JP2009208849A - Sheet folding device, sheet processing device, sheet conveying device and image forming device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To form a sheet bundle capable of enhancing a crease and having a thin and beautiful finish irrespective of the thickness of the sheet bundle. <P>SOLUTION: A sheet forming device comprises a folding plate, a folding roller which perform fold processing on a sheet or the sheet bundle after image formation, and a fold increasing roller 520 which moves along the crease of the sheet or sheet bundle folded by the folding roller and presses the crease again to enhance the crease. The sheet folding device comprises a guide member 528 receives the pressing force by the fold increasing roller 520 through the sheet or sheet bundle and a movement mechanism for moving the guide member 528 in a direction perpendicular to a sheet conveyance direction, wherein when the fold increasing roller 520 presses the crease again, the movement mechanism moves the guide member 528 in a direction separating from the fold increasing roller 520 and regulates a height of the fold increasing roller when it runs on the sheet bundle. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a sheet folding apparatus that performs a folding process on a sheet-like recording medium (hereinafter simply referred to as “sheet” or “sheet member”), a sheet processing apparatus including the sheet folding apparatus, a sheet conveying apparatus, and an image. The present invention relates to a forming apparatus.

  2. Description of the Related Art A sheet folding apparatus that performs a folding process on a sheet or a sheet bundle is widely used by being attached to a subsequent stage of an image forming apparatus as part of sheet processing after an image is formed, or integrally provided in an image forming apparatus. As such a sheet folding apparatus or an apparatus including the sheet folding apparatus, the inventions described in Patent Documents 1 to 4 are known.

  Of these, Japanese Patent Application Laid-Open No. H10-228867 describes that the fold-in roller does not hit the lower guide plate after the fold-in roller has been pressed while moving on the sheet bundle bending portion, so that a large noise is not generated. A folding roller that folds the paper while passing through the nip of the roller, and a folding roller that further folds the folded portion between the folded portion of the folded sheet bundle and the lower guide plate, In a paper processing apparatus that includes a guide member that moves a folding roller in a direction perpendicular to the paper conveyance direction and a pulse motor that moves the folding roller along the guide member, An invention is disclosed in which a buffer means, for example, an elastic material on the lower guide plate or a flange made of an elastic material on the side of the additional roller is provided at the contact portion between the guide plate and the additional roller. .

  Further, Patent Document 2 discloses that when a fold is added to a fold, it is reliably transmitted to the fold of the sheet bundle so that the fold of the sheet bundle can be sufficiently increased. In a paper processing apparatus having a folding roller for moving in a direction intersecting with the paper bundle conveying direction and re-pressurizing the folded portion of the paper bundle, the folding line of the paper bundle of the folding roller according to the number of paper bundles An invention provided with a control means for setting a pressurizing position for pressurizing the head is disclosed.

  Further, in Patent Document 3, when the folding means rides on the bent portion of the recording body, the recording body does not shift in the driving direction of the folding means, and the entire folding portion of the recording body is added by the folding means. In order to enhance the uniform re-pressing force and form a beautiful bent part, the recording medium to be fed is aligned and formed after the recording image is formed, and the conveyed recording medium is guided. Guiding means, and folding means for moving in a direction crossing the conveying direction of the recording medium that is conveyed and placed by the guiding means, and re-pressurizing the bending portion of the recording medium to increase the folding amount, An invention is disclosed that includes a supporting member that supports a side surface of the recording medium when the folding means is folded and added to the bent portion of the recording medium that is transported and placed on the guide means.

Also, Patent Document 4 describes a configuration that folds after a middle fold.
JP 2004-59304 A JP 2005-89140 A JP 2005-162345 A Japanese Patent No. 3746479

  In the inventions described in Patent Documents 1 to 4, in order to re-press and fold the folded portion of the folded sheet bundle, the sheet is pressed while the folded portion is pressed by a folding roller along the folded portion of the sheet bundle. It is moved in a direction orthogonal to the transport direction. Since the folding part is pressurized by the folding roller, the folding height of the sheet bundle can be reduced. However, even if the folding height of the sheet bundle can be reduced by the additional folding roller, the guide plate provided at the position facing the additional folding roller is fixed. The load to enter will increase. Therefore, in order to cope with this, if the guide plate is arranged in accordance with the thick sheet bundle, folding of the thin sheet bundle becomes sweet.

  Further, when the sheet bundle becomes thick, an excessive load is applied when the fold-up roller rides on the fold, and the motor may step out. In addition, the end face of the sheet bundle at the position where the sheet is particularly placed on the sheet bundle may be damaged.

  Accordingly, the problem to be solved by the present invention is to make it possible to create a beautifully finished sheet bundle that can be creased regardless of the thickness of the sheet bundle and has a small thickness.

