JP2018111594A - Sheet alignment device, sheet processing device, and image formation device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve alignment property of a sheet bundle with a configuration provided with a sheet holding means capable of holding a part of the sheet bundle.SOLUTION: A sheet alignment device (210) comprises an alignment rotating body (206) which rotates while contacting to a top face of a sheet held by a sheet loading part (213) and a sheet holding means (230, 240) and moves the sheet toward a contact part (212) for alignment. When a new sheet is ejected to the sheet loading part (213) in a state where a first number of sheets are loaded on the sheet loading part (213), a first alignment process for aligning a sheet position by rotary-driving the alignment rotating body (206) by a first rotation amount is executed. Further, when a new sheet is ejected to the sheet loading part (213) in a state where sheets of a second number larger than the first number are loaded on the sheet loading part (213), a second alignment process for rotary-driving the alignment rotating body by a second rotation amount larger than the first rotation amount is executed.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a sheet aligning apparatus that aligns a plurality of sheets to form a sheet bundle, and a sheet processing apparatus and an image forming apparatus including the sheet aligning apparatus.

  In a sheet aligning apparatus capable of forming a sheet bundle by aligning a plurality of sheets, in addition to the sheet stacking unit on which at least a part of the sheet bundle is stacked, the other part of the sheet bundle is supported together with the sheet stacking unit. Some have a member for holding a sheet bundle. Patent Document 1 discloses an intermediate stacking tray on which sheet bundles are stacked, a pair of alignment units that hold the sheet bundle downstream of the intermediate stacking tray in the sheet transport direction, and a transport direction alignment provided above the intermediate stacking tray. A sheet processing apparatus having a unit is described. Each of the pair of alignment portions includes a support portion that supports the lower surface of the sheet bundle, an upper restriction portion that can restrict the jumping of the side end of the sheet bundle, and a vertical portion that connects the support portion and the upper restriction portion. Hold both sides of the sheet bundle. The conveyance direction alignment unit moves the uppermost sheet of the sheet bundle held by the intermediate stacking tray and the pair of alignment units toward the alignment reference wall by the rubber roller, thereby aligning the sheet position in the sheet conveyance direction. I do.

JP 2013-82556 A

  However, in the configuration described in the above document, the movement of the sheet when the rubber roller rotates due to factors such as friction between the upper surface of the sheet bundle and the upper restricting portion is hindered, and the sheet position may not be sufficiently aligned. It was. On the other hand, if the ability of the rubber roller to move the sheet uniformly is increased by increasing the contact pressure between the rubber roller and the sheet bundle, a problem such as the buckling of the sheet between the rubber roller and the alignment reference wall may occur. is there.

  SUMMARY An advantage of some aspects of the invention is that it provides a sheet aligning apparatus capable of improving sheet bundle alignment, and a sheet processing apparatus and an image forming apparatus including the sheet aligning apparatus.

  A sheet aligning device according to an aspect of the present invention includes a sheet conveying unit that conveys a sheet in a sheet conveying direction, a sheet stacking unit on which a sheet discharged from the sheet conveying unit is stacked, and the sheet in the sheet conveying direction. A sheet holding means for holding a sheet together with the sheet stacking unit, the sheet stacking unit having a lower surface capable of supporting sheets downstream of the stacking unit and an upper surface facing the upper surface of the sheet supported by the lower surface; A contactable abutting portion capable of abutting on an upstream end of the sheets stacked on the sheet in the sheet conveying direction; and abutting on the upper surface of the sheets stacked on the sheet stacking portion and rotating to contact the sheets An alignment rotator capable of aligning the sheet position in the sheet conveying direction by moving it toward the part, a driving means for rotationally driving the alignment rotator, and the driving means Control means for controlling, when the sheet is discharged from the sheet conveying means to the sheet stacking section in a state where the first number of sheets are stacked on the sheet stacking section, the driving means A first aligning process for aligning the sheet position by rotating the aligning rotating body with a first rotation amount to the sheet stacking unit, and a second number of sheets larger than the first number of sheets in the sheet stacking unit. When the sheet is discharged from the sheet conveying unit to the sheet stacking unit in a state where the sheet is stacked, the driving unit rotates the alignment rotating body with a second rotation amount larger than the first rotation amount. The second alignment process for aligning the sheet position is executed.

  According to the sheet aligning apparatus according to the present invention, the alignment of the sheet bundle can be improved.

1 is a schematic diagram illustrating a configuration of an image forming apparatus. The perspective view of a sheet alignment apparatus. FIG. 3 is a plan view of a sheet aligning device in a first stage of a width direction alignment operation. The top view of the sheet aligning apparatus in the 2nd step of width direction alignment operation | movement. (A), (b) is a perspective view which shows the drive structure of a conveyance direction alignment roller both. Schematic which shows the 1st step (b) and the 2nd step (c) before the start of conveyance direction alignment operation | movement. FIG. 4A is a block diagram illustrating a control configuration of a sheet aligning apparatus. (B), (c) is a timing chart which shows the example of control of the 2nd alignment motor in conveyance direction alignment operation | movement. The flowchart for controlling conveyance direction alignment operation | movement. Sectional drawing which shows the shape of the width direction alignment member seen from the downstream of the sheet conveyance direction. The side view which shows the shape of the width direction alignment member seen from the width direction.

  Hereinafter, an image forming apparatus according to the present disclosure will be described with reference to the drawings. The image forming apparatus includes a printer, a copier, a facsimile machine, and a multifunction machine having these functions. As shown in FIG. 1, the image forming apparatus 1 includes an apparatus main body 100 including an electrophotographic image forming unit 102, and a sheet processing apparatus 200 that performs processing such as stapling on the image-formed sheet S. It is a multifunction machine equipped. However, FIG. 1 is a schematic diagram illustrating a configuration of the image forming apparatus 1.

  The sheet processing apparatus 200 is detachably mounted on the upper part of the apparatus main body 100, and an image reading apparatus 300 that reads image data from a document is provided on the upper part of the sheet processing apparatus 200. In the following description, “front side” and “back side” correspond to the front side and the back side in the viewpoint of FIG. 1.

  As shown in FIG. 1, the apparatus main body 100 includes a direct transfer type image forming unit 102 that directly transfers a toner image formed on a photosensitive drum 111 as a photosensitive member to a sheet S. The sheet S refers to a recording medium including special paper such as coated paper, a recording material having a special shape such as an envelope or index paper, and a plastic film or cloth for an overhead projector in addition to plain paper. Shall.

  When the image forming unit 102 is requested to start an image forming operation, the photosensitive drum 111 of the image forming unit 102 is rotationally driven. The surface of the photosensitive drum 111 is uniformly charged by the charging device 112 and then exposed by the exposure device 113. The exposure device 113 modulates and outputs a laser beam based on the image data read by the image reading device 300 or the image data input from a host computer connected via a network, and is statically applied to the surface of the photosensitive drum 111. An electrostatic latent image is formed. Then, the electrostatic latent image is visualized (developed) by the toner supplied from the developing device 114 to form a toner image.

