JP2013095582A - Sheet processing device, image forming system, and sheet processing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To secure excellent sheet alignment accuracy even if a placing means is reciprocated in a direction orthogonal to the sheet conveying direction to sort sheets.SOLUTION: A sheet processing device includes a shift tray 202 for placing conveyed sheets, a shift mechanism which sorts the sheets by reciprocating the shift tray 202 in a direction orthogonal to the sheet conveying direction, a pressing member 220 which presses rear ends in the conveying direction of the sheets to be placed on the shift tray 202, and a roller 228a which is provided on the pressing member 220 and rotatable in the direction orthogonal to the sheet conveying direction. The shift mechanism executes sorting operation while pressing the sheets via the roller 228a.

Description

  The present invention relates to a sheet processing apparatus, an image forming system, and a sheet processing method, and in particular, a sheet-like recording medium such as a loaded paper, a recording paper, a transfer paper, and an OHP sheet (in this specification, simply “sheet”). And a sheet processing method executed by the sheet processing apparatus, and an image forming system including the sheet processing apparatus and an image forming apparatus such as a copying machine, a printer, a facsimile, or a digital multifunction peripheral. .

Conventionally, a sheet processing apparatus that performs various processes on sheets discharged from the image forming apparatus, for example, post-processing such as alignment, binding, folding, and bookbinding, and here, a sheet post-processing apparatus that performs post-processing. The devices referred to are known and widely used. In recent years, the range of sheet handling capability required for this type of sheet post-processing apparatus has increased dramatically. In particular, in color image forming apparatuses, the ratio of printing on a coated sheet (hereinafter referred to as coated paper) on which images are reflected in catalogs, leaflets, etc. is high, but coated paper is generally 1) surface. High smoothness.
2) High adhesion between papers.
3) Clark steel is low.
It has the characteristics. Therefore, these characteristics may cause the coated paper loadability to deteriorate.

  In order to prevent such deterioration in stackability, a return roller for stacking discharged sheets at a normal position is used. Patent Document 1 (Japanese Patent Application Laid-Open No. 2004-284786) discloses a discharge tray that discharges sheets on which images are stacked and a rear end portion in the discharge direction of the sheets discharged on the discharge tray. In the paper stacking apparatus having a pressing member for holding the sheet, the discharge tray is configured to be offset by a predetermined amount in a direction orthogonal to the sheet discharging direction, and the pressing member is interlocked with the offset operation of the discharge tray. The invention is characterized in that it moves as described above.

  However, in the return roller, when the succeeding sheet is discharged, it is separated from the surface of the sheet, so that the succeeding sheet is brought into close contact with the preceding sheet due to static electricity, and the preceding sheet is pushed out by the succeeding sheet. It cannot be prevented. Similarly, when the paper discharge tray is shifted, the return roller is separated from the sheet, so that the aligned state cannot be maintained. On the other hand, if the return roller is in contact with the sheet during the shift operation, the sheet cannot be appropriately shifted due to friction between the return roller and the sheet, and the aligned state cannot be maintained. In any case, the sheet alignment accuracy cannot be maintained during the shift operation, and the sheet alignment accuracy may be deteriorated.

  In the invention described in Patent Document 1, since it is impossible to hold the sheets in the aligned state when the paper discharge tray is shifted, it has not been possible to prevent the alignment accuracy from being deteriorated.

  Therefore, the problem to be solved by the present invention is to ensure good sheet alignment accuracy even when the paper discharge tray is shifted.

  In order to solve the above-described problems, the present invention provides a stacking unit that stacks conveyed sheets, a sorting unit that reciprocates the stacking unit in a direction orthogonal to the sheet conveying direction, and a stacking unit on the stacking unit. A pressing unit that presses a rear end portion in the conveying direction of the sheets stacked on the sheet, and a rotating member that is provided in the pressing unit and is rotatable in a direction orthogonal to the sheet conveying direction. A sheet processing apparatus that performs a sorting operation in a state where a sheet is pressed through a rotating member is characterized.

  According to the present invention, even when the stacking unit reciprocates in the direction orthogonal to the sheet conveying direction for sorting, it is possible to ensure good sheet alignment accuracy.