  In order to solve the above-mentioned problem, the first means moves along a folding means for performing a folding process on the sheet or sheet bundle after image formation, and a fold of the sheet or sheet bundle folded by the folding means. A sheet folding device including a folding unit that repressurizes the fold and reinforces the fold, and a guide member that receives a pressure applied by the folding unit via a sheet or a sheet bundle, and conveys the guide member Moving means for moving in a direction orthogonal to the direction, and the moving means moves the guide member in a direction away from the folding means when the folding means repressurizes the fold. The ride height is adjusted when riding on the end portion of the sheet bundle.

  The second means is characterized in that in the first means, setting means is provided for setting the amount of movement of the guide member by the moving means based on at least one of the thickness, size, and number of sheets of the sheet. To do.

  The third means is characterized in that, in the first means, the fold-increasing means includes a rolling member that rolls on the fold in a direction perpendicular to the sheet conveying direction along the fold.

  The fourth means is characterized in that, in the first means, the moving means moves the guide member before starting the folding operation by the folding means.

  A fifth means is characterized in that, in the first means, the moving means moves the guide member to a position before the folding operation is started after the folding operation by the folding means is completed. To do.

  The sixth means is characterized in that the sheet processing apparatus includes the sheet folding apparatus according to any one of the first to fifth means.

  The seventh means is characterized in that the sheet conveying apparatus includes the sheet folding apparatus according to any one of the first to fifth means.

  The eighth means is characterized in that the image forming apparatus includes the sheet folding apparatus according to any one of the first to fifth means.

  The ninth means is characterized in that the image forming apparatus includes the sheet processing apparatus according to the sixth means.

  The tenth means is characterized in that the image forming apparatus includes the sheet conveying apparatus according to the seventh means.

  In the embodiments described later, the folding means is the first folding roller 81 and the folding plate 74, the folding means is the folding portion 525, the guide member is the guide plate 528, the setting means is the CPU 360, and the rolling member is folded. The sheet folding device and the sheet conveying device correspond to the saddle stitching / folding processing tray G, the sheet processing device corresponds to the sheet post-processing device PD, and the image forming device corresponds to the symbol PR.

  According to the present invention, the moving means moves the guide member in a direction away from the folding-increasing means when the folding-increasing means repressurizes the fold, and the folding-increasing means is performed regardless of the thickness of the sheet bundle. Since it is possible to set the amount of riding up to an appropriate amount and fold it up, it is possible to create a beautifully finished sheet bundle with no thickness without impairing the strengthening of the folds.

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

  FIG. 1 is a diagram showing a system configuration of a system including a sheet post-processing apparatus PD as a sheet processing apparatus and an image forming apparatus PR according to an embodiment of the present invention.

  In FIG. 1, the sheet post-processing apparatus PD is attached to the side portion of the image forming apparatus PR, and the sheet discharged from the image forming apparatus PR is guided to the sheet post-processing apparatus PD. The sheet has a conveyance path A having post-processing means for performing post-processing on one sheet (in this embodiment, a punch unit 100 as a punching means), and a conveyance path that leads to the upper tray 201 through the conveyance path A. B, the transfer path C leading to the shift tray 202, and the transfer path D leading to the processing tray F for performing alignment, stapling, and the like are configured to be distributed by the branch claw 15 and the branch claw 16, respectively.

  The image forming apparatus PR includes an image processing circuit that converts input image data into printable image data, although not shown, and an optical writing device that performs optical writing on a photoconductor based on an image signal output from the image processing circuit A developing device for developing the latent image formed on the photosensitive member by optical writing, a transfer device for transferring the toner image visualized by the developing device to the sheet, and a fixing device for fixing the toner image transferred on the sheet At least the sheet on which the toner image is fixed is sent to the sheet post-processing apparatus PD, and desired post-processing is performed by the sheet post-processing apparatus PD. Here, the image forming apparatus PR is of an electrophotographic system as described above, but any known image forming apparatus such as an ink jet system or a thermal transfer system can be used. In this embodiment, the image processing circuit, the optical writing device, the developing device, the transfer device, and the fixing device constitute image forming means.

  The sheet guided to the processing tray F (hereinafter referred to as a staple tray F) through the transport paths A and D, and aligned and stapled by the staple tray F is guided to the shift tray 202 by the guide member 44. A sheet which is configured to be distributed to a path C, a saddle stitching / folding processing tray G for performing folding or the like (hereinafter also simply referred to as a “saddle stitching processing tray”). It is guided to the lower tray 203 through the conveyance path H. Further, a branching claw 17 is disposed in the conveyance path D, and is held in the state shown in the figure by a low load spring (not shown). After the trailing edge of the sheet conveyed by the conveyance roller 7 passes through the branching claw 17. At least the conveying roller 9 among the conveying rollers 9 and 10 and the staple paper discharge roller (brush roller) 11 is reversely rotated to reverse the sheet along the turn guide 8. As a result, the sheet is guided from the rear end of the sheet to the sheet storage portion E to be retained (pre-stacked), and can be conveyed while being overlapped with the next sheet. By repeating this operation, two or more sheets can be stacked and conveyed.