  In parallel with such an image forming operation, the sheet feeding unit 101 performs a feeding operation for feeding the sheet S toward the image forming unit 102. The sheet feeding unit 101 includes a sheet supporting device 105 such as a cassette that supports the sheet S, and a feeding roller 106 as a feeding unit that feeds the sheet S supported by the sheet supporting device 105. The sheets S fed from the sheet support device 105 by the feeding roller 106 are conveyed to the registration unit 109 in a state where they are separated one by one by a separation mechanism such as a retard separation method or a separation pad method.

  The registration unit 109 corrects the skew of the sheet S and conveys the sheet S toward the transfer device 115 as the image forming operation in the image forming unit 102 progresses. The transfer device 115 constituted by a transfer roller transfers a toner image carried on the photosensitive drum 111 to the sheet S by electrostatic bias at a transfer nip portion formed between the transfer roller and the photosensitive drum 111. . The sheet S to which the unfixed toner image is transferred is transferred to the fixing device 103, and is sandwiched between the fixing roller 116 and the pressure roller 117, and is heated and pressed. As a result, the sheet S on which the toner is melted and fixed to form a fixed image is delivered to the discharge unit 104.

  The discharge unit 104 is a flap-shaped switching member 120 that can switch the transport direction of the sheet S between a pair of transport rollers 121 that can rotate forward and reverse, and a path toward the main body discharge unit 123 and a path toward the sheet processing apparatus 200. It has. When the processing by the sheet processing apparatus 200 is not necessary, the sheet S is guided toward the discharge roller pair 122 by the switching member 120. The discharge roller pair 122 discharges the sheet S to a main body discharge unit 123 provided on the upper portion of the apparatus main body 100 in a face-down state, that is, a state where the surface on which the toner image is formed faces downward. A sheet amount sensor 124 serving as a full load detection unit capable of detecting the amount of sheets S stacked on the main body discharge unit 123 is disposed above the main body discharge unit 123. The apparatus main body 100 is configured to interrupt the image forming operation when the sheet stacking amount exceeds a certain value based on a detection signal from the sheet amount sensor 124.

  On the other hand, when it is set to perform a process such as stapling on the sheet S on which an image is formed, the sheet S is guided toward the sheet processing apparatus 200 described later by the switching member 120. The switching member 120 guides the sheet S toward the sheet processing apparatus 200 even when the sheet S is not processed but is set to be discharged to the discharge tray 209 of the sheet processing apparatus 200.

  Further, when performing duplex printing in which images are formed on both sides of the sheet S, the sheet S is switched back by the reverse rotation of the conveyance roller pair 121, and the sheet S is transferred to the registration unit 109 via the reverse conveyance unit 125. It is conveyed. Then, the sheet S on which the image is formed on the back surface by the image forming unit 102 is conveyed to the main body discharge unit 123 or the sheet processing apparatus 200 via a path appropriately selected by the switching member 120.

  The image forming unit 102 is an example of an image forming unit that forms an image on the sheet S. The image forming unit 102 may have another configuration such as a color image forming unit of a tandem type intermediate transfer system, and may be an image other than an electrophotographic system. It may be a forming engine (for example, an ink jet method).

[Sheet Processing Device]
Next, the sheet processing apparatus 200 will be described. Note that the sheet processing in the present disclosure includes binding processing such as stapling, alignment processing for each sheet or every predetermined number of sheets, punching, and folding processing.

  As shown in FIG. 1, the sheet processing apparatus 200 includes a first transport roller pair 201, a second transport roller pair 202, an intermediate tray 203, a transport direction alignment unit 205, a width direction alignment member 240, and a discharge roller. A pair 204 and a discharge tray 209 are provided. As shown in FIG. 2, the sheet processing apparatus 200 includes a stapler 208 capable of performing stapling as an example of a processing mechanism that processes a sheet supported by the intermediate tray 203. The intermediate tray 203, the conveyance direction aligning unit 205, and the width direction aligning members 230 and 240 constitute a sheet aligning device 210 that aligns the sheets S.

  The first conveying roller pair 201 receives the sheet S discharged upward from the apparatus main body 100 and transfers it to the second conveying roller pair 202. A second conveying roller pair 202 that is an example of a sheet conveying unit discharges the sheet S to the intermediate tray 203. The sheet aligning device 210 aligns the sheet position by the transport direction aligning unit 205 and the width direction aligning members 230 and 240 in a state where the sheet S is held by the intermediate tray 203 and the width direction aligning members 230 and 240. However, the target position (alignment target position) of the alignment process performed by the sheet alignment apparatus 210 is set according to the processing content. For example, when stapling is performed, the target position is set according to the binding position of the stapler 208.

  As shown in FIGS. 2 and 3, the conveyance direction aligning unit 205 is disposed above the intermediate tray 203 and performs a conveyance direction alignment operation for aligning the sheet position with respect to the sheet conveyance direction Cv by the second conveyance roller pair 202. Is possible. The conveyance direction aligning unit 205 includes an alignment roller 206 that is rotatable about an axis extending in the direction orthogonal to the conveyance direction Cv, that is, the width direction W of the sheet S. The alignment roller 206 is movable between a contact position that contacts the upper surface of the sheet S supported by the intermediate tray 203 and a separation position that is spaced upward from the sheet S.

  The intermediate tray 203 that temporarily supports the sheet bundle to be processed by the sheet processing apparatus 200 has a support surface 213 that supports the upstream portion of the sheet S in the transport direction as a sheet stacking unit on which the sheet S is stacked. Further, the intermediate tray 203 is erected upward from the upstream end of the support surface 213 as a contact portion that can contact the rear end E2 of the sheet S supported by the support surface 213, that is, the upstream end in the sheet conveyance direction. A first reference wall 212 is provided. On both sides of the intermediate tray 203 in the width direction, support plates 211 and 211 are erected to rotatably support the roller shafts of the second transport roller pair 202 and the discharge roller pair 204. Further, a projection having a second reference wall 221 is provided on the front side of the intermediate tray 203 (see FIG. 3).

  The width direction alignment members 230 and 240 are disposed on the front side of the sheet processing apparatus 200, that is, on the one side in the width direction, and on the back side of the apparatus, that is, on the other side in the width direction. It is a pair of alignment members composed of the second alignment member 240. Each alignment member 230, 240 has a C-shaped (U-shaped) cross section that is open toward the center in the width direction when viewed from the transport direction. In other words, the alignment members 230 and 240 include the side walls 231 and 241 that face the side edges of the sheet S, that is, the end portions of the sheet S in the width direction. Support lower surfaces 232 and 242 and support upper surfaces 233 and 243 extend from the upper and lower ends of the side walls 231 and 241 toward the center in the width direction. Further, a third reference wall 234 (see FIG. 4) is provided on the side wall 231 of the first alignment member 230 so as to protrude from the wall surface toward the center in the width direction.

