JP2012041134A - Post-processing device and image forming system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a post-processing device capable of stably performing the alignment of paper on an intermediate stacker at the time of post-processing such as stapling processing into bigger-sized paper in a simple configuration.SOLUTION: The post-processing device includes a paper storage section that stores multiple pieces of paper, a post-processing mechanism section that performs post-processing on the multiple pieces of paper stored in the paper storage section, a paper discharge means that discharges the multiple pieces of paper on which the post-processing is performed from the paper storage section, a paper discharge tray that is loaded with the multiple pieces of paper discharged from the paper storage section, and an alignment means that aligns multiple pieces of paper stored in the paper storage section in the paper conveying direction and aligns multiple pieces of paper stored in the paper discharge tray in the paper-width direction perpendicular to the paper conveying direction.

Description

  The present invention relates to a post-processing apparatus and an image forming system that perform post-processing on a sheet on which an image has been formed, and more particularly to a post-processing apparatus and an image forming system that perform alignment processing on a sheet when performing post-processing.

  In a post-processing apparatus that performs post-processing such as stapling, punching, shifting, and folding on an image-formed sheet, a plurality of sheets are temporarily stored in a storage unit when the post-processing is performed, and the sheets are A device having a mechanism portion aligned in the transport direction and the paper width direction has been developed.

  In addition, an image forming system capable of high-speed processing in which a post-processing apparatus is connected to an image forming apparatus tends to be used as a light printing apparatus. And post-processing is required in a consistent manner.

  In Japanese Patent Application Laid-Open No. 2004-133620, an alignment mechanism is provided in a post-processing apparatus having a stapling function or the like, so that high-level alignment is performed on a paper discharge tray when discharging paper and an intermediate stacker during stapling processing. A post-processing device has been proposed (see Patent Document 1).

  FIG. 10 is an overall configuration diagram of an image forming system including a sheet stacking apparatus (post-processing apparatus) B as a post-processing apparatus disclosed in Patent Document 1.

  In FIG. 10, a sheet (paper) S formed by the image forming apparatus A and discharged from the discharge roller 7B is conveyed into the sheet stacking apparatus B and detected by an inlet sensor C1 installed in the conveyance path r1. The The conveyance path switching gate G2 switches the conveyance path of the sheet S, and switches between the conveyance path r2 to the upper discharge tray 10A and the conveyance path r3 to the main tray (discharge tray) 10B. The sheet S passing through the conveyance path r2 is discharged to the upper discharge tray 10A and stacked on the upper discharge tray 10A.

  The sheet S conveyed to the conveyance path r3 is first sent to the intermediate stacker 20 that is inclined so that the leading edge of the sheet in the sheet conveyance direction becomes higher. The intermediate stacker 20 functioning as a stack unit can temporarily retain (stack) a plurality of sheets S. Accordingly, the sheet S fed from the image forming apparatus A is not stored in the sheet stacking apparatus B without reducing the number of sheets discharged from the image forming apparatus A per unit time and without discharging the sheet S to the main tray 10B. To be able to accept. Further, by using the shift plate 20A in the intermediate stacker 20, it is possible to shift the sheet S discharged to the main tray 10B for each copy and to align with the sheet width direction perpendicular to the sheet conveyance direction. ing. Further, if the sheet is A4 size or smaller, such as A4 size or less, the trailing edge of the sheet is aligned by the inclination of the intermediate stacker 20, so that the sheet can be aligned in the sheet conveying direction. Note that the staple members 20D and 20E are operated when a staple process as a post-process is performed on a plurality of sheets S temporarily stacked in the intermediate stacker 20.

  The sheet S discharged from the intermediate stacker 20 is discharged and stacked on the main tray 10B. Reference numeral 30A in FIG. 10 denotes an alignment member that aligns the sheet S discharged to the main tray 10B in a direction perpendicular to the sheet conveyance direction (hereinafter referred to as a sheet width direction).

JP 2009-234727 A

  However, in the post-processing apparatus proposed in Patent Document 1, when the stapling process is performed on a large-sized sheet S such as A3 size, the sheet storage for storing the sheet S is long because the length of the sheet P in the sheet transport direction is long. The phenomenon that it does not fit on the part (intermediate stacker) 20 occurs. Therefore, when the trailing edge of the sheet S hits the sheet trailing edge receiving portion of the intermediate stacker 20, the leading edge of the sheet S protrudes downstream from a discharge roller (without reference numeral) that discharges the sheet S to the discharge tray 10B. The leading edge of the sheet hangs down from the discharge roller pair 21. Therefore, even if the intermediate stacker 20 is inclined as shown in the figure, there is no guarantee that the trailing edge of the sheet S will abut against the trailing edge receiving portion of the intermediate stacker 20, and the alignment of the sheet S in the sheet conveyance direction is insufficient. There is a problem that the stapling process must be performed in a difficult state. In order to prevent the large-size sheet S from drooping from the paper discharge roller pair 21, it is necessary to lengthen the overall length of the intermediate stacker 20, and there is a problem that the apparatus size of the sheet stacking apparatus B becomes too large.

  An object of the present invention is to solve the above-described problems and to align sheets on an intermediate stacker during post-processing such as stapling for large-sized sheets, while having a simple configuration with a relatively compact device. It is an object of the present invention to provide a post-processing apparatus that can perform with stable performance, and an image forming system including the post-processing apparatus.

  The object is achieved by the following invention.

