JP2005306506A - Sheet treatment device and image formation device provided with this - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sheet treatment device and an image formation device provided with this capable of stably aligning a position in a sheet conveying direction of a sheet with a simple constitution. <P>SOLUTION: A restriction member 411 for restricting a position in the sheet conveying direction of the sheet is provided on an end in an upstream side in the sheet conveying direction of a sheet piling up means 410 for piling up the sheet to be treated. After the sheet conveyed to the sheet piling up means 410 is conveyed in the sheet conveying direction by normal rotation of a sheet conveying means 407 capable of being normally and reversely rotated, it is conveyed by reverse rotation of the sheet conveying means 407 so as to be abutted on a rear end stopper 411. Further, after the sheet is conveyed so as to be abutted on the rear end stopper 411, the sheet conveying means 407 is also reversely rotated for a predetermined time. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a sheet processing apparatus and an image forming apparatus including the same, and more particularly to a configuration for aligning the position of a sheet to be processed in the sheet conveyance direction.

  2. Description of the Related Art Conventionally, in image forming apparatuses such as copying machines, printers, facsimiles, and composite devices of these, a sheet processing apparatus that performs processing such as binding processing on sheets discharged from the image forming apparatus main body is provided on the image forming apparatus main body. There is something to be provided.

  As such a sheet processing apparatus, a sheet stacking operation for transporting a sheet discharged from the image forming apparatus main body to a sheet processing unit, and stacking and aligning the discharged sheet in the sheet processing unit, and a sheet In some cases, processing such as stapling is performed.

  By the way, in such a conventional sheet processing apparatus, when processing a sheet bundle, the sheet is discharged from the discharge passage so as to fly onto the processing tray, and the discharged sheet is moved in the direction opposite to the discharge direction. An alignment operation is performed, and then a sheet bundle is bound after aligning end portions in the sheet conveyance direction (see Patent Document 1).

  Here, in order to perform such an alignment operation, the sheet processing apparatus rotates in synchronization with an elastic member 671 called a paddle and a discharge roller 617 for discharging the sheet S onto the processing tray 672 as shown in FIG. The trailing edge of the sheet S is pulled back to the nip point between the alignment belt 619 and the processing tray 672 by an elastic member (paddle) 671, and then the sheet S is not shown by the frictional force of the alignment belt 619. By aligning with the alignment abutting member, the position in the conveying direction is regulated to perform alignment.

  Further, the sheet discharged onto the processing tray and abutted against the alignment abutting member and aligned at the end in the conveyance direction is then further moved by a width direction alignment member that is movable in the width direction orthogonal to the conveyance direction. The position in the width direction is regulated in response to an alignment operation that is sandwiched in the width direction.

JP 2002-37512 A

  By the way, in such a conventional sheet processing apparatus and an image forming apparatus including the same, several parts such as a discharge roller 617, an elastic member 671, and an alignment belt 619 are necessary to convey and align the sheet. For this reason, the number of parts including those around the parts has increased.

  Further, when the frictional force obtained by the rotation of the elastic member 671 is used to align the sheet S in the conveyance direction, the amount of deflection of the elastic member 671 increases as the number of sheets S stacked increases. When the contact pressure of the elastic member 671 with respect to the sheet S increases and the sheet S comes into contact with the abutting portion, the sheet S may be buckled. When the frictional force obtained by the rotation of the alignment belt is used as another means for performing the alignment in the conveyance direction of the sheet S, the alignment is caused by subtle blurring of the alignment belt that occurs during the rotation of the alignment belt. There is a risk of causing a deviation in the sheet bundle.

  Further, since the sheet S is discharged so as to fly onto the processing tray by the discharge roller 617, when the sheet S is discharged onto the processing tray, the dropping position may not be stable depending on the type of the sheet S. In some cases, the applied sheet cannot be stably abutted against the alignment abutting portion.

  The present invention has been made in view of such a current situation, and provides a sheet processing apparatus capable of stably aligning the position of a sheet in the sheet conveyance direction and an image forming apparatus including the same with a simple configuration. It is intended to provide.

