in, the sheet holding means is moved to the sheet carry-in side and the uppermost sheet is abutted and aligned with the paper surface abutting restriction member.
A method for stacking sheet bundles in a sheet post-processing apparatus, wherein the carry-in standby position of the sheet holding means is set according to the thickness of the sheet bundle to be carried in.

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