1. A paper storage section for storing a plurality of paper sheets;
A post-processing mechanism for performing post-processing on a plurality of sheets stored in the sheet storage unit;
A sheet discharge means for discharging a plurality of sheets after the post-processing from the sheet storage unit;
A paper discharge tray for stacking a plurality of sheets discharged from the paper storage section;
The plurality of sheets stored in the sheet storage unit are aligned in the sheet conveying direction, and the plurality of sheets stacked on the paper discharge tray are aligned in the sheet width direction perpendicular to the sheet conveying direction. Alignment means to perform,
A post-processing apparatus comprising:

  An image forming system comprising the post-processing device described in 2.1.

  By using the post-processing apparatus according to the present invention, an intermediate stacker for performing post-processing such as stapling without increasing the size of the post-processing apparatus even for a large-sized sheet with a simple configuration. The above alignment in the paper transport direction can be performed properly.

1 is an overall configuration diagram of an image forming system including an image forming apparatus A, an automatic document feeder DF, and a post-processing apparatus B. FIG. It is the schematic for demonstrating the structure and operation | movement of the intermediate stacker 20 as a paper storage part which concerns on this invention, and its surrounding mechanism part. It is a block diagram of the control system which concerns on the control part 101 of this invention. It is a schematic diagram for explaining the operation and configuration of alignment members 30A and 30B for aligning sheets P stacked on the sheet discharge tray 10B in the sheet width direction. It is the schematic which shows the mechanism of the detection means which detects the height (angle) of the alignment members 30A and 30B which rotate and change with rotation of the alignment member rotation drive motor M1. FIG. 6 is a schematic cross-sectional view for explaining a configuration and operation for aligning the paper P stored in the intermediate stacker 20 in the paper transport direction using the alignment members 30A and 30B according to the present invention. FIG. 6 is a schematic diagram for explaining an operation of aligning sheets P shifted and stacked on the sheet discharge tray 10B for each sheet bundle. It is a front view of 30 A of 1st alignment members, and is an expanded block diagram of 1st alignment member 30A in the position of a continuous line in Fig.4 (a). It is a figure explaining the alignment effect | action in embodiment of alignment member 30A, 30B which concerns on this invention. 1 is an overall configuration diagram of an image forming system including a sheet stacking device (post processing device) B as a post processing device disclosed in Patent Document 1. FIG.

  Hereinafter, the present invention will be described based on an embodiment, but the present invention is not limited to the embodiment.

  FIG. 1 is an overall configuration diagram of an image forming system including an image forming apparatus A, an automatic document feeder DF, and a post-processing apparatus B.

  An image forming apparatus A shown in FIG. 1 includes an image reading unit 1, an image processing unit 2, an image writing unit 3, an image forming unit 4, and the like. An automatic document feeder DF is mounted on the upper part of the image forming apparatus A, and a post-processing apparatus B is connected to the left side of the image forming apparatus A.

  The document a placed on the document table of the automatic document feeder DF is conveyed in the direction of the arrow, and an image sensor 1A in the image reading unit 1 reads an image on one or both sides of the document a. The analog signal photoelectrically converted by the image sensor 1A is subjected to analog processing, A / D conversion, shading correction, image compression processing, and the like in the image processing unit 2, and then sent to the image writing unit 3. In the image writing unit 3, the output light from the semiconductor laser is applied to the photosensitive drum 4A of the image forming unit 4, and an electrostatic latent image is formed on the photosensitive drum 4A.

  In the image forming unit 4, processes such as charging, exposure, development, transfer, separation, and cleaning are performed. An image is transferred by the transfer unit 4B to the paper P fed from the paper feed cassettes 5A to 5C. The paper P on which the image has been transferred is fixed by the fixing unit 6 and sent from the discharge roller 7B to the post-processing apparatus B. Alternatively, the paper P is sent to the double-sided paper feeding portion 7A by the transport path switching gate G1, and an image is also formed on the back side by the image forming portion 4, and sent to the post-processing device B from the discharge roller 7B.

  The control unit 101 that controls the operation of each unit of the post-processing apparatus B and the image forming apparatus A according to the present invention is disposed inside the image forming apparatus A.

  The post-processing apparatus B discharges the paper P sent from the image forming apparatus A to the upper paper discharge tray 10A and the paper discharge tray (stacking unit) 10B, and loads the paper P on the upper paper discharge tray 10A and the paper discharge tray 10B. To do. The post-processing apparatus B has a shift function, a stapling function, and the like. For the paper P that is temporarily stored in the post-processing apparatus B or stacked on the paper discharge tray 10B, a shift process or stapling for each copy is performed. Post-processing such as processing is performed.

  The paper P sent to the post-processing apparatus B is detected by an inlet sensor C1 installed in the transport path r1. By using the entrance sensor C1, it is possible to detect that the paper P is sent from the image forming apparatus A to the post-processing apparatus B.

  The transport path switching gate G2 switches the transport path of the paper P, and switches between the transport path r2 to the upper discharge tray 10A and the transport path r3 to the discharge tray 10B. The paper P passing through the transport path r2 is discharged to the upper paper discharge tray 10A and stacked on the upper paper discharge tray 10A.