  The present invention comprises a sheet stacking unit that stacks sheets to be processed, forms a sheet bundle by aligning the sheets conveyed to the sheet stacking unit, and performs processing on the aligned sheet bundle In the apparatus, provided on the upstream side of the sheet stacking direction of the sheet stacking unit, and restricting the position of the sheet in the sheet transport direction, and after transporting the sheet transported to the sheet stacking unit in the sheet transport direction, Sheet conveying means capable of reversing the sheet in the direction opposite to the sheet conveying direction so that the sheet is brought into contact with the regulating member, and the sheet is moved in the sheet conveying direction by forward rotation of the sheet conveying means. After the sheet is conveyed, the sheet is conveyed by reversing the sheet conveying means so that the sheet contacts the regulating member, and the sheet is conveyed to the regulating member Even after transporting to abut, it is characterized in that the said sheet conveying means so as to reverse a predetermined time.

  In the invention, it is preferable that the sheet conveying means slips on the sheet after the sheet comes into contact with the regulating member.

  In the invention, it is preferable that the sheet conveying means is constituted by a cylindrical member.

  The present invention is characterized in that the outer peripheral portion of the cylindrical member is formed of an elastic body.

  In the present invention, the sheet conveying means is moved to a position that does not interfere with the conveyance of the sheet when the sheet is conveyed to the sheet stacking means, and after the sheet is conveyed to the sheet stacking means. A position control means for moving the sheet to a position in contact with the sheet is provided.

  Further, the present invention provides a side end regulating member that is provided at an end in the width direction orthogonal to the sheet conveying direction of the sheet stacking unit, and that regulates the position of the end in the width direction of the sheet; A moving means for moving the sheet in the width direction in contact with the side edge regulating member, and each time the sheet is conveyed to the sheet stacking means by the moving means. The sheet conveying means is moved integrally with the sheet in the width direction, and the sheet is brought into contact with the side end regulating member.

  In the present invention, the sheet conveying means conveys the sheet in a direction opposite to the sheet conveying direction to contact the regulating member, and the moving means moves the sheet in the width direction integrally with the sheet conveying means. The sheet is brought into contact with the side end regulating member to align the sheet.

  According to the present invention, in the image forming apparatus, the image forming unit includes an image forming unit that forms an image on the sheet, and the sheet processing device according to any one of the above that processes the sheet on which the image is formed by the image forming unit. It is characterized by.

  According to another aspect of the present invention, there is provided an image forming apparatus in which sheets conveyed from an image forming unit to a sheet stacking unit are aligned to form a sheet bundle, and a binding process is performed on the aligned sheet bundle by a binding unit. A regulating member that is provided upstream of the stacking unit in the sheet conveying direction and regulates the position of the sheet in the sheet conveying direction; and after the sheet conveyed to the sheet stacking unit is conveyed in the sheet conveying direction, the sheet is regulated Sheet conveying means capable of rotating forward and backward to convey the sheet in a direction opposite to the sheet conveying direction so as to contact the member, and after conveying the sheet in the sheet conveying direction by forward rotation of the sheet conveying means, Reversing the sheet conveying means conveys the sheet so that the sheet comes into contact with the regulating member, and carries the sheet so as to come into contact with the regulating member. Even after, it is characterized in that the said sheet conveying means so as to reverse a predetermined time.

  According to the present invention, the sheet is conveyed by reversing the sheet conveying means so as to come into contact with the regulating member that regulates the position in the sheet conveying direction, and thereafter, the sheet conveying means is reversely rotated for a predetermined time. Can be reliably brought into contact with the regulating member. And by comprising in this way, the position of the sheet | seat conveyance direction can be adjusted stably with the simple structure which does not require many members.

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

  FIG. 1 is a cross-sectional view showing a configuration of an image forming apparatus provided with a sheet treatment apparatus according to an embodiment of the present invention, in which A is an image forming apparatus, 500 is an image forming apparatus main body, and 300 is an image. An automatic document feeder (ADF) 400 provided on the upper surface of the forming apparatus main body 500 is a sheet processing apparatus that processes sheets discharged from the image forming apparatus A.

  In the figure, reference numeral 120 denotes a reader unit (image input device) that converts a document into image data, and 200 includes a plurality of types of sheet cassettes 204 and 205, and the image data is converted into a visible image on the sheet by a print command. It is a printer unit which is an image forming unit to output.

  In the image forming apparatus A having such a configuration, when an original image is read to form an image, first, the originals stacked on the automatic original feeder (ADF) 300 are sequentially placed one by one on the platen glass. It is carried on the surface 102.

