JP6357329B2 - Post-processing apparatus and image forming system using the same - Google Patents

Description

  The present invention relates to a post-processing apparatus that stacks a plurality of sheets for each copy and finishes the folding process, and relates to an improvement in a folding processing mechanism that performs a folding process on the stacked sheet bundle.

  In general, this type of apparatus is known as a post-processing apparatus for an image forming apparatus, which is a bookbinding finishing apparatus that stacks image-formed sheets in a stacking unit and binds the central part of the sheet and then folds the sheet. .

  For example, in Patent Document 1, a finishing mode in which sheets formed by being connected to a paper discharge port of an image forming apparatus are stacked in a first processing unit and bound and processed in a second processing unit. An apparatus is disclosed that selectively executes a finishing mode of folding after processing.

  In this document, the sheet sent to the conveyance path is distributed and conveyed to the first processing unit and the second processing unit, and the second processing unit collects and stacks the sheets, and then binds the central portion thereof. Thus, a magazine binding mechanism for folding is disclosed. In this mechanism, the sheet is folded and then stored in the storage stacker from the paper discharge path.

  Further, Patent Document 2 discloses a mechanism in which a press mechanism for pressing a fold position of a sheet bundle is arranged on the downstream side of a folding roll, and the crease portion is pressurized by this pressing means and then conveyed to a stacker. Yes.

JP 2008-184324 A JP 2013-47144 A

  As described above, an apparatus that performs folding processing after stacking image-formed sheets for each copy and binding is already known. In order to reliably fold the fold position with such a fold processing mechanism, it is also known to dispose a pressure mechanism (increase fold mechanism) that presses the fold position downstream of the fold processing mechanism. As this additional folding mechanism, a mechanism that presses the fold position with a press plate or a mechanism that presses the fold position with a roller pair is known.

  However, in the conventional additional folding mechanism, a constant pressing time is set regardless of the progress of the subsequent sheet stacking process. Accordingly, whether the additional folding pressurizing time on the downstream side of the folding mechanism is set during the time when the subsequent sheets are accumulated and folded, or the folding process of the subsequent sheet is executed after the additional folding process is performed. It was selected at any timing.

  Accordingly, in the apparatus control for simultaneously executing the discharge operation of the preceding sheet and the stacking operation of the subsequent sheet, the subsequent sheet can be quickly and repeatedly folded without delaying the subsequent sheet stacking operation (from the image forming unit to the folding process). It was impossible to proceed with the accumulation of subsequent sheets at the same time.

  In the present invention, when the sheets are continuously accumulated and folded, the time for press forming at the crease position of the preceding sheet is set according to the progress of the subsequent sheet accumulation, so that an efficient folding process can be performed. An object of the present invention is to provide a post-processing device that can be used.

In order to achieve the above object, the present invention is characterized in that the conveyance of the folded sheet is stopped in order to maintain the pressure of the pressure means while the conveyed sheet is folded by the folding processing unit .

Further, the configuration will be described in detail. A conveyance path (12) for conveying sheets, a stacking section (B1) for stacking and stacking sheets sent from the transport path, and a folding processing section for folding the sheet bundle of the stacking section (B2), a paper discharge path (37) for transferring the folded sheet of the folding processing section to the downstream storage section (B4), and a pressurizing means (D) arranged in the paper discharge path for pressing the folded sheet, Control means (46) for controlling the pressing time of the folded sheet by the pressing means.

  The control unit is configured to set the pressurizing time based on a subsequent operation time until a sheet following the stacking unit is stacked and folded.

  In the present invention, the pressurizing time of the pressurizing unit disposed between the folding processing unit and the paper discharge unit is set according to the subsequent operation time until the succeeding sheets are stacked on the stacking unit and folded. Therefore, the following effects are achieved.

  The sheet folded by the folding processing unit is not carried out to the storage unit as it is, and is pressed by the pressing unit until the succeeding sheet is stacked on the stacking unit through the upstream discharge path. Since it continues, the fold position is surely folded.