  The paper P passing through the transport path r3 is first fed into the intermediate stacker 20. The intermediate stacker 20 as a sheet storage unit according to the present invention temporarily stores (stacks) a plurality of sheets P. That is, the sheet P fed from the image forming apparatus A is not reduced by the intermediate stacker 20 without decreasing the number of prints per unit time discharged from the image forming apparatus A and without directly discharging the sheet P to the sheet discharge tray 10B. It can be temporarily received in the post-processing apparatus B. In addition, by using the shift plate 20A (20B) in the intermediate stacker 20, it is possible to shift the paper P discharged to the paper discharge tray 10B for each copy. When stapling processing is performed on a plurality of sheets P that are temporarily stacked in the intermediate stacker 20, the stapling processing unit 40 as a post-processing mechanism unit is operated.

  After the post-processing, the paper P discharged from the intermediate stacker 20 is discharged to the paper discharge tray 10B and stacked. In FIG. 1, 30A and 30B are alignment members included in the alignment means according to the present invention, and align the paper P discharged to the paper discharge tray 10B. The alignment operation of the alignment members 30A and 30B in the intermediate stacker 20 and the paper discharge tray 10B will be described later.

  Next, the configuration of the intermediate stacker 20 and its surroundings will be described with reference to FIG.

  FIG. 2 is a schematic diagram for explaining the configuration and operation of the intermediate stacker 20 as a paper storage unit according to the present invention and the surrounding mechanical units.

  2, the intermediate stacker 20 has shift plates 20A and 20B, a paper discharge belt 20C as one paper discharge means, and a paper rear end receiving member 20F that receives the rear end of the paper P in the paper transport direction. . In addition, a stapling processing unit 40 that performs stapling processing on the paper P is provided around the intermediate stacker 20, and further, the other side that discharges the paper P from the intermediate stacker 20 downstream of the intermediate stacker 20 in the paper transport direction. A paper discharge roller pair 21 is disposed as a paper discharge means.

  The shift plates 20A and 20B move the paper P stored in the intermediate stacker 20 to a predetermined position in the paper width direction by a link mechanism and a drive motor (not shown), and reciprocate in the paper width direction. On the other hand, shift and alignment in the paper width direction are performed as necessary.

  The paper discharge belt 20C as one paper discharge means according to the present invention is wound and rotated around a pair of rollers (without reference numerals) as shown. A paper discharge claw 20C1 is attached to the surface of the paper discharge belt 20C. The plurality of sheets P that are stored in the intermediate stacker 20 and have been post-processed by the staple processing unit 40 or the like have their sheet trailing edges abutted against the sheet discharge claw 20C1 that moves as the sheet discharge belt 20C rotates, and the sheet conveyance direction It is conveyed to. Thereafter, the plurality of sheets P are sandwiched between the pair of discharge rollers 21 and discharged from the intermediate stacker 20. A motor (not shown) is connected to one roller (drive roller) of the pair of rollers, and is driven by a command from the control unit 101 to rotationally drive one of the rollers.

  The paper discharge roller pair 21 as another paper discharge means according to the present invention includes a drive roller 21A and a driven roller 21B that is in pressure contact therewith. The driven roller 21B is rotatably held by a swingable swing arm (not indicated by reference numeral), and the swing arm is connected to a paper discharge roller interval adjusting motor M5. The discharge roller interval adjustment motor M5 is driven by a command from the control unit 101, rotates the swing arm by a predetermined angle according to the number and thickness of the sheets P stored in the intermediate stacker 20, and drives the drive roller 21A. And the distance (nip) between the driven roller 21B and the driven roller 21B. A configuration for rotating the swing arm at a predetermined angle will be described later. The drive roller 21A is connected to a paper transport motor M3 (not shown) and is driven to rotate by a command from the control unit 101. By adjusting the frictional force between the paper discharge roller pair 21 and the paper P to an appropriate value by changing the roller spacing of the paper discharge roller pair 21 according to the thickness or number of paper P, the alignment members 30A and 30B The alignment in the paper transport direction is performed properly.

  In addition, as shown in FIG. 2, a large paper sheet P such as A3 size, which will be described later, protrudes from the paper discharge roller pair 21 when the paper sheet P is stored in the intermediate stacker 20. Accordingly, when performing shift processing or alignment processing in the paper width direction on such a large size paper P using the shift plate 20A (20B), it is necessary to open the roller interval of the paper discharge roller pair 21. is there.

  The sheet trailing edge receiving member 20 </ b> F according to the present invention is disposed on the upstream side of the intermediate stacker 20 in the sheet conveyance direction, and receives the trailing edge of the sheet P stored in the intermediate stacker 20. Further, for example, a rack RC is fixed to the sheet trailing edge receiving member 20F as means for moving the position of the sheet trailing edge receiving member 20F. The rack RC meshes with the pinion PN, and the pinion PN is connected to the rear end receiving member moving motor M4. The trailing edge receiving member moving motor M4 is controlled by the control unit 101 to move the trailing edge receiving member 20F, and the movement amount is a predetermined value according to the size of the sheet P stored in the intermediate stacker 20. To be determined.

  By setting the amount of movement of the sheet trailing edge receiving member 20F to a predetermined value according to the size of the sheet P, the position of the leading end of the sheet P stored in the intermediate stacker 20 is changed, and the alignment members 30A and 30B described later are used. It is set to be a position suitable for alignment in the paper transport direction. That is, only the angle adjustment of the alignment members 30A and 30B that rotate about the rotation axis AX limits the alignment range in the sheet conveyance direction to the sheet P, but by moving the sheet rear end receiving member 20F. The degree of freedom is given to make the matching range wider.