  In the conveyance path A common to the upstream of the conveyance path B, the conveyance path C, and the conveyance path D, an inlet sensor 301 that detects a sheet received from the image forming apparatus PR, an inlet roller 1, a punch unit 100, The punch and waste hopper 101, the conveying roller 2, the branching claw 15 and the branching claw 16 are sequentially arranged. The branching claws 15 and 16 are held in the state shown in FIG. 1 by a spring (not shown). When the solenoid (not shown) is turned on, the branching claws 15 and 16 are driven to change the combination of the two. The sheet is distributed to the path B, the conveyance path C, and the conveyance path D.

  When the sheet is guided to the conveyance path B, the solenoid is turned off in the state of FIG. 1, and when the sheet is guided to the conveyance path C, the branch claw 15 is moved upward by turning on the solenoid from the state of FIG. Each of the branching claws 16 is rotated downward, and discharges the sheet from the conveying roller 3 to the upper tray 201 via the paper discharge roller 4. When the sheet is guided to the conveyance path D, the branching claw 16 is in the state shown in FIG. 1 and the solenoid is turned off, and the branching claw 15 is turned upward from the state shown in FIG. The sheet is conveyed to the shift tray 202 side through the paper roller pair 6 (6a, 6b).

  In this sheet post-processing apparatus, punching (punch unit 100), sheet alignment + edge binding (jogger fence 53, end surface binding stapler S1), sheet alignment + saddle binding (saddle stitch upper jogger fence 250a, Each processing such as the saddle stitching lower jogger fence 250b, the saddle stitching stapler S2), the sheet sorting (shift tray 202), and the middle folding (folding plate 74, folding roller 81) can be performed. Further, a folding process (folding unit 525-see FIG. 12) for further folding the folds of the sheet bundle folded in the latter stage of the folding process is possible.

  As shown in FIG. 1, the shift tray paper discharge unit located at the most downstream portion of the sheet post-processing apparatus PD includes the shift paper discharge roller pair 6 (6a, 6b), the return roller 13, and the paper surface detection sensor 330. And a shift tray 202, a shift mechanism that reciprocates the shift tray 202 in a direction orthogonal to the sheet conveyance direction, and a shift tray lifting mechanism that lifts and lowers the shift tray 202.

  In FIG. 1, the return roller 13 is a sponge roller for contacting the sheet discharged from the shift discharge roller pair 6 and aligning the rear end of the sheet against the end fence. The return roller 13 is rotated by the rotational force of the shift paper discharge roller pair 6. A tray lift limit switch is provided in the vicinity of the return roller 13, and when the shift tray 202 is lifted to push up the return roller 13, the tray lift limit switch is turned on and the tray lift motor is stopped. Thereby, overrun of the shift tray 202 is prevented.

  Further, as shown in FIG. 1, a paper surface detection sensor 330 is provided in the vicinity of the return roller 13 as paper surface position detecting means for detecting the paper surface position of the sheet or sheet bundle discharged on the shift tray 202. When the paper surface detection sensor 330 detects that the sheet stacking amount has reached a predetermined height, the shift tray 202 is lowered by a predetermined amount by driving the tray lifting motor. Thereby, the paper surface position of the shift tray 202 is kept substantially constant.

  The shift paper discharge roller 6 has a drive roller 6a and a driven roller 6b. The driven roller 6b is supported on the free end portion of the open / close guide plate that is supported on the upstream side in the sheet discharge direction and is rotatable in the vertical direction. Has been. The driven roller contacts the driving roller 6a by its own weight or urging force, and the sheet is nipped between the rollers and discharged. When the bound sheet bundle is discharged, the open / close guide plate is rotated upward and returned at a predetermined timing. This timing is determined based on the detection signal of the shift paper discharge sensor 303. Is done. The stop position is determined based on a detection signal of a paper discharge guide plate opening / closing sensor (not shown), and is driven by a paper discharge guide plate opening / closing motor (not shown).

  The sheets guided to the staple tray F by the staple paper discharge roller 11 are sequentially stacked on the staple tray F. In this case, each sheet is returned in the vertical direction (sheet conveyance direction) by the return roller 12 and is brought into contact with the rear end fence 51 and aligned, and the jogger fence 53 is aligned in the horizontal direction (direction perpendicular to the sheet conveyance direction-sheet width direction). (Also referred to as). The end-face stitching stapler S1 is driven by a staple signal from the control circuit 350, which will be described later, between the end of the job, that is, from the last sheet of the sheet bundle to the first sheet of the next sheet bundle, and the binding process is performed. Note that reference numeral 110 denotes a sheet presser that presses the sheet end surface when binding by the end surface binding stapler S1.

  The release claw 52 a is configured such that the home position is detected by a release belt HP sensor 311, and this release belt HP sensor 311 is turned on / off by a discharge claw 52 a provided on the discharge belt 52. Two discharge claws 52a are arranged at opposing positions on the outer periphery of the discharge belt 52, and the sheet bundle stored in the staple tray F is moved and conveyed alternately.

