Post-processing device, image forming device, and image forming system

Abstract

The present invention provides a post-processing device, an image forming device, and an image forming system that can suppress the reduction in the handling efficiency of sheet conveyance defects even when equipped with a conveying path correction structure that improves the overlap accuracy of sheet end portions. The post-processing device includes a first conveying mechanism that conveys sheets conveyed along a first conveying path downstream, a second conveying mechanism that conveys sheets along a second conveying path, and a third conveying mechanism that conveys sheets along a third conveying path. The sheets are circulated in the order of the first conveying path, the second conveying path, and the third conveying path, and a plurality of sheets are overlapped. When the sheets merge from the third conveying path to the first conveying path, the conveying path correction component is provided that directs the conveying direction of the sheets conveyed from the circulating path toward the first conveying mechanism. The conveying path correction component has a retraction mechanism that can retract from a merging position, which is a position where the sheets merge from the third conveying path to the first conveying path.

Description

Technical Field

[0001] The present invention relates to a post-processing device, an image forming apparatus having the post-processing device, and an image forming system. Background Art

[0002] Known post-processing devices perform processes such as aligning multiple sheets of sheet-like media by overlapping them and aligning their ends, and folding the overlapped sheets. Furthermore, known image forming devices that form images on sheets include image forming devices that also include a post-processing mechanism for the sheets on which images are formed, and image forming systems that connect a post-processing device and an image forming device.

[0003] A post-processing device is disclosed that aligns a plurality of sheets into an overlapping state by bringing the leading end of the sheet into contact with a conveying roller and folds the sheets, and includes a circulation path (see Patent Document 1).

[0004] The circulation path disclosed in Patent Document 1 has a configuration in which a sheet is branched downstream of a folding conveying member that performs a folding process, and is circulated and conveyed upstream of the folding conveying member to be overlapped with a subsequent sheet.

[0005] In this conventional arrangement, when a subsequent sheet collides with the conveying rollers that convey the sheet toward the folding conveyor, the subsequent sheet bends. The preceding sheet, having circulated and returned, then moves toward the conveying rollers, following the bent subsequent sheet. This increases the conveying distance of the preceding sheet compared to a case where the subsequent sheet does not bend, and the conveying distance between the preceding and subsequent sheets increases.

[0006] Patent Document 1 does not consider or disclose a structure for preventing the increase in the conveying pitch caused by the deflection of the subsequent sheet. Therefore, in the prior art, there is a problem of suppressing the "deviation" of overlapping multiple sheets using a circulation path.

[0007] To address this issue, a mechanism for correcting the conveyance path of the preceding sheet can be provided. However, this mechanism must be provided near the confluence of the circulation path and the input path. Therefore, if a sheet jam (paper jam) or other conveyance failure occurs near the confluence, the mechanism for correcting the conveyance path will hinder sheet removal. This is a major factor in reducing the ability to handle conveyance failures.

[0008] An object of the present invention is to provide a post-processing apparatus capable of suppressing a decrease in the handling efficiency due to sheet conveyance defects even when provided with a conveyance path correction structure that improves the accuracy of overlapping sheet ends.

[0009] [Patent Document 1] (Japanese) Patent Publication No. 2015-016975 Summary of the Invention

[0010] In order to solve the above-mentioned technical problems, one embodiment of the present invention relates to a post-processing device, which comprises: a first conveying mechanism, which conveys the sheet conveyed along the first conveying path downstream; a second conveying mechanism, which conveys the sheet along the second conveying path, and a third conveying mechanism, which conveys the sheet along the third conveying path. The post-processing device circulates the sheet in the order of the first conveying path, the second conveying path, and the third conveying path, and overlaps multiple sheets. It is characterized in that when merging from the third conveying path to the first conveying path, the post-processing device has a conveying path correction component that directs the conveying direction of the sheet conveyed from the circulation path toward the first conveying mechanism, and the conveying path correction component has a retreat mechanism that can retreat from the merging position, and the merging position is the position where the sheet merges from the third conveying path to the first conveying path.

[0011] According to the present invention, even if a conveyance path correction structure that improves the accuracy of superposition of sheet end portions is provided, it is possible to suppress a decrease in the handling efficiency due to sheet conveyance defects. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 FIG. 1 is a side view of an embodiment of an image forming apparatus including a post-processing device according to the present invention.

[0013] Figure 2 FIG. 1 is a diagram schematically illustrating the configuration of an embodiment of an image forming system according to the present invention.

[0014] Figure 3 The figure shows a module example of the control structure involved in the above embodiment.

[0015] Figure 4 FIG. 1 is a diagram showing the internal structure of a sheet folding device as an embodiment of a post-processing device according to the present invention.

[0016] Figure 5 The figure shows an enlarged view of the internal structure of one step of the folding and conveying operation in the sheet folding device.

[0017] Figure 6 The figure shows an enlarged view of the internal structure of one step of the folding and conveying operation in the sheet folding device.

[0018] Figure 7 The figure shows an enlarged view of the internal structure of one step of the folding and conveying operation in the sheet folding device.

[0019] Figure 8The figure shows an enlarged view of the internal structure of one step of the folding and conveying operation in the sheet folding device.

[0020] Figure 9 The figure shows an enlarged view of the internal structure of one step of the folding and conveying operation in the sheet folding device.

[0021] Figure 10 The figure shows an enlarged view of the internal structure of one step of the folding and conveying operation in the sheet folding device.

[0022] Figure 11 The figure shows an enlarged view of the internal structure of one step of the folding and conveying operation in the sheet folding device.

[0023] Figure 12 The figure shows an enlarged view of the internal structure of one step of the folding and conveying operation in the sheet folding device.

[0024] Figure 13 The figure shows an enlarged view of the internal structure of one step of the folding and conveying operation in the sheet folding device.

[0025] Figure 14 The figure shows an enlarged view of the internal structure of one step of the folding and conveying operation in the sheet folding device.

[0026] Figure 15 (a) to (c) are enlarged views of the internal structure of a comparative example of the embodiment of the sheet folding device.

[0027] Figure 16 (a) to (c) are explanatory diagrams of the conveyance path correction operation in the sheet folding device.

[0028] Figure 17 (a)-(b) are explanatory diagrams of the envisioned issues of the conveyance path correction mechanism in the sheet folding device.

[0029] Figure 18 (a)-(b) are operation explanatory diagrams of an example of the conveyance path correction mechanism in the sheet folding device.

[0030] Figure 19 FIG. 1 is a structural diagram showing an example of a conveyance path correction mechanism in the sheet folding device.

[0031] Figure 20 (a) to (d) are explanatory diagrams showing an operation example of the conveyance path correction mechanism in the sheet folding device.