  The predetermined rotation angle of the swing arm by the paper discharge roller interval adjusting motor M5 and the predetermined movement amount of the paper rear end receiving member 20F by the rear end receiving member moving motor M4 are respectively determined by the experiment. The optimum value calculated corresponding to the thickness is set as the predetermined value. This predetermined value is stored in advance in the memory of the control unit 101 as a program, and is controlled so as to be taken out as needed via the control unit 101.

  By setting the rotation angle around the rotation axis AX according to the sheet size of the alignment members 30A and 30B of the present invention, the alignment in the sheet conveyance direction is appropriately performed for the plurality of sheets P stored in the intermediate stacker 20. Done.

  Further, by setting the movement amount of the position corresponding to the paper P size of the paper trailing edge receiving member 20F of the present invention, the paper according to various sizes of the paper P in the limited rotation range of the alignment members 30A and 30B. The alignable area is widened so that the alignment in the transport direction is possible.

  Further, the roller interval of the paper discharge roller pair 21 according to the present invention is changed according to the thickness or number of sheets P stored in the intermediate stacker 20 to adjust the frictional force between the paper discharge roller pair 21 and the paper P. Thus, the alignment operation in the sheet conveyance direction by the alignment members 30A and 30B can be stabilized.

  FIG. 3 is a block diagram of a control system related to the control unit 101 in the post-processing apparatus B of the present invention.

  In FIG. 3, the control unit 101 includes an inlet sensor C1, a paper discharge sensor C2, a sheet number information input unit MN, a counter CT, a sheet size detection unit SS, a sheet thickness detection unit TS, an alignment member rotation angle detection unit RS, and the like. Receive various information from Based on the information, the operations of the alignment member rotation drive motor M1, the alignment member sliding drive motor M2, the paper conveyance motor M3, the trailing edge receiving portion movement motor M4, the discharge roller interval adjustment motor M5, and the like are controlled. . Further, the control unit 101 performs control by communicating various information with the control unit of the image forming apparatus A.

  Next, a configuration and operation for aligning the paper P discharged to the paper discharge tray 10B in the paper width direction by the alignment members 30A and 30B will be described.

  FIG. 4 is a schematic diagram for explaining the operation and configuration of the alignment members 30A and 30B that align the sheets P stacked on the sheet discharge tray 10B in the sheet width direction. 4A is an enlarged view around the alignment members 30A and 30B, and FIG. 4B is a plan view of the paper discharge tray 10B as viewed from above.

  The alignment means according to the present invention has a pair of sliding mechanism portions 30 and a pair of alignment member sliding drive motors M2 as alignment member sliding drive means. One sliding mechanism portion 301 of the pair of sliding mechanism portions 30 includes a first alignment member 30A, a rotation axis AX as an alignment member holding shaft, and an alignment member rotation drive as an alignment member rotation drive means. A motor M1. Similarly, the other sliding mechanism 302 includes a second alignment member 30B, a rotation axis AX as an alignment member holding shaft, and an alignment member rotation drive motor M1 as an alignment member rotation drive means. It is.

  The pair of sliding mechanism portions 30 on which the alignment members 30A and 30B are respectively mounted are disposed so as to be movable in the paper width direction, and are reciprocated in the paper width direction by driving of the pair of alignment member sliding drive motors M2, respectively. The mechanism for moving the pair of sliding mechanism sections 30 in the paper width direction uses a known link mechanism (not shown), and the rotation operation of the pair of alignment member sliding drive motors M2 is performed using a belt or wire (not shown). Converted to linear motion in the paper width direction.

  The height of the upper surface of the paper P stacked on the paper discharge tray 10B is detected by a sensor (not shown), and the paper discharge tray 10B is moved up and down so that the upper surface of the paper P is always at a constant height. The vertical movement of the paper discharge tray 10B is performed by driving a motor (not shown).

  Above the discharge tray 10B, a pair of alignment members 30A and 30B that are in contact with and separated from the side edges of the sheet P by reciprocating movement of the pair of sliding mechanism sections 30 in the sheet width direction are installed (alignment). The member 30A is a first alignment member, and the alignment member 30B is a second alignment member). The alignment members 30A and 30B can rotate (reciprocate) in the rotation direction about the rotation axis AX. As described above, the operation for aligning the sheets P is an operation for aligning a plurality of sheets P stacked on the sheet discharge tray 10B in the sheet width direction at the sheet alignment position indicated by the solid line in FIG. Then, there is an operation of aligning the plurality of sheets P stored in the intermediate stacker 20 in the sheet transport direction. When the alignment operation for the paper P on the intermediate stacker 20 or the paper discharge tray 10B is not performed, the alignment members 30A and 30B are moved to the upward retracted position indicated by the broken line in FIG.

  When aligning the paper P on the paper discharge tray 10B, the pair of sliding mechanism portions 30 are moved by the driving of the pair of alignment member sliding drive motors M2, and the alignment members 30A and 30B are shown in FIG. It is reciprocated in the sheet width direction of i and j shown (either of the alignment members 30A and 30B is reciprocated according to the alignment position). Then, the sheet P is aligned in the sheet width direction by hitting at least one sheet side end of the sheet P on which the sheet side end alignment surfaces of the alignment members 30A and 30B are stacked. The reciprocating movement of the alignment members 30A and 30B (a pair of sliding mechanism portions 30) is performed by a pair of alignment member sliding drive motors M2 shown in FIG. The driving force of the pair of alignment member sliding drive motors M <b> 2 is transmitted to the sliding mechanism unit 30 by the mechanism. Due to the reciprocal movement of the pair of sliding mechanism portions 30, the alignment members 30A and 30B reciprocate.