  Further, since the pressurizing time for the pressurizing means is until the succeeding sheets are stacked on the stacking unit, the folding process can be speedily continued without waiting for the succeeding sheet folding process. .

  Further, according to the present invention, the pressurizing unit is configured by a pair of conveying rollers positioned on the upstream side of the paper discharge unit, so that the folded sheet can be additionally formed with a simple structure without disposing a special pressurizing mechanism. .

1 is an explanatory diagram of an overall configuration of an image forming system according to the present invention. FIG. 2 is an explanatory diagram illustrating a configuration of a post-processing device in the image forming system of FIG. 1. Explanatory drawing of the principal part in the post-processing apparatus of FIG. 4A and 4B are explanatory views of a pressure unit (pressure means) in the explanatory view of FIG. 3, in which FIG. 3A is a front view of the pressure unit in the paper discharge direction, and FIG. It is a conceptual diagram which controls the pressurization unit in the post-processing apparatus of FIG. 3, (a) is explanatory drawing of a unit structure, (b) is explanatory drawing of the setting of pressurization time. FIG. 2 is a block diagram showing a control configuration in the image forming system of FIG. 1. 7 is a part of a flowchart showing a procedure of post-processing operations in the control configuration of FIG. 6. The flowchart which shows the procedure following FIG. 7 of the post-processing operation | movement in the control structure of FIG. FIG. 3 is an explanatory diagram of a layout configuration in which trimmer units are arranged in a paper discharge path in the post-processing apparatus of FIG. 2.

  The present invention will be described in detail below based on the embodiments shown in the drawings. FIG. 1 shows an image forming system, which includes an image forming apparatus A and a post-processing apparatus B. The post-processing apparatus B includes a stacking unit B1 that stacks sheets sent from the image forming apparatus A for each copy (for each group), a folding processing unit B2 that performs a folding process on the stacked sheet bundle, and a folding process. A storage portion B4 for storing the sheet bundle is incorporated.

  The present invention is characterized in that in the post-processing apparatus B, a paper discharge area Ar is provided on the downstream side of the folding processing section B2, and the trimmer unit C and the additional folding pressurizing unit D are selectively arranged in this area. Hereinafter, the post-processing apparatus B and the image forming apparatus A will be described in this order.

[Post-processing equipment]
The configuration of the post-processing apparatus B will be described with reference to FIGS. 2 is an explanatory diagram of the overall configuration of the post-processing apparatus B, FIGS. 3 and 4 are explanatory diagrams of a detailed configuration of the paper discharge unit B3, and FIG. 5 is an additional folding pressure unit disposed in the paper discharge unit. It is control explanatory drawing of D. FIG.

  As shown in FIG. 2, the post-processing apparatus B includes an apparatus housing 10 and first and second post-processing sections 13 and 25 (which may be constituted by one post-processing section) disposed in the housing. And a conveyance path 12 for feeding the sheet from the carry-in port 11 to the post-processing section, and a storage section B4 for storing the post-processed sheet.

  The first post-processing unit 13 includes a post-processing mechanism that stacks the sheets sent from the conveyance path 12 on the processing tray 14 and performs binding processing, and stores the sheet bundle in the stack tray 15. The second post-processing unit 25 stacks the sheets sent from the conveyance path 12 on the stacking guide 26 and stacks them. After the folding process, the second post-processing unit 25 passes through the downstream discharge area Ar and receives the magazine tray 27 (folded sheet storage). Part; the same shall apply hereinafter).

  In the paper discharge area Ar, a trimmer unit C for cutting the sheet bundle folded at the upstream folding processing section B2 and an additional folding pressurizing unit D are selectively arranged as optional units. That is, the apparatus housing 10 supports the folded sheet substantially linearly, and a paper discharge area Ar for trimming cut or incremental folding press molding is disposed between the folding processing section B 2 and the magazine tray 27.

