JP2013075732A - Sheet folding device, image forming system, and sheet folding method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce a folding height of a sheet bundle, by preventing a swelling of the sheet bundle, while minimizing reduction in productivity.SOLUTION: This sheet folding device applies a folding processing to the sheet bundle PB, includes: carrier rollers 206 and 207 for carrying the folded sheet bundle PB; and an upper press plate 219 and a lower press plate 220 for sandwiching the sheet bundle PB carried by the carrier rollers 206 and 207 from both surface sides and pressing it while moving a sandwiching point to the downstream side from the upstream side in the sheet carrying direction. A fold line is formed in a folding end part W by butting the folding end part W of the sheet bundle PB projected from end surfaces E of the upper and lower press plates 219 and 220 against a butting surface 301a of a butting member 301 in a pressing process by the upper and lower press plates 219 and 220 and making the folding end part W enter into a clearance Z arranged between the butting surface 301a and the end surfaces E.

Description

  The present invention relates to a sheet folding device that performs a folding process on a sheet-like member (herein, simply referred to as “sheet”) such as paper, transfer paper, and an OHP sheet, the sheet folding device, a copying machine, and a printer. The present invention relates to an image forming system including an image forming apparatus such as a facsimile or a digital multi-function peripheral, and a sheet folding method executed by the sheet folding apparatus.

  In a so-called post-processing peripheral device that performs predetermined processing on a sheet discharged from an image forming apparatus such as a copying machine, a plurality of sheets are saddle-stitched by a staple (binding device), and then pressed by a press roller or a press plate. A technique of pressing and folding it in half (hereinafter referred to as “saddle stitch folding”) is known.

  In this technique, the folding plate is generally pressed against the folding position of the sheet bundle, and the folding position of the sheet bundle is pushed into the nip of the pair of folding rollers by the folding plate to make a crease.

  In such a sheet folding apparatus, after the crease is pressed and applied to the pair of folding rollers and then passed through the nip of the pair of folding rollers, the pressure applied to the nip is released, so that the fold may swell. This becomes more noticeable as the number of sheets increases. As the number of copies increases, the sheet bundle swells to the thickness of the sheet bundle itself as the number of copies increases. Becomes unstable because of the weighting. Then, when the stacked sheet bundle becomes unstable, and a further swollen sheet bundle is discharged from the sheet bundle, there is a case in which a stacked mountain collapses and a problem such as collapse from the discharge tray may occur. .

  Thus, for example, an invention described in Patent Document 1 is known as an apparatus that folds while suppressing such a bulge of a fold. In the invention described in Patent Document 1 (Japanese Patent Laid-Open No. 2010-64870), in order to further reduce the folding height of a sheet bundle with a simple configuration, the folding roller is rotated in the sheet discharge direction to perform the first folding process. Then, the folding roller is rotated in the reverse direction so that the sheet bundle on which one fold is formed is separated from the folding roller, and the folding plate is rotated again in the paper discharge direction at a position separated from the first fold by a predetermined width. The second fold line is formed by inserting it into the nip portion of the folding roller.

  However, as described in Japanese Patent Laid-Open No. 2004-260, productivity is reduced when the second folding is performed after the folding roller is reversed and the sheet bundle is returned after performing one folding. I cannot deny. That is, if a plurality of diffractions are performed, the productivity is naturally lowered.

  Therefore, the problem to be solved by the present invention is to minimize the decrease in productivity, prevent the sheet bundle from bulging, and reduce the folding height of the sheet bundle.

  In order to solve the above-described problems, the present invention provides a sheet folding device that performs a folding process on a sheet or a sheet bundle, and conveys the folded sheet or the sheet bundle, and is conveyed by the conveying unit. Further, the folding means for clamping the sheet or the sheet bundle from both sides and pressing while moving the clamping point from the upstream side to the downstream side in the sheet conveying direction, and the sheet or the sheet protruding from the folding means during the pressing process And a crease forming means that abuts the front end of the bundle against the abutment surface of the abutment member and creases the front end.

  According to the present invention, it is possible to minimize the decrease in productivity, prevent the sheet bundle from bulging, and reduce the folding height of the sheet bundle.

1 is a diagram illustrating a system configuration of an image forming system according to an embodiment of the present invention. It is a perspective view of the press folding part of the sheet folding apparatus in FIG. It is the front view which looked at the press folding part of FIG. 2 from the apparatus front side. FIG. 3 is a perspective view showing a state where a press plate driving cam, a folding blade driving cam, and a side plate in FIG. 2 are removed. It is the front view which looked at FIG. 4 from the apparatus front side. It is a perspective view which shows the state which removed the moving plate from FIG. It is the front view seen from the apparatus front side which expands and shows the dotted-line part H of FIG. It is a perspective view which shows the internal structure of the press unit of FIG. It is the front view which looked at FIG. 8 from the apparatus front side. It is a front view which shows the state at the time of the press folding start of the press folding part in Example 1. FIG. It is a front view which shows the state at the time of the press by the butting member of the press folding part in Example 1. FIG. It is a figure which shows the folding state of a sheet bundle at the time of shape | molding a folding front-end | tip part by the conventional method. It is a figure which shows a folding state at the time of shape | molding a folding front-end | tip part with the butting member in this embodiment. It is a block diagram which shows the control structure of the sheet | seat post-processing apparatus relevant to embodiment of this invention. 6 is a flowchart illustrating a sheet folding operation procedure according to the first exemplary embodiment. It is a figure which shows the detail and operation | movement of a press folding part provided with the butting member in Example 2. FIG. It is a figure which shows the detail and operation | movement of a press folding part provided with the butting member in Example 3. FIG. 10 is a flowchart illustrating a sheet folding operation procedure according to the third exemplary embodiment. 10 is a flowchart illustrating a sheet folding operation procedure according to the fourth exemplary embodiment. 10 is a flowchart illustrating a sheet folding operation procedure according to the fifth exemplary embodiment. It is a figure which shows the detail and operation | movement of a press folding part provided with the butting member in Example 6. FIG. 10 is a flowchart illustrating an operation procedure of sheet folding in Embodiment 6.