  A paper discharge sensor C2 installed in the transport path detects the paper P discharged to the paper discharge tray 10B, and the number of sheets P discharged based on the detection signal from the paper discharge sensor C2 is built in the control unit 101. Counter CT is calculated. When the calculation result reaches a predetermined value and the sheet P has to be aligned at another position for the shift process, the control unit 101 includes two alignment member rotation drive motors M1 and a pair of alignment member sliding drive motors. The operation of M2 is controlled to move the pair of sliding mechanism portions 30 to different positions. As the pair of sliding mechanism portions 30 move, the alignment members 30A and 30B are moved.

  In the present embodiment, the pair of alignment members 30A and 30B are mounted on the pair of sliding mechanism portions 30 and reciprocated in the paper width direction by the pair of alignment member sliding drive motors M2, respectively. However, it is good also as a structure which does not use the sliding mechanism part 30. FIG. That is, the alignment members 30A and 30B are configured to be rotatable and slidable with respect to the rotation axis AX, and the alignment members 30A and 30B are respectively slid in the paper width direction by a pair of fixed alignment member sliding drive motors M2. It is the composition of letting. In this configuration, the alignment member rotation drive motor M1 is also fixed, and the alignment members 30A and 30B are rotated by the link mechanism.

  On the other hand, the movement of the alignment members 30A and 30B to a plurality of alignment (alignment in the sheet conveying direction) and the movement to the upper retreat position by the rotation of the two alignment member rotation drive motors M1 is performed by a photoelectric sensor. This is performed based on a signal output from the member rotation angle detection means RS. The operation of aligning the paper P stored in the intermediate stacker 20 in the paper transport direction will be described later with reference to FIG.

  FIG. 5 is a schematic view showing a mechanism of a detecting means for detecting the height (angle) of the alignment members 30A and 30B that are rotated and changed by the rotation of the alignment member rotation drive motor M1. The encoder RD is fixed to the rotation axis AX of the alignment members 30A and 30B, and the alignment member rotation angle detection means RS detects the rotation position of the encoder RD.

  Further, the alignment members 30A and 30B are reciprocated in the paper width direction by the rotation of the pair of alignment member sliding drive motors M2, but the position of the alignment members 30A and 30B in the paper width direction is also the encoder RD shown in FIG. And the alignment member rotation angle detection means RS. That is, a pulse motor may be used for the pair of alignment member sliding drive motors M2, and the amount of movement may be calculated by converting the signal from the encoder RD into a pulse. However, it is needless to say that not only this method but also other position detection sensors may be used.

  On the other hand, as described with reference to FIG. 2, the discharge roller interval adjustment motor M5 is driven by a command from the control unit 101 and moves the swing arm by a predetermined angle according to the number and thickness of the sheets P in the intermediate stacker 20. The interval between the driving roller 21A and the driven roller 21B is changed. At this time, a mechanism for setting the rotation angle of the alignment members 30A and 30B shown in FIG. 5 can also be used for the rotation angle of the swing arm to be rotated. Description of is omitted.

  FIG. 6 is a schematic cross-sectional view for explaining the configuration and operation for aligning the paper P stored in the intermediate stacker 20 in the paper transport direction using the alignment members 30A and 30B according to the present invention. The target sheets are large-sized (for example, A3 size) sheets P1 and P2 (here, P1 <P2), and when the sheet rear end comes into contact with the rear end receiving member 20D of the intermediate stacker 20, the front end of the sheet Is a sheet of a size protruding from the sheet discharge roller pair 21 as shown.

  According to the alignment members 30A and 30B according to the present invention, it is possible to align the paper P stored in the intermediate stacker 20 in the paper transport direction by using a movement that rotates about the rotation axis AX. This alignment operation is performed by rotating the alignment members 30A and 30B in a plurality of alignment ranges that change according to the paper size. This operation range is determined as a rotation operation range of the alignment member rotation drive motor M1 according to the sheet size detected by the sheet size detection unit SS, and is based on a signal output from the alignment member rotation angle detection unit RS. A reciprocating motion is performed.

  As shown in FIG. 6, the alignment members 30 </ b> A and 30 </ b> B are brought into contact with and separated from the leading ends of the sheets P <b> 1 and P <b> 2 stored in the intermediate stacker 20 by a rotation operation (reciprocation operation) that fits and rotates on the rotation axis AX. A paper tip alignment portion CV having a curved surface or a polygonal surface is formed at the contact portion. The sheet leading edge aligning portion CV is formed at the side edge of the sheet side end aligning surface of the aligning members 30A and 30B (the surface that contacts and separates from the sheet end surface of the sheet P on the discharge tray 10B and aligns the sheet P in the sheet width direction). It is formed. In FIG. 6, reference symbols Pa and Pb on the cross-sectional view are contact points of the leading edge of the sheet P1 or P2 with respect to the sheet leading edge aligning portion CV, and Sa and Sb are sheet leading edge aligning portions CV at the contacting points Pa and Pb. Represents the tangent to the curved surface. θ represents an angle at which the sheets P1 and P2 contact the tangent lines Sa and Sb.

