JP5549529B2 - Paper folding apparatus and image forming apparatus - Google Patents

Description

  The present invention relates to a sheet folding device and an image forming apparatus.

  2. Description of the Related Art Conventionally, a sheet post-processing device that is provided at a subsequent stage of an image forming apparatus such as a copying machine and executes stapling processing or folding processing on a sheet is known. In the bending process, the folded sheet (sheet or sheet bundle) may be subjected to a sandwiching process (press process) by a pair of sandwiching members.

JP 2004-210436 A

  However, in the conventional sandwiching process, since the length of the processing section of the sandwiching process is constant, the sandwiching process has been performed wastefully for a sheet that normally requires only a short processing section.

  Therefore, an object of the present invention is to obtain a sheet folding device and an image forming apparatus that can execute the sandwiching process more efficiently.

In the sheet folding device according to the present invention, the folded sheets are opposed to each other along the overlapping direction of the overlapped portions of the folded sheets , and are stacked while moving along the overlapped portions. The sheet by the sandwiching member is variably controlled by a pair of sandwiching members sandwiching the portion and a movement amount of the sandwiching member along the overlapped portion according to at least one of the number and thickness of the sheets. And a control unit that variably controls the length of the sandwiching processing section.

  According to the present invention, since the movement amount of the sandwiching member, that is, the length of the processing section of the sandwiching process can be varied, the sandwiching process can be executed more efficiently.

FIG. 1 is an explanatory diagram showing a schematic configuration of a paper folding apparatus according to an embodiment of the present invention. FIG. 2 is a perspective view of a folding mechanism of the sheet folding device according to the embodiment of the present invention. FIG. 3 is a side view of the folding mechanism of the sheet folding device according to the embodiment of the present invention. FIG. 4 is a perspective view showing a state in which a part of the bending mechanism is removed from FIG. FIG. 5 is a side view of FIG. FIG. 6 is a perspective view showing a state where parts of the bending mechanism are further removed from FIG. FIG. 7 is a side view of the VII portion of FIGS. FIG. 8 is a perspective view showing an internal configuration of a press unit included in the folding mechanism of the sheet folding device according to the embodiment of the present invention. FIG. 9 is a side view of FIG. FIG. 10 is a side view schematically illustrating an example of a press unit included in the folding mechanism of the sheet folding device according to the embodiment of the present invention. FIG. 11 is an explanatory diagram illustrating an example of setting the length of the press section according to the number of sheet bundles in the sheet bending device according to the embodiment of the present invention. FIG. 12 is a diagram illustrating an example of a correlation between the number of sheets or sheet bundles and the length of the press section for each sheet thickness in the sheet bending device according to the embodiment of the present invention. FIG. 13 is a block diagram showing an example of a part of the control circuit of the sheet folding device according to the embodiment of the present invention. FIG. 14 is a block diagram showing an example of a part of the CPU included in the control circuit of FIG. FIG. 15 is a flowchart showing an example of the control of the folding mechanism by the control circuit of the paper folding device according to the first embodiment of the present invention. FIG. 16 is a schematic configuration diagram of a separation mechanism that separates the sandwiching members of the paper folding device according to the second embodiment of the present invention. FIG. 17 is an explanatory view showing an example of the operation of the separation mechanism of FIG. 16, wherein (a) shows a state in which the press units are separated from each other, and (b) shows that the press units are close to each other. It is a figure which shows a state. FIG. 18 is a flowchart showing an example of the control of the folding mechanism by the control circuit of the paper folding device according to the second embodiment of the present invention. FIG. 19 is a flowchart showing an example of the control of the folding mechanism by the control circuit of the paper folding device according to the third embodiment of the present invention.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. Note that similar components are included in the following embodiments. Therefore, below, about the same component, a common code | symbol is attached | subjected and the overlapping description is abbreviate | omitted.

(First embodiment)
<Path of paper>
FIG. 1 is an explanatory diagram showing a schematic configuration of a sheet post-processing apparatus 1 as a sheet folding apparatus according to the first embodiment. As shown in FIG. 1, in the sheet post-processing apparatus 1, an introduction path Pt 1 for receiving a sheet S as an image-formed sheet discharged from the image forming apparatus 2 and a sheet S are stacked on a sheet discharge tray 22. A transport path Pt2 for performing stapling on the sheet S, a transport path Pt4 for transporting the sheet S or the sheet bundle B (see FIGS. 2 and 3) from the transport path Pt3 to the folding mechanism 4. , Is provided.

<Introduction of paper>
An inlet roller 10 and an inlet sensor 13 are arranged in the introduction path Pt1. The entrance sensor 13 detects that the sheet S has been carried into the sheet post-processing apparatus 1. A perforation forming mechanism 3 for forming perforations in the sheet S is disposed downstream of the entrance roller 10, and conveyance rollers 11 and 12 are disposed downstream thereof. The sheet S is conveyed to the conveyance path Pt3 through these.

<Proof discharge>
The conveyance path Pt <b> 2 is a path for conveying the sheet S to the paper discharge tray 22. The sheet S whose traveling direction has been changed by the branching claw 20 from the introduction path Pt1 is conveyed to the sheet discharge tray 22 by the discharge roller 21.