[0032] Figure 21 (a)-(b) are operation explanatory diagrams of another example of the conveyance path correction mechanism in the sheet folding device.

[0033] Figure 22 FIG. 1 is a structural diagram showing another example of the conveyance path correction mechanism in the sheet folding device.

[0034] Figure 23 (a)-(b) are structural diagrams showing another example of the conveyance path correction mechanism in the sheet folding device. DETAILED DESCRIPTION

[0035] [Embodiment of Image Forming Apparatus]

[0036] First, an embodiment of an image forming apparatus according to the present invention will be described. Figure 1 1 is an external view of a printer 10 as an image forming apparatus. The printer 10 includes a printing unit 100 as an image forming unit and a folding unit 200 as a post-processing unit connectable to the printing unit 100. Figure 1 As shown, the printer 10 is an internal ejection type, with a folding unit 200 incorporated into a portion of the printing unit 100. In the printer 10, the folding unit 200 can be selected as the ejection destination for recording media (sheets P) with images formed thereon. The internal structure of the folding unit 200 will be described later.

[0037] [Embodiment of Image Forming System]

[0038] Figure 2 FIG. 1 is a schematic diagram showing the general configuration of a printing system 1 as an embodiment of the image forming system according to the present invention. Figure 2 In the example, the printing system 1 is configured by connecting a printer 100a and a folding device 200a as a post-processing device. The printing system 1 operates by conveying a sheet P on which an image has been formed by the printer 100a to the folding device 200a, where the folding device 200a performs a predetermined folding process.

[0039] [Functional composition of control module]

[0040] Next, use Figure 3 The embodiment of the control module for controlling the operation of the printing unit 100 and the folding unit 200 according to this embodiment will be described. Figure 3 As shown, the printing unit 100 includes a printing control section 110 as a control module. The printing control section 110 includes a CPU (Central Processing Unit) 11 , a ROM (Read Only Memory) 12 , a RAM (Random Access Memory) 13 , and a serial I / F 114 .

[0041] The image creation unit 120, image reading unit 130, and operation display unit 140 are connected to the print control unit 110. Each of the image creation unit 120, image reading unit 130, and operation display unit 140 includes components for performing their respective functions. Each component of the image creation unit 120, image reading unit 130, and operation display unit 140 operates based on control signals from the print control unit 110.

[0042] The image creation unit 120 performs image formation processing based on image data on a sheet P, which is a sheet-like recording medium. The image reading unit 130 reads an image formed on the sheet P to obtain image data. The operation display unit 140 functions as both an input unit for inputting operating conditions for the image creation unit 120 or the image reading unit 130, and a display unit for displaying operating results.

[0043] A control program for controlling the image creation unit 120, the image reading unit 130, and the operation display unit 140 is stored in the ROM 112. The CPU 111 reads the control program stored in the ROM 112 and expands it into the RAM 113. The CPU 111 then stores data required for control in the RAM 113 and executes control defined by the control program while using the RAM 113 as a work area.

[0044] In addition, if Figure 3 As shown, the folding unit 200 includes a post-processing control unit 210 as a control module. The post-processing control unit 210 includes a CPU 211 , a ROM 212 , a RAM 213 , and a serial I / F 214 .

[0045] Various loads 220 and various sensors 240 are connected to the post-processing control unit 210. The various loads 220 are rollers and roller pairs, described later. The rollers and roller pairs corresponding to the various loads 220 constitute a conveying roller pair and a folding roller pair, respectively. The various loads 220 are operated by drive motors that rotate and drive the rollers and roller pairs. The drive motors constituting the various loads 220 are operated by a driver 230 that receives instructions from the post-processing control unit 210. The various loads 220 are responsible for controlling the conveyance of the sheet material P serving as the recording medium and for folding the sheet material P.

[0046] The various sensors 240 are sheet detection mechanisms that detect the position of the sheet P within the conveyance path. A plurality of these sensors are disposed within the conveyance path, as described later. The conveyance amount and position of the sheet P, which is the subject of post-processing, are determined based on detection signals output by the various sensors 240 to the post-processing control unit 210, which then executes processing according to a predetermined control program. Furthermore, the position of the sheet P can be determined by the post-processing control unit 210 by calculating the conveyance amount (conveying distance) of the sheet P from the time the leading edge of the sheet P is detected by the sheet detection mechanisms, based on the movement of the various loads 220.

[0047] The control program used by the post-processing control unit 210 to execute the specified processing functions is stored in ROM 212. CPU 211 reads the control program stored in ROM 212 and expands it into RAM 213. CPU 211 then stores the data required for control in RAM 213 and, using RAM 213 as a work area, executes the folding operation defined by the control program. As described above, by executing the control program stored in ROM 212, the post-processing control unit 210 can perform the detection of the sheet P and the conveyance control of the sheet P, which will be described later.

[0048] The print control unit 110 of the printer unit 100 and the post-processing control unit 210 of the folding unit 200 are communicatively connected via serial I / F 114 and serial I / F 214. This communication path allows for the exchange of control commands and information required for, for example, recording medium conveyance control. The folding unit 200 switches recording medium conveyance control, the presence or absence of folding, and the type of folding based on control commands sent from the printer unit 100, information regarding the sheet P, and information regarding the position of the recording medium obtained from various sensors 240.

[0049] The information regarding the sheets P transmitted from the printing unit 100 (print control unit 110) to the folding unit 200 (post-processing control unit 210) includes multiple pieces of information. For example, this information includes information indicating the type of sheet P passed from the printing unit 100 to the folding unit 200, the thickness of the sheet P, the size of the sheet P, and so on. This information also includes information indicating the number of sheets P to be overlapped, the type of folding process performed on the sheet P, and the presence or absence of an image indicating the folding position of the sheet P. Furthermore, the control command transmitted from the printing control unit 110 to the post-processing control unit 210 also includes information indicating whether the passed sheet P corresponds to the last page (final sheet) of the unit to be processed in the aggregate.

[0050] [Embodiment of Post-Processing Device]

[0051] Next, as a first embodiment of the post-processing apparatus according to the present invention, the internal structure of the folding unit 200 will be described. Figure 4 FIG2 is a block diagram schematically showing the internal structure of the folding unit 200. The folding unit 200 includes multiple conveying paths, multiple roller pairs for conveying sheets P along each conveying path and performing folding processing, and multiple sheet detection sensors for detecting the conveyed position of the sheets P. The multiple roller pairs each constitute a conveying mechanism or a folding mechanism.