  Next, when the document is conveyed to a predetermined position on the glass surface 102 in this way, the lamp 103 of the reader unit 120 is turned on, and the scanner unit 101 moves to irradiate the document. Then, the reflected light from the original is input to the CCD image sensor unit 109 through the mirrors 105, 106, 107 and the lens 108, and electrical processing such as photoelectric conversion is performed in the CCD image sensor unit 109, and normal digital processing is performed. Is given.

  Next, the image signal subjected to the electrical processing in this manner is converted into a modulated optical signal by the exposure control unit 201 of the printer unit 200, and irradiates the photosensitive drum 202. Then, a latent image is formed on the photosensitive drum 202 by the irradiation light, and the latent image is developed by the developing device 203. As a result, a toner image is formed on the photosensitive drum 202.

  Next, the sheet S is conveyed from the sheet cassettes 204 and 205 in synchronization with the leading edge of the toner image, and the toner image is transferred to the sheet S by the transfer unit 206. Thereafter, the toner image transferred to the sheet S is fixed by the fixing unit 207. After the toner image is fixed in this way, the sheet S is discharged from the paper discharge unit 208 to the outside of the apparatus.

  Then, the sheet S output from the paper discharge unit 208 is conveyed to the sheet processing apparatus 400, and processing such as sorting and binding is performed in accordance with an operation mode designated in advance by the sheet processing apparatus 400.

  When outputting sequentially read images on both sides of one sheet S, first, the direction switching member 209 is once switched in the solid line direction in the drawing for the sheet S on which the toner image is fixed on one side by the fixing unit 207. Then, the direction switching member 217 is switched to the broken line direction, and the direction switching member 213 is switched to the broken line direction, so that the sheet is conveyed to the reverse path 212 via the path 218.

  Next, after the trailing edge of the sheet passes through the direction switching member 213, the direction switching member 213 is switched to the solid line direction, and the rotation direction of the roller 211 is reversed to guide the sheet to the path 210, and then to the transfer unit 206. The sheet is conveyed to form an image on the back surface of the sheet S.

  On the other hand, the sheet processing apparatus 400 has a stapling function that is a binding operation by a stapling unit in addition to a sorting operation for sorting sheets, and is sequentially discharged from the image forming apparatus main body 500 as shown in FIG. A processing tray 410 for processing the sheet S and a stack tray 421 for finally stacking a sheet bundle processed on the processing tray 410 are provided, and a sheet bundle corresponding to the number of documents is placed on the processing tray 410. And is discharged to the stack tray 421 for each sheet bundle.

  In the figure, reference numeral 401 denotes a sheet receiving unit that receives the sheet S discharged from the image forming apparatus main body 500. The sheet S received by the sheet receiving unit 401 is detected by the entrance sensor 403, and then the conveyance roller. 405 and an offset roller 407, and thereafter, the sheet is conveyed onto a processing tray 410 as a sheet stacking unit as shown in FIG. The sheets S stacked on the processing tray 410 in this way are detected by a sheet bundle discharge sensor 415 shown in FIG.

  Here, the offset roller 407 as a sheet conveying means constituted by a cylindrical member is an elastic body having elasticity close to rubber, such as rubber or foam, on the outer peripheral portion. It is held up and down by an offset roller arm 406 that can move up and down about a shaft 406a shown in FIG.

  When the sheet S is transported to the processing tray 410, the offset roller 407 has a pickup solenoid 433 as a position control unit turned on and moves to an upper position via the offset roller arm 406 so as not to prevent the sheet S from being transported. As a result, the sheet S is conveyed onto the processing tray 410 without being obstructed by the offset roller 407.

  The offset roller arm 406 can be moved up and down by a pickup solenoid 433 with a shaft 406a as a fulcrum. That is, the offset roller 407 moves up and down via the down lever 433a when the pickup solenoid 433 is turned on / off.

  Further, as shown in FIG. 5, the offset roller 407 is driven through belts 431a and 431b by a transport motor 431 capable of rotating forward and backward to drive the transport roller 405, and when the transport motor 431 rotates. Rotation in the conveyance direction (forward rotation) by an amount corresponding to the rotation amount of the conveyance motor 431, or rotation in the reverse direction of the conveyance direction (hereinafter referred to as reverse rotation).