<Shift, stack>
In the conveyance path Pt3, paper discharge rollers 31, 33, a paper discharge sensor 35, and the like are arranged. In the sort mode, the transport roller 12 having a shift mechanism (not shown) moves a certain amount in the direction perpendicular to the transport direction during transport of the sheet S by a drive mechanism including a transport roller drive motor 403 (see FIG. 13). As a result, the sheet S is shifted by a certain amount, discharged to the discharge tray 32 by the discharge rollers 33, and sequentially stacked. At the discharge port to the discharge tray 32, the sheet S as a sheet or the sheet bundle B as a sheet is sandwiched and discharged by a discharge roller 33 and a driven roller (discharge roller) 31. That is, the closed state in which the sheet S or the sheet bundle B can be pinched and discharged and the open state in which the sheet S or the sheet bundle B is discharged are selected by the contact / separation operation of the discharge guide 31a including the driven roller 31 with respect to the discharge roller 33. Alternatively, after the shifting operation of the sheet bundle B is completed, the sheet S or the sheet bundle B is pinched and discharged.

<Up-down movement of shift tray>
A filler 34 is provided near the upper portion of the paper discharge port. The filler 34 is rotatably disposed near the center of the sheet S when stacked, and the tip of the filler 34 is in contact with the upper surface of the sheet S. Near the base of the filler 34, there is an upper surface detection sensor (not shown) that detects the height position of the tip of the filler 34, thereby detecting the paper surface height of the stacked sheets S. When the upper surface detection sensor is turned on as the height of the sheet S increases due to an increase in the number of sheets deposited on the paper discharge tray 32, the CPU 401 (see FIG. 14 and the like) serving as a control unit drives the paper discharge tray 32 up and down. A mechanism (not shown) is controlled to lower the discharge tray 32. When the paper discharge tray 32 is lowered and the upper surface detection sensor is turned off, the CPU 401 stops the paper discharge tray 32 from being lowered. When this operation is repeated and the discharge tray 32 reaches the specified tray full height, a stop signal is sent from the sheet post-processing device 1 to the image forming device 2, and the image forming operation in the image forming device 2 is stopped.

<Stapling process>
A staple tray 36 and a hitting roller 30 are disposed on the transport path Pt3. At the end position of the transport path Pt3, a stapler 41 divided by a driver and a clincher that advance and retreat in a direction orthogonal to the paper surface is disposed. Further, jogger fences 37 and 38 that align the sheets S on the staple tray 36 by moving back and forth in a direction orthogonal to the paper surface are provided on the transport path Pt3. The sheet S conveyed to the conveyance path Pt3 is discharged onto the staple tray 36, and the position in the width direction is aligned by the jogger fences 37 and 38. Further, the hitting roller 30 switches back in the direction of the stapler 41 by performing a pendulum motion and contacting the upper surface of the sheet S. Thereby, the rear end of the sheet S is abutted against the reference fences 39 and 40, and the vertical position of the sheet bundle B is aligned.

  In the edge binding mode, the stapler 41 moves in a direction perpendicular to the paper surface and staples the appropriate position at the lower edge of the sheet bundle B, whereby the sheet bundle B that is abutted against and aligned with the reference fences 39 and 40 is bound. Then, the paper is discharged onto the paper discharge tray 32 by the paper discharge rollers 31 and 33 being sandwiched.

  On the other hand, in the saddle stitching mode, after the alignment of the sheet S (sheet bundle B) is completed, the rear end of the sheet bundle B is clamped by the clamp movable fences 120 and 121. The reference fences 39 and 40 are retracted outside in the width direction of the sheet bundle B so as not to hinder the conveyance of the sheet bundle B. The clamp movable fences 120 and 121 are attached to the clamp longitudinal axis 106 arranged outside the side plate of the housing, and move in the vertical direction and in the horizontal direction along the curved conveyance path Pt4. The clamp movable fences 120 and 121 are moved in the vertical direction by the clamp vertical axis 106, and are moved in the horizontal direction along the guide rail 110 on the side plate that is the same locus as the transport path Pt4. It is transported along the transport path Pt4. The sheet bundle B sandwiched at the rear end is conveyed along the guide rail 110 to a predetermined position corresponding to the sheet size, and is stapled at a predetermined position in the center in the longitudinal direction of the sheet bundle B. Here, the predetermined position corresponding to the sheet size is a position sent by a predetermined pulse from the clamp movable fence home position sensor 49.

<Bending process>
The sheet S or the sheet bundle B is further conveyed downward by the clamp movable fences 120 and 121 and introduced into the bending mechanism 4. The clamp movable fences 120 and 121 are stopped at a position where the longitudinal center portion of the sheet S or the sheet bundle B faces the blade 203 as a pushing member. Thereafter, a folding step of the sheet S or the sheet bundle B is performed. The position Pb (see FIGS. 2, 3 and the like) where the sheet S or the sheet bundle B is stopped is detected by the position sensor 50, for example, and a predetermined distance corresponding to the sheet size is conveyed. It can be a position sent by a drive mechanism including a roller drive motor 403 and the like. The blade 203 moves from the right to the left in FIG. 1 and pushes the central portion in the longitudinal direction of the sheet S or the sheet bundle B stopped at the position Pb between the pair of conveying rollers 206 and 207 and introduces it into the press unit 5. To do.

  Next, the conveyance rollers 206 and 207 rotate to convey the sheet S or the sheet bundle B pushed into the gap between them into the press unit 5 while bending. At this time, the amount by which the folded sheet S or sheet bundle B is pushed into the pressing unit 5, that is, the amount by which the folded sheet S or sheet bundle B is conveyed by the conveying rollers 206 and 207 is the number of sheets S or sheet bundle B. And variable by thickness. Specifically, for example, the conveyance roller drive motor 403 and the like are included from the position where the folding leading edge detection sensor 300 (see FIG. 10) detects the folding leading edge Bt (see FIGS. 9 and 11) of the sheet S or the sheet bundle B. The sheet S or the sheet bundle B is conveyed to the position Pv (see FIG. 10) by rotating the conveying rollers 206 and 207 by a predetermined number of times (angle) by the driving mechanism.