[0052] The conveying paths provided by the folding processing unit 200 are roughly divided into seven. Figure 4 As shown, there are a first conveying path W1 , a second conveying path W2 , a third conveying path W3 , a fourth conveying path W4 , a fifth conveying path W5 , a sixth conveying path W6 , and a seventh conveying path W7 .

[0053] A plurality of roller pairs are arranged along the first conveying path W1, the second conveying path W2, the third conveying path W3, the fourth conveying path W4, the fifth conveying path W5, and the sixth conveying path W6. Specifically, the roller pairs constituting the zeroth conveying mechanism R0, the first conveying mechanism R1, the second conveying mechanism R2, the third conveying mechanism R3, the fourth conveying mechanism R4, the fifth conveying mechanism R5, and the sixth conveying mechanism R6 are positioned in their respective positions along the conveying path for conveying the sheet material P. The start and stop of rotation of each conveying roller pair, which serves as the conveying mechanism, is controlled by a control program executed by the post-processing control unit 210. This control enables the start and stop of conveying the sheet material P.

[0054] The folding unit 200 also includes multiple transport branching mechanisms. These multiple transport branching mechanisms, for example, switch between states in which the sheet P is transported from the first transport path W1 to the second transport path W2, and states in which the sheet P, which was transported toward the second transport path W2, is transported back toward the first transport path W1. Furthermore, the multiple transport branching mechanisms switch between states in which the sheet P is transported from the second transport path W2 to the first transport path W1 while returning to the third transport path W3 and then to a circulating transport path in which the sheet P is circulated.

[0055] In addition, the transport branch mechanism switches the sheet P so that it is not fed into the circulating transport path but is transported to the fourth transport path downstream of the second transport path W2.

[0056] The transport branching mechanism switches the transport path from the first transport path W1 to the fifth transport path downstream of the second transport path via the third transport path W3 . To switch these transport paths, a plurality of transport branching mechanisms are provided in the folding unit 200 .

[0057] In addition, multiple delivery branches, such as Figures 5 to 14 As shown, the sheet P is configured as a first conveyance branch mechanism J1, a second conveyance branch mechanism J2, and a third conveyance branch mechanism J3. These multiple conveyance branches are included in various loads 220 whose operations are controlled by the post-processing control unit 210. Therefore, the post-processing control unit 210 controls the conveyance path of the sheet P by controlling the operations of the multiple conveyance branches. Furthermore, a first folding mechanism F1 and a second folding mechanism F2 for folding the sheet P are disposed midway along the circulating conveyance path.

[0058] The folding unit 200 has a zeroth conveyance mechanism R0, which serves as an inlet conveyance roller pair, located near the inlet 21 that receives sheets from the printing unit 100. Upon receiving control from the post-processing control unit 210 notifying the discharge of a sheet P from the printing unit 100, the zeroth conveyance mechanism R0 begins rotating under the control of a drive motor that drives the zeroth conveyance mechanism R0. Subsequently, when the leading end of the sheet P reaches the nip between the roller pair of the zeroth conveyance mechanism R0, the zeroth conveyance mechanism R0 conveys the sheet P downstream.

[0059] As described later, the folding unit 200 receives the next sheet P before ejecting the sheet P fed from the printing unit 100 from the downstream exit 22, and performs conveying and folding processing to overlap the previous and subsequent sheets P. Therefore, in the following description, the preceding sheet P is referred to as "previous sheet P1." Furthermore, the sheet P following the preceding sheet P1, or the sheet P received by the folding unit 200 after the preceding sheet P1, is referred to as "subsequent sheet P2." The sheet P received by the folding unit 200 following the subsequent sheet P2 and subjected to the overlapping processing is referred to as "next sheet P3." Furthermore, a plurality of sheets formed by overlapping the plurality of sheets P is referred to as a "sheet bundle Q."

[0060] In addition, the number of sheets P when the overlapping process or the folding process is performed in the folding process unit 200 is not limited to three, and three or more sheets may be processed.

[0061] The first conveying mechanism R1 consists of a pair of rollers that face each other across the first conveying path W1, with a nip formed between the rollers. The first folding mechanism F1 is positioned facing each other between the first conveying path W1 and the second conveying path W2, forming a nip between them. The path guided by this nip directs the preceding sheet P1 from the first conveying path W1 to the second conveying path W2.

[0062] Furthermore, the third conveying mechanism R3 guides the preceding sheet P1, which has been directed to the second conveying path W2, to the third conveying path W3, temporarily stopping the conveyance of the preceding sheet P1 on the third conveying path W3. The preceding sheet P1, temporarily stopped on the third conveying path W3, resumes its conveyance when the following sheet P2 is received from the printing unit 100. Consequently, the preceding sheet P1 returns upstream of the first conveying mechanism R1 on the first conveying path W1 and merges with the following sheet P2. This constitutes a circular conveying path.

[0063] In the above-described loop conveyance path, the preceding sheet P1 and the following sheet P2 overlap to form a sheet bundle Q. Next, the flow of the folding process performed on the sheet bundle Q will be described.

[0064] The sheet bundle Q is folded by the first folding mechanism F1, which operates under the control of the post-processing control unit 210. The sheet bundle Q, folded by the first folding mechanism F1, is then transferred from the second conveying path W2 to the fifth conveying path W5. The fourth conveying mechanism R4, the fifth conveying mechanism R5, and the first folding mechanism F1 are driven by the same drive motor. The drive motor can rotate in both forward and reverse directions. By changing the direction of rotation, the sheet bundle Q, which is a superimposed sheet P1 and a subsequent sheet P2, is conveyed and further folded.

[0065] A branching claw 23 is located immediately after the sixth conveying mechanism R6. The branching claw 23 switches its guiding position depending on whether it is guiding the sheet P (sheet bundle Q) toward the sixth conveying path W6 or toward the seventh conveying path W7. The branching claw 23 can be switched, for example, by a solenoid. Alternatively, a drive mechanism including a motor, gears, or cams may be used in place of the solenoid.

[0066] The sheets P that have passed through the fourth conveyance path W4 or the fifth conveyance path W5 are discharged and stacked on the discharge tray 24 of the folding unit 200. The seventh conveyance path W7 is a path for conveying the sheets P to a post-processing device when a post-processing device is provided downstream of the folding unit 200 as the image forming system. In the post-processing device, post-processing such as alignment and stapling is performed on the folded sheets P or the unfolded sheets P.