  FIG. 6A illustrates a case where the sheets stored in the intermediate stacker 20 are the sheets P1 having a small size at the leading end of the sheet from the discharge roller pair 21 and the alignment members 30A and 30B are rotated. FIG. 10 is a schematic diagram for explaining an alignment operation in the paper transport direction when contacting and separating from the leading edge. Similarly, FIG. 6B shows a case where the sheet stored in the intermediate stacker 20 is a sheet P2 having a large sheet tip protrusion amount from the paper discharge roller pair 21, and the alignment members 30A and 30B are moved to the sheet leading edge. It is the schematic for demonstrating the alignment operation | movement at the time of contact / separation. FIG. 6C is a partially enlarged view for explaining the positional relationship between the sheet leading edge aligning portion CV of the aligning members 30A and 30B and the sheets P1 and P2 contacting the sheet leading edge aligning portion CV.

  In FIG. 6A, the sheet P1 in which the leading end of the sheet protrudes from the paper discharge roller pair 21 is smaller than the sheet P2, the contact point Pa of the leading end of the sheet P1 in the sheet leading end alignment portion CV is closer to the rotation axis AX than the sheet P2. The contact angle θ is set to be substantially a right angle.

  In FIG. 6B, the large sheet P2 has a larger amount of protrusion from the sheet discharge roller pair 21 at the leading end of the sheet than the sheet P1, and accordingly, the contact point Pb is farther from the rotation axis AX than the sheet P1. It becomes. However, the abutting angle θ is set to be a substantially right angle value as in the paper P1.

  In FIG. 6C, the positional relationship when the leading edge of the paper P2 protruding from the paper discharge roller pair 21 (not shown) comes into contact with the paper leading edge alignment portion CV of the alignment members 30A and 30B is indicated by a solid line, and the leading edge of the paper P1 is The positional relationship when abutting against the sheet leading edge alignment portion CV is indicated by a broken line. As shown in FIG. 6C, the distance L1 from the rotation axis AX of the contact point Pa when the leading edge of the paper P1 comes into contact with the paper leading edge alignment portion CV is such that the leading edge of the paper P2 corresponds to the paper leading edge alignment portion CV. It is shorter than the distance L2 of the contact point Pb at the time of contact by ΔL. In addition, the angle formed by the end faces of the alignment members 30A and 30B from the sheet leading edge alignment portion CV toward the vicinity of the rotation axis AX changes as indicated by the solid line and the broken line in FIG. For this reason, when the sheet leading edge alignment portion CV is formed in a straight line, the contact angle with respect to the sheets P1 and P2 discharged at a substantially constant angle is different, and an appropriate (substantially right angle) contact angle is obtained. Must not. However, since the shape of the paper leading edge alignment portion CV according to the present invention is formed in a curved surface or a polygonal surface, the size varies even if the angle formed by the end surface from the paper leading edge alignment portion CV toward the vicinity of the rotation axis AX changes. The angle θ formed between the leading edge of the paper P and the paper leading edge alignment portion CV is always substantially a right angle.

  As described above, the sheet leading edge aligning portion CV of the aligning members 30A and 30B has a contact angle θ even if the abutting position of the sheet leading edge aligning portion CV with respect to the sheet leading edge changes due to the difference in the length of the sheets P1 and P2. Is formed on a curved surface or a polygonal surface such that the sheet leading edge alignment portion CV is substantially perpendicular. In other words, the large paper sheets P1 and P2 protrude from the paper discharge roller pair 21 and are difficult to align in the paper conveyance direction, but the paper front edge aligning portion CV is in contact with the paper front edge at a right angle. By using the rigidity (waist) of the paper, proper alignment is possible. For this reason, when the sheet leading edge aligning portion CV contacts the leading ends of the sheets P1 and P2, the leading ends of the sheets P1 and P2 may be displaced from the contact point Pa of the sheet leading end aligning section CV or buckled from the middle of the sheet. And properly aligned in the paper transport direction. In the alignment operation in the sheet conveying direction, the two alignment member rotation drive motors M1 reciprocate at a predetermined rotation angle to rotate the alignment members 30A and 30B to the left and right, and the sheet leading edge alignment unit CV moves the sheets P1 and P2. This is done by moving to and away from the tip.

  Since the shape of the sheet leading edge aligning portion CV of the aligning members 30A and 30B according to the present invention is formed so that the abutting angle θ of the sheet leading edge is substantially a right angle, the sheet is displaced or seated even on a large size sheet. The alignment in the paper transport direction can be performed properly without bending.

  Next, the operation in the sheet width direction of the alignment members 30A and 30B when the shift operation is added to the alignment operation in the sheet width direction described in FIG. 4 will be described with reference to FIG. In the following description, a group of sheets formed of the sheets P and shifted in the sheet discharge tray 10B are referred to as sheet bundles PP1, PP2, and PP3.

  FIG. 7 is a schematic diagram for explaining the operation of aligning the sheets P shifted and stacked on the sheet discharge tray 10B for each sheet bundle.

  As shown in step SP1 of FIG. 7, first, the sheet bundle PP1 shifted by the shift plates 20A and 20B of the intermediate stacker 20 is stacked on the left side of the sheet discharge tray 10B. Each time the paper P constituting the paper bundle PP1 is discharged to the paper discharge tray 10B, the paper bundle PP1 is aligned by the alignment members 30A and 30B, so that the ends of the paper P constituting the paper bundle PP1 are aligned.

  If it is determined that the sheet bundle PP1 has reached the predetermined number of sheets by using the signal of the sheet discharge sensor C2 installed on the upstream side in the sheet conveyance direction of the sheet discharge tray 10B, as shown in step SP2, the alignment member 30A , 30B rotate upward and move to the right side of the paper discharge tray 10B. The alignment members 30A and 30B are rotated upward by two alignment member rotation drive motors M1, and the alignment members 30A and 30B are moved in the paper width direction by a pair of alignment member sliding drive motors M2. The moving distance of the alignment members 30A and 30B in the paper width direction is the same as the distance that the shift plates 20A and 20B of the intermediate stacker 20 move in the paper width direction for shifting.

  When the alignment members 30A and 30B move by a predetermined distance, as shown in step SP3, the first alignment member 30A rotates downward to a position where the lower end of the first alignment member 30A contacts the upper surface of the sheet bundle PP1. The second alignment member 30B rotates downward. Then, as shown in step SP4, the sheet bundle PP2 shifted by the shift plates 20A and 20B of the intermediate stacker 20 is stacked on the sheet bundle PP1. Similarly to the sheet bundle PP1, since the sheets P constituting the sheet bundle PP2 are aligned by the alignment members 30A and 30B each time the sheets P are discharged to the sheet discharge tray 10B, the ends of the sheets P constituting the sheet bundle PP2 are aligned. Yes.

  Further, when discharging the paper P to the left side of the paper discharge tray 10B and executing the alignment operation, the alignment members 30A and 30B are rotated upward, horizontally moved, and rotated downward as shown in steps SP5 and SP6. . Then, as shown in step SP7, the sheet bundle PP3 shifted by the shift plates 20A and 20B is stacked on the sheet bundle PP2. By such a procedure, the paper P is shifted and aligned at the two left and right positions of the post-processing apparatus B.

  As described above, when the alignment members 30A and 30B move in the paper width direction of the post-processing apparatus B and the alignment operation is performed by the alignment members 30A and 30B, before the paper P is discharged to the paper discharge tray 10B. The horizontal movement of the alignment members 30A and 30B must be completed. In addition, it takes a certain time for the alignment members 30A and 30B to move in the horizontal direction. Therefore, when a print job for continuously feeding the paper P to the post-processing apparatus B is executed, the paper P is not discharged to the paper discharge tray 10B in some cases in order to secure the horizontal movement time of the alignment members 30A and 30B. It is necessary to stack a plurality of sheets P on the intermediate stacker 20. However, when the sheet bundle is composed of one sheet, it is mixed with the sheets P constituting the other sheet bundle, so that one sheet P can be temporarily stacked on the intermediate stacker 20. In addition, it is not possible to ensure the horizontal movement time of the alignment members 30A and 30B. Therefore, in consideration of the number of prints constituting the sheet bundle, when the number of prints per copy to be shifted is 1, control is performed so that the alignment operation by the alignment members 30A and 30B is not executed.

  Next, an example of a detailed configuration of the pair of alignment members 30A and 30B according to the present invention will be described with reference to FIG.

  FIG. 8 is a front view of the first alignment member 30A, and is an enlarged configuration diagram of the first alignment member 30A located at a solid line in FIG. 4A.

  The first alignment member 30A includes a first alignment portion 30A1 that is rotatably supported by the rotation axis AX, and a second alignment portion 30A2 that is supported by the first alignment portion 30A1. As shown in the figure, the second alignment portion 30A2 is provided in a recess provided in the first alignment portion 30A1, and is slidable with respect to the first alignment portion 30A1 between a position indicated by 30A2a and a position indicated by 30A2b. It is. The first alignment portion 30A1 is provided with a long groove 30A3, and the pin 30A4 provided in the second alignment portion 30A2 is fitted into the long groove 30A3. The second alignment portion 30A2 moves up and down relatively with respect to the first alignment portion 30A1 by the guide by the long groove 30A3 and the pin 30A4.

  FIG. 8A shows a state in which the first alignment member 30A is not in contact with either the paper discharge tray 10B or the top surface of the paper P stacked on the paper discharge tray 10B. The matching portion 30A2 is lowered to its lowest position by its own weight. FIG. 8B shows a state in which the first alignment member 30A is placed on the paper P stacked on the paper discharge tray 10B.

  As shown in FIG. 8B, when the first alignment member 30A is placed on the upper surface of the sheet P, the first alignment unit 30A1 and the second alignment unit 30A2 are stacked on the sheet discharge tray 10B. Always in contact. Further, as shown in FIG. 9, the first aligning member 30A has a lower end of the first aligning portion 30A1 at the point Q1 and the end of the sheet Pup as shown in FIG. While regulating the edge, the lower end of the second alignment portion 30A2 regulates the edge of the paper Pup at the point Q2.

  Similarly to the first alignment member 30A, the second alignment member 30B is also the first alignment portion 30A1 (30B1 for the second alignment member) and the second alignment portion 30A2 (also 30B2) shown in FIG. The configuration and operation thereof are the same as those of the first alignment member 30A. Therefore, explanation is omitted.

  FIG. 9 is a view for explaining the alignment operation in the embodiment of the alignment members 30A and 30B according to the present invention.

  In FIG. 9, when the second alignment member 30 </ b> B contacts and separates from the edge Q <b> 0 of the paper Pup, the first alignment member 30 </ b> A performs position regulation at two different points in the paper discharge direction W. That is, the lower end side portion of the first alignment portion 30A1 regulates the position of the edge of the paper Pup at the point Q1 in FIG. 9, and the lower end side portion of the second alignment portion 30A2 is the end of the paper Pup at the point Q2 in FIG. The position of the edge is regulated.

  In the present embodiment, the first alignment member 30A is in contact with the two edges of the paper Pup. However, the alignment members 30A and 30B are configured to contact only one edge on each of the left and right sides of the paper Pup. When the contact structure is adopted, a problem occurs when the curl of the paper is large. That is, when the paper curls, a difference occurs in the height of the first alignment member 30A and the second alignment member 30B that are in contact with the edge of the paper, and as a result, the first alignment member 30A (or the second alignment member 30A). A difference is caused in the contact position of the member 30B) with respect to the paper Pup in the paper discharge direction W. This is because the alignment members 30A and 30B are configured to swing around the rotation axis AX, so that the horizontal position changes when the height of contact with the paper Pup changes. If the alignment members 30A and 30B are in contact with the edge of the paper Pup only at one place on each of the left and right sides, and the left and right contact positions change, the paper Pup is moved in the paper discharge direction W by the alignment operation. There is a risk of tilting left or right.

  However, according to the present embodiment, even when the sheet bundle PP on which the alignment members 30A and 30B are placed is curled, and the restriction positions of the alignment members 30A and 30B on the sheet Pup are shifted to the positions of Q1a and Q2a. The restriction positions are the two points shown in FIG. 9, and this problem does not occur.

7B discharge roller 10B discharge tray (main tray)
20 intermediate stacker 20A, 20B shift plate 20C paper discharge belt 20C1 paper discharge claw 20F paper rear end receiving member 21 paper discharge roller pair 21A drive roller 21B driven roller 30 pair of sliding mechanism parts 301 one sliding mechanism part 302 the other Sliding mechanism 30A First alignment member 30B Second alignment member 40 Staple processing section A Image forming apparatus B Post-processing apparatus (sheet stacking apparatus)
P, P1, P2, Pup Paper S Sheet θ Abutting angle (at the front end of the paper) AX Rotating shaft (Alignment member holding shaft)
C1 inlet sensor C2 paper discharge sensor CT counter CV paper leading edge alignment unit M1 alignment member rotation drive motor (alignment member rotation drive means)
M2 alignment member sliding drive motor (alignment member sliding drive means)
M3 Paper transport motor M4 Rear end receiving member moving motor M5 Paper discharge roller interval adjustment motor MN Paper number information input means PN Pinion Pa, Pb Current contact RC rack RD Encoder RS Alignment member rotation angle detection means SS Paper size detection means Sa, Sb Tangent (with respect to curved surface) TS Paper thickness detection means 101 Control unit PP1, PP2, PP3 Paper bundle

Claims (7)

A paper storage section for storing a plurality of paper sheets;
A post-processing mechanism for performing post-processing on a plurality of sheets stored in the sheet storage unit;
A sheet discharge means for discharging a plurality of sheets after the post-processing from the sheet storage unit;
A paper discharge tray for stacking a plurality of sheets discharged from the paper storage section;
The plurality of sheets stored in the sheet storage unit are aligned in the sheet conveying direction, and the plurality of sheets stacked on the paper discharge tray are aligned in the sheet width direction perpendicular to the sheet conveying direction. Alignment means to perform,
A post-processing apparatus comprising: The aligning means includes an aligning member that contacts and separates from the sheet end surface, aligns the sheet, an aligning member holding shaft that rotatably holds the aligning member, and the aligning member in the rotation direction about the aligning member holding shaft. Alignment member rotation drive means for reciprocating movement, and alignment member sliding drive means for reciprocating the alignment member in the paper width direction,
The alignment member includes a sheet side end alignment surface formed as a surface perpendicular to the alignment member holding shaft, and a sheet front end alignment portion formed at a side edge of the sheet side end alignment surface, and By the driving of the alignment member sliding drive means, the sheet side end alignment surface is brought into contact with and separated from the sheet side end portions of the plurality of sheets stacked on the sheet discharge tray, and the sheets are aligned in the sheet width direction. 2. The sheet leading edge aligning section is brought into contact with and separated from the sheet leading edges of a plurality of sheets stored in the sheet storing section by driving the aligning member rotation driving means to align the sheets in the sheet conveying direction. The after-treatment device described in   The reciprocating motion of the aligning member in the rotation direction by the aligning member rotation driving means is performed by changing the angle within the operation range according to the size of the sheet stored in the sheet storing unit in the sheet transport direction. The post-processing apparatus according to claim 2, wherein The paper storage unit includes a paper rear end receiving member that receives a rear end of a paper to be stored in a paper transport direction and is movable in the paper transport direction.
4. The post-processing according to claim 1, wherein the sheet trailing edge receiving member is moved according to a size of the sheet stored in the sheet storage unit in a sheet conveyance direction. 5. apparatus.   The paper leading edge alignment portion of the alignment member corresponds to a paper leading edge position that changes according to the size of the paper stored in the paper storage portion in the paper transport direction, and is in contact with the paper in the contact portion that contacts the paper leading edge. The post-processing apparatus according to any one of claims 2 to 4, wherein the post-processing apparatus is formed as a curved surface or a polygonal surface having an angle of substantially a right angle. The paper discharge means has a pair of paper discharge rollers for discharging paper to the paper discharge tray,
6. The discharge roller pair changes a roller interval of the discharge roller pair according to the thickness or the number of sheets of a plurality of sheets stored in the sheet storage unit. The post-processing apparatus according to item 1.   An image forming apparatus that forms an image on a sheet, and a post-processing apparatus according to claim 1 that performs post-processing on a sheet on which an image has been formed by the image forming apparatus. An image forming system comprising:

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