  The present invention is characterized in that when the sheet is folded by the folding means, the folded portion of the sheet is abutted against the abutting member to form a fold in a U-shape, thereby reducing the folding height.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a diagram showing a system configuration of an image forming system according to the present embodiment. The image forming system according to the present embodiment includes an image forming apparatus PR and a sheet post-processing apparatus 100 as a sheet processing apparatus installed at a subsequent stage of the image forming apparatus PR. The image forming apparatus PR includes, for example, an image forming unit (not shown) that forms an image by an electrophotographic process, and a paper feeding unit that supplies a sheet to the image forming unit. Information transmitted from a personal computer PC, information read by a scanner, It has a function of printing information or forming an image on a sheet of information stored in a hard disk in the image forming apparatus PR. The image forming unit is not an electrophotographic process, and a known image forming unit such as a droplet discharge type such as an ink jet or a thermal type is used. In FIG. 1, only the outer shape of the apparatus housing of the image forming apparatus PR on the sheet post-processing apparatus side is indicated by a one-dot chain line.

  In this embodiment, the sheet post-processing apparatus 100 is configured separately from the image forming apparatus PR, and the sheet post-processing apparatus 100 is connected to the subsequent stage of the image forming apparatus PR. It is also possible to form a single unit. Further, the image forming apparatus PR may be a copying machine or a digital multifunction machine having a combination of functions of a copying machine, a printer, a facsimile, and the like.

  The sheet post-processing apparatus 100 stacks the first transport path (entrance transport path) 1 that receives the image-formed sheet P discharged from the image forming apparatus PR and the sheet P on the discharge (proof) tray 22. The second conveyance path 2 for the sheet, the third conveyance path 3 for intermediately stacking the sheets P, and the sheet bundle PB in which the central portion of the sheet length is saddle-stitched in the third conveyance path 3 to the paper folding section. It has the 4th conveyance path 4 to convey.

  An entrance roller 10 and an entrance sensor 13 are arranged in the first transport path 1, and the entrance sensor 13 detects that a sheet has been carried into the sheet post-processing apparatus 100. A paper punching unit 101 is installed downstream of the entrance roller 10, and first and second transport rollers 11 and 12 are arranged in this order along the transport direction downstream of the entrance roller 10. The paper P is transported to the third transport path 3 by the transport rollers 11 and 12.

  The second transport path 2 is a path for transporting the sheet to the paper discharge tray 22 and branches upward from the first transport path 1, and a branching claw 20 is provided at the branch point. The sheet P whose direction of travel has been changed by the branching claw 20 from the first transport path 1 is transported from the first transport roller 11 to the discharge tray 22 via the discharge roller 21.

  A paper discharge driven roller 31, a paper discharge driving roller 33, and a paper discharge sensor 35 are arranged in the third transport path 3. In the sort mode, the second conveying roller 12 having a shift mechanism is moved by a certain amount in the direction perpendicular to the conveying direction during conveyance by driving means (not shown), so that the sheet P is shifted by a certain amount, and the discharge driving roller 33 As a result, the paper is discharged to the paper discharge tray 32 and sequentially stacked. The discharge port to the discharge tray 32 sandwiches the sheet P or the sheet bundle PB by the discharge drive roller 33 and the discharge driven roller 31 and discharges the sheet P or the sheet bundle PB by applying a conveying force. In this discharge operation, the sheet P or the sheet bundle PB is pinched by the contact / separation operation of the discharge guide 31a including the discharge driven roller 31 with respect to the discharge driving roller 33, and the discharge state is closed and the open state is not held. After the shift operation of the sheet P is completed, the discharge guide 31a is operated to hold the sheet P between the discharge driven roller 31 and the discharge driving roller 33, and thereby the sheet P is discharged. It is discharged to the tray 32.

  A filler 34 is provided in the vicinity of the upper part of the paper discharge port, and the base end side is freely rotatable so that the front end contacts the position near the center of the sheet P when the sheet P is stacked on the paper discharge tray 32. It is attached to the sheet post-processing apparatus 100. Near the base end of the filler 34, an upper surface detection sensor (not shown) that detects the height position of the tip of the filler 34 is provided, and detects the height of the stack sheet.

  When the upper surface detection sensor is turned on as the sheet height rises due to an increase in the number of sheets deposited on the paper discharge tray 32, a control unit (not shown) controls drive means (not shown) that moves the paper discharge tray 32 up and down. The paper discharge tray 32 is lowered. When the discharge tray 32 is lowered and the upper surface detection sensor is turned off, the lowering of the discharge tray 32 is stopped. This operation is repeated, and when the sheet discharge tray 32 reaches a specified tray full height, a stop signal is output from the sheet post-processing apparatus 100 to the image forming apparatus PR, and the image forming operation of the image forming apparatus PR is stopped.

  A staple tray 36 and a hitting roller 30 are disposed in the third conveyance path 3, and a stapler 41 divided by a driver and a clincher that advance and retreat in a direction orthogonal to the paper surface is disposed at the terminal position of the third conveyance path 3. Has been placed. Furthermore, jogger fences 37 and 38 for aligning sheets on the staple tray 36 by moving back and forth in a direction orthogonal to the paper surface are provided in front of the end position. The sheet conveyed to the third conveyance path 3 is discharged onto the staple tray 36 and aligned in the width direction by the jogger fences 37 and 38.

  Further, the hitting roller 30 performs a pendulum motion to contact the upper surface of the sheet to switch back in the direction of the stapler 41, and abuts the rear end of the sheet against the reference fences 39 and 40 to thereby detect the longitudinal position of the sheet bundle (in the conveying direction). Position). In the sheet bundle PB thus aligned, in the end binding mode, the stapler 41 moves along the rear end of the sheet bundle PB and binds the appropriate position at the lower edge of the sheet bundle PB. The bound sheet bundle PB is sandwiched between the paper discharge driven roller 31 and the paper discharge driving roller 33 and is discharged onto the paper discharge tray 32 by applying a conveying force.