[0067] A first sheet detection sensor SN1 is arranged just after the zeroth conveying mechanism R0 in the first conveying path W1. A second sheet detection sensor SN2 is arranged just before the first conveying mechanism R1. A third sheet P detection sensor SN3 is arranged just after the second conveying mechanism R2 in the third conveying path W3. A fourth sheet detection sensor SN4 is arranged just after the third conveying mechanism R3 in the third conveying path W3. A fifth sheet detection sensor SN5 is arranged just after the fourth conveying mechanism R4 in the fourth conveying path W4. A sixth sheet P detection sensor SN6 is arranged just after the fifth conveying mechanism R5 in the fifth conveying path W5. A seventh sheet detection sensor SN7 is arranged just after the sixth conveying mechanism R6 in the sixth conveying path W6.

[0068] [Example of overlapping actions]

[0069] pass Figure 4 The folding unit 200 shown as an example can fold the stacked sheets P into three inner and outer folds. Figures 5 to 10 A series of operations for superimposing two sheets P via the loop conveyance path to generate a sheet bundle Q will be described.

[0070] Figure 5 The figure shows the initial state before the sheet P is conveyed from the printing unit 100 side. Figure 5 In the state, when the leading end of the preceding sheet P1 conveyed from the printing unit 100 reaches the paper discharge port of the printing unit 100 , the post-processing control unit 210 starts the rotation of the zeroth conveyance mechanism R0 .

[0071] By the rotation of the zeroth conveying mechanism R0, as Figure 6 As shown, the preceding sheet P1 is conveyed to the first conveying path W1. In order to convey the preceding sheet P1 to the second conveying path W2 instead of the fourth conveying path W4 and guide it toward the circulating conveying path, the post-processing control unit 210 moves the first conveying branch mechanism J1 to the first conveying branch mechanism J2. Figure 6 location.

[0072] When the leading edge of the preceding sheet P1 conveyed by the zeroth conveyor mechanism R0 is detected by the first sheet detection sensor SN1, a detection signal is transmitted to the post-processing control unit 210. Upon receiving the detection signal, the post-processing control unit 210 calculates the timing at which the amount of protrusion of the leading edge of the sheet P from the gripping position of the first conveyor mechanism R1 reaches a predetermined value. Furthermore, the amount of protrusion of the leading edge of the sheet P from the gripping position of the first conveyor mechanism R1 is defined as "first protrusion amount Δ1." When the first protrusion amount Δ1 is reached, the first conveyor mechanism R1 begins rotating.

[0073] When the leading end of the preceding sheet P1 enters the nip of the first conveying mechanism R1 , the post-processing control unit 210 rotates the first folding mechanism F1 , the second conveying mechanism R2 , and the third conveying mechanism R3 .

[0074] So, if Figure 7 As shown, the preceding sheet P1 is conveyed toward the second conveying path W2 by the operation of the first conveying mechanism R1. Furthermore, it is conveyed toward the second conveying mechanism R2 along the descending slope of the second conveying path W2, and is then conveyed toward the third conveying path W3 by the operation of the second conveying mechanism R2. Then, when the leading edge of the preceding sheet P1 is detected by the fourth sheet detection sensor SN4, a detection signal is transmitted from the fourth sheet detection sensor SN4 to the post-processing control unit 210. Upon receiving the detection signal, the post-processing control unit 210 calculates the timing for the leading edge of the preceding sheet P1 to reach a position corresponding to the second protrusion amount Δ2 after conveyance, after the preceding sheet P1 has been conveyed.

[0075] like Figure 8 As shown, when it is determined that the leading end of the preceding sheet P1 has reached the position corresponding to the second protrusion amount Δ2, the rotation of the first folding mechanism F1, the second conveying mechanism R2, and the third conveying mechanism R3 are stopped, and the conveyance of the preceding sheet P1 is stopped.

[0076] It should be noted that even when the conveyance of the preceding sheet P1 is stopped, the first conveyance mechanism R1 continues to rotate in order to receive the succeeding sheet P2 conveyed subsequently from the printing unit 100 .

[0077] Then, if Figure 9 As shown, after being notified of the detection signal of the front end of the subsequent sheet P2 detected by the first sheet detection sensor SN1, the post-processing control unit 210 conveys the subsequent sheet P2 while restarting the conveyance of the preceding sheet P1 at a timing calculated from the detection of the first sheet detection sensor SN1, and conveys the subsequent sheet P2 while overlapping it in a state where the subsequent sheet P2 is slightly ahead of the preceding sheet P1. This timing is equivalent to the timing when the front end of the subsequent sheet P2 merges with the preceding sheet P1 and the subsequent sheet P2 reaches a position equivalent to the third protrusion amount Δ3. Then, when the front end of the subsequent sheet P2 reaches a position equivalent to the third protrusion amount Δ3, the post-processing control unit 210 restarts the rotation of the second conveying mechanism R2 and the third conveying mechanism R3. Thus, as shown in FIG. Figure 9 As shown, the conveyance of the preceding sheet P1 which had been stopped is resumed.

[0078] Specifically, without stopping the following sheet P2, the following sheet P2 is conveyed while the "timing" is calculated based on the detection of the first sheet detection sensor SN1. Conveyance of the preceding sheet P1 is resumed at this calculated timing. This control allows the following sheet P2 to be conveyed while overlapping, slightly ahead of the preceding sheet P1.

[0079] The third protrusion amount Δ3 is calculated based on the motor speeds of the zeroth conveyor mechanism R0 and the third conveyor mechanism R3, and the distances between the first sheet detection sensor SN1, the second sheet detection sensor SN2, and the fourth sheet detection sensor SN4. The third protrusion amount Δ3 is also used to create a gap between the leading ends of the preceding sheet P1 and the following sheet P2 when they merge in front of the first conveyor mechanism R1.

[0080] Then, the leading end of the preceding sheet P1 and the leading end of the following sheet P2 merge to form a sheet bundle Q, and Figure 10 As shown, the sheet P2 is conveyed downstream through the grip of the first conveying mechanism R1. As described above, control is performed so that the following sheet P2 first strikes the grip of the first conveying mechanism R1, and then the preceding sheet P1 strikes the grip of the first conveying mechanism R1. This allows the timing of merging to be adjusted even when the sheet P2 has not yet merged before the second sheet detection sensor SN2, even when the sheet P2 is not yet merging.

[0081] After that, the post-processing control unit 210 determines whether the setting of the number of overlapped and folded sheets notified from the printing unit 100 is consistent with the number of sheets received. If they are consistent, the folding process described below is performed. If they are inconsistent, the post-processing control unit 210 performs the folding process again. Figures 7 to 9 The processing causes the next sheet P3 (the sheet P following the subsequent sheet P2) conveyed from the printing unit 100 to merge and overlap with the sheet bundle Q. Furthermore, whether the sheet P has been conveyed just before the clamping portion of the second conveying mechanism R2 can be determined, for example, based on the number of driving steps of the motor driving the first conveying mechanism R1. Therefore, the drive motors that rotate and drive each conveying mechanism can be a stepper motor or the like. Alternatively, a DC motor can be used if control is based on timing calculated through detection by various sensors.