  As shown in FIG. 2, the conveyance path 12 is configured by a straight path (which may be a curved path) for guiding a sheet from the path carry-in port 11 to the path sheet discharge port 16, and a path branch port at the center of the path. 12a is arranged. Then, the sheet supplied to the carry-in port 11 is transferred from the paper discharge port 16 to the first post-processing unit 13 disposed downstream thereof, and from the path branch port 12a to the second post-processing unit disposed downstream thereof. The sheet is guided to 25 (folding processing section B2 described later).

  For this reason, a pair of rollers (first roller pair 17, second roller pair 18, third roller pair 19, fourth roller pair 20) for conveying the sheet is arranged in the conveyance path 12, and a drive motor (not shown) (hereinafter referred to as "conveyance"). A motor)). The carry-in port 11 has a carry-in roller 17 (the first roller pair) and a sheet sensor (inlet sensor) Se1, and the paper discharge port 16 has a paper discharge roller 20 (the fourth roller pair) and a sheet sensor (discharge roller). A paper sensor Se2 is arranged.

  Further, a conveyance roller 18 (the second roller pair) and a path switching unit 21 are disposed at the path branch port 12a. An actuator such as an operating solenoid (not shown) is connected to the path switching means 21. In the illustrated conveyance path 12, a buffer path 12 b for temporarily retaining the sheet sent from the carry-in entrance 11 toward the first post-processing unit 13 is disposed. The sheet sent from the carry-in entrance 11 by the forward / reverse rotation of 19 (the third roller pair) is temporarily retracted and retained in the path.

  The first post-processing section 13 is provided with a sheet end regulating means 22 for positioning the sheet on the processing tray 14 and a side alignment means (not shown) for positioning the sheet side, and a sheet sent from the conveyance path 12 is predetermined. Are collected in a bundle. The processing tray 14 is provided with stapling means 23 (unit) for binding the bundled sheets. 24 is an elevating roller that guides the sheet sent from the conveyance path 12 to the processing tray 14, and simultaneously guides the sheet one by one to the processing tray, and simultaneously stacks the bundle of sheets after the binding processing on the downstream stack tray 15. To guide.

  In the second post-processing unit 25, a branch path 28 is disposed in a different transport direction from the path branch port 12a of the transport path 12, and is disposed on the downstream side of this path. The second post-processing unit 25 (folding processing unit; the same applies hereinafter) includes a stacking guide 26 for stacking and storing sheets, a binding processing unit 29 disposed in the guide and binding the stacked sheets (bundles), The folding unit 30 is configured to fold the accumulated sheet bundle.

  The stacking guide 26 is constituted by a guide member (plate member) that stacks and stores sheets sent from the upstream branch path 28, and the illustrated stacking guide 26 is arranged in the vertical direction of the apparatus housing 10. A leading end regulating stopper 31 that locks the leading end of the sheet is disposed at the lower end of the stacking guide 26. The illustrated tip regulating stopper 31 is attached to the apparatus frame so as to be slidable (slider bree) along the accumulation guide 26, and moves the position of the sheet according to the size.

  The folding processing means 30 includes a folding roll means 32 and a folding blade means 33 for folding the sheet bundle accumulated on the accumulation guide from the center. The folding roll means 32 is composed of a pair of rollers that are in pressure contact with each other, and is connected to a drive motor (not shown) (hereinafter referred to as a “folding processing motor”) that is rotatable in the direction of folding the sheet bundle. The folding blade means 33 is composed of a plate member for inserting the fold position of the sheet bundle between the nips of the pair of folding rolls, and is connected to the shift motor M1 by a rack-pinion mechanism.

  The folding roll means 32 is composed of a pair of rollers that are pressed against each other or a pair of rollers that can be pressed and separated from each other, and tightly clamps the sheet bundle when folding the sheet bundle. Further, in the case where the roller pair is configured so as to be able to be pressed and separated, the sheet bundle is pressed when folded, and after the folded, it is separated to prevent the rear end portion of the sheet from being wrinkled and damaged.