  The first alignment member 230 abuts against one side edge of the sheet S at the third reference wall 234, and the second alignment member 240 abuts against the other side edge of the sheet S at the side wall 241. That is, the third reference wall 234 and the side wall 241 correspond to contact surfaces that can contact the sheet S. However, the side wall 231 of the first alignment member 230 may be in contact with the side edge of the sheet S, and a protrusion serving as a contact surface may be provided on the side wall 241 of the second alignment member 240. The support lower surfaces 232 and 242 correspond to lower surface portions capable of supporting the sheet, and face the lower surface of the sheet S in contact with the contact surface. The support upper surfaces 233 and 243 correspond to the upper surface portion that opposes the upper surface of the sheet supported by the lower surface portion, and oppose the upper surface of the sheet S that is in contact with the contact surface.

  The width direction alignment members 230 and 240 are relatively movable in the width direction by an actuator including a motor (a first alignment motor described later) as a drive source and a drive transmission belt. Specifically, the alignment members 230 and 240 move between a retracted position (the position in FIG. 3) retracted to the outside of the discharge tray 209 in the width direction and an alignment position corresponding to the alignment target position of the sheet S. Is possible. However, the alignment position corresponds to the sheet width of the sheet S, and the contact surfaces (234, 241) of the alignment members 230 and 240 contact the side edges of the sheet S when the sheet S is at the alignment target position. The position set as follows.

  The discharge roller pair 204 is an example of a discharge unit that discharges the sheets aligned by the sheet aligning device 210, and is disposed between the intermediate tray 203 and the width direction alignment members 230 and 240 in the conveyance direction. A discharge tray 209, which is an example of a sheet support unit that supports a sheet discharged by the discharge unit, is disposed below the width direction alignment members 230 and 240. The discharge roller pair 204 is a so-called comb tooth in which a plurality of upper rollers 214 and a plurality of lower rollers 215 are alternately arranged in the width direction so that the outer periphery of the rollers partially overlaps when viewed from the width direction. A pair of rollers (see FIG. 2). The upper roller 214 and the lower roller 215 are relatively movable in the vertical direction, and can be switched between a closed state in which the sheet S can be nipped and conveyed and an open state in which the upper roller 214 and the lower roller 215 are separated from each other. It is.

[Sheet alignment processing]
The alignment process performed by the sheet alignment apparatus 210 will be described with reference to FIGS. 3 and 4 are plan views of the main part of the sheet processing apparatus 200 as viewed from above. For convenience of explanation, illustration of the support upper surfaces 233 and 243 of the width direction alignment members 230 and 240 is omitted. 3 and 4 show a case where the legal size sheet S is carried into the sheet aligning device 210. FIG.

  When the alignment processing by the sheet aligning device 210 is requested, the width direction aligning members 230 and 240 reach a position (standby position) where the lower surface of the sheet S can be supported by the support lower surfaces 232 and 242 as shown in FIG. Move in advance to the center in the width direction. At this time, the first alignment member 230 moves from the retracted position to a position where the position of the third reference wall 234 is aligned with the second reference wall 221 in the width direction. In addition, the second alignment member 240 moves to a position where the interval in the width direction of the support lower surfaces 232 and 242 is larger than the length in the width direction of the sheet S. In addition, the sheet aligning device 210 waits for the sheet S to be carried in a state where the alignment roller 206 of the conveyance direction aligning unit 205 is held at the separation position and the discharge roller pair 204 is held in the open state.

  When the sheet S is carried in by the second conveying roller pair 202, the sheet S is supported by the intermediate tray 203 and the width direction alignment members 230 and 240. That is, the sheet S is supported on the support surface 213 of the intermediate tray 203 on the upstream side in the transport direction, and both sides in the width direction are supported on the support lower surfaces 232 and 242 of the width direction alignment members 230 and 240 on the downstream side in the transport direction. Is done.

  Then, with the first alignment member 230 fixed, the second alignment member 240 moves toward the first alignment member 240 in the width direction. As a result, as shown in FIG. 4, the contact surfaces (234, 241) of the width direction alignment members 230, 240 are in contact with the side edges E3, E4 on both sides of the sheet S, and the width direction alignment operation is completed. To do. After the width direction alignment operation, the conveyance direction alignment operation by the conveyance direction alignment unit 205 is executed, and the sheet position in the sheet conveyance direction Cv is aligned. However, details of the conveying direction alignment operation will be described later. When the trailing edge E2 of the sheet S comes into contact with the first reference wall 212 of the intermediate tray 203, the alignment process for one sheet S is completed.

  When the sheet aligning device 210 aligns a plurality of sheets S, the above alignment process is repeated. That is, when the alignment process for the preceding sheet is completed, the sheet aligning device 210 moves the second alignment member 240 to the standby position (see FIG. 3) and waits for the subsequent sheet to be carried. A holding member that can hold the sheet S together with the support surface 213 of the intermediate tray 203 is disposed in the vicinity of the second reference wall 221, and the sheet S is aligned when the second alignment member 240 moves. Is configured to hold. When the succeeding sheet is carried in by the second transport roller pair 202, the width direction position of the succeeding sheet is aligned by the width direction aligning members 230 and 240, and then the transport direction position of the succeeding sheet is aligned by the aligning roller 206.

  Such alignment processing is repeatedly executed for a predetermined number of sheets S, that is, a number of sheets S designated as a processing unit by the sheet processing apparatus 200. When a predetermined number of sheets S are aligned, the sheet processing apparatus 200 executes a binding process by the stapler 208 as necessary. Thereafter, the discharge roller pair 204 is switched to the closed state, and the discharge roller pair 204 rotates with the width direction alignment member 230 moved to the retracted position, whereby the processed sheet bundle is stacked on the discharge tray 209. Is done.

  Note that when the sheet processing apparatus 200 is set to be discharged to the discharge tray 209 of the sheet processing apparatus 200 without performing processing such as stapling, the sheet processing apparatus 200 closes the discharge roller pair 204 and the width direction alignment member 230. , 240 are held in the retracted position. In this state, when the sheet S is fed by the second conveyance roller pair 202, the sheet S is discharged to the discharge tray 209 by the discharge roller pair 204 without being temporarily held by the intermediate tray 203.

  The sheet aligning device 210 according to the present embodiment is exposed to the outside of the housing 207 of the sheet processing apparatus 200 and is positioned by the width direction aligning members 230 and 240 (see FIGS. 1 and 2) located above the discharge tray 209. It is configured to hold both sides of the sheet S. Then, the processed sheet bundle is discharged to a discharge tray 209 below the width direction alignment members 230 and 240 with the width direction alignment members 230 and 240 being separated in the width direction. Therefore, the upper space of the discharge tray 209 can be used as a space for performing processing such as sheet alignment processing and binding processing. For example, the sheets are aligned in a state where the sheets are accommodated in the housing. The apparatus can be downsized as compared with the configuration.