  The discharge belt 52 is positioned at the alignment center in the sheet width direction and is driven while being stretched between a driving pulley and a driven pulley. A plurality of discharge rollers 56 are arranged symmetrically with respect to the discharge belt 52, are provided so as to be rotatable with respect to the drive shaft, and function as driven rollers.

  The return roller 12 hits the fulcrum 12 a as a center and is given a pendulum motion by the SOL, and intermittently acts on the sheet fed to the staple tray F to abut the rear end of the sheet against the rear end fence 51. The return roller 12 rotates counterclockwise. A pair of jogger fences 53 are provided at the front and rear (ends in the width direction), and are driven by a jogger motor (not shown) capable of forward and reverse rotation via a timing belt to reciprocate in the sheet width direction. The end-face stitching stapler S1 is driven via a timing belt by a not-shown stapler moving motor (not shown), and moves in the sheet width direction to bind a predetermined position of the sheet edge.

  Here, the saddle stitching mechanism related to the folding process will be described. Since the present invention relates to the saddle stitching and folding mechanism, the end stitching mechanism is omitted.

FIG. 2 is a front view showing the end-face stitching processing tray F and the saddle stitching processing tray G, and FIGS. 3 to 10 are explanatory diagrams of operations in the saddle stitching binding mode.
In FIG. 1, the sheet sorted by the branching claw 15 and the branching claw 16 from the conveyance path A is guided to the conveyance path D, and is end-faced by the conveyance roller 7, the conveyance roller 9, the conveyance roller 10, and the staple discharge roller 11. The paper is discharged to the binding processing tray F. In the end-face binding processing tray F, the sheets sequentially discharged by the discharge rollers 11 are aligned in the same manner as in the stipple mode, and the operation is performed in the same manner as in the stipple mode until just before the stipple (see FIG. 3—sheet bundle). S indicates a state in which the rear end fence 51 is aligned).

  After the sheet bundle S is temporarily aligned in the end face binding processing tray F, as shown in FIG. 4, the leading edge of the sheet bundle is pushed up by the discharge claw 52a, and the roller 36 and the driven roller are released to a distance that does not interfere with the leading edge of the sheet bundle. 42 passes through to a position where the inner surface of the guide member 44 and the outer peripheral surface of the discharge roller 56 face each other. Next, the roller 36 is closed by the motor M1 which is a swing driving mechanism and the cam 40, the leading end of the sheet bundle is sandwiched between the roller 36 and the driven roller 42 with a predetermined pressure, and the roller 36 obtains a driving force from the timing belt 38. Further, the sheet is conveyed downstream along the path guided to the saddle stitching processing tray G as shown in FIG. The discharge roller 56 is provided on the drive shaft of the discharge belt 52 and is driven in synchronization with the discharge belt 52.

  The sheet bundle S is conveyed from the position shown in FIG. 5 to the position shown in FIG. 6. After entering the saddle stitching processing tray G, the sheet bundle S is conveyed by the upper bundle conveying roller 71 and the lower bundle conveying roller 72. At that time, the movable rear end fence 73 stands by at different stop positions according to the size of each sheet bundle S in the conveyance direction. When the leading edge of the sheet bundle comes into contact with the waiting movable rear end fence 73 and is stacked, the pressure under the bundle conveying roller 72 is released as shown in FIG. Tap the edge to make the final alignment in the transport direction. This is because there is a possibility that the sheet bundle S temporarily aligned in the end face binding processing tray F is stacked on the movable rear end fence 73, so that the final alignment is performed after the final alignment. This is because it is necessary to carry out with the end tapping claw 251.

  The position shown in FIG. 8 is the saddle stitching position, the movable rear end fence 73 stands by at the saddle stitching position, and final alignment in the width direction is performed by the saddle stitching upper jogger fence 250a and the saddle stitching lower jogger fence 250b. The center is bound by the saddle stitching stapler S2. Here, the movable rear end fence 73 is positioned by pulse control from the movable rear end fence HP sensor 322, and the rear end hitting claw 251 is positioned by pulse control from the rear end hitting claw HP sensor 326.

  As shown in FIG. 8, the saddle stitched sheet bundle S is a position where the middle folding position corresponds to the folding plate 74 with the movement of the movable rear end fence 73 while the pressure of the lower bundle conveying roller 72 is released. Then, as shown in FIG. 9, the vicinity of the bound needle portion is pushed in a substantially right angle direction by the folding plate 74, and opposing folding rollers (pair) 81 arranged in the advancing direction of the folding plate 74. Led to the nip. The folding roller (pair) 81 that has been rotated in advance holds the pressed sheet bundle S, and folds the sheet bundle at the center by carrying it under pressure. When the saddle-stitched sheet bundle S is moved upward for folding processing, the sheet bundle S can be reliably conveyed only by moving the movable rear end fence 73.