[0082] [Effects of Folding Process]

[0083] Next, the flow of the folding process in the folding processing unit 200 according to this embodiment will be described. Figures 11 to 14 This is a diagram illustrating the operation of trifolding the sheet bundle Q received from upstream.

[0084] like Figure 10As described in , the merged sheet bundle Q is directly conveyed by the zeroth conveying mechanism R0 and the first conveying mechanism R1. Then, when the leading end of the sheet bundle Q enters the nip of the first conveying mechanism R1, the sheet bundle Q is conveyed to the fourth conveying mechanism R4.

[0085] The post-processing control unit 210 drives the motor at a time just before the transport to the clamping of the fourth transport mechanism R4, and moves the first transport mechanism R1 and the fourth transport mechanism R4 to the Figure 11 The sheet bundle Q is conveyed from the time the leading end of the sheet bundle Q is detected by the fifth sheet detection sensor SN5 until the leading end of the sheet bundle Q reaches the fourth protrusion amount Δ4.

[0086] Then, the post-processing control unit 210 rotates the first conveying mechanism R1 in the conveying direction so as to move the fourth conveying mechanism R4 (first folding mechanism F1) toward the direction corresponding to the first conveying mechanism R1. Figure 7 The conveying direction shown is reversely rotated so as to convey the sheet bundle Q in the opposite direction (see Figure 12 ) By the reverse rotation of the fourth conveying mechanism R4, the sheet bundle Q is conveyed in the opposite direction.

[0087] On the other hand, Figure 13 As shown, the first conveying mechanism R1 Figure 9 The sheet bundle Q is continuously rotated in the direction shown, thereby conveying the sheet bundle Q. As a result, a bend is formed before the clamping portion of the first folding mechanism F1. The bend enters the clamping portion and performs the first folding, thereby forming a first fold.

[0088] The sheet bundle Q that has undergone the first folding is conveyed to the second conveying path W2, conveyed along the downward slope of the second conveying path W2, and conveyed from the position where the front end of the sheet bundle Q is detected by the third sheet P detection sensor SN3 to the front end of the sheet P reaching the fifth protrusion amount Δ5.

[0089] Then, the post-processing control unit 210 rotates the fourth conveying mechanism R4 (first folding mechanism F1) in the conveying direction and rotates the second conveying mechanism R2 relative to the first conveying mechanism R2. Figure 13 The sheet P is conveyed in the opposite direction by the reverse rotation of the second conveying mechanism R2. On the other hand, the post-processing control unit 210 causes the fourth conveying mechanism R4 (first folding mechanism F1) to rotate in the opposite direction. Figure 13 The sheet P is conveyed by rotating in the direction of continuous rotation. Figure 14 As shown, a bend is formed before the clamping portion of the fifth conveying mechanism R5 (second folding mechanism F2). Then, the bend enters the clamping portion and undergoes a second fold, forming a second fold.

[0090] The sheet bundle Q, having undergone the second folding, passes through the fifth conveyance path W5 and is then conveyed toward the discharge tray 24. The fourth protrusion amount Δ4 and the fifth protrusion amount Δ5 are determined based on the total length of the sheet P and the folding method set for the sheet P (sheet bundle Q). Based on this setting, the post-processing control unit 210 determines the fourth protrusion amount Δ4 and the fifth protrusion amount Δ5 by the rotation amount of the second conveyance mechanism R2 (the number of drive steps of the drive motor).

[0091] In the case of an outward trifold, the first fold is made at a position corresponding to 1 / 3 of the total length of the sheet P from the front end in the conveying direction of the sheet P. Then, the second fold is made at a position corresponding to 1 / 3 on the opposite side of the total length of the sheet P. In the case of an inward trifold, the first fold is made at a position corresponding to 2 / 3 of the total length of the sheet P from the front end in the conveying direction of the sheet P, and the second fold is made at a position corresponding to 1 / 3 on the opposite side of the total length.

[0092] Then, the sheet bundle Q subjected to the second folding is conveyed downstream via the fifth conveyance path W5 by the fifth conveyance mechanism R5 .

[0093] [Comparative Example]

[0094] Here, in order to clarify the features of the embodiments of the present invention, Figure 15 An example of a folding unit 200 without a conveyance path correction component is shown in FIG. Figure 15 The comparative example shown here explains the problems caused by not having a conveyance path correction member.

[0095] Figure 15 (a) illustrates a situation where the preceding sheet P1 circulates through the first conveying path via the loop conveying path, with the following sheet P2 first abutting against the first conveying mechanism R1, in order to overlap the preceding sheet P1 and the following sheet P2. Circle M in the figure indicates the vicinity of the junction of the input path and the loop path.

[0096] Before the subsequent sheet P2 joins the preceding sheet P1, it is conveyed by the zeroth conveying mechanism R0 in a state where it does not collide with the first conveying mechanism R1. Figure 15 As shown in (b), the ideal conveying state is assumed to be one in which the following sheet P2x, like the preceding sheet P1x, does not bend within the first conveying path W1. In this case, the preceding sheet P1x contacts the following sheet P2x at the position of circle M and passes through the ideal conveying path. It is then conveyed along the following sheet P2 to the first conveying mechanism R1. In this case, the preceding sheet P1x and the following sheet P2 can be overlapped in an ideal state.

[0097] But, in fact, it is Figure 15Because the preceding sheet P1 is bent within the first conveyance path W1, as in the case of the subsequent sheet P2x shown in (c), the preceding sheet P1 does not contact the subsequent sheet P2 at the position of the circle M. This causes the preceding sheet P1x to be conveyed longer than if it had passed through the ideal conveyance path. In this case, since the conveyance path length of the preceding sheet P1 is longer than the ideal conveyance state, the conveyance gap between the preceding sheet P1 and the subsequent sheet P2 increases.

[0098] As a result, when the preceding sheet P1 and the following sheet P2 are overlapped, the ends are shifted, and the folded sheet becomes a folded sheet in a state of shifted ends in the subsequent folding process.

[0099] In the folding unit 200 according to the present embodiment described below, by providing a conveyance path correction member that suppresses the above-mentioned conveyance pitch, the accuracy of superimposing the plurality of sheets P can be improved.

[0100] [First embodiment of the conveyance path correction unit]

[0101] Figure 16 The folding unit 200 according to this embodiment includes a path correction unit 250 as a conveyance path correction component. The path correction unit 250 is positioned at the position of the circle M described above, i.e., at the junction of the input path and the circulation path. The path correction unit 250 suppresses the conveyance pitch described in the comparative example, thereby preventing misalignment in the overlapping of multiple sheets P.