  In the alignment process described above, the sheets S are aligned so as to approach the front side (FIG. 4) of the sheet processing apparatus 200. For this reason, after the alignment process, the sheet bundle discharged to the discharge tray 209 by the discharge roller pair 204 is stacked in the front side area in the discharge tray 209, and the user can access the sheet bundle. To improve usability. As shown in FIGS. 3 and 4, the length of the first alignment member 230 in the transport direction is set smaller than that of the second alignment member 240. With this configuration, the user's hand can be prevented from interfering with the first alignment member 230 located on the front side of the sheet processing apparatus 200, and usability can be improved.

[Conveying direction alignment unit]
Next, the configuration and operation of the transport direction alignment unit 205 will be described with reference to FIGS. FIGS. 5A and 5B are perspective views showing the drive configuration of the transport direction aligning unit 205, and FIGS. 6A to 6C are diagrams for explaining the transport direction aligning operation by the transport direction aligning unit 205. It is a schematic diagram of FIG. 5 and shows a state viewed from the direction of the arrows in FIGS. FIG. 7A is a block diagram showing a control configuration of the sheet aligning apparatus 210, and FIGS. 7B and 7C are views of a second aligning motor M2 corresponding to a driving unit that rotationally drives the conveyance direction aligning unit 205. FIG. It is a timing chart which shows the example of control. FIG. 8 is a flowchart showing the execution process of the conveyance direction alignment operation.

  As shown in FIGS. 5A and 5B, the transport direction alignment unit 205 includes an alignment roller 206, an alignment roller holder 270, a drive shaft 252, a gear train 250, and a cam 262. . The aligning roller 206 is a friction member having an outer peripheral portion made of rubber or the like, and can move the sheets stacked on the intermediate tray 203 to the upstream side in the sheet conveying direction by a frictional force. In other words, the aligning roller 206 rotates on the upper surface of the sheets stacked on the sheet stacking unit, and rotates the sheet toward the contact unit to align the sheet position in the sheet conveying direction. It is an example.

  The alignment roller 206 is rotatably held by an alignment roller holder 270 as a holding member, and the alignment roller holder 270 can be rotated in the vertical direction about the axis of the drive shaft 252. As a result, the alignment roller 206 can move between a contact position (downward position) where the sheets are stacked on the intermediate tray 203 and a separation position (upward position) where the alignment rollers 206 are separated from the sheet bundle stacked on the intermediate tray 203. It is.

  The drive shaft 252 is a shaft member extending along the width direction of the seat, and an input gear 251 is attached to one end portion and an output gear 253 is attached to the other end portion. The output gear 253 and the alignment roller 206 are drivingly connected via a gear train 250. The gear train 250 includes a first gear 254, a second gear 255, and a third gear 256 that are all supported by the alignment roller holder 270, and transmits the rotation of the drive shaft 252 to the alignment roller 206. Instead of the gear train, the alignment roller 206 may be driven using a drive transmission mechanism such as a belt.

  The cam 262 is a cam member attached to the drive shaft 252 and capable of pressing the locking plate 271 provided on the alignment roller holder 270 as the drive shaft 252 rotates. The cam 262 is an example of an elevating mechanism that can raise and lower the alignment rotating body between a contact position and a separation position. The alignment roller holder 270 is urged by an urging means such as a spring in a direction in which the locking plate 271 contacts the cam 262, that is, in a direction in which the alignment roller 206 is separated from the sheet. A detection flag 261 that is detected by a rotation detection sensor 312 described later is attached to the drive shaft 252.

  Hereinafter, a conveyance direction alignment operation (hereinafter simply referred to as an alignment operation) by the conveyance direction alignment unit 205 will be described. As shown in FIG. 6A, in a state before the alignment operation is started, the alignment roller 206 is held at the separation position which is the initial position. At this time, the cam 262 presses the L-shaped locking plate 271 at the arc-shaped outer peripheral portion 262a, and holds the alignment roller holder 270 at the upper position.

  When a driving force from a driving source (second alignment motor M2 to be described later) is input to the driving shaft 252 via the input gear 251, and the driving shaft 252 starts to rotate in the direction of the arrow R1, the conveying direction alignment unit 205 performs the alignment operation. To start. As shown in FIG. 6B, when the locking plate 271 is separated from the outer peripheral portion 262a of the cam 262 by the rotation of the drive shaft 252, the alignment roller holder 270 is moved downward by entering the notch portion 262b of the cam 262. And turn. Then, when the alignment roller 206 is moved to the contact position, the sheet S is driven to rotate in the direction of the arrow R2 via the gear train 250, whereby the sheet S moves upstream in the sheet conveying direction Cv. As a result, the sheet S is aligned with the sheet position where the rear end E <b> 2 contacts the first reference wall 212.

  As shown in FIG. 6C, when the drive shaft 252 further rotates, the locking plate 271 is pressed by the outer peripheral portion 262a of the cam 262, and the alignment roller holder 270 moves upward against the urging force of the urging means. Moving. As a result, the alignment roller 206 moves from the contact position to the separation position, and the alignment roller 206 is separated from the upper surface of the sheet S. Then, when the drive input to the drive shaft 252 is stopped at the timing when the drive shaft 252 rotates once, the transport direction aligning unit 205 returns to the initial state shown in FIG. In such an alignment operation, each time one sheet S is discharged to the intermediate tray 203, the width direction alignment operation by the width direction alignment members 230 and 240 is performed, and then the subsequent sheet is discharged to the intermediate tray 203. Complete before

  As shown in FIG. 7A, the image forming apparatus is provided with a control unit 301 as a control unit that controls the operation of each unit of the image forming apparatus including the sheet aligning device 210. The control unit 301 includes a CPU (central processing unit) 302, a ROM (read only memory) 303, a RAM (rewritable memory) 304, and the like. A CPU 302 as an execution unit controls an actuator provided in each unit of the image forming apparatus by reading and executing a program and setting information stored in a ROM 303 and a RAM 304 as a storage unit. For example, the control unit 301 drives the first alignment motor M1 that drives the width direction alignment members 230 and 240 and the second alignment motor M2 that drives the conveyance direction alignment unit 205 in order to control the operation of the sheet alignment apparatus 210. Control.

  The control unit 301 is connected to an operation display unit 311 that is a user interface of the image forming apparatus. The operation display unit 311 includes display means such as a liquid crystal panel and operation means such as a physical button and a touch panel function, and the type of sheet used for image formation, the presence or absence of binding processing, and a sheet processed as one sheet bundle. Information such as the number of pages (number of pages) can be input. In addition, the control unit 301 receives a detection signal from a rotation detection sensor 312 as a detection unit that can detect the rotation amount of the drive shaft 252 of the conveyance direction alignment unit 205. The rotation detection sensor 312 is a photo-interrupter that can detect the detection flag 261 (see FIG. 5A), which is a detected portion. By detecting the detection flag 261, the control unit 301 has one drive shaft 252. A signal indicating rotation can be transmitted. Note that other detection means such as a magnetic sensor may be used in place of the photo interrupter, and the rotation amount of the drive shaft 252 may be controlled by using a stepping motor or the like as a drive source.