  As shown in FIG. 10, the folded sheet bundle S is reinforced by the second folding roller 82 and discharged to the lower tray 203 by the lower discharge roller 83. At this time, when the rear end of the sheet bundle is detected by the folding portion passage sensor 323, the folding plate 74 and the movable rear end fence 73 are returned to the home position, and the pressurization of the lower bundle conveying roller 72 is also restored, so that the next sheet is restored. Prepare for the import of. If the next job has the same sheet size and the same number of sheets, the movable rear end fence 73 may move again to the position shown in FIG. Further, the paper discharge sensor 324 detects the rear end of the sheet bundle S, and detects the discharge state of the sheet bundle S to the lower tray 203.

  FIG. 11 is a block diagram showing a control configuration of the entire system according to the present embodiment. As shown in FIG. 11, the control circuit 350 of the sheet post-processing apparatus PD is a microcomputer having a CPU 360, an I / O interface 370, and the like, each switch of the operation panel 380 of the image forming apparatus PR main body, and a paper surface detection sensor. A signal from each sensor such as 330 is input to the CPU 360 via the I / O interface 370. Based on the input signal, the CPU 360 moves a tray raising / lowering motor for the shift tray 202, a discharge guide plate opening / closing motor for opening / closing the opening / closing guide plate, a shift motor for moving the shift tray 202, and a return roller motor for driving the return roller 12. , Solenoids such as hitting SOL, a conveyance motor for driving each conveyance roller, a sheet discharge motor for driving each sheet discharge roller, a discharge motor for driving the discharge belt 52, a stapler moving motor for moving the end surface binding stapler S1, and end surface binding An oblique motor that rotates the stapler S1 obliquely, a jogger motor that moves the jogger fence 53, a bundle branching drive motor that rotates the guide member 44, a bundle conveyance motor that drives the conveyance roller 56 that conveys the sheet bundle S, and a movable rear end Rear end fence moving motor for moving the fence 73, folding plate Folding plate driving motor to move the 4 controls the drive such as the folding roller drive motor for driving the folding rollers 81. A pulse signal of a not-shown staple conveyance motor that drives the staple discharge roller is input to the CPU 360 and counted, and the hitting SOL 170 and the jogger motor 158 are controlled according to this count.

  The CPU 360 reads program code stored in a ROM (not shown), develops it in a RAM (not shown), and uses the RAM as a work area based on the program indicated by the program code. .

  12 and 13 are operation explanatory diagrams for explaining the folding operation. In the present embodiment, as shown in FIG. 1, a folding increase roller 520 is provided between the first folding roller 81 and the second folding roller 32. The folding roller 520 moves in a direction perpendicular to the sheet conveying direction in the same manner as the folding roller in the inventions described in the above cited documents 1 to 3, and performs additional folding.

  12 is a front view showing a state at the start of folding in two, and FIG. 14 is a plan view of the mechanism shown in FIG. However, the folding increase roller 520 is located at the maximum movement position. With reference to these two drawings, a mechanism related to the folding portion 525 will be described.

  The folding portion 525 includes a folding roller 520, a compression spring 521, and a slider 522. The slider 522 is a pair of guide rods provided between the front plate and the rear plate of the apparatus and perpendicular to the sheet conveying direction. It is supported so as to be movable along 526. Further, the folding roller 520 rolls in a state where a predetermined pressure is applied by the compression spring 521. That is, the middle folding processing unit includes a double folding unit including the first folding roller 81 and the folding plate 74, a folding unit 525 including a roller 520 for performing folding, and a second folding roller 83.

  The folding increase portion 525 is folded by a folding roller 520 that scans the fold portion of the sheet bundle S in a direction orthogonal to the sheet conveyance direction. This folding is performed by applying pressure to the folding roller 520 by an elastic member, here, a compression spring 521, and moving the slider 522 along the guide rod 526 on the fold of the sheet bundle S while being pressurized, This is done by strengthening the crease by the pressure applied by the spring 521. The folding roller 520 can pressurize the sheet bundle S by sandwiching the sheet bundle S with a guide plate 528 having a sheet receiving surface provided on the downstream side of the first folding roller 81 in the sheet conveying direction. It has become.

  Furthermore, a drive mechanism 501 is provided on the upper portion of the folding portion 525 to drive the folding roller 520 and simultaneously perform the separating operation of the lower bundle conveying rollers 72a and 72b. The drive mechanism 501 includes a pressure release motor 510, a pressure release gear 512, a folding roller driving gear 519, and a folding roller driving pulley 514 (a driving pulley and a driven pulley). The pressure release gear 512 obtains a driving force by a drive transmission belt 515 stretched between a pulley mounted on the rotation shaft of the pressure release motor 510 and the drive transmission gear 511, and the pressure release gear 512 via the relay gear 513. 512 is driven. Further, the roller drive gear 519 is engaged with the relay gear 513, and the roller release gear 512 and the roller drive gear 519 are rotationally driven by the drive of the pressure release motor 510.