  In the saddle stitching mode, after the alignment and stapling of the sheet P or the sheet bundle PB are completed, the sheet bundle PB is sandwiched by the clamp movable fences 120 and 121, and the reference fences 39 and 40 serve as an obstacle to the conveyance of the sheet bundle PB. Evacuate outside the sheet width so that it does not become. The clamp movable fences 120 and 121 are attached to a clamp vertical axis 106 arranged outside the apparatus side plate, and are arranged in the vertical direction (vertical direction) and in the horizontal direction (horizontal direction: FIG. 1) along the curved fourth transport path 4. Move left and right).

  The clamp movable fences 120 and 121 are moved by the clamp longitudinal axis 106 in the vertical direction and moved along the guide rail 110 on the apparatus side plate which is the same locus as the curved locus of the fourth transport path 4 in the lateral direction. Then, the sheet bundle PB is conveyed along the conveyance path 4. The sheet bundle PB with the rear end of the sheet sandwiched is conveyed along a track of the guide rail 110 to a predetermined position corresponding to the sheet size, and is saddle stitched at an appropriate position of the sheet bundle length center portion. The predetermined position corresponding to the sheet size is a position sent from the clamp movable fence home position sensor 49 by a predetermined pulse.

The saddle-stitched sheet bundle PB is further conveyed downward by the clamp movable fences 120 and 121, stops when the central portion of the sheet size length is at the position of the folding blade 203, and proceeds to the folding process. The stop position is a position where the folding position sensor 50 detects the trailing edge of the sheet and is sent a predetermined pulse corresponding to the sheet size. Next, the central portion of the sheet bundle length stopped at the folding position is introduced into the press folding unit 200 by the folding blade 203 and the conveying rollers 206 and 207.

  As will be described in detail later, in the press folding unit 200, the center portion of the introduced sheet bundle length is pressed from above and below by the upper and lower press plates 219 and 220, and the center is folded by moving the press position. At this time, the abutting member 301 is abutted against the folding leading end W of the sheet bundle PB to be folded. The folded sheet bundle PB is discharged onto the saddle stitching tray 62 by the conveying rollers 206 and 207 and the discharge roller 58. Note that the abutting member 301 has a dimension in the sheet width direction in which the folded leading end W of the sheet bundle PB can abut with the full width in the sheet width direction orthogonal to the sheet conveyance direction. In other words, it has a depth dimension (dimension in the longitudinal direction) that is equal to or larger than the maximum width direction size of the sheet.

  The sheet bundle PB discharged to the saddle stitching tray 62 is pressed by a sheet pressing roller 61 attached to the sheet presser 60 so that the folded sheet bundle PB swells and does not interfere with the discharge of the sheet bundle to be discharged next. It has become.

  The sheet folding unit 119 having the sheet punching unit 101 and the conveyance path 4 is detachable, and a sheet post-processing apparatus according to the needs of the user can be provided.

  FIG. 2 is a perspective view of the press fold portion, and FIG. 3 is a front view of the press fold portion as viewed from the front side of the apparatus. The press folding unit 200 is provided in the center folding unit 119, and includes a press plate driving cam 201, a folding blade driving cam 202, a folding blade 203, a folding blade support bar 204, and both side plates 205 on the front and rear sides of the apparatus. When the folding blade drive cam 202 is rotated, the folding blade support rod 204 is fitted with play (hereinafter referred to as “free fitting”). The folding of the cam blade 202a and the horizontal groove 205a of the side plate 205 causes the folding. The blade support bar 204 moves horizontally along the horizontal groove 202c (see FIG. 5), and the folding blade 203 moves in the arrow Q direction (see FIG. 9). Thereby, the center part of the sheet length of the sheet bundle PB is guided to the press folding part 200.

  4 is a view showing a state in which the press plate drive cam 201, the folding blade drive cam 202, and the side plate 205 are removed from FIG. 2, and FIG. 5 is a front view of FIG. 4 viewed from the front side of the apparatus.

  In these drawings, the press part folding part 200 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 bundle PB guided to the press folding unit 200 by the folding blade 203 conveys the folding leading end P part W of the sheet bundle PB to the press folding unit 200 by the conveying rollers 206 and 207. As the moving plate 208 moves, the press guide rollers 211 and 212 and the press pressure releasing cams 209 and 210 connected to the moving plate 208 move in the sheet conveying direction (arrow Q direction), and the moving plate 208 reciprocates. Accordingly, the press guide rollers 211 and 212 and the press pressure releasing cams 209 and 210 also reciprocate. The moving plate 208 is driven in the horizontal direction by a pin 208 a loosely fitted on the press plate driving cam 201.

  That is, the pin 208 a provided on the moving plate 208 shown in FIG. 4 is loosely fitted in the spiral cam groove 201 a of the press plate driving cam 201 on the inner side in the drawing of the moving plate 208, and the cam according to the rotation of the press plate driving cam 201 It functions as a cam follower for the groove 201a and moves in the horizontal direction. As a result, the moving plate 208 reciprocates in the direction of the arrow Q and the direction of the counter arrow Q along the same locus as the pin 208a.

  In addition, press pressure release cams 209 and 210 are fixed to the moving plate 208, and move together as the moving plate 208 moves. On the other hand, as shown in FIG. 5, the shaft ends of the press guide rollers 211 and 212 are also loosely fitted in the grooves 208b and 208c of the moving plate 208, and the press guide rollers 211 and 212 are moved in accordance with the movement of the moving plate 208 in the arrow Q direction. Moves on the press plates 219 and 220 in the same direction, and the nips of the press plates 219 and 220 are moved as described later with reference to FIG. 10 to fold the sheet bundle PB.

  The press plate drive cam 201 and the folding blade drive cam 202 are driven by a folding drive motor (not shown), a folding drive motor timing belt, a folding drive pulley, a folding drive unit timing belt, a folding blade drive gear, and a press plate drive gear. Etc. In the drive mechanism constituted by the above elements, when the folding drive motor rotates, the driving force of the rotation shaft of the folding drive motor is transmitted to the folding drive motor timing belt via the pulley, and further, the folding drive pulley transmits the folding drive unit. The folding blade drive gear rotates and drives the folding blade drive cam, and the press plate drive gear rotates and drives the press plate drive cam. Since the folding blade driving gear and the press plate driving gear are engaged with and driven by the same folding driving unit timing belt, they are reliably driven synchronously.