1 is a system configuration diagram illustrating a system including a sheet post-processing apparatus and an image forming apparatus as a sheet processing apparatus according to an embodiment of the present invention. It is the schematic block diagram which looked at the end surface binding processing tray in FIG. 1 from the stacking surface side of the tray. It is a perspective view which shows schematic structure of the end surface binding processing tray in FIG. 1, and its attachment mechanism. It is a side view which shows operation | movement of the discharge | release belt in FIG. It is a principal part front view which shows the standby state of the shift tray in FIG. It is operation | movement explanatory drawing which shows the alignment operation | movement of the conveyance direction on a shift tray. FIG. 4 is a perspective view of a paper discharge unit including a shift tray and a paper discharge roller. FIG. 6 is a diagram illustrating an alignment operation in a sheet width direction on a shift tray. FIG. 6 is a diagram illustrating a state when a succeeding sheet is discharged in a state where a preceding sheet is stacked on a shift tray. FIG. 10 is a diagram illustrating a state when sticking due to close contact between sheets occurs from the state of FIG. 9 and a succeeding sheet pushes out a preceding sheet. It is a figure which shows the structure of the paper discharge part provided with the pressing member. FIG. 12 is a perspective view of FIG. 11. It is explanatory drawing which shows the outline | summary of operation | movement of a pressing member, and shows a state when a preceding sheet is discharged. It is explanatory drawing which shows the outline | summary of operation | movement of a press member, and after a preceding sheet | seat is discharged | emitted, a state when a succeeding sheet | seat is discharged | emitted is shown. It is a perspective view which shows the operation mechanism and operation | movement of a press member, and shows the state at the time of a return roller operation | movement. It is a perspective view which shows the operation mechanism and operation | movement of a press member, and is a figure which shows the state at the time of a press member operation | movement. It is a figure which shows the retracted position of a press member. It is a figure which shows the pressing position of a pressing member. It is a figure which shows the structure of the roller part of the front-end | tip of a press member. It is a top view which shows the state which the shift tray shifted in the state which the press member pressed the sheet | seat. FIG. 20 is an enlarged view of a main part in which a part surrounded by a circle in FIG. 20 is enlarged, and shows a state before and after the shift. 3 is a block diagram illustrating a control configuration of an image forming system including a sheet post-processing apparatus and an image forming apparatus. FIG.

  The present invention is characterized in that the sheet discharge tray (shift tray) can be shifted while the pressing means is pressing the sheet. Thereby, since it shifts in the pressed state, the alignment state of a sheet | seat is hold | maintained and favorable alignment accuracy can be obtained.

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

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

  In FIG. 1, an image forming apparatus PR is an image processing circuit that converts input image data into printable image data, and an optical writing apparatus 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 post-processing apparatus PD is attached to a 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 post-processing apparatus PD includes a conveyance path A, a conveyance path B, a conveyance path C, a conveyance path D, and a conveyance path H, and the sheet is a post-processing unit (in this embodiment) that performs post-processing on a single sheet. It is first transported to a transport path A having a punch unit 50) as a punching means.

  The conveyance path B is a conveyance path that leads to the upper tray 201 through the conveyance path A, and the conveyance path C is a conveyance path C that leads to the shift tray 202. The conveyance path D is a conveyance path D that leads to a processing tray F that performs alignment, stapling, and the like (hereinafter also referred to as an “end face binding processing tray”). The conveyance path A is distributed to the conveyance paths B, C, and D by the branch claw 15 and the branch claw 16, respectively.

  In this sheet post-processing apparatus, punching (punch unit 50), sheet alignment + edge binding (jogger fence 53, end surface binding stapler S1), sheet alignment + saddle binding (saddle stitch upper jogger fence 250a, Processing such as saddle stitching lower jogger fence 250b, saddle stitching stapler S2), sheet sorting (shift tray 202), center folding (folding plate 74, folding roller 81), and the like can be performed. Therefore, the transport path A and the subsequent transport path B, transport path C, and transport path D are selected according to the processing. Further, the conveyance path D includes a sheet storage portion E, and an end face binding processing tray F, a saddle stitching middle folding processing tray G, and a paper discharge conveyance path H are provided on the downstream side of the conveyance path D.

  A common conveyance path A upstream of the conveyance path B, the conveyance path C, and the conveyance path D includes an inlet sensor 301 that detects a sheet received from the image forming apparatus PR, and an inlet roller 1 and a punch unit 50 downstream of the sensor. The punch and waste hopper 50a, the conveying roller 2, the first and second branching claws 15, and the branching claws 16 are sequentially arranged. The first and second branch claws 15 and 16 are held in the state of FIG. 1 by a spring (not shown) (initial state), and the branch claws 15 and 16 are turned on by turning on the first and second solenoids (not shown). , Respectively, and the combination of the branch directions of the first and second branch claws 15 and 16 is changed by selecting ON / OFF of the first and second solenoids, the transport path B, the transport path C, The sheet is distributed to the conveyance path D.

When the sheet is guided to the conveyance path B, the state shown in FIG. 1, that is, the first solenoid remains OFF (the first branch claw 15 is in the initial state). As a result, the sheet is discharged 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 C, the first and second solenoids are turned on from the state shown in FIG. 1 (the second branch claw 16 is in the initial state), so that the branch claw 15 branches upward. The nail | claw 16 will be in the state which each rotated below. Thus, the sheet is conveyed to the shift tray 202 side through the conveying roller 5 and the discharge roller pair 6 (6a, 6b). In this case, the sheets are sorted. Sheet sorting is performed by reciprocating the shift discharge roller pair 6 (6a, 6b), the return roller 13, the paper surface detection sensor 330, the shift tray 202, and the shift tray 202 in a direction orthogonal to the sheet conveying direction. This is performed by a shift mechanism that does not, and a shift tray lifting mechanism that lifts and lowers the shift tray 202.