[0102] like Figure 16 As shown in (a), the path correction section 250 is arranged at a position where it can correct the conveying direction of the leading sheet P1 that is circulated and transported after its front end enters the first conveying path W1 toward the first conveying mechanism R1. For example, the path correction section 250 is arranged so that the conveying direction of the leading sheet P1 interferes with the conveying direction of the subsequent sheet P2 near the confluence point when the sheet P circulates from the third conveying path W3 to the first conveying path W1. In the process of overlapping a plurality of sheets P, when the conveying directions of the plurality of sheets P interfere, it is necessary to correct the conveying direction of each sheet P in the interfering position to the ideal direction. Therefore, the path correction section 250 in this embodiment includes a plate-shaped member that protrudes from the junction of the guide plate constituting the third conveying path W3 and the guide plate constituting the first conveying path W1 toward the downstream side of the conveying direction.

[0103] When the leading end of the preceding sheet P1 contacts the plate member of the path correction section 250, the preceding sheet P1 is conveyed in the direction along the surface of the plate member.

[0104] Therefore, if Figure 16 As shown in FIG. 2( b ), the plate-shaped member provided in the path correction section 250 corrects the conveyance direction of the preceding sheet P1 toward the first conveyance mechanism R1 near the merging position with the circulating path from which the preceding sheet P1 returns.

[0105] Therefore, if Figure 16 As shown in (c), even if the subsequent sheet P2 bends while abutting against the first conveying mechanism R1, the preceding sheet P1 can abut against the first conveying mechanism R1 in the same manner as the subsequent sheet P2 after the conveying path of the preceding sheet P1 is corrected. As a result, the accuracy of overlapping the ends of the multiple sheets P can be improved.

[0106] Next, use Figure 17 A further problem envisaged by providing the path correction unit 250 will be described. Figure 17 The following example shows a case where a subsequent sheet P2 is poorly conveyed (a paper jam occurs) while being conveyed to the first conveying mechanism R1 via the first conveying path W1 as the input path. To resolve the paper jam, the poorly conveyed subsequent sheet P2 must be removed.

[0107] like Figure 17 As shown in (a), the guide plate 260, which forms part of the wall connecting the third conveying path W3 to the first conveying path W1, is configured to rotate. The guide plate 260 is rotated to form an opening, allowing external access to the first conveying path W1. The user can remove sheets P that have been retained due to conveyance failures by pulling them out of the opening.

[0108] However, if Figure 17 As shown in (b) of FIG, in order to pull the subsequent sheet P2 in the processing direction S and remove it, it is necessary to operate the space for pulling out the subsequent sheet P2 (i.e., the space near the confluence point of the first conveying path W1 and the third conveying path W3). However, since the path correction unit 250 is arranged in this space, it will hinder the removal process. In particular, the plate-like member of the path correction unit 250 protruding toward the confluence point narrows the processing space for the subsequent sheet P2. Therefore, the process of pulling the subsequent sheet P2 out from the guide plate 260 is reduced.

[0109] Thus, when the path correction unit 250 is provided, on the one hand, the accuracy of the overlap can be improved by being able to convey the preceding sheet P1 as desired, but on the other hand, the handling efficiency of the removal process of the subsequent sheet P2 is reduced when a paper jam occurs. In this regard, the path correction unit 250 involved in this embodiment can eliminate the above-mentioned assumed problem.

[0110] Figure 18The operation of the correction guide plate 251 included in the path correction unit 250 according to the present embodiment is exemplified. Figure 18 (a) shows a state where the guide plate 260 is rotated to the outside of the first conveying path W1 and an opening is provided in the first conveying path W1 so that the inside can be operated. Figure 18 In the state shown in (a), the sheet P that has become poorly conveyed inside can be handled and pulled toward the processing direction S to be removed.

[0111] The correction guide plate 251 is configured to rotate its front end in the processing direction S by removing the pulling force of the subsequent sheet P2. The correction guide plate 251 is usually applied in the opposite direction of the processing direction S to guide the sheet P conveyed in the input path to the first conveying mechanism R1. That is, when the correction guide plate 251 applies a force in the processing direction S and the pulling force is greater than the above-mentioned force, Figure 18 As shown in (a), the path correction section 250 is pulled by the subsequent sheet P2 and moves in a direction to retreat from the processing space. Specifically, when removing a sheet P from the conveyance path, the path correction section 250 includes a retreat mechanism that allows it to retreat from the conveyance path based on the force applied in the processing direction. This retreat mechanism is particularly effective when conveyance failure of a sheet P occurs, particularly when the correction guide plate 251 retreats from the third conveyance path W3 to the merging position where the first conveyance path W1 merges with the third conveyance path W3.

[0112] Thereafter, when the subsequent sheet P2 is removed, the force applied to the correction guide plate 251 disappears, and the correction guide plate 251 returns to its original state.

[0113] One end of an elastic member is fixed to the downstream end of the correction guide plate 251 in the conveying direction. The other end of the elastic member is fixed to the frame of the folding unit 200 and urges the correction guide plate 251 in the direction opposite to the processing direction S.

[0114] Therefore, if Figure 18 As shown in (a), the correction guide plate 251 rotates by pulling the sheet P (subsequent sheet P2) in the processing direction (removal direction) when a paper jam occurs, and stays in a position away from the removal process during the process. Then, when the removal of the subsequent sheet P2 is completed, the force applied by the elastic member is applied, as shown in FIG. Figure 18 As shown in (b), it rotates and returns to its original state.

[0115] Next, an example of a detailed configuration of the path correction unit 250 will be described. Figure 19 FIG. 2 is a perspective view of the path correction unit 250 as viewed from the X direction perpendicular to the Y direction as the conveying direction of the sheet P, that is, from the oblique front in the width direction of the sheet P. Figure 19As shown, the path correction portion 250 includes a correction guide plate 251 , an elastic material portion 252 , and a first biasing member 253 .

[0116] The correction guide plate 251 includes a plate member 2511, which is a plate-shaped member that corrects the conveying direction of the preceding sheet P1 conveyed in the circulation path toward the direction of the first conveying mechanism R1 (Y direction), and a plate holding portion 2512 for holding the plate member 2511 in a predetermined position. The plate holding portion 2512 is provided with a rib extending from the X-direction end of the plate member 2511 toward the Z direction to rotatably hold the shaft hole 2313 of the plate member 2511.