  Further, the shaft 204 integral with the folding blade 203 shown in FIG. 5 moves through the spiral cam groove 202 a of the folding blade driving cam 202, and the folding blade 203 is provided in the horizontal groove 202 c provided on the stay 202 b of the folding blade driving cam 202. It can be moved along the horizontal direction. That is, both ends of the shaft 204 are loosely fitted in the spiral cam groove 202a of the folding blade drive cam 202, and the folding blade 203 is allowed to move only along the horizontal groove 202c with respect to the sheet. The rotary motion of the folding blade drive cam 202 is converted into the linear reciprocating motion of the folding blade 203.

  6 is a perspective view showing a state in which the moving plate 208 is removed from FIG. 4, and FIG. 7 is a front view seen from the front side of the apparatus in which the dotted line portion H in FIG. 6 is enlarged.

  6 and 7, the upper press unit 217 and the lower press unit 218 located above and below the sheet conveyance path are in a state in which pressure is applied by springs at the four corners of the unit corner. In the standby state, the press upper unit 217 and the press lower unit 218 are separated from each other by the press pressure releasing cams 209 and 210 provided inside the moving plate 208, and this state is the state of the folding leading end portion of the sheet bundle PB. Accepted state.

  When the moving plate 208 moves in the direction of arrow Q, the press pressure releasing cams 209 and 210 attached to the moving plate 208 move, and the pressure releasing rollers 213 and 215 of the upper press unit 217 and the pressure releasing roller of the lower press unit 218 are moved. 214 and 216 move in the directions of arrows A and B by the inclined surfaces of the press pressure release cams 209 and 210, thereby pressing the folded portion front end P1 of the sheet bundle PB.

  8 is a view showing the inside of the press unit of FIG. 3, and FIG. 9 is a front view of FIG. 8 as seen from the front side of the apparatus.

  8 and 9, an upper press plate 219 and a lower press plate 220 are respectively provided in the press upper unit 217 and the press lower unit 218 inside the press unit, and the upper and lower press plates are moved by the movement of the press pressure release cams 209 and 210. In conjunction with the units 217 and 218, the upper press plate 219 moves in the direction of arrow A and the lower press plate 220 moves in the direction of arrow B. By this movement, the sheet bundle PB is sandwiched between the upper and lower press plates 219 and 220 and folded.

  The press guide rollers 211 and 212 connected to the moving plate 208 move on the upper and lower press plates 219 and 220 in conjunction with the movement of the moving plate 208 in the arrow Q direction. By this movement, the sheet bundle is moved by the curved shape of the upper and lower press plates 219 and 220 that can move and rotate along the grooves 221, 222, 223, and 224 (see FIG. 7) on the side surfaces of the upper and lower press units 217 and 218. Folding is performed toward the fold end P1 of the PB. At this time, the folding tip is pressurized by the abutting member 301.

  Hereinafter, each embodiment of the press folding unit 200 will be described. The press folding unit 200 in the following examples is based on the sheet post-processing apparatus 100 in the embodiments described so far, and in this embodiment, the press folding unit 200 functions as a sheet folding device. In addition, in each embodiment, the same reference numerals are given to the respective components having the same configuration or the same function, and the overlapping description is appropriately omitted.

  10 and 11 are diagrams showing details and operation of the press folding unit provided with the abutting member in Example 1, FIG. 10 is a front view showing the state at the start of press folding, and FIG. 11 is the state of FIG. FIG. 9 is a front view showing a state after the upper press plate 219 and the lower press plate 220 press the sheet bundle PB by squeezing it toward the folding tip end according to the curved shape.

  As shown in FIG. 10, the press folding unit 200 is provided immediately downstream of the nip of the transport rollers 206 and 207, and detects the sheet bundle PB, the upper and lower press plates 219 and 220, and the upper An abutting member 301 is provided on the most downstream side in the sheet conveying direction of the press plate 219. The distance between the sheet detection sensor 310 and the abutting member 301 is T. Further, in order to abut the folding front end portion W of the sheet bundle PB against the abutting member 301, the sheet detection sensor 310 detects the folded front end portion W, and after being turned ON, the sheet bundle PB is conveyed by a distance T, and The distance that is transported beyond the distance T is defined as an abutting amount α.

  When the press folding unit 200 is configured in this way, the sheet bundle PB is conveyed by the conveyance rollers 206 and 207, and when the folding leading end W of the sheet bundle PB reaches the position of the sheet detection sensor 310, the sheet detection sensor 310 is folded. The part W is detected, and the sheet detection sensor 310 is turned on. When the sheet detection sensor 310 is turned on, the conveyance rollers 206 and 207 convey the sheet bundle PB by a distance (T + α), and then stop.

  Next, as shown in FIG. 10, first, the center portion X of the sheet bundle PB is sandwiched between the upper plate 219 and the lower plate 220. This sandwiched position is a clamping point for clamping the sheet bundle PB in a pressurized state. The upper press plate 219 and the lower press plate 220 are gradually sandwiched from the upstream side in the conveyance direction of the sheet bundle PB toward the folding front end W on the downstream side in the conveyance direction (clamping point) along the curved shape of both. The sheet bundle PB is squeezed and pressurized while changing. At this time, since the folding leading end W loses its escape, it gradually shifts to the downstream side in the conveying direction, and finally protrudes from the end surface E on the downstream side in the sheet conveying direction of the upper and lower press plates 219 and 220, It strikes against the abutting member 301.

  As shown in FIG. 11, when the position where the sheet bundle PB is sandwiched (clamping point) reaches the upstream portion Y in the conveying direction of the folding tip W, the upper press plate 219 and the lower press plate 220 stop. At this time, since the sheet is conveyed by the amount of the abutting amount α, when the folded leading end W of the sheet bundle PB abuts against the abutting member 301, the escape place is lost. And, it enters the gap Z provided between the abutting surface 301a of the abutting member 301 and the end surface E on the most downstream side in the sheet conveying direction of the upper press plate 219 and the lower press plate 220, and in this state the sheet conveying direction The folding tip W is folded. Thereafter, the upper press plate 219 and the lower press plate 220 are separated from each other.