  When the sheet is guided to the conveying path D, the first solenoid that drives the first branch claw 15 is turned ON, and the second solenoid that drives the second branch claw is turned OFF, so that the branch claw 15 and the branch Both the claws 16 are rotated upward, and the sheet is guided from the conveying roller 2 to the conveying path D through the conveying roller 7. The sheet guided to the conveyance path D is guided to the end face binding processing tray F, and the sheet subjected to alignment, stapling, and the like in the end face binding processing tray F is guided to the shift tray 202 by the guide member 44. The sheet is fed to the saddle stitching / saddle folding processing tray G (hereinafter also simply referred to as “saddle stitching processing tray”). When guided to the shift tray 202, the sheet bundle PB is discharged from the discharge roller pair 6 to the shift tray 202. Further, the sheet bundle PB guided to the saddle stitching processing tray G side is folded and bound by the saddle stitching processing tray G, and is discharged from the discharge roller 83 to the lower tray 203 through the discharge conveyance path H. .

  On the other hand, 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. The sheet can be reversed along the turn guide 8 by reversing at least the conveyance roller 9 among the conveyance rollers 9 and 10 and the staple discharge roller 11. 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. Reference numeral 304 denotes a prestack sensor for setting a reverse feed timing when the sheets are prestacked.

  When the sheet is guided to the conveyance path D and sheet alignment and end binding are performed, the sheets guided to the end surface binding processing tray F by the staple discharge roller 11 are sequentially stacked on the end surface binding processing tray F. In this case, for each sheet, the tapping roller 12 and the rear end reference fence 51 are aligned in the vertical direction (sheet conveyance direction), and the jogger fence 53 is in the horizontal direction (also referred to as a direction perpendicular to the sheet conveyance direction—the sheet width direction). Are matched. The end face binding stapler S1 as the binding means is driven by a staple signal from the CPU 101 (to be described later) between the end of the job, that is, from the last sheet of the sheet bundle PB to the first sheet of the next sheet bundle, and the binding process is performed. The sheet bundle PB subjected to the binding process is immediately sent to the shift paper discharge roller 6 by the discharge belt 52 (see FIG. 2) on which the discharge claw 52a protrudes, and is discharged to the shift tray 202 set at the receiving position. Paper.

  As shown in FIGS. 2 and 4, the discharge belt 52 is positioned at the center of alignment in the sheet width direction, is stretched between pulleys 62, and is driven by a discharge belt drive motor 157. 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 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 PB accommodated in the end face binding processing tray F is moved and conveyed alternately. Further, if necessary, the discharge belt 52 is rotated in the reverse direction, and the sheet bundle stored in the end face binding processing tray F on the back surface of the discharge claw 52a opposite to the discharge claw 52a opposite to the sheet bundle PB. It is also possible to align the leading ends of the PB in the transport direction.

  In FIG. 1, reference numeral 110 denotes a rear end pressing lever, which is positioned at the lower end of the rear end reference fence 51 so that the rear end of the sheet bundle PB accommodated in the rear end reference fence 51 can be pressed. It reciprocates in a direction substantially perpendicular to the end face binding processing tray F. The sheets P discharged to the end-face binding processing tray F are tapped for each sheet and aligned in the vertical direction (sheet conveyance direction) with the roller 12, but the trailing edge of the sheets stacked on the end-face binding processing tray F is curled. If the waist is weak, the rear end tends to buckle and swell due to the weight of the seat itself. Further, as the number of stacked sheets increases, the gap for the next sheet in the rear end reference fence 51 is reduced, and the vertical alignment tends to be deteriorated. Therefore, the trailing edge pressing mechanism is configured to reduce the swelling of the trailing edge PT so that the sheet P easily enters the trailing edge reference fence 51, and directly pressing the sheet P or the sheet bundle PB is the trailing edge. A holding lever 110 is provided.

  In FIG. 1, reference numerals 302, 303, 304, 305, and 310 denote sheet detection sensors that detect whether or not a sheet has passed at a provided position or whether or not a sheet is stacked.

  FIG. 2 is a schematic configuration diagram of the end face binding processing tray F as viewed from the tray stacking surface side, and corresponds to the case of viewing from the right side surface of FIG. In the same figure, the alignment in the width direction of the sheet received from the upstream side image forming apparatus PR is performed by jogger fences 53a and 53b, and the vertical direction is on rear end reference fences 51a and 51b (indicated by reference numeral 51 in FIG. 1). It is abutted and aligned. The rear end reference fences 51a and 51b are respectively provided with stack surfaces 51a1 and 51b1 that hold the sheet rear end PT in contact with and hold the sheet rear end PT, and support the sheet rear end PT at two points. After completion of the alignment operation, binding processing is performed by the end-face binding stapler S1, and the discharge belt 52 is driven counterclockwise by the discharge belt drive motor 157, as can be seen from the perspective view showing the operation of the discharge belt in FIG. The sheet bundle PB after the binding process is lifted to a predetermined position by the rear end reference fences 51 a and 51 b, scooped by the discharge claw 52 a attached to the discharge belt 52, and discharged from the end face binding processing tray F. Reference numerals 64a and 64b are a front side plate and a rear side plate. Further, this operation can be performed in the case of an unbound bundle that is not subjected to the binding process after the alignment process.