[0117] The elastic material portion 252, serving as an elastic member, provided on the plate member 2511 is a plate-shaped member disposed at the downstream end of the plate member 2511 in the conveying direction. It is made of a material softer than the plate member 2511. The elastic material portion 252 is deformable in the vertical direction relative to the conveying direction. The elastic material portion 252 should be flexible enough so that, in the event of a paper jam, it can be deformed in a direction perpendicular to the conveying direction of the sheet P by an external force applied in the processing direction. Furthermore, it should be sufficiently elastic to allow it to return to its original position after the external force applied in the processing direction ceases.

[0118] One end of the first force-applying member 253 is fixed to the end of the plate member 2511, and the other end is fixed to the frame of the folding unit 200. The first force-applying member 253 applies a force upward (in the Z direction) relative to the conveyance direction to the downstream end of the plate member 2511. The force applied by the first force-applying member 253 causes the correction guide plate 251 to return to a predetermined position when the force acting in the processing direction during the removal of the sheet P ceases.

[0119] The correction guide plate 251 is pivotally supported at a predetermined position by inserting a pin fixed to the frame of the folding unit 200 into a shaft hole 2514 formed in the plate holding portion 2512. The correction guide plate 251 then rotates in the ZY plane with the shaft hole 2513 as the rotation center.

[0120] Therefore, when the correction guide plate 251 applies a downward force relative to the conveying direction to the elastic material portion 252 disposed at the downstream end in the conveying direction, the downstream end in the conveying direction rotates when the elastic material portion 252 reaches its deformation limit, thereby being able to retreat from the vicinity of the merging position.

[0121] When the force applied downward in the conveying direction further causes the elastic material portion 252 to deform to a limit where it cannot deform further, the plate member 2511 rotates downward in the conveying direction due to the force applied to the elastic material portion 252. This causes the path correction portion 250 to retreat further from the vicinity of the merging position, ensuring sufficient space for pulling out the subsequent sheet P2 that has jammed.

[0122] Next, use Figure 20 The operation of the path correction section 250 when performing the removal process of the sheet P will be described. Figure 20 (a) illustrates a paper jam condition in which a sheet P stops due to poor conveyance at the junction of the circulation path and the feed path, i.e., the sheet P remains on the conveyance path. In this jam condition, the retained sheet P is pulled downward (in the -Z direction) in the conveyance direction (removal).

[0123] When the sheet P is pulled downward in the conveying direction by the removal process, an external force in the downward direction is applied to the elastic material portion 252 at the end portion of the correction guide plate 251 on the downstream side in the conveying direction. Figure 20 By the deformation of the elastic material portion 252 , the downstream end portion of the correction guide plate 251 in the conveying direction is retracted from the position where the sheet P stays.

[0124] When the sheet P is further pulled, Figure 20 As shown in (c), the external force exceeds the pulling force of the first biasing member 253. As a result, the correction guide plate 251 rotates about the shaft hole 2513, and the downstream end portion in the conveying direction rotates downward (-Z direction).

[0125] Then, if Figure 20 As shown in (c), when the sheet P is removed, the correction guide plate 251 rotates due to the pulling force of the first force applying member 253 and returns to the original position ( Figure 2 The state of 0(a)).

[0126] As described above, when removing a sheet P from the conveyor path, the pulling force used to remove the sheet P causes the path correction unit 250 to retreat from the removal space, facilitating removal. Furthermore, when removing a jammed sheet P, the path correction unit 250 returns to its initial position. This ensures greater processing space during the removal process, improving handling efficiency. Furthermore, since the process automatically returns to its original state upon completion, degradation in handling due to conveying problems can be minimized.

[0127] In this embodiment, the first biasing member 253 is used as an example of the force for returning the correction guide plate 251 to its initial position. However, the member for returning the correction guide plate 251 to its initial position is not limited to this. For example, any member having the property of returning to its original shape after deformation, such as a torsion coil spring, may be used.

[0128] [Second embodiment of the conveyance path correction unit]

[0129] Next, another embodiment of the transport path correction unit included in the post-processing apparatus according to the present invention will be described. Figure 21 The following illustrates a path correction unit 250a, a conveyance path correction component included in the folding unit 200 according to this embodiment. The path correction unit 250a can be retracted upstream in the conveyance direction. After removing a jammed sheet P, it can return to its original position. The "original position" of the path correction unit 250a corresponds to a position where the conveyance direction of the preceding sheet P1 conveyed via the circulation path can be corrected toward the first conveyance mechanism R1.

[0130] When the subsequent sheet P2 fails to be conveyed properly at the confluence position with the circulation path, the jam sensor included in the various sensors 240 outputs a detection signal to the post-processing control unit 210. The post-processing control unit 210 notifies the user of the occurrence of the jam and Figure 21 As shown in (a), the path correction unit 250a is moved toward the zeroth conveying mechanism R0. Figure 21 As shown in FIG. 1 ( a ), the path correction section 250 a can be retracted from the space for removing the sheet P, thereby ensuring a processing space.

[0131] Furthermore, the end portion of the path correcting portion 250a on the downstream side in the conveying direction may be formed of an elastic material, as in the path correcting portion 250. Thus, even if a load is applied to the front end of the path correcting portion 250a during removal of the sheet P, the force generated by the load can be released by bending, thereby making it easier to remove the sheet P.

[0132] Alternatively, the guide plate 260 may be rotated, and a sensor may be used to detect the presence of an opening. The post-processing control unit 210 may trigger the path correction unit 250 to retract using a detection signal from an opening / closing sensor of the guide plate 260 .

[0133] Then, if Figure 21 As shown in (b), when the opening / closing sensor detects that the guide plate 260 is closed, the post-processing control unit 210 only needs to perform a restoration operation to return the path correction unit 250 to its original position.

[0134] Next, an example of a detailed configuration of the path correction unit 250 a will be described. Figure 22 FIG. 2 is a perspective view of the path correction portion 250a viewed from the oblique front in the X direction, which is a direction perpendicular to the Y direction, which is the conveying direction of the sheet P. Figure 22 For example, the path correction portion 250 a includes a correction guide plate 251 a , an elastic material portion 252 a , a second biasing member 253 a , and a solenoid portion 254 .

[0135] The correction guide plate 251a has a plate part 2511a which is equivalent to a plate-shaped part that corrects the conveying direction of the preceding sheet P1 conveyed in the circulation path toward the direction of the first conveying mechanism R1 (Y direction), and a rib protruding in the X direction from the X-direction end of the plate part 2511a to move the correction guide plate 251a to a specified position.

[0136] The elastic material portion 252 a is a plate-shaped member attached so that the end portion of the plate member 2511 a on the downstream side in the conveying direction extends in the conveying direction, and is made of an elastically deformable material.