  In the first embodiment, the abutting member 301 is fixed to the front side plate (front side plate) and the back side plate (rear side plate) of the sheet post-processing apparatus 100, and the folded sheet bundle PB is arranged. When paper is discharged, the transport rollers 206 and 207 are reversed to return to the upstream in the transport direction. However, without fixing the abutting member 301, for example, a rack and pinion mechanism can be provided, and the abutting member 301 can be moved in the direction perpendicular to the sheet conveying direction and retracted from the conveying path. . With this configuration, the folded sheet bundle PB can be discharged as it is downstream in the transport direction.

  FIG. 12 is a diagram showing a folded state of the sheet bundle PB when the folding tip W is not molded by the abutting member 301 (when it is molded by the conventional folding method), and FIG. It is a figure which shows a folding state at the time of shape | molding. When the folding tip portion W is not formed, the folding portion tip Wa is folded at an acute angle at one place as shown in FIG. However, in this folded shape, folding may return due to the elastic force of the sheet bundle PB, and the opposite side of the folded portion may open, resulting in an increase in the folding height R1.

  On the other hand, the sheet bundle PB in which the folding leading end portion W is pressed by the abutting member 301 as in the first embodiment is substantially the same as viewed from the direction (width direction) perpendicular to the sheet conveying direction. It is formed into a letter shape (channel shape). That is, as can be seen from FIG. 13, the folding tip W is pressed to form a flat surface Wh, so that it is sandwiched between the end surfaces K of the upper and lower press plates 219, 220, and on the upper side and the lower side, respectively. First and second folds Wb1, Wb2, Wc1, Wc2 are formed. As a result, the second creases Wb2 and Wc2 become obtuse and the elastic force of the sheet bundle PB does not act greatly. Therefore, the opposite side of the folded portion of the sheet bundle PB is not opened, and a flat state is maintained as shown in FIG. As a result, the folding height R2 is not increased, and a low state can be maintained.

  The pressurization control of the folding tip W is performed, for example, with a control configuration shown in FIG. FIG. 14 is a block diagram showing a control configuration of the sheet post-processing apparatus 100 related to the present embodiment. The control unit of the sheet post-processing apparatus 100 includes a CPU 100-1, a memory 100-2, a motor control unit 100-3, and a sheet detection sensor 310. The CPU 100-1 includes a ROM and a RAM (not shown), expands a program stored in the ROM to the RAM, and executes control defined by the program while using the RAM as a work area and a data buffer. The memory 100-2 can be used as the RAM.

  The motor control unit 100-3 controls the driving of a folding motor (not shown) and a conveying motor that drives the conveying roller 206 according to an instruction from the CPU 100-1. Here, the drive control means ON / OFF control, forward / reverse rotation control, and speed control. The CPU 100-1 receives sheet information such as the number of sheets, thickness, and size transmitted from the image forming apparatus PR main body by the communication unit 100-1a, and the rotation speed of the folding drive motor based on the received sheet information. Is controlled to change the moving speed of the pressing positions of the upper and lower press plates 219 and 220, thereby shortening the useless folding time. That is, when the number of sheets is large, when the sheet thickness is thick, or when the sheet size is large, it is necessary to increase the integrated value of the pressure for folding the sheet bundle PB with respect to the sheet bundle PB. Good. Therefore, the moving speed of the pressing position is controlled as described above based on information such as the number of sheets, thickness, and size.

  The motor control unit 100-3 controls driving of the driving-side transport roller 206 driven by the transport motor to control the transport amount of the sheet bundle PB. That is, the sheet is conveyed by a conveyance amount (T + α) corresponding to the distance T and the protrusion amount α using the detection timing of the sheet detection sensor 310 as a trigger. Then, after the sheet bundle PB is stopped, the pressing operation by the upper and lower folding plates 219 and 220 is started as described above.

  Note that an operation panel PR1 as a user interface is connected to the main body of the image forming apparatus PR, and a user can input an instruction during image formation and an instruction for post-processing. In addition, on the operation panel PR1, a selection screen for inputting an instruction, a work state, a progress, and the like are displayed.

  FIG. 15 is a flowchart illustrating the sheet folding operation procedure according to the first exemplary embodiment. This operation is executed by the CPU 100-1 of the sheet post-processing apparatus 100.

  In this procedure, the sheet bundle PB is awaited, and the sheet detection sensor 310 detects the leading end of the sheet bundle PB. When the sheet detection sensor 310 is turned on (step S101: YES), the sheet bundle PB is detected by the conveyance rollers 206 and 207. The distance (T + α) is conveyed from the timing when 301 is turned on (step S102).

  Next, the upper press plate 219 and the lower breath plate 220 pressurize the sheet bundle PB, and the front end portion of the sheet bundle PB is folded by the above-described operation (step S103). When the desired folding is applied to the folding leading end W, the upper and lower press plates 219 and 220 are separated from each other, and the pressure state on the sheet bundle PB is released (step S104). In this operation procedure, in step S3, the folding leading end W abuts against the abutting member 301, and folding is performed so that the leading end as shown in FIG. 11 is formed as a flat surface Wh.

  As described above, in this embodiment, when the sheet bundle PB is folded by the upper and lower press plates 219 and 220 as the press folding means, the sheet bundle PB is narrowed down as shown in FIGS. The folding tip W is folded while abutting against the abutting member 301. Thereby, the fold can be formed in a U-shaped cross section. When the folds are formed so as to have a U-shaped cross section, strong folding can be realized, the folding is weak and the sheet is prevented from bulging, and the folding height can be reduced. At this time, since the folded portion is formed by a single folding process, a reduction in productivity can be minimized.

  FIG. 16 is a diagram illustrating the details and operation of the press folding portion including the abutting member in the second embodiment, and is a front view illustrating a state at the time of pressing illustrated in FIG. 11 in the first embodiment.