  FIG. 3 is a perspective view showing a schematic configuration of the end face binding processing tray F and its attached mechanism. As shown in the drawing, the sheets P guided to the end-face binding processing tray F by the staple paper discharge roller 11 are sequentially stacked on the end-face binding processing tray F. At this time, when the number of sheets P to be discharged to the end face binding processing tray F is one, alignment in the vertical direction (sheet conveyance direction) is performed between the tapping roller 12 and the rear end reference fence 51 for each sheet. The jogger fences 53a and 53b perform alignment in the width direction (the sheet width direction orthogonal to the sheet conveyance direction). The hitting roller 12 is given a pendulum motion by the hitting SOL 170 about the fulcrum 12a, and intermittently acts on the sheet sent to the end-face binding processing tray F to abut the sheet rear end PT against the rear end reference fence 51. The hitting roller 12 itself rotates counterclockwise in the figure. The jogger fence 53 is provided with a pair of front and rear (53a, 53b) as shown in FIGS. 2 and 3, and is driven via a timing belt by a jogger motor 158 capable of forward / reverse rotation, and is symmetrically approached and separated in the seat width direction. So reciprocate.

  Returning to FIG. 1, a sheet bundle deflection mechanism is provided on the downstream side in the sheet conveyance direction of the end-face binding processing tray F. The conveying path for conveying the sheet bundle PB from the end-face stitching processing tray F to the saddle-stitching processing tray G, and from the end-face stitching processing tray F to the shift tray 202, and the conveying means for conveying the sheet bundle PB impart conveying force to the sheet bundle PB. A feeding mechanism 35 for feeding, a discharge roller 56 for turning the sheet bundle PB, and a guide member 44 for performing a guide for turning the sheet bundle PB.

  Each detailed configuration will be described. The driving force of the driving shaft 37 is transmitted to the roller 36 of the transport mechanism 35 by a timing belt. The roller 36 and the driving shaft 37 are connected and supported by an arm, and driven. The shaft 37 can be swung about the rotation fulcrum. The roller 36 of the transport mechanism 35 is driven to swing by a cam 40. The cam 40 rotates around a rotation shaft and is driven by a motor (not shown). In the transport mechanism 35, a driven roller 42 is disposed at a position opposite to the roller 36, the sheet bundle PB is sandwiched between the driven roller 42 and the roller 36, and is pressurized by an elastic material to give a transport force.

  A conveyance path for turning the sheet bundle PB from the end-face binding processing tray F to the saddle stitching processing tray G is formed between the discharge roller 56 and the inner surface of the guide member 44 facing the discharge roller 56. The guide member 44 rotates around a fulcrum, and the drive is transmitted from the bundle branch drive motor 161 (see FIG. 2). When the sheet bundle PB is conveyed from the end surface binding processing tray F to the shift tray 202, the guide member 44 rotates in the clockwise direction in the figure around the fulcrum, and the outer surface of the guide member 44 (on the side not facing the discharge roller 56). The space between the surface) and the guide plate outside thereof functions as a conveyance path. When the sheet bundle PB is sent from the end face binding processing tray F to the saddle stitching processing tray G, the trailing edge of the sheet bundle PB aligned on the end face binding processing tray F is pushed up by the discharge claw 52a, and the roller 36 of the transport mechanism 35 and this The sheet bundle PB is sandwiched between the opposed driven rollers 42 facing each other, and a conveying force is applied. At this time, the roller 36 of the transport mechanism 35 stands by at a position where it does not hit the leading end of the sheet bundle PB. Next, after the leading edge of the sheet bundle has passed, the roller 36 of the transport mechanism 35 is brought into contact with the sheet surface to apply a transport force. At this time, the guide member 44 and the discharge roller 56 form a guide for the turn conveyance path, and convey the sheet bundle PB to the downstream saddle stitching processing tray G.

  As shown in FIG. 1, the saddle stitch processing tray G is provided on the downstream side of the sheet bundle deflection mechanism including the conveyance mechanism 35, the guide member 44, and the discharge roller 56. The saddle stitching processing tray G is provided substantially perpendicularly on the downstream side of the sheet bundle deflection mechanism, with the center folding mechanism at the center, the bundle conveyance guide plate upper 92 above, and the bundle conveyance guide below. A lower plate 91 is arranged.

  Further, an upper bundle conveying roller 71 is provided above the upper bundle conveying guide plate 92, and a lower bundle conveying roller 72 is provided below the upper bundle conveying guide plate 92. A saddle stitch upper jogger fence 250a is arranged on both sides along the side surface of 92. Similarly, a saddle stitch lower jogger fence 250b is provided on both sides along the side surface of the bundle conveyance guide plate lower 91, and the saddle stitch stapler S2 is disposed at a place where the saddle stitch lower jogger fence 250b is installed. The saddle stitching upper jogger fence 250a and the saddle stitching lower jogger fence 250b are driven by a driving mechanism (not shown) and perform an alignment operation in a direction orthogonal to the sheet conveying direction (sheet width direction). The saddle stitching stapler S2 is a pair of a clincher portion and a driver portion, and two pairs are provided at a predetermined interval in the width direction of the sheet.