  As shown in FIGS. 7B and 7C, in this embodiment, the second alignment motor M2 can drive the conveyance direction alignment unit 205 in either the intermittent drive mode or the continuous drive mode. As shown in FIG. 7B, in the intermittent drive mode, after the second alignment motor M2 starts to be driven, the drive is temporarily stopped when the alignment roller 206 reaches the contact position. Thereafter, the driving of the second alignment motor M2 is resumed, and the driving of the second alignment motor M2 is stopped at the timing when the drive shaft 252 rotates once and the transport direction alignment unit 205 returns to the initial state. On the other hand, as shown in FIG. 7C, in the continuous drive mode, the alignment roller moves from the separated position to the contact position and then returns to the separated position, that is, until the drive shaft 252 rotates once. The rotation of the second alignment motor M2 is continued.

[Control of conveyance direction alignment operation]
Next, an execution process for controlling the alignment operation by the conveyance direction alignment unit 205 will be described with reference to the flowchart of FIG. The following execution process is executed by the CPU 302 of the control unit 301 every time a sheet is delivered to the sheet processing apparatus 200 when a print job in which processing by the sheet processing apparatus 200 is set is input. .

  When the execution of the print job is started, one of the values designated in advance is selected, and a threshold value for changing the alignment operation by the transport direction alignment unit 205 is determined (S1). As shown in Table 1, the specified number of sheets is set to a different value depending on the type of sheet, that is, depending on the basis weight of the sheet and the presence or absence of surface treatment.

  Next, the current sheet number n (n ≧ 1) stacked on the intermediate tray 203 is acquired (S2), and compared with the value of the selected designated sheet number Nt (S3). When n <Nt, that is, when the current sheet is discharged to the intermediate tray 203 with the number of sheet bundles smaller than the threshold being stacked on the intermediate tray 203 (S3: No), the control of the second alignment motor M2 The mode is set to the intermittent drive mode (S4). Then, the conveying direction aligning unit 205 performs one alignment operation on the sheet bundle on which the current sheet is stacked (S5).

  On the other hand, when n ≧ Nt, that is, when the current sheet is discharged to the intermediate tray 203 in a state where the sheet bundle of the threshold number or more is stacked on the intermediate tray 203 (S3: Yes), the second alignment motor M2 The control mode is set to the continuous drive mode (S6). If the current sheet is not the final sheet of the print job (S7: No), the conveyance direction alignment unit 205 executes the alignment operation three times for the sheet bundle on which the current sheet is stacked (S8). ). If the current sheet is the final sheet of the print job (S7: Yes), the conveyance direction alignment unit 205 executes the alignment operation five times for the sheet bundle on which the final sheet is stacked (S9). .

  The width direction alignment operation by the width direction alignment members 230 and 240 is performed in parallel with the alignment operation of the transport direction alignment unit 205. That is, when the current sheet is discharged to the intermediate tray 203 in a state where the width direction alignment members 230 and 240 are held at the standby position (see FIG. 3), one alignment member 240 moves toward the other alignment member 230. By moving, the sheet position in the width direction is aligned (see FIG. 4). Further, the width direction alignment member 240 moves to the standby position after the transport direction alignment operation (S5, S8, S9) is performed and before the next sheet is discharged to the intermediate tray 203. When the alignment operation in the width direction and the conveyance direction with respect to the final sheet of the print job is completed, the binding process by the stapler 208 is executed as necessary. Thereafter, the sheet bundle is discharged to the discharge tray 209 by driving the pair of discharge rollers 204 while the width direction alignment members 230 and 240 are moved to the retracted position.

[Effect of this embodiment]
As described above, the alignment operation by the conveyance direction alignment unit 205 is a state in which a part of the sheet bundle stacked on the intermediate tray 203 is held by the width direction alignment members 230 and 240 as sheet holding means (see FIG. 4). Is executed. The width direction alignment members 230 and 240 support the lower surface of the sheet bundle by support lower surfaces 232 and 242 that are lower surface portions, and hold the upper surface of the sheet bundle by support upper surfaces 233 and 243 that are upper surface portions. Accordingly, as the number of sheet bundles stacked on the intermediate tray 203 increases, the uppermost sheet is more likely to come into contact with the support upper surfaces 233 and 243, and the conveyance resistance when the alignment roller 206 moves the uppermost sheet is increased. There is a tendency to grow. Further, when the sheet is curled, such a tendency is intensified because the uppermost sheet can contact the support upper surfaces 233 and 243 even when the number of sheet bundles is relatively small.

  In this embodiment, the number of alignment operations performed by the conveyance direction alignment unit 205 is changed according to the number of sheet bundles stacked on the intermediate tray 203. That is, when the current sheet is discharged to the intermediate tray 203 in a state where the first number of sheet bundles are stacked on the intermediate tray, one alignment operation is performed as the first alignment process (FIG. 8). S5). On the other hand, when the current sheet is discharged to the intermediate tray 203 in a state where the second number of sheet bundles larger than the first number are stacked, a plurality of alignment operations are performed as the second alignment processing ( S8, S9).

  For this reason, when the conveyance resistance is assumed to be relatively large, the aligning roller 206 performs the aligning operation a plurality of times, thereby increasing the ability of the aligning roller 206 to move the sheet and improving the alignment of the sheet bundle. Can be improved. Further, when the conveyance resistance is relatively small, the alignment roller 206 is configured to align the sheet position by a minimum alignment operation. For this reason, the operation sound accompanying the alignment operation is suppressed and the productivity of the sheet processing apparatus 200 is improved, and the sheet is buckled between the alignment roller 206 and the first reference wall 212 or the sheet is rubbed by the alignment roller 206. Damage can be reduced.

  In particular, when forming a predetermined number of sheets, that is, a number of sheets designated by a print job, when aligning the last sheet of a predetermined number (S9), the number of alignment operations is aligned with the previous sheets. Many are set as compared with (S8). For this reason, the alignment property of the sheet bundle can be further improved by increasing the ability of the alignment roller 206 to move the sheet with respect to the last sheet that is supposed to have the largest conveyance resistance.

  In addition, the number of alignment operations (the number of rotations of the drive shaft 252) is changed in a configuration in which the alignment roller 206 moves between the contact position and the separation position in conjunction with the rotation driving of the alignment roller 206. Thus, the rotation amount of the alignment roller 206 is changed. Therefore, the sheet bundle can be improved in alignment while reducing the cost as compared with the case where the driving means for bringing the alignment roller 206 into and out of contact with the sheet bundle is provided separately from the second alignment motor M2. Can be planned.