  In the second embodiment, the abutting surface 301a of the abutting member 301 and the end surface E on the downstream side in the conveying direction of the upper and lower press plates 219 and 220 are the former curved surface and the latter a concave curved surface. is there. Both of them are set to have such a curvature that they come into contact with the same curved surface when the abutting surface 301a is pressed against the end surface E. Other parts are the same as those in the first embodiment. When the pressing surface is configured by the abutting surface 301a and the concave end surface E in this way, when the sheet bundle PB is pressed, the folded tip portion W of the sheet bundle PB follows the curved pressing surface formed by both of them. To be molded.

  In the second embodiment, the abutting member 301 is fixed to the front side plate and the rear side plate in the same manner as in the first embodiment. For example, a rack and pinion mechanism is provided, and the abutting member 301 is arranged in the sheet conveyance direction. The sheet bundle PB which is retracted in the vertical direction and is folded can be configured to be discharged downstream in the transport direction.

  Other parts not specifically described are configured in the same manner as in the first embodiment and function in the same manner.

  As described above, according to this embodiment, when the upper press plate 219 and the lower press plate 220 sandwich the position of the upstream portion Y in the conveyance direction of the folding tip W and pressurize the sheet bundle PB, the upper press plate The arcuate end surface E of the sheet press 219 and the lower press plate 220 strongly presses the folding leading end W of the sheet bundle PB against the arcuate abutting member 301, and the gap Z is narrowed, thereby forming a strong crease. be able to. As a result, the effects of the first embodiment are exhibited and the effect of reducing the folding height is further increased.

  FIG. 17 is a diagram illustrating details and operation of the press folding unit including the abutting member according to the third embodiment. This figure shows a state in which the folding tip portion W of the sheet bundle PB is not abutted against the abutting member 301 and the shape shown in FIG. 12 is folded only by the upper press plate 219 and the lower press plate 220.

  When the number of sheet bundles PB is small, the folding height in the folding shown in FIG. 13 is not less than a certain value in a U-shape, so that the folding height is higher than in the folding shown in FIG. There is a case. Therefore, in this embodiment, it is selected whether to fold only with the upper press plate 219 and the lower press plate 220 shown in FIG. 17 or to fold with the upper press plate 219 and the lower press plate 220 and the abutting member 301 shown in FIG. To do. This selection is arbitrarily selected from the selection screen on the operation panel PR1 of the image forming apparatus PR when the user instructs the main body of the image forming apparatus PR to fold. For example, when the number of sheets to be folded shown in FIG. 17 is selected from the selection screen of the operation panel PR1, if the number of folding shown in FIG. Folding suitable for the number of sheet bundles PB can be performed.

  In the folding according to the third embodiment, when the conveyance amount by the conveyance rollers 206 and 207 is the first embodiment, the conveyance amount is a position at a distance T from the position of the sheet detection sensor 310 and is not in contact with the abutting member 301. Set to distance U. That is, when the leading end of the sheet bundle PB reaches the position of the sheet detection sensor 310, the sheet detection sensor 310 detects the leading end, and the sheet detection sensor 310 is turned on. When the sheet detection sensor 310 is turned on, the conveyance rollers 206 and 207 convey the sheet bundle PB by the distance U and stop. At this time, the folded leading end W of the sheet bundle PB is at a predetermined position that does not reach the abutting member 301. Thereafter, the upper press plate 219 and the lower press plate 220 are folded.

  When folded in this way, the number of sheets is small, so that the sheet bundle PB does not swell due to the elasticity or waist of the sheet as shown in FIG. 12, and is formed on the flat front surface Wh at the folding tip W of the sheet bundle PB. Therefore, it can be made lower than the formation height (booklet thickness) of the flat surface Wh.

  FIG. 18 is a flowchart illustrating the sheet folding operation procedure according to the third embodiment.

  In this procedure, waiting for the sheet P to be carried in, when the sheet detection sensor 310 detects the leading end of the sheet P and is turned on (step S201: YES), the butt fold (fold shown in FIG. 11 or FIG. 13) is selected. Whether or not the butt fold is selected, and the sheet bundle PB is conveyed by the conveying rollers 206 and 207 by the distance (T + α) from the timing when the sheet detection sensor 301 is turned on. Transport (step S203).

  Next, the upper press plate 219 and the lower breath plate 220 pressurize the sheet bundle PB, and the front end portion of the sheet bundle PB is folded by the above-described operation (step S205). When the desired folding is applied to the folding leading end W, the upper and lower press plates 219 and 220 are separated from each other, and the pressure state on the sheet bundle PB is released (step S206).

  On the other hand, if the butt fold is not selected in step S202a, the fold shown in FIG. 17 or 12 is selected, and the timing at which the sheet detection sensor 301 is turned on for the sheet bundle PB by the conveying rollers 206 and 207. From the distance U (step S204), and the processes of steps S205 and S206 are executed.

  In this operation procedure, according to the selection result of the folding type in step S202a, the leading end as shown in FIG. 13 is folded so that the flat surface Wh is formed in the direction orthogonal to the conveying direction, or the leading end shown in FIG. The upper and lower press plates 206 and 207 are pressed to fold the folding tip W so as to have an acute angle.

  The third embodiment is a folding variation of the first embodiment, and each part that is not particularly described is configured in the same manner as the first embodiment and functions in the same manner.

  As described above, according to the present embodiment, it is possible to select whether to fold the abutting member 301 by abutting the folding front end portion W of the sheet bundle PB or not folding. This makes it possible to perform folding processing suitable for the number and thickness of the sheet bundle PB. As a result, it is possible to reduce the folding height while minimizing the decrease in productivity.

  In the fourth embodiment, the folding type is changed by the selection operation of the operation panel PR1 in the third embodiment, and is changed based on the number of sheet bundles PB. That is, if the number of sheets whose folding type is to be changed is set in advance and the number of sheet bundles PB is greater than the preset number compared with the preset number, the folding leading end shown in FIG. 11 (FIG. 13). The portion W is folded so as to be a flat surface Wh, and when the number is less than the number, the folding tip portion W shown in FIG. 17 (FIG. 12) is folded at an acute angle. In the fourth embodiment, the sheet post-processing apparatus 100 or the image forming apparatus PR includes a counter (not shown) that counts the number of sheets, and the folding method is automatically switched based on information on the number of sheet bundles PB counted by the counter. .