  The configuration of the paper discharge unit B3 will be described with reference to FIG. A paper discharge unit B3 is disposed on the downstream side of the folding processing unit B2. As shown in FIG. 3, a paper discharge unit B3 is disposed between the folding processing unit B2 and a storage unit B4 (described later). The paper discharge unit B3 includes a paper discharge guide member 35 for placing the folded sheet bundle and a pair of carry-out rollers (which may be belts) 36 for conveying the sheet. The illustrated discharge guide member 35 is configured by a paper guide that guides the sheet in the discharge direction, and the carry-out roller pair 36 is configured by first, second, and third roller pairs 36a, 36b, and 36c. Each roller pair 36a to 36c is connected to a paper discharge motor (not shown), and each roller is configured to rotate in the paper discharge direction at the same peripheral speed.

  In particular, the apparatus shown in the figure is an additional folding and pressing unit (pressurizing unit) that press-forms a folded sheet with the first, second, and third unloading roller pairs 36a, 36b, and 36c (three pairs are not necessarily required). Pressure means D). The carry-out roller pair 36 is disposed at a position where at least one third conveyance roller pair 36c is close to the fold position of the folded sheet bundle.

  As shown in FIG. 4A, the pair of carry-out rollers 36a, 36b, and 36c are arranged so as to press the entire folded sheet S at an interval, and one of the third conveying roller pair 36c is a sheet folding member. It arrange | positions in the position which presses the eye position X. Further, the width direction of the pair of carry-out rollers 36 is arranged so as to press the entire length of the sheet width substantially uniformly as shown in FIG.

  As described above, in the paper discharge unit B3, the paper discharge area Ar that stores the maximum size length of the folded sheet S in the transport direction is arranged on the downstream side of the folding processing unit B2, and the pressurizing unit D (additional pressure) is added to this area. Pressure unit) and a trimmer unit C, which will be described later, are selectively mounted (optional equipment).

  Therefore, according to the present invention, when the folded sheet S is transported from the folding processing section B2 to the paper discharge section B3, the folded sheet is pressed for a predetermined time with the stationary state, or the folded sheet is fed at a low speed for a predetermined time. It features a control mechanism that presses.

  The carry-out roller pair 36 (pressure means) described above is connected to a paper discharge motor (not shown). The discharge motor control means 40 (control CPU or the like) stops the carry-out roller 36 or decelerates and conveys it at a low speed when the sheet sent from the folding processing section B2 is carried into the discharge area Ar. . The roller stop time or the roller low-speed rotation time is varied according to the subsequent operation time T in which subsequent sheets are stacked on the stacking unit B1.

  In other words, the folded sheets are not discharged straight to the storage unit B4, and the folded sheets are discharged to the extent that no conveyance trouble occurs according to the progress of the operation from the stacking unit B1 of the subsequent sheets to the folding process B2. After waiting in the paper area Ar, the paper is stored in the storage unit B4.

  For this reason, the control means 40 is comprised as follows, for example. As shown in FIG. 5B, the timer 41 that counts the CPU clock resets the counter at the end of the folding processing operation (for example, the retracting operation of the folding blade means 33) and starts the timer. Then, the folded sheet is conveyed to a predetermined paper discharge area Ar and pressurized by the carry-out roller pair 36. At this time, the carry-out roller pair 36 is maintained in a stopped state or a low speed state.

  The control means 40 “monitors subsequent operations” simultaneously with the timer activation. The subsequent operation is monitored by whether the sheet following the preceding sheet stayed in the paper discharge area Ar is (1) “monitoring the stacking status of the subsequent sheet conveyed to the stacking unit B1” (hereinafter referred to as stacking operation monitoring). (2) One of the methods of “monitoring the folding processing operation of the subsequent sheets stacked in the stacking unit B1 (hereinafter referred to as stacking / folding operation monitoring)” is adopted simultaneously with the stacking operation monitoring.