  Further, as illustrated in Table 1, the threshold value for changing the number of alignment operations is set to a different value depending on the type of sheet. In other words, for thick sheets, sheets with high surface smoothness, and sheets that tend to curl during image formation, such as a sheet that tends to have high transport resistance, the alignment operation can be performed multiple times even with a relatively small number of sheets. doing. By performing control according to the sheet characteristics, it is possible to improve sheet bundle alignment without unnecessarily increasing the number of alignment operations.

  Here, as shown in FIG. 6B, when the number of sheet bundles stacked on the intermediate tray 203 is small, the alignment roller 206 directly receives the reaction force from the support surface 213 of the intermediate tray 203, and The amount of deformation of the rubber layer on the outer peripheral portion is greater than when the number of sheet bundles is large. Therefore, in this embodiment, in the first alignment process, the second alignment motor M2 is driven in the intermittent drive mode (S4 in FIG. 8). As a result, the alignment roller 206 contacts the sheet bundle in a state where the rotation is stopped, and then starts to move the sheet as the second alignment motor M2 resumes driving. In other words, in a situation where the number of sheet bundles is small and the alignment roller 206 easily hits the support surface 213 and jumps, the alignment roller 206 is rotated to rotate the alignment roller 206 after the contact state between the alignment roller 206 and the sheet bundle is stabilized. Can increase the sex. On the other hand, in the second alignment process, since the alignment roller 206 is buffered by the buffering property of the sheet bundle itself, productivity can be improved by continuously driving the second alignment motor M2.

[Modification]
In the flowchart shown in FIG. 8, the configuration in which the alignment operation in the transport direction is controlled in three steps of once, three times, and five times is shown, but it may be two steps or may be changed to four or more steps. Note that the configuration in which the alignment operation is changed in two stages includes a case where the number of alignment operations is increased only for the final sheet of the number of sheets specified in the print job.

  In addition, a configuration in which driving means (for example, a solenoid capable of swinging the alignment roller holder 270) for bringing the alignment roller 206 into and out of contact with the sheet bundle may be used. In this case, the rotation amount of the aligning roller 206 in a state where the aligning roller 206 can align the sheets, that is, in a state where the aligning roller 206 is in contact with the sheet bundle, may be changed according to the number of sheet bundles stacked on the intermediate tray 203. In short, according to the number of sheet bundles held by the sheet stacking unit and the sheet holding means, the first alignment processing for rotating the alignment rotating body by the first rotation amount and the second alignment amount larger than the first rotation amount. Any configuration that executes the second alignment process of rotating the alignment rotating body by the amount of rotation may be used.

  The alignment roller 206 is an example of an alignment rotator, and may be configured to perform alignment operation in the sheet conveyance direction by a rotation member in which roller members are arranged in a plurality of positions in the width direction or a belt member such as a knurled belt.

[Shape of alignment member]
Next, the shape and operation of the width direction alignment members 230 and 240 will be described with reference to FIGS. 9 and 10. 9 is a cross-sectional view of the width direction alignment members 230 and 240 viewed from the downstream side in the conveyance direction (the direction of the arrow X1 in FIG. 1), and FIG. 10 illustrates the width direction alignment members 240 viewed from the width direction of the sheet. It is a side view.

  As shown in FIG. 9, the support lower surfaces 232 and 242 of the width direction alignment members 230 and 240 are inclined upward toward the center in the width direction on a plane orthogonal to the transport direction. Similarly, the support upper surfaces 233 and 243 of the width direction alignment members 230 and 240 are also inclined so as to be substantially parallel to the opposing support lower surfaces 232 and 242. In other words, for each of the pair of alignment members, the support lower surfaces 232 and 242 that are the lower surface portions and the support upper surfaces 233 and 243 that are the upper surface portions are inclined upward toward the other alignment member in the width direction. .

  Hereinafter, the end portions on the outer side in the width direction of the support lower surfaces 232 and 242, that is, the end portions adjacent to the third reference wall 234 or the side wall 241 on which the support lower surfaces 232 and 242 are contact surfaces are referred to as first end portions A 1 and B 1. Ends on the inner side in the width direction of the support lower surfaces 232 and 242 are referred to as second ends A2 and B2. Further, in the support upper surfaces 233 and 243, the outer end portions in the width direction are third end portions A3 and B3, and the end portions in the width direction of the support upper surfaces 233 and 243 are fourth end portions A4 and B4. The second ends A2 and B2 are upper ends of the support lower surfaces 232 and 242 corresponding to the lower surface, and the third ends A3 and B3 are lower ends of the support upper surfaces 233 and 243 corresponding to the upper surface.

  When one sheet S is held by the width direction alignment members 230 and 240 under the inclination of the support lower surfaces 232 and 242, the lower surface of the sheet S is mainly the support lower surface as shown in FIG. It is supported by the second ends A2, B2 of 232,242. On the other hand, the side edges E3 and E4 of the sheet S are held below the height of the upper end positions of the third reference wall 234 and the side wall 241 which are the contact surfaces by the third ends A3 and B3 of the support upper surfaces 233 and 244. The Accordingly, the second end portions A2 and B2 function as a lower surface holding portion that supports the lower surface of the sheet that is in contact with the contact surface of the alignment member. The third end portions A3 and B3 are located between the lower surface holding portion and the contact surface in the width direction, and function as an upper surface holding portion that holds the upper surface of the sheet in contact with the contact surface.

  The width direction alignment members 230 and 240 according to the present embodiment are configured such that the lower surface holding portion and the upper surface holding portion are arranged in a substantially straight line on a plane perpendicular to the conveyance direction. In other words, for each of the pair of alignment members, the distance between the lower end portion (A3, B3) of the upper surface portion and the upper end portion (A2, B2) of the lower surface portion in the vertical direction is at least the vertical direction of the contact surface. It arrange | positions so that it may become smaller than length of. As shown in FIG. 9, for the first alignment member 230, the distance between the second end A <b> 2 and the third end A <b> 3 in the vertical direction is larger than the vertical length L <b> 3 of the third reference wall 234. It is set to be smaller by the height difference L1 between the second end A2 and the first end A1. Further, with respect to the second alignment member 240, the distance between the second end B2 and the third end B3 in the vertical direction is larger than the length L4 of the side wall 241 in the vertical direction. It is set smaller by the height difference L2 of the end B1.