  In this embodiment, when the sheet bundle discharge sensor 415 detects the conveyed sheet, the pickup solenoid 433 is turned off, so that the offset roller 407 is lowered by its own weight and is placed on the sheet. After landing (contact), the sheet rotates in the sheet conveying direction for a predetermined time and then reverses when the predetermined time elapses.

  By reversing in this way, the trailing edge of the sheet is erected at the upstream end of the processing tray 410 in the conveyance direction, and the sheet trailing edge stopper 411 as a regulating member that regulates the position of the sheet S in the sheet conveyance direction. The sheet S is aligned in the conveying direction.

  In FIG. 4, reference numeral 416 denotes a positioning wall as a side end regulating member that regulates the position of the end of the sheet in the direction orthogonal to the sheet conveyance direction (hereinafter referred to as the width direction), and 420 denotes the vicinity of the positioning wall of the processing tray 410 The offset roller 407 is a positive unit as a driving unit that constitutes a moving unit together with the offset roller 407. The stapler unit is a stapling unit that performs stapling on a sheet bundle formed on the processing tray 410. The offset motor 432 which can be rotated in reverse direction is moved in the width direction via the rack 406c and the pinion 432a, and can approach the positioning wall 416.

  When the offset roller 407 approaches the positioning wall 416 in this way, the sheet that is abutted against the sheet trailing edge stopper 411 and aligned in the conveyance direction moves to the positioning wall 416 by the frictional force of the offset roller 407. Thus, positioning in the width direction is performed. After the sheet S hits the positioning wall 416, the offset roller 407 moves and stops while sliding on the sheet.

  Here, by providing such an offset roller 407, the sheet discharged onto the processing tray 410 is conveyed to the stack tray side by the offset roller 407 that rotates in the sheet conveying direction as shown in FIG. After that, as shown in FIG. 6B, the sheet is returned to the sheet trailing edge stopper 411 by the reverse rotation of the offset roller 407, and then the trailing edge is abutted against the trailing edge stopper 411 to be aligned.

  6 and FIG. 7, FIG. 8, and FIG. 13, which will be described later, will be described using a configuration in which the offset roller 407 is arranged inside the offset roller arm 406, unlike FIG. 4 described above. However, this difference in configuration is merely a design difference, and there is no difference in function and operation from the configuration shown in FIG.

  Thereafter, as shown in FIG. 6C, the offset roller 407 is moved to the positioning wall side along the shaft 406a while being in contact with the sheet S, so that the end in the width direction of the sheet S is positioned. The sheet S is pressed against the wall 416 and the sheet S is aligned in the width direction.

  On the other hand, in FIG. 5, reference numeral 412 denotes a sheet clamp member as a sheet bundle holding unit that presses the rear end portion of the aligned sheet S from above by a biasing force by a biasing unit (not shown). When the trailing end alignment of the sheet performed after the alignment in the width direction is completed, and thereafter the offset roller 407 is lifted by the pickup solenoid 433 as shown in FIG. Thus, the aligned sheet S is pressed from above as shown in FIG.

  Thus, the sheet S previously discharged (conveyed) to the processing tray 410 can be held at a predetermined position without being influenced by the subsequent feeding by the sequentially fed sheets S. It has become.

  The sheet clamp member 412 rotates upward as shown in FIG. 8A so that the sheet S can be received when the offset roller 407 is reversely rotated, and is offset to align the ends. When the sheet S moves in the width direction together with the roller 407, the sheet S is rotated upward as shown in FIG.

  In FIG. 5, reference numeral 413 denotes a sheet bundle discharge member exemplified as a sheet bundle discharge unit for discharging the processed sheet bundle to the stack tray 421. The sheet bundle discharge member 413 allows the sheet clamp member 412 to turn freely. As shown in FIG. 9, the sheet bundle that is held and the aligned sheet bundle or the stapled sheet bundle that has been aligned and held by the sheet clamp member 412 is provided downstream of the processing tray 410. It moves in the direction of the stack tray 421.

  Further, after this, when the leading end of the processing tray 410, which is the sheet discharge position indicated by the solid line in the figure, is reached, the holding of the sheet bundle SA by the sheet clamp member 412 on the stack tray 421 is released, and the sheet bundle SA is stacked. The tray 421 is discharged and stacked.

  Here, as shown in FIG. 5, the sheet bundle discharge member 413 receives the power through the rack and pinion by the sheet bundle discharge motor 430 and discharges the sheet to the stack tray 421 and the sheet rear end. It can be reciprocated to the home position near the stopper 411. The sheet bundle discharge member 413 is normally fixed at the home position by excitation of the sheet bundle discharge motor 430.