  In the vicinity of the outer peripheral portion of the lower surface of the pressure release gear 512 in FIG. 12, one end swings to the central portion in the longitudinal direction of the driven shaft 403 of the bundle conveying roller lower 72b on the side where the first folding roller 81 of the bundle conveying roller 72 is disposed. The other end side of the lever 512a rotatably supported is pivotally supported. As a result, as the pressure release gear 512 rotates, the driven shaft 403 performs a reciprocating linear motion with respect to the lower bundle conveyance roller 72a, and approaches the sheet bundle S carried into the saddle stitching processing tray G. Separation is possible. One end of the elastic means, here, the compression spring 401 is fixed to the fixing plate 402 in order to give the conveying force to the sheet bundle S sandwiched between the approaching / separating operation and the lower nip between the bundle conveying rollers 72a and 72b. The end elastically biases the driven shaft 403 toward the side where the lower bundle conveying rollers 72a and 72b are close to each other. In FIG. 14, since the compression spring 401 elastically biases both ends of the driven shaft 403, the compression springs are denoted by reference numerals 401a and 401b, and the fixing plates are denoted by reference numerals 402a and 402b, respectively.

  On the other hand, a fold-up roller drive belt 517 is stretched between the fold-up roller drive gear 519 and the fold-up roller drive pulley 514, and the driving force of the pressure release motor 510 is fold-up and transmitted to the roller drive pulley 514. A folding roller driving belt 516 is further stretched between the folding roller driving pulley 514 and the folding roller driven pulley, and a slider 522 for supporting the folding roller 520 is attached to the folding roller moving belt 516. Yes. Therefore, the folding roller moving belt 516 is stretched so as to be parallel to the guide rod 526, and the relative positions of the folding roller driving pulley 514 and the folding roller driven pulley are defined so as to be parallel to the guide rod 526. ing.

  In the half-folding processing unit configured as described above, the lower bundle conveyance roller 72b is not shown in the figure, but moves close to and away from the bundle conveyance roller 72a, and the sheet bundle S is moved along the saddle stitching processing tray G. A pressure releasing operation is performed during conveyance, and the folding increase roller 520 performs an additional folding operation by moving in a direction substantially perpendicular to the sheet conveyance direction. That is, during the period from FIG. 12 to FIG. 13, as shown in FIG. 7 and FIG. 8, the operation of separating the lower bundle conveying roller 72b from the lower bundle conveying roller 72a is performed, and the sheet bundle S between the lower bundle conveying rollers 72a and 72b. In the state where the restriction is released, the folding operation is performed by the folding plate 74 and the folding roller 81.

  As described above, the lower bundle conveying roller 72b and the folding roller 520 are driven by the pressure release motor 510, and the drive is transmitted from the drive transmission belt 515 to the drive transmission gear 511. The transmitted driving force is transmitted from the relay gear 513 to the pressure release driving gear 512 and transmitted to the roller driving gear 519, and further increased via the additional roller driving transmission belt 517 to further transmit the driving force to the roller driving pulley 514. The folding roller moving belt 516 operates. Finally, the folding roller 520 is driven by the folding roller moving belt 516.

  The positional relationship between the folding roller 520 and the lower bundle conveyance roller 72b is such that when the folding roller 520 is at the home position or the maximum movement position, the pressure on the lower bundle conveyance roller 72 is released. Yes. This is because a sheet jam occurs when the folding roller 520 is positioned in the conveyance range of the sheet bundle S while the first folding roller 81 is performing the folding operation.

  12 shows a state in which the sheet bundle S is conveyed downward on the saddle stitching processing tray G, and FIG. 13 shows that the folding is performed by the folding plate 74 and the first folding roller 81, and the folding roller 520 is folded. This shows a state where the augmentation process has been completed.

  FIGS. 15 to 17 are diagrams showing a configuration and an operation pattern of the guide plate 528 at a position facing the additional folding roller 525. In FIG. 15, when the folded sheet bundle further enters the vicinity of the folding portion, the guide plate 528 maintains the position parallel to the sheet surface, and the X direction (folding roller 520 is orthogonal to the sheet conveying direction). The distance L is moved in the direction away from the head. The guide plate 528 is moved by a motor and a drive mechanism (not shown). The drive mechanism supports the guide plate 528, guides the movement of the guide plate 528 in the X direction, and decelerates the driving force of the motor (stepping motor) and transmits it to the guide plate 528. The guide member And a drive mechanism for moving the guide plate 528 in the X direction.

  In this embodiment, as shown in FIG. 18, a pin 528 a provided at a position shifted from the rotation center of the side surface of the pulley 529 is loosely fitted into a long hole provided horizontally at the falling portion of the guide plate 528, and the pulley In 529, the rotational movement is converted into the vertical movement of the guide plate 528.

  The pulley 529 is a driven pulley, and a driving force is transmitted by the motor 530 via a timing belt 529a stretched between the pulley 529 and a driving pulley 530a provided on a driving shaft of the motor 530. As a result, the guide plate 528 reciprocates in the vertical direction while the motor 530 reciprocates.

  The drive mechanism has a mechanical configuration, and is not particularly limited as long as the drive force of the motor can be converted into the movement of the guide plate 528. For example, the cam mechanism, the link mechanism, etc. can be a gear mechanism or a timing belt. It can be driven using the mechanism and moved up and down. The motor is controlled by the CPU 360.

  When the guide plate 528 does not move, when a thick sheet bundle or a sheet bundle whose folds are not strengthened before the additional folding enters the additional folding portion, the load increases due to resistance due to the thickness, but the guide plate 528 moves. This reduces the resistance of the sheet bundle and reduces the load. That is, in the additional folding roller 525, the roller portion 520 escapes upward by the spring 521, so that it can cope with a certain thickness, but when it is too thick, it cannot cope with the escape of the roller portion 520 alone. FIG. 18 is a diagram showing a state when a thick sheet bundle is folded. For example, as shown in FIG. 18 (a-1), when the relief of the roller 520 is r and the thickness of the sheet bundle is p, if the value of the thickness p is too large with respect to the value of the relief r, the additional folding roller When 525 collides with the sheet bundle and rides on, the load may become excessive, causing the motor to step out and damage the sheet bundle. At this time, the drive mechanism has the positional relationship shown in FIG.

  However, as shown in FIGS. 18B-1 and 18B-2, if the guide plate 528 is moved downward from the initial position by the distance L and the ride height is adjusted, the difference in height when riding up is adjusted. Is reduced and the load is not excessive. Therefore, the motor step-out and the sheet bundle are not damaged. Then, after getting on, additional folding can be performed as shown in FIG. The state of the drive mechanism at this time is as shown in FIG.

  Returning to the explanation of the operation after FIG. 15, when the sheet bundle reaches the additional folding portion in FIG. 16, the sheet bundle stops, and the additional folding roller 525 moves in a substantially perpendicular direction so as to follow the folded position of the stopped sheet bundle. Scan. This state is shown in FIG. FIG. 19A shows a state immediately before riding on a fold to be folded, FIG. 19B shows a straight line state after riding and starting to fold, and FIG. 19C continues folding. Each state is shown. When the additional folding is completed, the sheet bundle is conveyed downstream, and the guide plate 528 moves in the direction of the arrow X ′ (upward) as shown in FIG. 17 and returns to the original position. However, the sub guide plate 527 located on the downstream side of the guide plate 528 holds the position moved by the distance L in the arrow X direction before the conveyance of the sheet bundle is finished. After passing, it moves to the initial position (position before moving) in the same manner as the guide plate 528.

  FIG. 20 is a flowchart showing a control procedure of the CPU 360 for determining the movement amount L of the guide plate 528, or conversely, the ride height. In the figure, the thickness of the folded bundle is thicker as the sheet is thicker and thicker as the number of sheets is larger. Also, the smaller the sheet size, the harder it is to crease and the thicker it is. Therefore, the positional relationship between the additional folding roller 525 and the guide plate 528 can be optimized by changing the moving amount L of the guide plate 528 depending on the thickness, number of sheets, and size of the sheet.

In this flowchart, first, sheet type information (S1), sheet size information (S2), and sheet number information (S3) are acquired (steps P101, P102, P103). When these pieces of information are acquired, from the sheet type information, size information, and sheet number information, as shown in the table of FIG. 21, based on the determination and processing shown in steps P104 to P118,
1) If plain paper, small size, less than 15 sheets, L = L1 and 5mm
2) For plain paper, small size, 15 sheets or more, L = L2 and 7 mm
3) If plain paper, large size, less than 15 sheets, L = L3 and 3 mm
4) If plain paper, large size, 15 sheets or more, L = L4 and 5mm
5) If thick paper, small size, less than 15 sheets, 7mm as L = L5
6) For thick paper, small size, 15 sheets or more, L = L6 and 10 mm
7) If thick paper, large size, less than 15 sheets, L = L7 and 5 mm
8) For thick paper, large size, 15 sheets or more, L = L8 and 3 mm
Set as Whether the paper is thick paper or plain paper is determined in step P104, the size is determined in steps P105 and P112, the number of sheets is determined in steps P106, P109, P113, and P116. This is performed at P108, P110, P111, P114, P115, P117, and P118.

  The specific value of the movement amount is a value that can be appropriately set according to the roller diameter of the folding roller 525 and the characteristics of the device, and the value is an example.

  In the flowchart of FIG. 20, the thickness of the sheet is thick paper (70 kg paper or more) and plain paper, the number of sheets is less than 15 sheets and 15 sheets or more, and the sheet size is smaller than A4 and larger than A4. In FIG. 8, both are set to 2 levels, but may be 3 levels or more, and these can be arbitrarily set.