  With such a configuration, the sheet S held by the width direction alignment members 230 and 240 is supported by the second end portions A2 and B2 on the lower surface, while the upper surface is the third end portion A3 on the outer side in the width direction. , B3. For this reason, the side ends E3 and E4 of the sheet S are restricted from being displaced upward with respect to the second ends A2 and B2, and the downward deflection of the sheet S is suppressed. Accordingly, it is possible to reduce the deformation due to the weight of the sheet S and the curl, and improve the alignment accuracy of the sheet position in the width direction. Further, the number of sheets that can be received by the width direction alignment members 230 and 240 is increased as compared with the configuration in which the deformation amount of the sheet is reduced by simply bringing the support lower surfaces 232 and 242 closer to the support upper surfaces 233 and 243. be able to. In addition, if the space | interval between the lower end part of an upper surface part and the upper end part of a lower surface part becomes smaller than the length of the up-down direction of an abutting surface, for example, while arranging the support lower surfaces 232 and 242 horizontally in the width direction, Further, a rib protruding upward may be provided on the inner side in the width direction of the support lower surfaces 232 and 242.

  As shown in FIG. 10, the support upper surface 243 includes a first upper surface portion 243a extending along the sheet conveying direction of the second conveying roller pair 202 and a second upper surface portion 243b inclined with respect to the first upper surface portion 243a. I have. The first upper surface portion 243a is located above the tangent line T1 in the nip portion N1 when viewed from the width direction, and extends in a direction substantially along the tangent line T1. The second upper surface portion 243b extends in a direction inclined from the first upper surface portion 243a toward the downstream in the sheet conveying direction so as to intersect the tangent line T1. Although the second alignment member 240 is illustrated in FIG. 10, the same applies to the first alignment member 240. That is, as shown in FIG. 2, the support upper surface 233 of the first alignment member 230 is inclined so as to intersect the tangent line T1 with the first upper surface part 233a located above the tangent line T1 when viewed from the width direction. A second upper surface portion 233b.

  With such a configuration, the front end E1 of the sheet S sent in the direction along the tangent line T1 from the pair of conveying rollers 202 has a support upper surface in the vicinity of the intersection P0 between the tangent line T1 and the support upper surfaces 233 and 243 viewed from the width direction. 233 and 243 (see FIG. 10). Then, by receiving a downward reaction force from the support upper surfaces 233 and 243, the sheet S is conveyed in a curved state so as to have an angle close to the horizontal direction on the downstream side of the intersection P0. By such a curvature, the second moment of section of the sheet S in a plane perpendicular to the width direction is increased, so that the downward deflection of the sheet S can be more effectively suppressed.

  Furthermore, as shown in FIG. 10, a shape (242b) inclined upward toward the downstream side in the sheet conveying direction is provided at the most downstream portion of the support lower surface 242. In other words, the support lower surface 242 includes a first lower surface portion 242a that faces the support upper surface 243, and a second lower surface portion 242b that protrudes downstream from the support upper surface 243 in the sheet conveying direction. The second lower surface portion 242b extends in a direction inclined with respect to the first lower surface portion 242a so as to incline upward from the first lower surface portion 242a toward the downstream in the sheet conveying direction when viewed from the width direction. Yes. Further, as shown in FIG. 2, the support lower surface 232 of the first alignment member 230 also includes a first lower surface portion 232a facing the support upper surface 233, and a second lower surface portion 232b inclined with respect to the first lower surface portion 232a. Is provided.

  When a relatively long sheet such as a legal size is discharged from the second conveying roller pair 202, as shown in FIGS. 3 and 4, the front edge E1 of the sheet S extends from the width direction alignment members 230 and 240 in the sheet conveying direction Cv. It will be in the state which protruded downstream. In such a case, since the downstream portion of the sheet S is lifted by the second lower surface portions 232b and 242b of the support lower surfaces 232 and 242, the sagging of the front end E1 due to the weight of the sheet S is suppressed. Further, since the drooping of the front end E1 is suppressed, when the sheet bundle is discharged to the discharge tray 209 by the discharge roller pair 204, the front end of the discharged sheet bundle pushes out the sheets already stacked on the discharge tray 209. It is possible to reduce the possibility of being lost. Further, since the second lower surface portions 232b and 242b are provided, it becomes possible to reduce the extrusion of the sheet bundle without increasing the vertical distance between the width direction alignment members 230 and 240 and the discharge tray 209. This also contributes to downsizing of the equipment.

  Here, the relationship between the shape of the width direction alignment members 230 and 240 as described above and the control of the alignment operation by the conveyance direction alignment unit 205 will be described. As described above, in this embodiment, the downward deflection of the sheet bundle is restricted by inclining the lower support surfaces 232 and 242 and the upper support surfaces 233 and 243 of the width direction alignment members 230 and 240 with respect to the horizontal direction. . The support lower surfaces 232 and 242 and the support upper surfaces 233 and 243 are provided with second lower surface portions 232b and 242b and second upper surface portions 233b and 243b that can regulate the shape of the sheet viewed from the width direction.

  However, these features may act in the direction of increasing resistance when moving the uppermost sheet of the sheet bundle held by the width direction alignment members 230 and 240. For example, when the thickness of the sheet bundle increases, the sheet bundle is bent upward along the inclination of the support lower surfaces 232 and 242 and the support upper surfaces 233 and 243 when viewed from the sheet conveying direction, and the upper surface of the sheet bundle is supported. It is thought that it contacts the upper surfaces 233 and 243 (see FIG. 6). Further, since the distance between the support upper surfaces 233 and 243 and the support lower surfaces 232 and 242 becomes narrower toward the downstream side in the sheet conveying direction due to the inclination of the second upper surface portions 233b and 243b (see FIG. 10), the upper surface of the sheet bundle is It is also conceivable that the second upper surface portions 233b and 243b come into contact with each other.

  On the other hand, the conveyance direction aligning unit 205 according to the present embodiment is configured to execute the aligning operation a plurality of times when the number of sheet bundles is a certain number or more. For this reason, even when the conveyance resistance of the uppermost sheet increases due to the shape of the conveyance direction alignment members 230 and 240, the sheet position in the sheet conveyance direction is stably aligned. Therefore, according to the configuration of this embodiment, the above-described effect corresponding to the shape of the width direction alignment members 230 and 240 can be obtained, and at the same time, alignment in the sheet conveyance direction can be ensured.

[Other Embodiments]
The present invention supplies a program that realizes one or more functions of the above-described embodiments to a system or apparatus via a network or a storage medium, and one or more processors in a computer of the system or apparatus read and execute the program This process can be realized. It can also be realized by a circuit (for example, ASIC) that realizes one or more functions.