[0137] One end of the second biasing member 253a is fixed to the moving retaining portion 2512a, which serves as the end of the plate member 2511a, and the other end is fixed to the frame of the folding unit 200. The second biasing member 253a biases the correction guide plate 251a so that it slides upstream in the conveyance direction. The second biasing member 253a is an elastic member that exerts a pulling force to slide the correction guide plate 251a from the merging position to the retracted position.

[0138] When the solenoid portion 254 is in the ON state, it applies force by pulling the moving holding portion 2512a toward the downstream side of the conveying direction. The operation of the solenoid portion 254 is performed by the post-processing control portion 210. In the opening and closing sensor of the guide plate 260, when it is detected that the guide plate 260 is opened, the post-processing control portion 210 turns the solenoid portion 254 OFF. Thus, the correction guide plate 251a is moved toward the upstream side of the conveying direction by the force of the second force-applying member 253a. Then, when the opening and closing sensor detects that the guide plate 260 is closed, the solenoid portion 254 is turned ON. The force of the solenoid portion 254 is set to be stronger than the force of the second force-applying member 253a. Thus, when the solenoid portion 254 is turned on, the correction guide plate 251a is held in the confluence position (refer to Figure 21 (a)).

[0139] [Second embodiment of the conveyance path correction unit]

[0140] Next, another embodiment of the transport path correction unit included in the post-processing apparatus according to the present invention will be described. Figure 23 (a) and Figure 23 (b) is a perspective view of the path correction unit 250b according to this embodiment, viewed from the oblique front in the X direction, which is a direction perpendicular to the Y direction, which is the conveying direction of the sheet P. Figure 22 As shown, the path correction portion 250a includes a correction guide plate 251b and an elastic material portion 252b. The correction guide plate 251b is biased in a predetermined direction so as to rotate about the shaft hole 2513b.

[0141] The correction guide plate 251b has a plate part 2511b which is equivalent to a plate-shaped part that corrects the conveying direction of the preceding sheet P1 conveyed in the circulation path toward the direction of the first conveying mechanism R1 (Y direction), and a rib protruding from the end of the upstream side of the plate part 2511b in the Y direction to rotate the correction guide plate 251b at a specified position.

[0142] The elastic material portion 252 b is a plate-shaped member attached so that the end portion of the plate member 2511 b on the downstream side in the conveying direction extends in the conveying direction, and is made of an elastically deformable material.

[0143] The path correction section 250b receives the subsequent sheet P2 and conveys the preceding sheet P1 that has been circulated toward the first conveying mechanism R1. Figure 23 (a) Exemplary state: At this time, the preceding sheet P1 is conveyed along the correction guide plate 251 b without being affected by the deflection of the following sheet P2 .

[0144] When a conveying failure occurs in the subsequent sheet P2, Figure 23 As shown in (b), the plate member 2511b is rotated about the shaft hole 2513b, thereby allowing the correction guide plate 251b to be retracted from the merging position.

[0145] The correction guide plate 251 b may be rotated by using power from a motor or the like as a driving source, or by using a configuration in which driving force from the driving source is transmitted via gears.

[0146] The folding unit 200 according to the embodiment described above can improve the accuracy of the front end alignment and skew correction of the stacked sheets when performing post-processing including stacking multiple sheets. Furthermore, when conveyance failure occurs in the stacked multiple sheets, the efficiency of removing the defective sheets can be improved.

[0147] Furthermore, the present invention is not limited to the above-described embodiments and various modifications are possible without departing from the technical spirit thereof. The technical matters included in the technical concepts described in the claims are all subject of the present invention. While the above-described embodiments are preferred examples, those skilled in the art can implement various modifications based on the disclosed content. Such modifications are also included within the technical scope described in the claims.

Claims

1. A post-processing device comprising: a first conveying mechanism for conveying the sheet conveyed along the first conveying path downstream; a second conveying mechanism that conveys the sheet along a second conveying path, and a third conveying mechanism that conveys the sheet along a third conveying path, The post-processing device circulates the sheets in the order of the first conveying path, the second conveying path, and the third conveying path, and overlaps the plurality of sheets. It is characterized by: The post-processing device includes a conveyance path correction member for directing the conveyance direction of the sheet conveyed from the circulation path toward the first conveyance mechanism when the sheet merges from the third conveyance path to the first conveyance mechanism. The conveyance path correction member includes a retraction mechanism capable of retracting from a merging position where the third conveyance path merges with the first conveyance path to remove the sheet that has been poorly conveyed. It is characterized in that the conveying path correction component includes: a plate member for correcting a conveyance path of the sheet in the first conveyance path; a biasing member configured to bias the plate member in a direction such that the surface of the plate member faces the first conveying mechanism; The elastic member is provided at a downstream end portion of the plate member in the conveying direction and is deformable in a direction perpendicular to the conveying direction.

2. The post-processing device according to claim 1, characterized in that: The conveyance path correction member is disposed at a position in the first conveyance path where a conveyance direction of a preceding sheet that has been loop-conveyed interferes with a conveyance direction of a subsequent sheet that has been fed.

3. The post-processing device according to claim 1 or 2, characterized in that: When removing the sheet that has become poorly conveyed in the first conveying path, the plate member rotates in a direction perpendicular to the conveying direction to retreat from the merging position, and returns to the merging position after removing the sheet.

4. The post-processing device according to claim 1 or 2, characterized in that: When the plate member removes the sheet that has become poorly conveyed in the first conveying path, the plate member deforms the elastic member by pulling the sheet in the removal direction, and rotates and retreats from the confluence position when the deformation limit of the elastic member is reached, and returns to the confluence position after removing the sheet.

5. The post-processing device according to claim 1 or 2, characterized in that: The plate parts are divided in a direction perpendicular to the conveying direction. When the sheet that is poorly conveyed is removed in the first conveying path, they are respectively rotated in a direction perpendicular to the conveying direction and retreated from the confluence position, and are respectively rotated and returned to the confluence position after the sheet is removed.

6. The post-processing device according to claim 1 or 2, characterized in that: When removing the sheet in the first conveying path, the plate member slides in a direction perpendicular to the conveying direction to retreat from the merging position, and returns to the merging position after removing the sheet.

7. An image forming apparatus comprising an image forming unit for forming an image on a sheet and a post-processing unit for post-processing the sheet, characterized in that: The post-processing unit is the post-processing device according to any one of claims 1 to 6.

8. An image forming system, characterized in that: The present invention is structured by connecting an image forming apparatus having an image forming portion for forming an image on a sheet and a post-processing apparatus according to any one of claims 1 to 6 .

Images