  Then, the sheet S or the sheet bundle B introduced into the pressing unit 5 and stopped at the position Pv (see FIG. 10) is pressed from above and below by pressing plates 219 and 220 as sandwiching members. The pressed sheet S or sheet bundle B is discharged onto the saddle stitching tray 62 by the conveying rollers 206 and 207 and the discharge roller 58.

  The sheet S or the sheet bundle B discharged to the saddle stitching tray 62 is pressed by a sheet pressing roller 61 attached to the sheet pressing 60. Thereby, it is suppressed that the folded sheet S or the sheet bundle B expands and the next sheet S or the sheet bundle B becomes difficult to be discharged. The perforation forming mechanism 3 and the bending mechanism 4 are detachably attached to the paper post-processing apparatus 1. In the paper post-processing apparatus 1, the functions of the punch forming mechanism 3 and the folding mechanism 4 can be provided according to the needs of the user.

<Configuration of bending mechanism>
FIG. 2 is a perspective view of the bending mechanism 4, and FIG. 3 is a side view of the bending mechanism 4. The bending mechanism 4 includes a press plate drive cam 201, a blade drive cam 202, a blade 203, a blade support bar 204, and a side plate 205. When the blade drive cam 202 rotates, the blade support bar 204 moves horizontally along the groove 202a provided in the blade drive cam 202, and the blade 203 moves in the X direction in FIGS. The center part in the longitudinal direction of the bundle B is pushed into the press part 5.

  4 is a view showing a state in which a part of the bending mechanism 4 of FIG. 2 is partially removed, and FIG. 5 is a side view of FIG. The press unit 5 presses the sheet S or the sheet bundle B introduced into the press unit 5 by the blade 203. The press unit 5 includes conveying rollers 206 and 207, a moving plate 208, press guide rollers 211 and 212, and press pressure releasing cams 209 and 210. The sheet S or the sheet bundle B introduced between the pair of conveying rollers 206 and 207 by the blade 203 is folded by a folding leading end detection sensor 300 (see FIG. 10) (not shown in FIG. 5) (see FIGS. 9 and 11). Until it is detected by the transport rollers 206 and 207. Further, the sheet S or the sheet bundle B is pressed by press plates 219 and 220 (see FIGS. 1 and 8 to 10) as sandwiching members in the press unit 5 by the rotation of the conveying rollers 206 and 207. It is transported to a position Pv (see FIG. 10). The sheet S or the sheet bundle B is bent deeper by being conveyed into the press unit 5 while being sandwiched between the pair of conveying rollers 206 and 207 as described above. Note that the conveyance amount (movement amount) of the sheet S or the sheet bundle B by the conveyance rollers 206 and 207 is controlled by a CPU 401 (see FIG. 13) as a control unit. Further, in the present embodiment, the moving plate 208 is configured to be movable in the left-right direction in FIG. 5, and the press guide rollers 211 and 212 and the press pressure releasing cams 209 and 210 connected to the moving plate 208. Is configured to be movable.

  FIG. 6 is a perspective view showing a state in which the moving plate 208 is further removed from the bending mechanism 4 shown in FIG. FIG. 7 is a side view of the VII portion of FIGS. A pressing force is applied to the upper left and right ends of the upper press unit 217 and the lower left and right ends of the lower press unit 218 by a spring (not shown), and the upper press unit 217 and lower The pressing units 218 are urged so as to be close to each other in the vertical direction of FIGS. In the standby state, the upper press unit 217 and the lower press unit 218 are moved in the vertical direction in FIGS. 6 and 7 by the press pressure release cams 209 and 210 provided inside the moving plate 208 (see FIGS. 4 and 5). They are separated from each other. In this standby state, the sheet S or the sheet bundle B can be introduced into the press unit 5.

  When the moving plate 208 moves in the X direction in FIG. 7, the press pressure release cams 209 and 210 connected to the moving plate 208 move, and the rollers 213 and 215 of the upper press unit 217 and the press unit 218 of the lower side move. The rollers 214 and 216 are moved in the A direction and the B direction in FIG. 7 by the inclined surfaces of the press release cams 209 and 210, respectively, so that the bent portion of the sheet S or the sheet bundle B is moved to the press plate 219, 220 (see FIGS. 1, 8 to 10 etc.).

  FIG. 8 is a perspective view showing an internal configuration of the press unit 5. FIG. 9 is a side view of FIG. Inside the upper and lower press units 217 and 218, press plates 219 and 220 as sandwiching members are connected, respectively. As the press pressure release cams 209 and 210 move, the press plate 219 moves in the direction A in FIG. 9 and the press plate 220 moves in FIG. 9 in conjunction with the upper and lower press units 217 and 218, respectively. By moving in the B direction, the sheet S or the sheet bundle B is sandwiched between the press plates 219 and 220 and pressed. The press guide rollers 211 and 212 connected to the moving plate 208 move on the press plates 219 and 220 in conjunction with the movement of the moving plate 208 in the X direction in FIG. Of the pressing plates 219 and 220 that can be rotated by grooves (221, 222, 223, and 224 in FIG. 7) toward the folding tip Bt (see FIGS. 9 and 11) of the sheet S or the sheet bundle B. Then, pinching and pressing are performed.

  FIG. 10 is a side view showing a part of the press part 5 in a simplified manner. A folding tip detection sensor 300 is arranged between the conveying rollers 206 and 207 for introducing the sheet S or the sheet bundle B (see FIG. 9) (not shown in FIG. 10) into the press unit 5 and the press plates 219 and 220. Yes. 10, P0 is the position (reference position) of the folded tip detection sensor 300, and P1 is the rightmost position of the pressable section Smax that can be pressed by the pair of curved press plates 219 and 220 (most at the reference position P0). (Close position), P3 is the leftmost position (position farthest from the reference position P0), P2 is an intermediate position between the positions P1 and P3, and Pv is the leftmost position (reference position P0) of the press section Sv. The farthest position). In FIG. 10, L0 is the distance from the reference position P0 to the rightmost position P1, Lv is the length of the press section Sv, and Lmax is the length of the pressable section Smax.