  When the “stacking operation monitoring” is used, the number of preceding sheets on the downstream side is increased on a case-by-case basis when the succeeding sheet is a few sheets of minimal folding and a few hundred sheets. Can be folded. In other words, the folding time of the preceding sheet is set short in the case of the minimal folding processing bookbinding, and the folding time of the preceding sheet is set long in the case of the maximum folding processing binding.

  Accordingly, a time loss in which the subsequent sheet processing operation is interrupted to execute the additional folding of the preceding sheet occurs, and a mechanical loss in which the subsequent sheet is interrupted during the stacking of the subsequent sheet and unloaded is caused. Absent.

  When the “stacking / folding operation monitoring” is employed, the subsequent sheet is stacked in the stacking unit B1, and then the total time of the operation time for binding the subsequent sheet and the operation time for the folding process is increased. Can be used for

  Note that the binding processing operation time and the folding processing operation time are substantially constant regardless of the number of sheets in the sheet bundle, so that the folding time of the preceding sheet is substantially set according to the number of sheets of the subsequent sheets. It is also possible to configure.

  The configuration of the paper discharge unit B4 will be described. On the downstream side of the paper discharge path 37, a magazine tray 27 for storing sheets that have been folded is disposed.

[Image forming apparatus]
The image forming apparatus A is disposed on the upstream side of the above-described post-processing apparatus B, forms an image on the sheet, and sends the image from the paper discharge port 60 to the downstream post-processing apparatus B. The illustrated image forming apparatus A includes a paper feed unit 51, an image forming unit 52, a paper discharge unit 53, and a data processing unit 54 in an apparatus housing 50.

  The sheet feeding unit 51 includes sheet stackers 51a, 51b, and 51c (sheet feeding cassettes) for forming images, and feeds sheets of a size selected by the operator to the image forming unit 52 on the downstream side one by one.

  The image forming unit 52 forms an image with the image data designated on the sheet of the size selected and fed from the paper feeding unit 51. As the image forming mechanism, various image forming mechanisms such as an electrostatic printing mechanism, an ink jet printing mechanism, a transfer ribbon printing mechanism, a thermal printing mechanism, and an offset printing mechanism can be adopted.

  The illustrated electrostatic printing mechanism will be described. A latent image is formed on the photosensitive drum 55 by an optical beam (light emitter) 56, and a toner ink is attached by a developing device 57 to form an image on the drum surface. Then, the image is transferred by the charger 58 to the sheet sent from the paper feeding unit 51. The paper discharge unit 53 heats the sheet sent from the charger 58 to fix the image, and transfers the sheet from the paper discharge path 59 to the paper discharge port 60. A duplex path 61 is connected to the paper discharge port 60, the conveyance direction of the sheet carried out from the paper discharge port 60 is reversed (switchback conveyance), the sheet is reversed, and the sheet is fed to the image forming unit 52 again. Then, after the image is formed on the back side of the sheet, it is carried out from the paper discharge port 60.

  A scanner unit 62 shown in the figure is a platen 63 for setting an original, a reading carriage 64 for scanning the original on the platen and reading an image, and an image for transferring the read image data to the data processing unit 54 of the image forming apparatus A. A processing unit 65 is provided.

  66 is a feeder unit that separates the original sheets set on the paper feed stacker 67 one by one and feeds them to the platen 63, and stores the original sheets after reading in the paper discharge stacker 68.

[Control configuration]
A control configuration in the image forming system of FIG. 1 will be described. The illustrated system includes an image formation control unit 43 and a post-processing control unit 46. The image forming control unit 43 includes a mode selecting unit 44 and an input unit 45, and controls the image forming apparatus A according to an image forming mode set by an operator. At the same time, the post-processing mode set by the mode selection unit 44 is transferred to the post-processing control unit 46 as a command.

  The post-processing control unit 46 includes a stacking operation control unit 46a, a binding processing operation control unit 46b, a folding processing operation control unit 46c, and a paper discharge operation control unit 46d. The paper discharge operation control unit 46d is provided with a subsequent operation monitoring unit 47 and a pressurizing unit control unit 48.