  In addition, a movable rear end reference fence 73 is disposed so as to cross the bundle conveyance guide plate lower 91, and can be moved in the sheet conveyance direction (vertical direction in the drawing) by a moving mechanism including a timing belt and its driving mechanism. Yes. As shown in FIG. 1, the drive mechanism includes a drive pulley and a driven pulley on which the timing belt is stretched, and a stepping motor that drives the drive pulley. Similarly, a rear end tapping claw 251 and its drive mechanism are provided on the upper end side of the upper bundle transport guide plate 92. The rear end tapping claw 251 can be reciprocated in a direction away from the sheet bundle deflection mechanism and a direction of pushing the rear end of the sheet bundle PB (the side hitting the rear end when the sheet bundle is introduced) by a timing belt 252 and a driving mechanism (not shown). It has become.

  The center folding mechanism is provided at a substantially central portion of the saddle stitching processing tray G, and includes a folding plate 74, a folding roller 81, and a conveyance path H that conveys the folded sheet bundle PB. In FIG. 1, reference numeral 326 denotes a home position sensor for detecting the home position of the rear end tapping claw 251, reference numeral 323 denotes a folded portion passage sensor for detecting a folded sheet, and reference numeral 321 denotes a sheet bundle PB. Bundle detection sensor 322 for detecting that has reached the center folding position, and reference numeral 322 is a movable rear end reference fence home position sensor for detecting the home position of movable rear end reference fence 73.

  In this embodiment, a detection lever 501 for detecting the stacking height of the sheet bundle PB folded in the lower tray 203 is provided to be swingable by a fulcrum 501a, and the angle of the detection lever 501 is determined by a paper surface sensor 505. Detecting and raising / lowering the lower tray 203 and detecting overflow.

  FIG. 5 is a front view of the main part showing the paper discharge unit of the shift tray 202, FIG. 5 (a) is a diagram showing a standby state during paper discharge, and FIG. 5 (b) is a circle in FIG. 5 (a). It is a figure which expands and shows the principal part of the part shown. As described above, the sheet is conveyed to the shift tray 202 side through the discharge roller pair 6 (6a, 6b), and the shift tray 202 sorts the sheet. As described above, the sheet sorting is performed by the shift discharge roller pair 6 (6a, 6b), the return roller 13, the shift tray 202, the shift mechanism, and the shift tray lifting / lowering mechanism.

  FIG. 6 is an operation explanatory view showing the alignment operation in the transport direction. In the aligning operation, after the sheet is discharged, the return roller 13 contacts the sheet P while rotating in the direction to return the sheet P toward the end fence 210 (arrow R1 direction), and positively returns the sheet P toward the end fence 210. It is done by doing. Although not shown here, the return roller 13 is driven by a return roller drive motor 223 described later, and the driving force is transmitted by a timing belt 13a (see FIG. 12).

  FIG. 7 is a perspective view of a paper discharge unit including a shift tray and a paper discharge roller. As can be seen from the figure, on the upper side of the shift tray 202, a pair of joggers 205a and 205b for aligning the sheets P in the width direction on the shift tray 202 are provided. The joggers 205a and 205b are movable in the width direction of the sheet P by the jogger driving mechanism 206. Note that the jogger drive mechanism 206 itself has a known structure, and the drive mechanism itself is not directly related to the present invention, so the details are omitted. In FIG. 5 and the like, reference numeral 202a denotes an escape portion (concave portion) for allowing the joggers 205a and 205b to move.

  FIG. 8 is a diagram illustrating an alignment operation in the sheet width direction on the shift tray 202. After the sheet is discharged, the width direction of the sheet P is aligned from the near side in the sheet width direction and from the far side by the near side jogger 205a and the far side jogger 205b. However, in the case of a sheet P with high smoothness such as coated paper, when the succeeding sheet P2 is discharged in a state where the preceding sheet P1 is stacked on the shift tray 202 as shown in FIG. Adhesion due to close contact occurs, and as shown in FIG. 10, the preceding sheet P1 is pushed out as it is in a state where the succeeding sheet P2 is in contact with the preceding sheet P1.

  In order to prevent the preceding sheet P1 from being pushed out, in the present embodiment, a pressing member is provided, and when the succeeding sheet P2 is discharged, the preceding sheet P1 is pressed by the pressing member.