  The curved press plates 219 and 220 are driven by a press motor 404 (see FIG. 13) not shown in FIG. When pressing is performed in all the pressable sections Smax, the press plates 219 and 220 are first arranged at positions indicated by solid lines and press the sheet S or the sheet bundle B. Thereafter, the press plates 219 and 220 gradually move from the position indicated by the solid line to the state indicated by the alternate long and short dash line via the state indicated by the broken line. Move gradually from left to right.

  When the press process described above is completed, the press motor 404 is driven to carry out the sheet S or the sheet bundle B after the press process and the next sheet S or the sheet bundle B, and the press plates 219 and 220 are moved. Then, the press pressure releasing cams 209 and 210 are driven, and the upper and lower press plates 219 and 220 are separated from each other.

  And in this embodiment, press area Sv (length Lv) can be changed arbitrarily. That is, in this embodiment, for example, when the press section Sv is shorter than the pressable section Smax (Lv <Lmax), the press plates 219 and 220 are moved from the position P1 to the intermediate position Pv before the position P3, After the sheet S or the sheet bundle B is pressed in the press section Sv and the press plates 219 and 220 are returned from the position Pv to the position P1, they are separated from each other in the vertical direction. The press section Sv is set within the range of the pressable section Smax.

  In the present embodiment, the press section Sv by the pair of press plates 219 and 220 is changed according to at least one of the number of sheets S or the sheet bundle B and the thickness. FIG. 11 is an explanatory diagram of an example of setting the length Lv of the press section Sv according to the number of sheets B, and FIG. 12 is the number N of sheets S or sheet bundles B for each thickness of the sheet S and the press section Sv. It is a figure which shows an example of correlation with length Lv.

  As shown in FIG. 12, for example, the length Lv of the press section Sv is set so as to increase linearly (proportional) as the number N of sheets S increases and to increase as the thickness increases. Is done. The length Lv is experimentally obtained in advance, and is increased to a value that increases depending on the thickness of the sheet S or the number N of sheets, for example, according to the bulge or distance of the bent portion that changes depending on the “stiffness” of the sheet S. A value with a margin added. In FIG. 12, the correlation between the number of sheets S and the length Lv of the press section Sv is set in three sections according to the thickness of the sheet S. The thickness section is, for example, four sections. It is also possible to increase or decrease the number of sections, for example, by dividing into two sections. When the number of sections is increased, the application range can be expanded to a sheet having a large thickness, or the accuracy of the length Lv with respect to the thickness of the sheet S can be further improved to improve the processing efficiency. The effect that it can raise is acquired.

<Configuration of control circuit>
FIG. 13 is a block diagram showing a part of the control circuit 400 of the sheet post-processing apparatus 1, and FIG. 14 is a block diagram of a CPU (Central Processing Unit) 401 included in the control circuit 400. As shown in FIG. 13, the sheet post-processing apparatus 1 includes a CPU 401, a ROM (Read Only Memory) 402a, a RAM (Random Access Memory) 402b, an NVRAM (Non Volatile Ram) 402c, a sensor controller 402d, and motor controllers 402e and 402f. And a communication interface 402g. These constituent elements are electrically connected to each other via a bus line 402h such as an address bus or a data bus.

  The CPU 401 controls the sheet post-processing apparatus 1 by executing various computer-readable programs stored in the ROM 402a or the like. The ROM 402a stores various data executed by the CPU 401, various programs (BIOS (Basic Input Output System) program, application program, device driver program, etc.) and the like. The RAM 402b temporarily stores data and programs when the CPU 401 executes various programs. Further, the NVRAM 402c can store various data such as a key (data) described later even when the power is turned off.

  In the present embodiment, the program acquires a module for obtaining the number of sheets S to be pressed by the press unit 5, a module for obtaining the thickness of the sheet S, a module for obtaining a classification of the thickness of the sheet S, and upper and lower presses. A module for calculating the length Lv of the press section Sv by the plates 219 and 220, a module for calculating the transport length of the sheet bundle B by the transport rollers 206 and 207, and a detection signal from the folding tip detection sensor 300 as a reference position signal. Modules for controlling the operations of the press plates 219 and 220, and the like. Therefore, as shown in FIG. 14, the CPU 401 of the sheet post-processing apparatus 1 has a sheet number acquisition unit 401a, a sheet thickness acquisition unit 401b, a sheet thickness category acquisition unit 401c, a press section length calculation unit 401d, and a conveyance length. It functions as a height calculation unit 401e, a reference position signal acquisition unit 401g, a press control unit 401h, and the like. In the present embodiment, the press control unit 401h corresponds to a pinching control unit.

<Control of bending mechanism>
FIG. 15 is a flowchart showing an example of control of the bending mechanism 4 by the control circuit 400. First, the CPU 401 acquires whether or not to execute the bending process from a signal such as a post-processing execution command received from the image forming apparatus 2 (step S1). When the bending process is performed (Yes in Step S1), the process proceeds to Step S2, and when it is not performed (No in Step S1), the process waits as it is.

  When the bending process is performed (Yes in step S1), the CPU 401 functions as the sheet number acquisition unit 401a and acquires the number of sheets S from the signal received from the image forming apparatus 2 (step S2). Next, the CPU 401 acquires the thickness of the sheet S from the signal received from the image forming apparatus 2 (step S3). The image forming apparatus 2 is equipped with a sheet thickness sensor (not shown) that detects the thickness W of the sheet S.

  Next, the CPU 401 functions as the sheet thickness category acquisition unit 401c, and acquires the thickness category by comparing the acquired thickness W of the sheet S with the threshold values W1 and W2 of the category (step S4). ~ S8). When the thickness W is smaller than the threshold value W1 (Yes in step S4), the thickness division is set to the thinnest “section 1” (step S6). When the thickness W is larger than the threshold value W2 (Yes in step S5), the thickness division is set to the thickest “section 3” (step S7). In the case of No in step S5, that is, when the thickness W is not less than the threshold value W1 and not more than the threshold value W2, the thickness category is set to “class 2” (step S8).

  The threshold values W1 and W2 are set in advance based on experiments or the like. Specifically, for example, when the capacity of the sheet S for the sheet S of the sheet post-processing apparatus 1 is 42 kg to 180 kg, 42 kg to 63 kg (a typical high quality paper is converted into a thickness per sheet) In the case where a sheet up to about 0.06 to 0.08 mm) is set as thin paper (section 1), the threshold value W1 is set to the upper limit of 0.08 mm. In addition, in this example, the kilogram continuous capacity is 42 kg to 63 kg, but may be another value such as 42 kg to 55 kg. The continuous quantity is the weight per 1000 sheets of 46 sheets of paper. Further, in the case where the capacity of the sheet S of the sheet post-processing apparatus 1 is from 42 kg to 180 kg, 90 kg to 180 kg (0.13 to 0 for general high quality paper when converted to the thickness of one sheet) When a sheet up to about 23 mm is set as a thick sheet (Category 3), the threshold W2 is set to a lower limit of 0.13 mm. In addition, in this example, the kilogram continuous capacity corresponding force was 90 kg to 180 kg, but may be another value such as 110 kg to 180 kg. As an example, the threshold values W1 and W2 are stored in a storage unit such as the NVRAM 402c, and the CPU 401 refers to the threshold values W1 and W2 stored in the storage unit and acquires the thickness category.

  Next, the CPU 401 functions as the press section length calculation unit 401d, refers to the table stored in the NVRAM 402c, and determines the thickness classification acquired in steps S6 to S8 and the number of sheets S acquired in step S2. The length Lv of the press section Sv corresponding to is calculated (step S9). In this step S9, the press section length calculation unit 401d performs, for example, a step from a plurality of representative values stored in the NVRAM 402c (values at points plotted in FIG. 12) by a technique such as interpolation or extrapolation. The length Lv of the press section Sv corresponding to the thickness classification acquired in S6 to S8 and the number of sheets S acquired in step S2 is calculated. In addition, the press section length calculation unit 401d inputs the number of sheets S acquired in step S2 to a preset function (for example, a linear function, a mathematical expression, etc.), thereby the length Lv of the press section Sv. Can be calculated. In this case, the function can be set for each thickness section, or the function coefficient can be changed for each thickness section.

  Next, the CPU 401 acquires a distance L0 from the folding leading edge detection sensor 300 corresponding to the sheet post-processing apparatus 1 to the rightmost position P1 from a storage unit such as the NVRAM 402c (step S10). This distance L is set according to the paper post-processing apparatus 1, the folding mechanism 4, and the like.

  Next, the CPU 401 operates as the conveyance control unit 401f and drives the conveyance roller driving motor 403 (see FIG. 13) to rotate the pair of conveyance rollers 206 and 207 so that the sheet S or the sheet bundle B can be conveyed. In addition, the sheet S or the sheet bundle B pushed between the pair of conveying rollers 206 and 207 is conveyed to the inside of the press unit 5 (step S11). Then, when the CPU 401 operates as the reference position signal acquisition unit 401g and receives a reference position signal as a detection signal from the folding leading edge detection sensor 300, the conveyance control unit 401f starts to receive the sheet S or the sheet S from the time when the reference position signal is received. When the sheet bundle B is conveyed by a predetermined distance, the conveyance roller drive motor 403 is stopped. That is, the conveyance control unit 401f conveys the sheet S or the sheet bundle B by a predetermined distance after being detected by the folding leading edge detection sensor 300 (step S12). The predetermined distance in step S12 is Lv + L0. As a result, the sheet S or the sheet bundle B is conveyed to a position where it is pressed by the press plates 219 and 220.

  Next, the CPU 401 operates as the press control unit 401h, drives the press motor 404 as necessary, and positions the press plates 219 and 220 as sandwiching members at the position P1 in FIG. 10 (step S13).

  Next, the CPU 401 operates as the press control unit 401h, drives the press motor 404, and moves the press plates 219 and 220 as sandwiching members toward the position P3 side by the length Lv of the press section Sv, The sheet S or the sheet bundle B is pressed in the X direction (see FIG. 10) in the pressing section Sv (step S14).

  Next, the CPU 401 operates as the press control unit 401h, drives the press motor 404 in the direction reverse to the step S14, and presses the press plates 219 and 220 as sandwiching members toward the position P1 side in the press section. The sheet is moved by the length Lv of Sv, and the sheet S or the sheet bundle B is pressed in the direction opposite to the X direction in the pressing section Sv (step S15).

  Next, the CPU 401 operates as the press control unit 401h, further drives the press motor 404 in the direction opposite to that in step S14, and separates the press plates 219 and 220 as sandwiching members from each other (step S16). . Then, the CPU 401 controls each part of the sheet post-processing apparatus 1 to discharge (discharge) the pressed sheet S or sheet bundle B onto the saddle stitching tray 62 (step S17).