DESCRIPTION OF SYMBOLS 1 ... Image forming apparatus / 102 ... Image forming means (image forming part) / 200 ... Sheet processing apparatus / 202 ... Sheet conveying means (2nd conveyance roller pair) / 208 ... Sheet processing means (stapler) / 212 ... Contact part (First reference wall) / 213 ... sheet stacking portion (support surface of intermediate tray) / 206 ... alignment rotating body (alignment roller) / 210 ... sheet alignment device / 230,240 ... sheet holding means (width direction alignment member) / 231, 244 ... abutment surface (side wall, third reference wall) / 232, 242. Portion (support upper surface) / 233a, 243a ... first upper surface portion / 233b, 243b ... second upper surface portion / 252 ... drive shaft / 261 ... detected portion (detection flag) / 262 ... elevating mechanism, cam member (cam) / 270 ... holding member (alignment roller holder) / 301 ... control means (control part) / 312 ... detection means (rotation detection sensor) / A2, B2 ... upper end part of the lower surface part / A3, B3 ... lower end part of the upper surface part / M2 ... Driving means (second alignment motor) / S5 ... First alignment process / S8, S9 ... Second alignment process

Claims (13)

Sheet conveying means for conveying the sheet in the sheet conveying direction;
A sheet stacking unit on which sheets discharged from the sheet conveying unit are stacked;
A sheet holding unit that has a lower surface part capable of supporting a sheet downstream of the sheet stacking unit in the sheet conveying direction and an upper surface part facing an upper surface of the sheet supported by the lower surface unit, and holds the sheet together with the sheet stacking unit. Means,
A contactable contact portion capable of contacting an upstream end of the sheets stacked on the sheet stacking portion in the sheet conveying direction;
An alignment rotating body capable of aligning the sheet position in the sheet conveying direction by rotating in contact with the upper surface of the sheet stacked on the sheet stacking unit and moving the sheet toward the contact unit;
Drive means for rotationally driving the alignment rotating body;
Control means for controlling the drive means,
When the sheet is discharged from the sheet conveying unit to the sheet stacking unit in a state where the first number of sheets are stacked on the sheet stacking unit, the control unit causes the driving unit to rotate the driving unit at a first rotation amount. A first alignment process for aligning the sheet position is performed by rotationally driving the alignment rotator, and the sheet is conveyed in a state where a second number of sheets larger than the first number is stacked on the sheet stacking unit. When the sheet is discharged from the sheet to the sheet stacking unit, the driving unit rotates the alignment rotating body with a second rotation amount larger than the first rotation amount to align the sheet position. Perform alignment processing,
A sheet aligning apparatus characterized by the above. An elevating mechanism that moves the alignment rotator to a contact position that contacts the sheets stacked on the sheet stacking unit and a separation position that separates from the sheets stacked on the sheet stacking unit by a driving force from the driving unit. With
The control unit is configured to perform the driving operation in units of an alignment operation in which the alignment rotating body is rotationally driven by the lifting mechanism while being moved from the separation position to the contact position and then returned to the separation position by the lifting mechanism. In the first alignment process, the alignment rotator is caused to perform one alignment operation, and in the second alignment process, the alignment rotator is allowed to execute a plurality of alignment operations.
The sheet aligning apparatus according to claim 1, wherein A holding member that rotatably holds the alignment rotating body and is movable with respect to the sheet stacking unit;
A drive shaft for transmitting the drive force of the drive means to the alignment rotating body;
Detecting means capable of transmitting the rotation of the drive shaft to the control means by detecting a detected portion provided on the drive shaft, and
The elevating mechanism includes a cam member supported by the drive shaft and capable of pressing the holding member as the drive shaft rotates, and is aligned with the alignment rotating body once during the rotation of the drive shaft. Perform the action,
The sheet aligning apparatus according to claim 2, wherein In the alignment operation in the first alignment process, the control unit temporarily stops driving of the driving unit in a state where the alignment rotating body moves from the separated position to the contact position, and then drives the driving unit. In the alignment operation in the second alignment process, the drive unit continues to be driven until the alignment rotating body moves from the separation position to the contact position and returns to the separation position. To
The sheet aligning apparatus according to claim 2, wherein the sheet aligning apparatus is characterized in that: The control means sets a different threshold value depending on the type of sheets stacked on the sheet stacking unit, and the sheet transporting unit sets a threshold number of sheets less than the threshold in the sheet stacking unit. When the sheets are discharged to the sheet stacking unit, the first alignment process is performed, and the sheet stacking unit loads the sheet stacking unit with the number of sheets equal to or greater than the threshold to the sheet stacking unit. Executing the second alignment process when the sheet is discharged;
The sheet aligning apparatus according to claim 1, wherein the sheet aligning apparatus is a sheet aligning apparatus. When the predetermined number of sheets are discharged to the sheet stacking unit by the sheet conveying unit, the control unit is configured to align the last sheet of the predetermined number before the last sheet. Rotating the alignment rotating body by a larger amount of rotation than aligning the sheet discharged to
The sheet aligning apparatus according to claim 1, wherein the sheet aligning apparatus is characterized in that: The sheet holding means is a pair of width direction alignment members that are relatively movable in a width direction perpendicular to the sheet conveying direction of the sheets stacked on the sheet stacking unit,
Each of the pair of width direction alignment members connects the lower surface portion, the upper surface portion, the lower surface portion and the upper surface portion, and abuts against an end portion of the sheets stacked on the sheet stacking portion in the width direction. A contact surface that can contact,
The sheet aligning apparatus according to any one of claims 1 to 6, wherein the sheet aligning apparatus is characterized in that: For each of the pair of alignment members, the upper surface portion extends from the upper end of the contact surface in a direction inclined upward toward the other alignment member with respect to the width direction, and the lower surface portion is the contact surface Extending in a direction inclined upward from the lower end of the head toward the other alignment member with respect to the width direction,
The sheet aligning apparatus according to claim 7, wherein For each of the pair of alignment members, an upper end portion of the lower surface portion is located above a lower end of the contact surface in a plane perpendicular to the sheet conveying direction, and an upper end portion of the lower surface portion in the vertical direction The distance between the lower end portion of the upper surface portion is smaller than the length of the contact surface in the vertical direction,
The sheet aligning apparatus according to claim 7, wherein The sheet conveying means is a pair of conveying rollers;
The upper surface portion is
A first upper surface portion located above a tangent line passing through a nip portion of the conveying roller pair as viewed from a direction orthogonal to the sheet conveying direction;
A second upper surface portion extending from the first upper surface portion in a direction inclined so as to intersect the tangent line toward the downstream in the sheet conveying direction,
The sheet aligning apparatus according to any one of claims 1 to 9, wherein the sheet aligning apparatus is characterized in that: The lower surface portion is
A first lower surface facing the upper surface;
A second protrusion that projects downstream from the upper surface portion in the sheet conveying direction and extends upwardly from the first lower surface portion toward the downstream in the sheet conveying direction as viewed from a direction orthogonal to the sheet conveying direction. Including a lower surface portion,
The sheet aligning apparatus according to any one of claims 1 to 10, wherein the sheet aligning apparatus is characterized in that: A sheet aligning device according to any one of claims 1 to 11,
Sheet processing means for processing sheets aligned by the sheet aligning device,
A sheet processing apparatus. Image forming means for forming an image on a sheet;
The sheet aligning apparatus according to any one of claims 1 to 11, which aligns a sheet on which an image is formed by the image forming unit.
An image forming apparatus.

Images