  In this case, for example, if the set number of sheets is 10, if the number is 10 or more, it is determined that the folding height is high, and the folding shown in FIG. 13 is performed. If the number is less than 10, the folding shown in FIG. 12 is performed. .

  Note that the number of threshold values can be set to an arbitrary number by the user from the operation panel PR1 of the image forming apparatus PR. Further, it is also possible to acquire one sheet number information transmitted from the image forming apparatus PR and select a folding type based on the acquired sheet number information.

  FIG. 19 is a flowchart illustrating a sheet folding operation procedure according to the fourth embodiment.

  The flowchart shown in FIG. 19 is obtained by replacing the determination process of step S202a of FIG. 18 with the determination process of step S202b with respect to the flowchart of the third embodiment shown in FIG. In the determination process in step S202b in the fourth embodiment, it is determined whether or not the number of sheets is 10 or more. If the number is 10 or more, the processes in and after step S203 are executed to form the folding leading end portion W of the sheet bundle PB. The folding process for forming the flat surface Wh is executed. If the number of sheets is less than 10, the processes in and after step S204 are executed, and the folding process for forming the folding tip portion W at an acute angle is executed.

  Other parts not specifically described are configured in the same manner as in the first and third embodiments and function in the same manner.

  As described above, according to the present embodiment, the number of sheets is automatically determined and the folding type is automatically changed. Therefore, the same effect as in the third embodiment can be obtained by the determination on the machine side, and the user can The folding method can be switched without taking time and effort.

  In the fourth embodiment, the folding type is changed by comparing the number of sheets with a threshold value, whereas in the fifth embodiment, the folding type is changed based on the sheet thickness instead of the number of sheets. .

  In this embodiment, the sheet post-processing apparatus or the image forming apparatus includes a measurement unit that measures the thickness of the sheet (not shown), or includes a setting unit that allows the user to set the thickness of the sheet in advance. The folding method is automatically switched based on information on whether or not (information on whether or not the thickness of one sheet is greater than a preset thickness).

  In this embodiment, when the sheet thickness of one sheet is thicker than a preset thickness, it is determined that the folding height increases because the stiffness is strong, and the folding shown in FIG. 13 is performed regardless of the number of sheet bundles PB. Apply.

  FIG. 20 is a flowchart illustrating the operation procedure of sheet folding in the fifth embodiment.

  The flowchart shown in FIG. 20 is obtained by replacing the determination process of step S202a of FIG. 18 with the determination process of step S202c with respect to the flowchart of the third embodiment shown in FIG. In the determination process of step S202c in the fifth embodiment, based on the result of measurement by the measurement unit whether the sheet thickness is greater than or equal to a preset thickness, the user can use the operation panel PR1 to perform cardboard. Is set based on the setting result, and if it is thick paper, the process after step S203 is executed to perform a folding process for forming the flat surface Wh on the folding leading edge W of the sheet bundle PB. If it is not thick paper, the processing after step S204 is executed, and the folding processing for forming the folding tip W at an acute angle is executed.

  Other parts not specifically described are configured in the same manner as in the first and third embodiments and function in the same manner.

  As described above, according to the present embodiment, the folding process suitable for folding the thick paper is automatically selected and folded depending on whether the sheet is thick paper. Thus, the folding method can be switched without requiring the user to take time and effort.

  FIG. 21 is a diagram illustrating details and operation of the press folding unit including the abutting member according to the sixth embodiment. In this embodiment, the abutting member 301 is configured to be movable in the sheet conveying direction.

In this embodiment, as shown in FIG. 21, the abutting member 301 can be moved in the sheet conveying direction (arrow D1, D2 direction) by a driving source and a driving mechanism (not shown). the distance a _n between the sheet conveying direction downstream side of the end face E and the abutment member 301 of the pressing plate 220 can be arbitrarily set. The movement control is executed by the CPU 100-1 of the sheet post-processing apparatus 100.

If a small number spite distance a _n of the sheet bundle PB is wide, folding the leading end portion W of the sheet bundle PB is not abutted sufficiently abutment member 301, there is a risk that the folding is weakened. Further, when the number is large even though the interval a _n of the sheet bundle PB is narrow, folded tip W is not entering the spacing a _n, there is a possibility that creases are not formed in a U-shape. In contrast, when configured to be movable abutment member 301 can be set to the appropriate spacing a _n. As a result, the folding height can be reduced regardless of the number of sheet bundles P.

  Also in this embodiment, for example, a rack and pinion mechanism is provided, the abutting member 301 is retracted in a direction perpendicular to the sheet conveying direction, and the folded sheet bundle PB is discharged downstream in the conveying direction. It can also be configured to paper.

FIG. 22 is a flowchart illustrating the operation procedure of sheet folding in the sixth embodiment.
In this embodiment, the sheet number information of the sheet bundle PB is transmitted from the image forming apparatus PR, automatically switches the width of the spacing a _n. For example, when the number is 1 to 5 sheets to the distance _{a n} and _{a 1.} Similarly, it is a ₂ when it is 6 to 10 sheets, a ₃ when it is 11 to 15 sheets, and a ₄ when it is 16 sheets or more. The magnitude relationship between a _{1 to} a ₄ is
a ₁ > a ₂ > a ₃ > a ₄
It is.

The distance _{a n} is the interval of each _T 1 through T ₄ of the abutting surface 301a of the sheet detecting sensor 310 and the abutment member 301 when the _a 1 ~a _4. When increasing the number of the sheet bundle PB, to move the abutment member 301 in accordance with the increase in number, increase the distance a _n.

  Specifically, after waiting for the sheet P to be carried in, the sheet detection sensor 310 detects the leading end of the sheet P, and when it is turned on (step S301: YES), it is determined how many sheets are folded. The number of folded sheets can be confirmed from the sheet number information transmitted from the image forming apparatus PR side. Therefore, when the sheet detection sensor 310 is turned on in step S301, the number of folded sheets is 1 to 5 (step S302), 6 to 10 (step S303), 11 to 15 (step S304), or more. (Step S304: NO).