As described above, according to the present embodiment,
1) Since the folded portion of the sheet that has been folded once is creased and re-pressed by the roller 520, the fold can be strengthened and a beautiful finish without thickness can be achieved.
2) By moving the guide plate 528, re-pressurization can be performed with the positional relationship between the folding roller 528 and the guide member 528 being in an optimum state regardless of the thickness of the sheet bundle.
3) Since the movement amount L of the guide plate 528 is changed according to at least one element of the thickness (type), number of sheets, and size of the sheet, the folding increase condition can be set optimally.
4) Since the guide plate 528 is folded before the folding operation, when the sheet bundle further enters the folding section, the guide plate 528 is moved to an optimal position for folding, and the folding operation is appropriately performed. It becomes possible.
5) Since the guide plate 528 returns to the original position after the folding operation is completed, it is possible to immediately cope with the folding operation for the next sheet.
There are effects such as.

  Needless to say, the present invention is not limited to this embodiment, but covers all technical matters included in the technical idea defined in the scope of claims.

FIG. 2 is a diagram for explaining a system including a sheet post-processing apparatus PD and an image forming apparatus PR according to an embodiment of the present invention. It is a front view which shows an end surface binding processing tray and a saddle stitching processing tray. FIG. 11 is an operation explanatory diagram (part 1) in the saddle stitch binding mode; FIG. 11 is an operation explanatory diagram (part 2) in the saddle stitch binding mode; FIG. 11 is an operation explanatory diagram (part 3) in the saddle stitch binding mode; FIG. 12 is an operation explanatory diagram (part 4) in the saddle stitch binding mode; FIG. 11 is an operation explanatory diagram (part 5) in the saddle stitch binding mode; FIG. 11 is an operation explanatory diagram (part 6) in the saddle stitch binding mode; FIG. 10 is an operation explanatory diagram (part 7) in the saddle stitch binding mode; FIG. 10 is an operation explanatory view (No. 8) in the saddle stitch binding mode. It is a block diagram which shows the control structure of the whole system which concerns on this embodiment. It is operation | movement explanatory drawing which shows operation | movement of the state just before the start of folding operation | movement of a folding roller. It is operation | movement explanatory drawing which shows the state immediately before performing a middle fold with a folding roller and performing a folding increase with a folding roller. It is a top view which shows the drive mechanism under a folding roller and a bundle conveyance roller. It is operation | movement explanatory drawing which shows the operation | movement (state at the time of middle folding) of the folding part which concerns on this embodiment. It is operation | movement explanatory drawing which shows the operation | movement (state at the time of folding) of the folding part which concerns on this embodiment. It is operation | movement explanatory drawing which shows the operation | movement (state at the time of completion | finish of folding) of the folding part concerning this embodiment. It is operation | movement explanatory drawing which shows operation | movement of the guide plate of the folding part which concerns on this embodiment. It is operation | movement explanatory drawing which shows the operation | movement of folding operation | movement. It is a flowchart which shows the control procedure which determines the moving amount | distance of a guide plate. FIG. 10 is a table showing the relationship between the type, size, number of sheets, and movement amount of a sheet.

Explanation of symbols

74 Folding plate 81 First folding roller 360 CPU
520 Additional roll 521 Compression spring 522 Slider 525 Additional section 526 Guide rod 528 Guide plate PD Paper post-processing device PR Image forming device

Claims (10)

Folding means for performing folding processing on the sheet or sheet bundle after image formation;
Folding means for moving along the folds of the sheet or sheet bundle folded by the folding means and repressurizing the folds to strengthen the folds;
In a sheet folding apparatus comprising:
A guide member that receives the pressure applied by the folding means via a sheet or a sheet bundle;
Moving means for moving the guide member in a direction perpendicular to the sheet conveying direction;
The moving means moves the guide member away from the folding means when the folding means re-pressurizes the crease, and rides on the end of the sheet bundle. A sheet folding device characterized by adjusting the thickness. The sheet folding apparatus according to claim 1, wherein
A sheet folding apparatus, comprising: a setting unit configured to set an amount of movement of the guide member by the moving unit based on at least one of the thickness, size, and number of sheets of the sheet. The sheet folding apparatus according to claim 1, wherein
The sheet folding apparatus, wherein the folding means includes a rolling member that rolls on the fold in a direction perpendicular to the sheet conveying direction along the fold. The sheet folding apparatus according to claim 1, wherein
The sheet folding apparatus, wherein the moving unit moves the guide member before a folding operation by the folding unit is started. The sheet folding apparatus according to claim 1, wherein
The sheet folding apparatus, wherein the moving unit moves the guide member to a position before the folding operation is started after the folding operation by the folding unit is completed.   A sheet processing apparatus comprising the sheet folding apparatus according to claim 1.   A sheet conveying apparatus comprising the sheet folding apparatus according to claim 1.   An image forming apparatus comprising the sheet folding device according to claim 1.   An image forming apparatus comprising the sheet processing apparatus according to claim 6.   An image forming apparatus comprising the sheet conveying device according to claim 7.

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