  As described above, in the present embodiment, the press control unit 401h serving as the sandwiching control unit has the press plate 219 serving as the sandwiching member according to at least one of the number of sheets S and the thickness thereof (both in the present embodiment). 220 movement (movement position, movement amount, etc.) is variably controlled. Further, in the present embodiment, the conveyance control unit 401f performs the sheet S or the sheet by the conveyance rollers 206 and 207 as a pair of rollers according to at least one of the number and the thickness of the sheets S (both in the present embodiment). The conveyance (conveyance position, conveyance amount, etc.) of the bundle B is variably controlled. In this embodiment, the length of the sandwiching processing section of the sheet S or the sheet bundle B can be variably set more appropriately according to the specifications of the sheet S or the sheet bundle B by these controls. Therefore, according to the present embodiment, useless press operations can be reduced. Therefore, the throughput of the bending process can be improved and the number of bending processes per unit time can be increased.

  As an example, the maximum press length Lmax supported by the paper post-processing apparatus 1 is 15 mm, the press length Lv for a two-fold / thick paper sheet bundle B is 0.5 mm, and the press plates 219 and 220 are 1 mm. Assuming that the time required to press the distance is 0.05 s (seconds), the time required to press the double-folded / thick paper bundle is when the maximum length Lmax is pressed without using the above-described control. Is 15 mm × 0.05 s × 2 (the reciprocating motion of the press plates 219 and 220) = 1.5 s, and when the length Lv is pressed by the above-described control, 0.5 mm × 0.05 s × 2 (press The reciprocal of the plate) = 0.5 s. That is, according to this embodiment, the time required for pressing can be shortened by 1.5−0.5 = 1 s. It will be understood that this time difference becomes more prominent as the number of processes increases.

  It should be noted that the length of the sandwiching section can be varied only by the amount of movement of the press plates 219 and 220 as the sandwiching members, and can be varied only by the transport amount of the sheet S or the sheet bundle B by the transport rollers 206 and 207. You can also. In the present embodiment, the sandwiching process can be executed more efficiently by controlling both of them. Further, the CPU 401 as the control unit may execute variable control of movement of the press plates 219 and 220 or conveyance of the sheet S or the sheet bundle B according to only one of the number and thickness of the sheets S.

  Furthermore, in this embodiment, at least a part of at least one of the press plates 219 and 220 as the sandwiching member is configured as an elastic body such as an elastomer, a synthetic resin, or a flexible metal member. Is preferred. Thereby, it can suppress that the sound and vibration by press plate 219,220 contact | abutting or separating at the time of the start or completion | finish of a press, etc. arise. When the elastic body is configured, for example, as an elastomer, the elastic body is provided on the contact surface of the press plates 219 and 220, or the supported portion (base end portion) and the contact portion (tip end portion) of the press plates 219 and 220. And an elastic body can be interposed between them.

(Second Embodiment)
<Separation mechanism>
FIG. 16 is a schematic configuration diagram of a separation mechanism 310 that separates the press plates 219 and 220 as sandwiching members from each other. 17A and 17B are views showing the operation of the separation mechanism 310, where FIG. 17A shows a state where the press units 217 and 218 are separated from each other, and FIG. 17B shows a state where the press units 217 and 218 are close to each other. It is a figure which shows the state which carried out. The sheet post-processing apparatus 1 according to the present embodiment includes a separation mechanism 310 that vertically separates or closes the press units 217 and 218 regardless of the positions of the press plates 219 and 220 as sandwiching members. The separation mechanism 310 includes a separation mechanism drive motor 301, a worm 302 attached to the output shaft of the separation mechanism drive motor 301, a press unit separation plate 304, a press unit separation member 306 provided inside the press unit separation plate 304, 307, a gear 303 and the like meshed with a worm 302 and a rack 305 provided on the press unit separation plate 304. When the separation mechanism drive motor 301 is rotated forward (rotated in the direction of the arrow) by the separation mechanism 310, the worm 302 is rotated, and the gear 303 engaged with the worm 302 is rotated counterclockwise in the drawing. Furthermore, the press unit separation plate 304 is moved in the left direction in the figure by the rack 305 meshing with the gear 303. When the separation mechanism drive motor 301 is reversed, the press unit separation plate 304 moves rightward in the drawing.

  As shown in FIGS. 17A and 17B, when the press unit separation members 306 and 307 are moved rightward by driving the separation mechanism drive motor 301, the press unit separation members 306 and 307 are provided. The rollers 213, 214, 215, 216 provided on the press units 217, 218 ride on the press unit separation members 306, 307 by the inclination, and the press units 217, 218 are separated from each other in the vertical direction. On the contrary, when the press unit separation members 306 and 307 are moved leftward by driving the separation mechanism drive motor 301, the press units 217 and 218 are moved in the vertical direction by an urging force by an urging mechanism such as a spring (not shown). Close to each other. That is, in the present embodiment, the separation mechanism 310 corresponds to a proximity mechanism.

<Control of bending mechanism>
FIG. 18 is a flowchart illustrating an example of control of the bending mechanism 4 by the control circuit 400 according to the present embodiment. In FIG. 18, the same processes as those in FIG. 15 are given the same reference numerals as those in FIG. In the present embodiment, as indicated by a broken line in FIG. 13, the control circuit 400 includes a motor controller 402 i for the separation mechanism drive motor 301. Further, the CPU 401 includes a separation control unit 401i indicated by a broken line in FIG. 14 (the determination unit 401j is not included). The CPU 401 operates as a separation control unit 401 i by a module that controls the operation of the separation mechanism drive motor 301 included in a program that operates the CPU 401.

  Steps S1 to S12 are the same as those in the first embodiment (FIG. 15), and a duplicate description is omitted. In step S13a after step S12, in the present embodiment, the CPU 401 operates as the separation control unit 401i, controls the separation mechanism drive motor 301, and brings the upper and lower press plates 219 and 220 closer to each other to form the sheet. S or the sheet bundle B is pressed (step S13a). In step S13a, the position where the sheet S or the sheet bundle B is sandwiched is the position P1 in FIG.

  Next, the CPU 401 operates as the press control unit 401h, drives the press motor 404, and pushes the press plates 219 and 220 as sandwiching members toward the left side of FIGS. 16 and 17 by the length Lv of the press section Sv. The sheet S or the sheet bundle B is pressed in the X direction in the pressing section Sv (step S14).

  Next, the CPU 401 operates as the separation control unit 401i, controls the separation mechanism drive motor 301, and separates the upper and lower press plates 219 and 220 from each other (step S16a). In step S16a, the press plates 219 and 220 can be separated from each other regardless of the length Lv of the press section Sv, that is, regardless of the position of the press plates 219 and 220.

  Next, the CPU 401 controls each part of the sheet post-processing apparatus 1 and discharges the pressed sheet S or sheet bundle B onto the saddle stitching tray 62 (step S17).

  Next, the CPU 401 operates as the press control unit 401h, drives the press motor 404 in the direction reverse to the step S14, and presses the press plates 219 and 220 as sandwiching members toward the position P1 side in the press section. Move by the length Lv of Sv (return, step S15a). However, in this step S15a, the press plates 219 and 220 are separated from each other, and the press on the sheet S or the sheet bundle B by the press plates 219 and 220 is not executed. In the present embodiment, the position P1 can be said to be a home position.

  According to the sheet post-processing apparatus 1 according to the second embodiment described above, after the press process on the sheet S or the sheet bundle B is completed, the press plates 219 and 220 are quickly separated from each other, and the sheet S or the sheet bundle B is immediately separated. Can be discharged. Therefore, the processing efficiency of the bending process can be further improved.

(Third embodiment)
<Control of bending mechanism>
FIG. 19 is a flowchart illustrating an example of control of the bending mechanism 4 by the control circuit 400 according to the present embodiment. 19, the same processes as those in FIGS. 15 and 18 are given the same reference numerals as those in FIGS. In this embodiment as well, as in the second embodiment, the control circuit 400 includes a motor controller 402i for the separation mechanism drive motor 301, as indicated by a broken line in FIG. Further, the CPU 401 includes a determination unit 401j in addition to the separation control unit 401i indicated by a broken line in FIG. The CPU 401 operates as a separation control unit 401i by a module that controls the operation of the separation mechanism drive motor 301 included in the program that operates the CPU 401, and determines that the program is included in the program (details of determination will be described later) It operates as the determination unit 401j.

  Steps S1 to S10 are the same as those in the second embodiment (FIG. 18), and thus redundant description is omitted. In step S11a after step S10, in this embodiment, the CPU 401 acquires the current position Pc of the press plates 219 and 220 (step S11a). The current position Pc has the reference position P0 as the origin.

  Next, when the CPU 401 operates as the determination unit 401j and starts to move the press plates 219 and 220 as sandwiching members from the current position (hereinafter referred to as Pc), the movement amount of the press plates 219 and 220 is sufficient. Determine whether or not. That is, the determination unit 401j first obtains the remaining distance (Lmax−Lc) from the current position Pc (distance from the position P1: Lc) to the position Pmax, and the remaining distance (Lmax−Lc) in step S9. The calculated length Lv of the press section Sv is compared (step S11b). Here, when the remaining distance (Lmax−Lc) is equal to or longer than the length Lv of the press section Sv (Yes in step S11b), the press is started from the current position Pc and executed toward the side farther from the reference position P0. In this case, the press for the length Lv of the press section Sv calculated in step S9 can be executed. Therefore, in this case, the CPU 401 operates as the conveyance control unit 401f as in step S11 of FIGS. 15 and 18, and drives the conveyance roller drive motor 403 (see FIG. 13) to move the pair of conveyance rollers 206 and 207. The sheet S or the sheet bundle B is rotated so that the sheet S or the sheet bundle B can be conveyed, and the sheet S or the sheet bundle B introduced between the pair of conveying rollers 206 and 207 is conveyed to the inside of the press unit 5 (step S11). Then, when the CPU 401 operates as the reference position signal acquisition unit 401g and receives a reference position signal as a detection signal from the folding leading edge detection sensor 300, the conveyance control unit 401f starts to receive the sheet S or the sheet S from the time when the reference position signal is received. When the sheet bundle B is conveyed by a predetermined distance, the conveyance roller drive motor 403 is stopped. That is, the conveyance control unit 401f conveys the sheet S or the sheet bundle B by a predetermined distance after being detected by the folding leading edge detection sensor 300 (step S12a). The predetermined distance in step S12a is Lv + Lc + L0. As a result, the sheet S or the sheet bundle B is conveyed to a position where it is pressed by the press plates 219 and 220.

  On the other hand, if No in step S11b, that is, if the remaining distance (Lmax−Lc) is smaller than the length Lv of the press section Sv, pressing is started from the current position Pc and executed toward the side farther from the reference position P0. In this case, the remaining distance (Lmax−Lc) is insufficient, and the press for the length Lv of the press section Sv calculated in step S9 cannot be executed. Therefore, in this case, the CPU 401 operates as the press control unit 401h, and moves the press plates 219 and 220 to the position P1 (see FIG. 10) (step S11c). The distance Lc corresponding to Pc is set to 0 (zero) (step S11d). Thereafter, Steps S11 and 12a are executed.

  Further, Steps S13a, S14, S16a, S17, and S15a after Step S12a are the same as those in the second embodiment (FIG. 18), and thus redundant description is omitted.

  When step S17 is completed, the length from the reference position P0 to the position where the press is completed is Lc + Lv. The CPU 401 stores this length in the NVRAM 402c as a storage unit as a length Lc from the reference position P0 to the current position Pc used in the next press process (step S18). Thereby, in the press process for the next sheet S or sheet bundle B, if the press can be executed from the position of the press plates 219 and 220 when the press is completed, the press is executed. Therefore, according to the present embodiment, it is possible to increase the number of cases where the press is performed without returning the press plates 219 and 220, so that the throughput of the bending process can be further improved and the folding per unit time can be improved. The number of song processing can be further increased. Further, energy consumption can be reduced as much as the drive frequency of the press motor 404 can be reduced.

  The preferred embodiments of the present invention have been described above. However, the present invention is not limited to the above-described embodiments, and various modifications can be made. For example, the folding mechanism can be provided at a part of the rear stage of the image forming apparatus. Further, the configuration of other parts of the sheet post-processing apparatus can be changed as appropriate. The present invention can also be applied to a case where a sheet that is not stapled is bent. Further, the sandwiching member is not limited to the configuration of the above-described embodiment. For example, the sandwiching member may be configured as a pair of rollers that sandwich the sheet while moving along the sheet. In addition, for the nipping members that do not move along the sheet, the length of the nipping process section is changed by variably controlling the conveyance amount of the sheet according to at least one of the number of sheets and the thickness of the sheet. It is also possible to improve the efficiency of the sandwiching process by adjusting the time required. In addition, specifications (system, configuration, shape, material, number, arrangement, size, length, width, thickness, etc. of paper post-processing device, image forming device, pushing member, roller, sandwiching member, proximity mechanism, separation mechanism, etc. Etc.) can be implemented with appropriate changes.

  As described above, the present invention is useful for a sheet folding apparatus, a sheet post-processing apparatus or an image forming apparatus having a folding mechanism, and the like.

1. Paper post-processing device (an example of a paper folding device)
2. Image forming apparatus 203 ... Blade (an example of a pushing member)
206, 207 ... Conveying rollers (an example of rollers)
219, 220 ... Press plate (an example of a sandwiching member)
310 ... separation mechanism (an example of a proximity mechanism)
401... CPU (an example of a control unit)
401h: Press control unit (an example of a pinching control unit)
401f ... Conveyance control unit 401j ... Judgment unit S ... Sheet (an example of paper)
B ... Sheet bundle (an example of paper)

Claims (10)

A pair of sandwiching members that are opposed to each other along the overlapping direction of the overlapping portions of the folded sheets of paper and sandwich the stacked portions while moving along the overlapping portions ;
By variably controlling the amount of movement of the sandwiching member along the overlapped portion according to at least one of the number of sheets and the thickness of the sheet, the length of the sheet sandwiching processing section by the sandwiching member is variable. A control unit to control;
A paper folding device comprising: Paper folding device according to claim 1, further comprising a separation mechanism that the pair of pinching members to relatively apart the pair of gripping members in a state positioned in the middle in that movement section. A proximity mechanism for relatively approaching the pair of sandwiching members from a position relatively separated by the separation mechanism toward a position in the middle of the movement section;
The sheet bending device according to claim 2 , wherein the control unit starts movement of the pair of sandwiching members from the midway position. A pair of sandwiching members for sandwiching the folded paper;
A control unit that variably controls the length of the sheet nipping process section by the nipping member according to at least one of the number of sheets and the thickness of the sheet;
A separating mechanism that relatively separates the pair of sandwiching members in a state where the pair of sandwiching members are located in the middle of the moving section;
A proximity mechanism that relatively moves the pair of sandwiching members from a position relatively separated by the separation mechanism toward a position in the middle of the movement section;
With
The control unit starts the movement of the pair of sandwiching members from the midway position. The pair of sandwiching members sandwich the sheet while moving along the folded sheet,
5. The sheet folding device according to claim 4 , wherein the control unit variably controls a moving amount of the sandwiching member according to at least one of the number and thickness of the sheets. Paper folding device according to claim 1, 2, 3 or 5, characterized in that said pinching movement amount of incremental member relative number of the paper the greater the thickness of the sheet is large. A pair of rollers for conveying and folding the paper;
Wherein the control unit, any one of claims 1 to 6, wherein in response to at least one of the number and thickness of the sheet, characterized by variably controlling the conveyance amount of the sheet by the pair of rollers The paper folding device described in 1. Whether or not the movement amount of the pair of sandwiching members is sufficient when the movement of the pair of sandwiching members is started from the midway position based on at least one of the number and thickness of the sheets and the midway position Having a determination unit for determining
When the determination unit determines that the movement amount is sufficient, the control unit starts moving the pair of sandwiching members from the midway position,
The said control part moves the said clamping member from the said position in the middle when the said judgment part judges that the said movement amount is insufficient, The required movement amount is ensured, or Claim 3 characterized by the above-mentioned. paper folding device according to 4. Paper folding apparatus according to any one of claims 1-8, characterized in that at least one of the pair of gripping members has an elastic body. A pair of sandwiching members that are opposed to each other along the overlapping direction of the overlapping portions of the folded sheets of paper and sandwich the stacked portions while moving along the overlapping portions ;
By variably controlling the amount of movement of the sandwiching member along the overlapped portion according to at least one of the number of sheets and the thickness of the sheet, the length of the sheet sandwiching processing section by the sandwiching member is variable. A control unit to control;
An image forming apparatus comprising:

Images