  In FIG. 5, reference numeral 434 denotes a clamp solenoid for rotating the sheet clamp member 412. This clamp solenoid 434 is used when the offset roller 407 stops rotating after conveying the sheet and when the offset roller 407 moves in the width direction. When moving, the sheet clamp member 412 is turned on, and the sheet clamp member 412 is rotated upward via a release lever portion 412 a provided on the lever 434 a and the sheet clamp member 412.

  In this embodiment, after the sheet S is moved in the width direction, the offset roller 407 is reversely rotated again to complete the alignment operation in order to correct the deviation in the sheet conveyance direction. High-precision matching is achieved. When the specified number of sheets have been aligned, the clamp solenoid 434 closes the sheet clamp member 412 to hold the sheet bundle.

  FIG. 10 is a block diagram showing the configuration of the control unit of the sheet processing apparatus 400 having such a configuration. Reference numeral 100 denotes a CPU exemplified as the control means in the present embodiment. Here, the CPU 100 has a ROM 110 therein, and programs and the like corresponding to control procedures shown in FIGS. 11 and 12 described later are stored in the ROM 110. The CPU 100 controls each unit while reading this program.

  The CPU 100 has a built-in RAM 1210 in which work data and input data are stored, and the CPU 100 performs control by referring to data stored in the RAM 121 based on the program. Further, sensors such as an inlet sensor 403 and a sheet bundle discharge sensor 415 are connected to the input port of the CPU 100, and a conveyance motor 431, an offset motor 432, a sheet bundle discharge motor 430, and a pickup solenoid 433 are connected to the output port of the CPU 100. A motor such as a clamp solenoid 434 and a solenoid are connected. Based on the state of these sensors, the CPU 100 controls loads such as various motors and solenoids connected to the output port according to the aforementioned program.

  In addition, the CPU 100 includes a serial interface unit (I / O) 130, which transmits and receives control data to and from the image forming apparatus main body 500 (control unit thereof), and also transmits an image via the serial interface unit (I / O) 130. Each unit is controlled based on control data sent from the forming apparatus main body 500 (control unit thereof).

  Since the image forming apparatus main body 500 knows the size of the sheet discharged from the sheet discharge section 208, the control section of the sheet processing apparatus 400 comprising a microcomputer system performs serial communication with the control section of the image forming apparatus main body 500. By doing so, it is possible to grasp the size of the sheet inserted on the processing tray 410.

  Therefore, each time the sheet S is discharged (conveyed) from the image forming apparatus main body 500, the control unit (CPU 100) of the sheet processing apparatus 400 grasps the size of the sheet S and controls the offset motor 432, thereby controlling the offset roller 407. The amount of movement in the width direction can be controlled. As a result, the offset roller 407 moves by an amount corresponding to the size of the sheet S inserted on the processing tray 410, and the side portion of the sheet can be reliably brought into contact with the positioning wall 416.

  In this embodiment, since the sheet bundle stacked on the stack tray 421 constitutes a part of the processing tray 410, when the sheet bundle SA is discharged from the processing tray 410, the stack tray 421 is discharged. Is lowered by a stack tray raising / lowering motor (see FIG. 10) until the uppermost surface of the stacked sheet bundle substantially coincides with the processing tray 410.

  Next, the sheet processing operation of the sheet processing apparatus 400 of the present embodiment configured as described above will be described with reference to the flowcharts shown in FIGS.

  First, when an image forming operation by the image forming apparatus main body 500 is started, the CPU 100 (see FIG. 10) of the sheet processing apparatus 400 checks whether or not a sheet discharge signal is received from the image forming apparatus main body 500 (S100). ). If a sheet discharge signal is received (Y in S100), the pickup solenoid 433 is turned on (S110), and the offset roller 407 supported by the offset roller arm 406 is pulled up.

  Next, the conveyance motor 431 is turned on (S120), so that the conveyance roller 405 installed in the middle of the sheet discharge path can convey the sheet in the same direction as the sheet discharge direction of the image forming apparatus main body 500. Here, the leading edge of the first sheet passes through the inlet sensor 403 and turns on the inlet sensor 403 (Y in S130). Thereafter, the sheet reaches the conveying roller 405 and power is transmitted from the conveying roller 405 to the sheet. Then, when the sheet is separated from the paper discharge unit 208 (see FIG. 1) of the image forming apparatus main body 500 (Y in S140), the delivery of the sheet is completed.

  Next, while the sheet is conveyed to the processing tray 410 by the conveying roller 405, the pickup solenoid 433 is turned off before the sheet is completely removed from the conveying roller 405 (S150), and the offset roller 407 is landed on the sheet by its own weight. Let Thereafter, as shown in FIG. 6A, the sheet S is conveyed to a predetermined position by the offset roller 407 (S160). When the sheet S is conveyed to a predetermined position (Y in S160), the rotation of the conveyance motor 431 is stopped (S170), and the conveyance of the sheet S is stopped.

  Next, when the rotation of the offset roller 407 stops, the clamp solenoid 434 is turned on (S180), and the sheet clamp installed at the home position in the vicinity of the sheet trailing edge stopper 411 as shown in FIG. Open member 412. Thereafter, the conveyance motor 431 is rotated in the direction opposite to the conveyance direction, the sheet S is pulled back by the offset roller 407 (S190), and the sheet trailing edge is abutted against the sheet trailing edge stopper 411.

  Note that the rotation amount of the offset roller 407 when the trailing edge of the sheet abuts against the trailing edge stopper 411 takes into account the skew of the sheet S that is generated when the sheet S is fed from the image forming apparatus main body 500, and the sheet S is conveyed. The amount of rotation is such that it can be transported slightly more than the distance from the point of stopping and switching back to the sheet trailing edge stopper 411. That is, the offset roller 407 is reversely rotated for a predetermined time even after the sheet S is conveyed by a distance for contacting the sheet S with the sheet trailing edge stopper 411.

  Thereby, the sheet S can be reliably brought into contact with the sheet trailing edge stopper 411. When the sheet S is in contact with the sheet trailing edge stopper 411 while being reversely rotated for a predetermined time as described above, the offset roller 407 is idled (slip) on the sheet.

  Next, the sheet size to be discharged is checked based on the size information from the image forming apparatus main body 500 (S200), and the offset movement amount according to the size of the discharged sheet S, that is, the sheet S discharged onto the processing tray 410 is checked. The amount of offset movement, which is the amount of movement in the width direction of the sheet S, required for pressing the sheet to the positioning wall 416 is calculated (S210).

  Next, the offset motor 432 is driven to start the offset movement of the offset roller 407 (S220). Here, when the offset roller 407 moves in this way, the sheet S in contact with the offset roller 407 moves together with the offset roller 407 in the direction of the positioning wall 416 by the frictional force of the offset roller 407. At this time, the sheet clamp member 412 is rotated upward as shown in FIG. 8B so as not to be a load of movement of the sheet S.

  Then, by the offset movement operation of the offset roller 407, the sheet hits the positioning wall 416 as shown in FIG. 6C, and thereby the sheet S is aligned in the width direction. The offset roller 407 slides on the sheet S slightly after the sheet S abuts against the positioning wall 416 and stops. Thereafter, in order to correct the misalignment in the transport direction after the offset movement, an alignment operation is performed in which the offset roller 407 is reversed again and the sheet S is pulled back (S230). Alignment is complete.

  Next, when the alignment of the first sheet S is completed as described above, the pickup solenoid 433 is turned on (S240), and the offset roller 407 is lifted as shown in FIG. Turn off (S250). As a result, as shown in FIG. 7B, the sheet clamp member 412 is closed and the aligned sheet S is held and held. As a result, the first discharged sheet S is discharged next. It is possible to prevent the sheet from being carried by the used sheet.

  Next, as shown in FIG. 7B, the offset roller 407 is moved back to the home position via the rack and pinion by the offset motor 432 in a lifted state (S260).

  Next, it is checked whether or not the sheet S accommodated on the processing tray 410 is the last sheet corresponding to the last page of the copy document (S270), and based on the information sent from the image forming apparatus main body 500. When it is determined that the sheet is not the final sheet S (N in S270), the process returns to S100 and the next sheet discharge signal sent from the image forming apparatus main body 500 is received, and the final sheet S is stored in the processing tray 410. Until the above flow is repeated.

  With this configuration, the control unit (CPU) of the sheet processing apparatus 400 grasps the size of the sheet S each time the sheet S is discharged from the image forming apparatus main body 500 and is suitable for the sheet S. The offset movement amount is calculated. As a result, the sheet S in contact with the offset roller 407 is subjected to the alignment process based on the calculated movement amount and is aligned with the positioning wall 416.

  On the other hand, if it is determined that the sheet is the final sheet (Y in S270), a sheet bundle corresponding to the copy document is formed on the processing tray 410, so whether the stapling process is selected next. If it is selected (Y in S280), the staple unit 420 is driven, and the stapling process is executed at the staple position shown in FIG. 13 (S290).

  Next, when the stapling process is not selected (N in S280), or after the stapling process is completed, the sheet bundle discharging member 413 is replaced with the sheet bundle discharging motor 430 and the sheet bundle SA as shown in FIG. The sheet bundle SA is advanced in the direction of the stack tray 421 while being held by the sheet clamp member 412, and the sheet bundle SA is discharged (S300).

  Next, the stack tray 421 is moved (lowered) in accordance with the discharge operation of the sheet bundle SA (S310), and then the sheet bundle discharge member 413 is returned to the home position (S320). Thereafter, the conveyance motor 431 is stopped to stop the rotation of the conveyance roller 405 and the offset roller 407 (S330), the pickup solenoid 433 is turned off (S340), and the offset roller 407 is lowered to complete a series of processing. To do.

  Here, as described above, the rotation distance of the offset roller 407 when the sheet trailing edge abuts against the trailing edge stopper 411 is the distance from the point where the conveyance of the sheet S is stopped and switched back to the trailing edge stopper 411. In other words, the offset roller 407 is set to a predetermined amount even after the sheet S is conveyed by a distance that causes the sheet S to contact the trailing edge stopper 411 by the reverse rotation of the offset roller 407. By reversing the time, the sheet S can be reliably brought into contact with the rear end stopper 411.

  Thereby, the position of the sheet S in the sheet conveying direction can be stably aligned with a simple configuration that does not require many members. Further, since the sheet is not discharged so as to be skipped, the sheet can be stably conveyed with little fluctuation.

  In the present embodiment, the stapler unit 420 for binding the sheet bundle SA is fixed and disposed near the positioning wall 416. However, the present invention is not limited to this, and the stapler unit 420 is not limited to this. It may be movable, and may be movable in the sheet conveyance direction or width direction.

  The movable stapler unit 420 is used as described above, and the stapler unit 420 can be moved in the sheet conveyance direction or the width direction, so that the sheet bundle SA in the sheet conveyance direction or the width direction can be separated. Staple processing can be performed at a place or a plurality of places.

  Further, in this embodiment, the offset roller 407 and the offset motor 432 are used as the sheet conveying unit and the driving unit that constitute the moving unit that moves the sheet S in the width direction, but the present invention is not limited thereto. The same effect can be obtained even if the moving means is constituted by the sheet conveying means configured so that the member itself moves in the conveying direction and conveys the sheet, and the driving means for moving the sheet conveying means having such a configuration in the width direction. Is obtained.

  Further, in the present embodiment, the CPU performs control while reading the program written on the ROM (or RAM) shown in the flowcharts of FIGS. 11 and 12, but the hardware performs the processing on the control program. Even if configured, the same effect can be obtained.

  In the description so far, the case where the CPU of the control unit provided in the sheet processing apparatus provided in the image forming apparatus controls the operation of the offset roller or the like has been described. It may be provided in the forming apparatus main body, and its CPU may control the sheet processing operation of the offset roller or the like.

1 is a cross-sectional view illustrating a configuration of an image forming apparatus including a sheet treatment apparatus according to an embodiment of the present invention. The figure explaining the structure of the said sheet processing apparatus. The figure which shows a mode that a sheet | seat is discharged on the processing tray of the said sheet processing apparatus. The figure explaining the drive mechanism of the offset roller of the said sheet processing apparatus, and a conveyance roller. The figure explaining the drive mechanism of the offset roller of the said sheet processing apparatus, a conveyance roller, a sheet bundle discharge member, and a sheet clamp member. The figure explaining operation | movement of the said offset roller, and the movement of a sheet | seat accompanying it. The 1st figure explaining operation | movement of the said sheet clamp member. The 2nd figure explaining operation of the above-mentioned sheet clamp member. FIG. 4 is a diagram illustrating a state where the sheet bundle discharge member discharges a sheet bundle to a stack tray. The block diagram which shows the structure of the control part of the said sheet processing apparatus. 6 is a flowchart for explaining a part of the sheet processing operation of the sheet processing apparatus. 6 is a flowchart for explaining the remaining part of the sheet processing operation of the sheet processing apparatus. The figure which shows a mode that the sheet | seat offset by the said offset roller was stapled. The figure explaining the structure of the conventional sheet processing apparatus.

Explanation of symbols

200 Printer 400 Sheet Processing Device 407 Offset Roller 410 Processing Tray 411 Sheet Rear End Stopper 416 Positioning Wall 420 Stapler Unit 421 Stack Tray 432 Offset Motor 433 Pickup Solenoid 500 Image Forming Device Main Body A Image Forming Device S Sheet SA Sheet Bundle

Claims (9)

In a sheet processing apparatus comprising sheet stacking means for stacking sheets to be processed, forming a sheet bundle by aligning the sheets conveyed to the sheet stacking means, and processing the aligned sheet bundle,
A regulating member provided on the upstream side of the sheet stacking direction of the sheet stacking unit and regulating the position of the sheet in the sheet conveying direction;
Forward-reversible sheet conveying means for conveying the sheet conveyed to the sheet stacking means in the sheet conveying direction and then conveying the sheet in a direction opposite to the sheet conveying direction so as to contact the regulating member. ,
With
After the sheet is conveyed in the sheet conveying direction by the normal rotation of the sheet conveying means, the sheet is conveyed by the reverse rotation of the sheet conveying means so that the sheet abuts the regulating member, and the sheet is conveyed by the regulating member The sheet processing apparatus is characterized in that the sheet conveying means is reversely rotated for a predetermined time even after being conveyed so as to be in contact with the sheet.   The sheet processing apparatus according to claim 1, wherein the sheet conveying unit slips on the sheet after the sheet comes into contact with the regulating member.   The sheet processing apparatus according to claim 1, wherein the sheet conveying unit includes a cylindrical member.   The sheet processing apparatus according to claim 3, wherein an outer peripheral portion of the cylindrical member is formed of an elastic body.   When the sheet is conveyed to the sheet stacking unit, the sheet conveying unit is moved to a position that does not interfere with the conveyance of the sheet, and comes into contact with the sheet after the sheet is conveyed to the sheet stacking unit. The sheet processing apparatus according to claim 1, further comprising a position control unit that moves the position to the position. A side end regulating member that is provided at an end in the width direction perpendicular to the sheet conveying direction of the sheet stacking unit and regulates the position of the width direction end of the sheet;
A moving means for moving the sheet conveying means in the width direction in a state where the sheet conveying means is in contact with the sheet, and for bringing the sheet into contact with the side end regulating member;
With
Each time the sheet is conveyed to the sheet stacking means by the moving means, the sheet conveying means is moved in the width direction integrally with the sheet, and the sheet is brought into contact with the side end regulating member. The sheet processing apparatus according to any one of claims 1 to 5.   The sheet conveying means conveys the sheet in a direction opposite to the sheet conveying direction and makes contact with the regulating member, and the moving means moves the sheet integrally with the sheet conveying means in the width direction so as to form the side edge. The sheet processing apparatus according to claim 6, wherein the sheet is aligned by contacting the regulating member.   An image forming unit that forms an image on a sheet, and the sheet processing apparatus according to claim 1 that processes a sheet on which an image is formed by the image forming unit. Image forming apparatus. In an image forming apparatus that aligns sheets conveyed from an image forming unit to a sheet stacking unit to form a sheet bundle, and performs binding processing by the binding unit on the aligned sheet bundle.
A regulating member provided on the upstream side of the sheet stacking direction of the sheet stacking unit and regulating the position of the sheet in the sheet conveying direction;
Forward-reversible sheet conveying means for conveying the sheet conveyed to the sheet stacking means in the sheet conveying direction and then conveying the sheet in a direction opposite to the sheet conveying direction so as to contact the regulating member. ,
With
After the sheet is conveyed in the sheet conveying direction by the normal rotation of the sheet conveying means, the sheet is conveyed by the reverse rotation of the sheet conveying means so that the sheet abuts the regulating member, and the sheet is conveyed by the regulating member An image forming apparatus characterized in that the sheet conveying means is reversely rotated for a predetermined time after being conveyed so as to abut against the sheet.

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