If 1-5 Like in step S302, moves the abutment member, and the distance _{a n} to _{a 1} (step S305), the amount abutted against the distance _{T 1} of the from the sheet detection sensor 310 of the interval is _{a 1} The sheet bundle PB is conveyed by the distance (T ₁ + α) obtained by adding α (step S309).

If 6-10 Like in step S303, similarly to the distance _{a n} in _{a 2} (step S306), the distance _{(T 2} + α) only to convey the sheet bundle PB (step S310).

If 11-15 Like in step S304, similarly to the distance _{a n} to _{a 3} (step S307), the distance _{(T 3} + α) only to convey the sheet bundle PB (step S311).

If 16 or more sheets in step S304 (step S304: NO), similarly to the distance _{a n} in _{a 4} (step S308), the distance _{(T 4} + α) only to convey the sheet bundle PB (step S312).

  When the conveyance of the sheet bundle PB is finished in each of steps S309, S310, S311, and S312, the upper press plate 219 and the lower breath plate 220 pressurize the sheet bundle PB, and the sheet bundle PB is folded to the leading end portion of the sheet bundle PB by the above-described operation. (Step S113). When the desired folding is performed on the folding leading end W, the upper and lower press plates 219 and 220 are separated from each other, and the pressure state on the sheet bundle PB is released (step S114).

  Other parts not specifically described are configured in the same manner as in the first embodiment and function in the same manner.

According to this embodiment, as described above, the abutment member 301 is movable in the sheet conveying direction, spacing a _n between the sheet conveying direction downstream side of the end face E and the abutment member 301 of the upper and lower pressing plates 219 and 220 Therefore, the abutting member 301 can be moved on the machine side to a position suitable for the number of sheet bundles PB and folded. As a result, regardless of the number of sheet bundles, it is possible to automatically perform a process of reducing the folding height while minimizing the decrease in productivity.

  In this embodiment, the sheet in the claims is denoted by symbol P, the sheet bundle is denoted by symbol PB, the sheet folding apparatus is denoted by the press folding unit 200, the conveying means is conveyed by the conveying rollers 206 and 207, and the folding means is denoted by the upper press plate. 219 and the lower press plate 220, the leading end of the sheet bundle is the folding leading end W, the abutting member is denoted by reference numeral 301, the abutting surface is denoted by reference numeral 301a, the crease forming means is the abutting member 301 and the upper and lower press plates 219. 220, the surface facing the abutting surface is the end face E on the downstream side in the transport direction of the upper and lower press plates 219, 220, the selection means is the CPU 100-1, and the acquisition means is the communication unit 100-1a and the CPU 100-1. The counting means is a counter (not shown), the interval adjusting means is a CPU 100-1, a driving source and a driving mechanism (not shown), and the image forming system is an image forming apparatus PR. The sheet post-processing apparatus 100 including the press-folding unit 200, the corresponding.

  Furthermore, the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the present invention, and all the technical matters included in the technical idea described in the claims are all included. The subject of the present invention. The above-described embodiments show preferred examples, but those skilled in the art can realize various alternatives, modifications, variations, and improvements from the contents disclosed in the present specification. These are included in the technical scope described in the appended claims.

100 sheet post-processing apparatus 100-1 CPU
100-1a Communication unit 200 Press folding unit (sheet folding device)
206, 207 Conveying roller 219 Upper press plate 220 Lower breath plate 301 Abutting member 301a Abutting surface E End surface of the upper and lower press plates on the downstream side in the conveying direction P Sheet PB Sheet bundle PR Image forming apparatus W Folding tip

JP 2010-64870 A

Claims (10)

A sheet folding apparatus for performing a folding process on a sheet or a sheet bundle,
Conveying means for conveying the folded sheet or the sheet bundle;
Folding means for holding the sheet or the sheet bundle conveyed by the conveying means from both sides and pressing while moving the clamping point from the upstream side to the downstream side in the sheet conveying direction;
A crease forming means for abutting the leading end of the sheet or the sheet bundle protruding from the folding means in the process of applying pressure to the abutting surface of the abutting member to crease the leading end;
A sheet folding apparatus comprising: The sheet folding apparatus according to claim 1,
The abutting surface is a flat or convex curved surface;
The sheet folding apparatus, wherein a surface of the folding unit that faces the abutting surface is a flat surface or a concave curved surface having a shape corresponding to the abutting surface. The sheet folding apparatus according to claim 1 or 2,
A sheet folding apparatus, comprising: a selection unit that selects whether to fold the sheet bundle against the abutting member or to fold the sheet bundle without abutting against the abutting member. . The sheet folding apparatus according to claim 3,
The sheet folding apparatus according to claim 1, wherein the selection unit selects based on the number of sheets or the thickness of the sheet bundle. The sheet folding apparatus according to claim 4,
Obtaining means for obtaining the number of sheets from a sheet conveying source;
The sheet folding apparatus according to claim 1, wherein the selection unit selects based on the number of sheets acquired by the acquisition unit. The sheet folding apparatus according to claim 4,
Having a counting means for counting the number of sheets;
The sheet folding apparatus according to claim 1, wherein the selection unit selects based on the number of sheets acquired by the counting unit. The sheet folding apparatus according to claim 4,
Obtaining means for obtaining the thickness of the sheet from a sheet conveying source;
The sheet folding apparatus according to claim 1, wherein the selection unit performs selection based on the thickness of the sheet acquired by the acquisition unit. The folding device according to any one of claims 1 to 7,
A sheet folding apparatus comprising: an interval adjusting unit that adjusts an interval between the abutting surface and a surface of the folding unit facing the abutting surface. An image forming system comprising the sheet folding device according to claim 1. A sheet folding method for performing a folding process on a sheet or a sheet bundle,
A first step of conveying the folded sheet or sheet bundle by a conveying means;
A second step in which the sheet or the sheet bundle conveyed in the first step is clamped from both sides by a folding means and pressed while moving the clamping point from the upstream side to the downstream side in the sheet conveying direction;
A third step of abutting the tip of the sheet or the sheet bundle protruding from the folding means in the second step against the abutting surface of the abutting member to crease the tip;
A sheet folding method comprising:

Images