The subsequent operation monitoring unit 47 is configured by one of the following methods.
(1) “End of subsequent operation” is determined based on a job end signal (end of image forming job of subsequent sheet) transmitted from the control unit 43 of the image forming apparatus A.
(2) The “following operation end timing (expected)” of the succeeding sheet is determined from the sheet number information of the succeeding sheet sent from the control unit 43 of the image forming apparatus A and the image forming conditions.
(3) “Subsequent operation end timing (expected)” is determined from the sheet detection signal from the sensor arranged in the conveyance path 12 and its counter.
(4) The conveyance end timing of the subsequent sheet is determined from the interval of the sheet detection signal from the sensor arranged in the conveyance path 12.

  Next, an operation flow in the sheet folding processing operation will be described with reference to FIGS. When the sheet is loaded from the upstream image forming apparatus A, the control unit 46 of the post-processing apparatus B receives the sheet from the carry-in port 11 of the conveyance path 12 (sheet carry-in; St01). The control unit 46 drives the conveyance unit in the conveyance path 12 to convey the sheet. At this time, the control means 46 guides the sheet sent from the carry-in entrance 11 from the branch path 28 to the folding processing section B2 (path transport; St02). Then, the sheets are stacked in a stack on the stacking guide 26, and the posture in the direction perpendicular to the sheet discharge is aligned with the reference position by an alignment unit (not illustrated) (sheet stacking and alignment; St03).

  The control means 46 determines whether or not the sheet carried into the stacking unit B1 is the final sheet, and when it is the final sheet, the process proceeds to the next step. This determination employs a method of determining based on a job end signal from the image forming apparatus A (final sheet determination; St04). When the staple processing is designated, the control means 46 moves to the staple binding position in the stacked sheet bundle (staple processing; St05). Then, the fold position of the sheet bundle is bound by the binding processing unit 29 (binding processing operation; St06). In this case, the sheet bundle is moved by moving the front end regulating stopper 31 by the shift motor M1.

  After the binding processing operation is completed, the control unit 46 moves the sheet bundle from the binding position to the folding position. This movement is performed by the rotation of the shift motor M1 (sheet folding position feed; St07). Then, the control means 46 executes the folding process position of the sheet bundle (folding process; St08). This folding process is performed by rotation of the folding roll means 32 and movement of the folding blade means 33 from the standby position to the operating position.

  Next, the control means 46 transfers the sheet carried out from the folding roll means 32 to the paper discharge area Ar. The folded sheet is transferred by rotating the carry-out roller pair 36 (folded sheet discharge path transfer; St09). Then, the control means 46 determines whether there is a subsequent sheet (St10).

"When there is no subsequent sheet"
The control means 46 determines whether to perform additional folding molding or a setting command at the time of setting the post-processing mode, and when not performing additional folding, the process proceeds to step St14 (St11). Further, the control means 46 stops the pair of carry-out rollers 36 when the rear end of the folded sheet S is detected by a sensor (not shown) when performing additional folding. At this time, the folded sheet S is nipped by the carry-out roller pair 36 and stopped in the discharged area Ar (previous sheet pressure forming start; St12).

  The control means 46 determines whether or not a predetermined pressurization time has elapsed (St13). This pressurization time is set from the time lapse signal from the means for monitoring the subsequent sheet stacking operation as described above, or from the estimated time. Then, the control unit 46 carries out the preceding sheet when the predetermined pressurizing time has elapsed (preceding sheet discharge; St14). In this carry-out operation, the carry-out roller pair 36 is driven and rotated by a paper discharge motor. Then, the preceding sheet is stored in the storage section B4 (magazine tray) on the downstream side (stacker storage; St15).

"When there is a subsequent sheet"
If “following sheet is present” in step St10, the control means 46 determines whether to perform overfolding or from a setting command when the post-processing mode is set (increase folding; St16). When the folding is not increased, the process proceeds to the sheet carrying-out operation in step St20. In addition, a pressurizing time is set when performing additional folding.

  At the same time, the control unit 46 guides the succeeding sheet from the transport path 12 to the stacking unit B1 and executes the stacking operation in parallel (stacking and aligning the succeeding sheet; St22). Then, for example, the job end signal of the succeeding sheet is also received from the image forming apparatus A, and the completion operation or the expected time of the succeeding sheet is monitored (following sheet job end; St023).

  The control means 46 sets the pressurizing time by the pressurizing means D from the monitoring means (pressurizing time setting; St17). Then, the sheet is retained in the sheet discharge area Ar and pressurization of the preceding sheet is started (preceding sheet pressurization start; St18). Therefore, the control means 46 determines whether or not a predetermined set time has elapsed (St19). When the predetermined time has elapsed, the control means 46 activates the paper discharge motor to rotate the carry-out roller pair 36 in the paper discharge direction (preceding sheet discharge; St020). Then, the preceding sheet is stored in the magazine tray 27 (stacker storage; St021).

B1 Stacking unit B2 Folding unit B3 Discharging unit B4 Storage unit Ar Discharging area D Additional folding pressurizing unit 12 Transport path 12a Path branching port 25 Second post-processing unit 26 Stacking guide 27 Magazine tray 28 Branching path 32 Folding roll Means 33 Folding blade means 35 Paper discharge guide member 36 Unloading roller pair 36a First roller pair 36b Second roller pair 36c Third roller pair 37 Paper discharge path 46 Post-processing control section 47 Subsequent operation monitoring means 48 Pressure means control means

Claims (5)

Conveying means for conveying the sheet;
A stacking unit for forming a sheet bundle sheet fed from said conveying means and collecting the product,
A folding unit to form a sheet folding and folding process the sheet bundle in the stacking unit,
A paper discharge path for discharging the folded sheet downstream from the folding processing unit;
And pressing means for transporting while being disposed in the discharge path pressurize the folded sheet in the thickness direction of the sheet,
Control means for controlling the operation of the pressurizing means;
With
The post-processing apparatus, wherein the control unit stops conveying the folded sheet so as to maintain the pressurization of the pressurizing unit while the subsequent sheet is folded by the folding processing unit. Conveying means for conveying the sheet;
A stacking unit that stacks sheets sent from the transport unit to form a sheet bundle;
Binding means for binding the sheet bundle of the stacking unit;
A folding processing unit for folding the sheet bundle of the stacking unit to form a folded sheet;
A paper discharge path for discharging the folded sheet downstream from the folding processing unit;
A pressure unit that is arranged in the sheet discharge path and conveys the folded sheet while pressing the folded sheet in the thickness direction of the sheet;
Control means for controlling the operation of the pressurizing means,
The control means stops the conveyance of the folded sheet so as to maintain the pressure of the pressure means while the subsequent sheets are bound by the binding means. Conveying means for conveying the sheet;
A stacking unit that stacks sheets sent from the transport unit to form a sheet bundle;
Binding means for binding the sheet bundle of the stacking unit;
A folding processing unit for folding the sheet bundle of the stacking unit to form a folded sheet;
A paper discharge path for discharging the folded sheet downstream from the folding processing unit;
A pressure unit that is arranged in the sheet discharge path and conveys the folded sheet while pressing the folded sheet in the thickness direction of the sheet;
Control means for controlling the operation of the pressurizing means,
The control means stops conveying the folded sheet so as to maintain the pressure of the pressure means while the subsequent sheets are bound by the binding means and further folded by the folding processing section. A post-processing device characterized by. The control means stops the conveyance of the folded sheet so as to maintain the pressure of the pressure means in a state where the rear end of the folded sheet folded by the folding processing unit is in the paper discharge path. The post-processing apparatus according to any one of claims 1 to 3. An image forming unit for forming a sheet processing image;
A post-processing unit for post-processing the sheet sent from the image forming unit;
Consisting of
The post-processing unit, an image forming system, which is a post-processing apparatus according to any one of claims 1 4.

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