  FIG. 11 is a diagram showing a configuration of a paper discharge unit provided with the pressing member 220, and FIG. 12 is a perspective view of FIG. FIG. 11 omits the shift tray 202 and shows a state viewed from the front side of the end fence 210, and the return roller 13 is arranged at the center of the upper end of the end fence 210. The return roller 13 includes a pair of roller members, and the pressing members 220 are provided on both sides (the front side and the back side as viewed from the front of the apparatus) with the return roller 13 interposed therebetween. The pressing member 220 performs a pressing operation only when the coated paper is passed from the image forming apparatus PR. Whether or not it is coated paper is notified from the CPU of the image forming apparatus PR described later to the CPU 101 of the sheet post-processing apparatus PD, and whether the operation of the pressing member 220 is determined based on the determination of the CPU 101.

  13 and 14 are explanatory views showing an outline of the operation of the pressing member 220. As shown in FIG. 13, the preceding sheet P1 is discharged to the shift tray 202, and after being stacked on the shift tray 202 as shown in FIG. 14, the conveying direction is aligned by the return roller 13, and the joggers 205a and 205b are aligned. The width direction is aligned by. When the alignment operation in the conveyance direction and the width direction is completed, the pressing member 220 presses the trailing edge of the preceding sheet P1 before the succeeding sheet P2 contacts the preceding sheet P1, as shown in FIG. When the sheet P2 is discharged and the sheet rear end PT passes through the sheet discharge roller 6, the pressing member 220 performs a retracting operation. The retreat operation is started by rotating the first shaft 221 in the reverse direction (in the direction of arrow R5) from the state shown in FIG. 18 described later, and returns to the retreat position shown in FIG. 17 described later.

  In terms of control, the pressing member 220 starts the pressing operation after the preceding sheet P1 is discharged to the shift tray 202 and completes the returning operation by the return roller 13, and the trailing end of the succeeding sheet P2 is shifted. The retraction operation is started before dropping onto the preceding sheet P1 stacked on the tray 202. The pressing operation and the retracting operation are executed by performing drive control of the return roller driving motor 223 by the CPU 101 described later. The start timing is also set by the CPU 101.

  15 and 16 are perspective views showing the operation mechanism and operation of the pressing member 220. FIG. 15 shows a state when the return roller is operating, and FIG. 16 shows a state when the pressing member is operating.

  The pressing member 220 is attached to the first shaft 221 in a state that allows rotation. A cam 222 is coaxially attached to the first shaft 221. The pressing member 220 is driven by the cam 222 and can move between a pressing position and a retracted position. The first shaft 221 rotates with the driving force transmitted through the gear reduction mechanism 223a with the return roller drive motor 223 as a drive source. At this time, after completion of the return operation of the return roller 13, the return roller drive motor 223 rotates reversely, and the pressing member 220 is rotationally driven in synchronization with the rotation of the cam 222 to perform the sheet pressing operation. The pressing operation and the retracting operation are performed only by reverse rotation of the return roller driving motor 223.

  In addition, the second shaft 224 is disposed in parallel with the first shaft 221, and the first gear 225 including the one-way clutch that locks the first and second shafts 221 and 224 in the opposite directions to each other, Gears 226 are respectively attached. A third gear 227 is further fixed to the second shaft 224, and rotates together with the rotation of the second shaft 224. Since the cam 221 is not fixed around the axis of the first shaft 221, only when the third gear 227 rotates, the cam 221 rotates integrally with the fourth gear 222a integrated with the cam 221 that meshes with the third gear 227. To do.

  When the return roller 13 is operated, the return roller drive motor 223 rotates forward (in the direction of arrow R2) as shown in FIG. Due to the one-way clutch, the first shaft 221 rotates, but the first gear 225 does not rotate, so the second shaft 224 remains stopped, and the third gear 227 and the cam 222 do not rotate, so the pressing member 220 does not rotate. Remains separated from the sheet P.

  15 and 16, the return roller 13 is not shown, but the return roller 13 is provided on a protruding portion that protrudes from the first shaft 221 between the pair of pressing members 220.

  When the pressing member 220 is operated, as shown in FIG. 16, the return roller drive motor 223 rotates in the reverse direction (in the direction of arrow R3), and the first and second gears 225 and 226 rotate. Due to the one-way clutch, the first shaft 221 stops and the second shaft 222 rotates. As a result, the third gear 227 rotates in the direction opposite to the rotation direction of the return roller drive motor 223 (the direction of the arrow R4), and the cam 222 that rotates integrally with the gear meshing with the gear 227 rotates in the direction of the arrow R5. . The pressing member 220 is operated by the rotation of the cam 222.

  FIG. 17 is a diagram illustrating the retracted position of the pressing member 220, and FIG. 18 is a diagram illustrating the pressing position of the pressing member 220. The pressing member 220 is rotatably supported by the rotating shaft 220b, and an elastic force is always applied in the retracting direction by the tension spring 229. As a result, the cam 222 moves away from the large diameter portion of the cam 222 and moves in the direction in which the sheet P is pressed (in the direction of arrow R6) only when the cam 222 is pushed out by the tension spring 229.

  That is, the retracted position is the position shown in FIGS. 15 and 17, and when the return roller drive motor 223 rotates in the reverse direction (arrow R4 direction) as shown in FIG. 16 from this position, the cam as shown in FIG. The fourth gear 222a that drives 222 rotates in the direction of arrow R5, and the cam 222 integrally rotates in the direction of arrow R5. When the cam 222 is removed from the large diameter portion of the cam 222 from the cam follower 220a provided on the pressing member 220, the pressing member 220 rotates in the sheet pressing direction (arrow R6 direction) and is positioned at the pressing position shown in FIG. . In this state, the roller 228a comes into contact with the surface of the sheet P or the sheet bundle PB, and the sheet P or the sheet bundle PB is pressed.

  Further, the proximal end side of the pressing member 220 is formed in a filler shape 220c, the home position (retracted position) is detected by the transmission type sensor SE1, and notified to the CPU 101 described later. The CPU 101 stops the reverse rotation driving of the return roller driving motor 223 based on the detection result, and starts control of the next operation.

  FIG. 19 is a view showing the structure of the roller portion 228 at the tip of the pressing member 220. The pressing member 220 is provided with a roller 228a at the tip, and the roller 228a presses the sheet P or the sheet bundle PB. However, the pressing member 220 is rotatable in the width direction of the sheet P around the shaft 228b so as not to become a resistance during the shift operation. ing. In other words, the axis of the rotation axis is parallel to the sheet conveying direction. More specifically, the roller portion 228 includes a shaft 228b and a low friction material roller 228a. The roller 228a is attached to the distal end side of the shaft 228b in a so-called loose fit state, and the base end side of the shaft 228 is press-fitted into the mounting hole 220c of the pressing member 220a, and is attached in a so-called tight fit state. At this time, a step is provided on the inner peripheral surface of the roller 228a and the outer peripheral surface of the shaft 228b, and the roller 228a cannot be detached from the shaft 228b by this step.

  FIG. 20 is a plan view showing a state where the shift tray 202 is shifted while the pressing member 220 presses the sheet, and FIG. 21 is an enlarged view of a circled portion in FIG. 21A shows the initial state, and FIG. 21B shows the state after the shift operation shifted from the initial state in the sheet width direction (arrow D1 direction).

  With this configuration, as shown in FIGS. 13 and 14, the preceding sheet P1 is returned by the return roller 13, and the width direction is aligned by the joggers 205a and 205b, and then pressed by the pressing member 220. The operation of discharging the sheet P2 in the row is repeated for one sheet bundle, and the final sheet of the one sheet bundle PB is discharged and shifted as shown in FIG. Operation is performed.

  At this time, the roller 228a of the low friction member shown in FIG. 19 is attached to the tip of the pressing member 220. When the shift tray 202 shifts while the sheet P is pressed, the roller 228a rotates and the width of the sheet It is possible to shift while maintaining the alignment accuracy of the direction.

  FIG. 22 is a block diagram illustrating a control configuration of an image forming system including the sheet post-processing apparatus PD and the image forming apparatus PR. The sheet post-processing apparatus PD includes a control circuit on which a microcomputer having a CPU 101, an I / O interface 102, and the like is mounted. The CPU 101 includes a CPU of the image forming apparatus PR or switches of the operation panel 105, and sensors (not shown). Is input via the communication interface 103, and the CPU 101 executes predetermined control based on the input signal. Further, the CPU 101 drives and controls a solenoid and a motor via a driver and a motor driver, and acquires sensor information in the apparatus from the interface. In addition, motor drive control is performed by the motor driver via the I / O interface 102 in accordance with the control target and sensor, and sensor information is acquired from the sensor. The control is based on a program defined by the program code while the CPU 101 reads a program code stored in a ROM (not shown), expands it in a RAM (not shown), and uses the RAM as a work area and a data buffer. Executed.

  Further, the control of the sheet post-processing apparatus PD in FIG. 22 is executed based on an instruction or information from the CPU of the image forming apparatus PR. User operation instructions are issued from the operation panel 105 of the image forming apparatus PR, and the image forming apparatus PR and the operation panel 105 are connected to each other via a communication interface 106. As a result, an operation signal from the operation panel 105 is transmitted from the image forming apparatus PR to the sheet post-processing apparatus PD, and the processing state and functions of the sheet post-processing apparatus PD are transmitted to the user or the operator via the operation panel 105 Be notified.

  Accordingly, when sort (sorting) is selected from the operation panel 105 of the image forming apparatus PR, for example, the CPU of the image forming apparatus PR instructs the CPU 101 of the sheet post-processing apparatus PD to perform sorting. The parts will be sorted. At this time, when coated paper is selected as information indicating the type of sheet, the pressing member 220 performs a pressing operation on the preceding sheet P1 during the shift operation, thereby preventing the preceding sheet P1 from being pushed out by the succeeding sheet P2. To do. Then, the shift operation is performed in the pressed state. The control during this time is executed by the CPU 101 of the sheet post-processing apparatus PD.

As described above, according to the present embodiment,
1) During the shift operation, the pressing member 220 performs a pressing operation on the preceding sheet P1, and the preceding sheet P1 is prevented from being pushed out by the succeeding sheet P2, so that the coated paper is prevented from being pushed out due to static electricity.
2) Since the roller portion 228 is provided at the tip of the pressing member 220, and the roller 228a of the roller portion 228 is rotatably attached to a shaft 228b provided in parallel with the sheet conveying direction, the pressing member 220 is attached to the sheet bundle PB. Even if the shift tray 202 shifts in the sheet width direction while pressing the upper surface of the sheet, the shift is performed while pressing the sheet bundle PB, so that good alignment accuracy can be maintained.
There are effects such as.

  It should be noted that the sheet in the claims is denoted by P, the stacking means is in the shift tray 202, the sorting means is in a shift mechanism and shift tray lifting mechanism (not shown), the pressing means is in the pressing member 220, the rotating member is in the roller 228a, The driving means includes first and second shafts 221 and 224, a first gear 225, a second gear 226, a third gear 227, a fourth gear 222a, a cam 222, a cam follower 220a, a return roller driving motor 223, The gear reduction mechanism 223a and the CPU 101, the return roller is denoted by reference numeral 13, the driving force connecting / disconnecting means is a one-way clutch (not shown), the setting means is CPU 101, the preceding sheet is P1, the succeeding sheet is P2, The bundle corresponds to the symbol PB, the sheet processing device corresponds to the sheet post-processing device PD, and the image forming device corresponds to the symbol PR.

  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 embodiment shows a preferable example, but those skilled in the art can realize various alternatives, modifications, variations, and improvements from the contents disclosed in this specification, These are included in the technical scope described in the appended claims.

13 Return roller 101 CPU
202 Shift tray 220 Press member 220a Cam follower 221 First shaft 222 Cam 222a Fourth gear 223 Return roller drive motor 223a Gear reduction mechanism 224 Second shaft 225 First gear 226 Second gear 227 Third gear 228a Roller P Sheet P1 Preceding sheet P2 Subsequent sheet PB Sheet bundle PD Sheet post-processing device (sheet processing device)
PR image forming device

JP 2004-284786 A

Claims (8)

A stacking means for stacking the conveyed sheets;
Sorting means for reciprocating the stacking means in a direction perpendicular to the sheet conveying direction and sorting;
A pressing unit that presses a rear end portion in a conveyance direction of the sheets stacked on the stacking unit;
A rotating member provided in the pressing means and rotatable in a direction orthogonal to the sheet conveying direction;
With
The sheet processing apparatus according to claim 1, wherein the sorting unit performs a sorting operation in a state where the sheet is pressed through the rotating member. The sheet processing apparatus according to claim 1,
A sheet processing apparatus comprising a driving unit that repeats the pressing operation of the pressing unit for each stacked sheet. The sheet processing apparatus according to claim 1 or 2,
The pressing means includes a plurality of pressing members, a cam coaxially connected to a first shaft for driving the plurality of pressing members, and a cam driving first gear rotatably mounted about the axis. ,
The driving means includes a second gear that meshes with the first gear and is provided coaxially with a second shaft disposed in parallel with the first shaft, and rotates integrally with the shaft.
The sheet processing apparatus, wherein the pressing member is movable between a pressing position and a retracted position by an operation of the cam. The sheet processing apparatus according to claim 3,
A return roller that is provided on the first shaft coaxially with the cam and returns the sheets stacked on the stacking means;
A drive source for rotationally driving the first shaft;
When the driving force from the driving source is rotated in the returning direction by the return roller, the transmission of the driving force to the second shaft is cut off, and when the driving force is rotated in the direction opposite to the returning direction, the second Driving force connecting / disconnecting means for transmitting driving force to the shaft of
With
The sheet processing apparatus according to claim 1, wherein the cam is driven only when the return roller rotates in the reverse direction. The sheet processing apparatus according to claim 4,
The driving means starts the pressing operation of the pressing member after the preceding sheet is discharged to the stacking means and is completed by the return roller, and the trailing end of the succeeding sheet is discharged to the stacking means. A sheet processing apparatus, wherein the retraction operation of the pressing member is started before dropping onto the sheet. The sheet processing apparatus according to any one of claims 1 to 5,
A sheet processing apparatus, comprising: a setting unit configured to set whether to operate the pressing unit based on information indicating a type of the stacked sheets. An image forming system comprising the sheet processing apparatus according to claim 1. A stacking means for stacking the conveyed sheets;
A pressing unit that presses a rear end portion in the conveyance direction of the sheets stacked on the stacking unit;
A sheet processing method for performing sorting by reciprocating the stacking unit in a direction orthogonal to the sheet conveying direction when stacking the sheet on the stacking unit,
A step of pressing a sheet stacked on the stacking unit by a rotating member that is rotatable in a direction orthogonal to the sheet conveying direction and provided in the pressing unit;
In a state where the sheet bundle is pressed by the rotating member in the pressing step, the stacking means is reciprocated in a direction orthogonal to the sheet conveying direction, and sorting is performed;
A sheet processing method comprising: