JP2013071189A - Sheet punching device, sheet processing device, and image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sheet punching device capable of forming beautiful holes without any torn burr even if the number of sheets forming a booklet is increased.SOLUTION: The sheet punching device forms holes by a punch blade 640 having a blade of a shape in which ridges 640a and valleys 640b are alternately formed in the circumferential direction, and a punch die 631 having a die hole 647 for receiving the punch blade 640. The punch blade 640 is turned in the circumferential direction so that the valleys 640b of the punch blade 640 are not orthogonal to a sheet fiber orientation according to the fiber orientation along the sheet fiber orientation direction.

Description

  The present invention relates to a sheet punching apparatus that punches a sheet, a sheet processing apparatus including the punching apparatus, and an image forming apparatus.

  2. Description of the Related Art Conventionally, there has been known a punching device that punches holes suitable for filing in a sheet bundle (hereinafter referred to as a booklet) composed of a plurality of sheets that are saddle-stitched at the center in the sheet conveyance direction and folded in two at the binding portion. Yes. For example, a sheet processing apparatus is known in which a saddle stitching device and a punching device are arranged, and a booklet in which a plurality of sheets are saddle stitched by the saddle stitching device is conveyed to the punching device and sequentially punched. In the punching device, a punch blade having a peak portion and a valley portion and a punch die having a hole engaging with the punch blade are disposed to face each other. The punch blade is moved in the punch die direction with respect to the booklet positioned between them, and the punch blade penetrating the booklet is engaged with the hole of the punch die to form a hole in the booklet (Patent Document). 1).

  Incidentally, a sheet generally used in a copying machine, a printer, or the like is a so-called cut sheet. This cut sheet can be a so-called gap in the sheet manufacturing process along the orientation direction of the fibers of the sheet. Then, when cutting at the valley of the punch blade so as to cut off the gap, the fiber of the sheet is peeled off, and burrs appear as if the cut surface is torn, but cut at the valley of the punch blade along the gap It is known that a clean cut surface without burrs can be obtained. This is because the peak portion of the punch blade has a sharp shape to improve the cutting into the sheet, whereas the largest load is applied when the sheet is cut by the valley portion.

JP 2008-207267 A

  Therefore, if the sheet is cut in a state in which the perforations of the sheet forming the booklet are perpendicular to the valleys of the punch blades, the fibers of the sheet are cut at the valleys instead of the peaks of the punch blades. For this reason, the fibers of the sheet are peeled off, and burrs appear as if the holes were torn off. When the number of sheets forming the booklet increases, this phenomenon becomes remarkable and there is a problem that the quality is lowered.

  An object of the present invention is to provide a sheet punching device capable of forming clean holes without burrs that are torn even if the number of sheets forming a booklet increases.

  In order to achieve the above object, the present invention has a blade having a shape in which the crests and the troughs are alternately provided in the circumferential direction of the shaft so that the crests and troughs face each other. A punch blade provided to be rotatable in the circumferential direction of the shaft and movable in the axial direction, and a receiving hole for receiving the punch blade, and opposed to the punch blade in the movement direction of the punch blade. A punch die provided to move the punch blade in the moving direction in order to allow the punch blade to enter the receiving hole of the punch die, and a punch rotation driving means for rotating the punch blade in the circumferential direction. And the valleys of the punch blades are not perpendicular to the slits of the sheet according to the stitches along the fiber orientation direction of the sheet to be perforated by the punch blade and the punch die. Said punch blade, characterized in that and a control means for controlling the punch rotary drive means to rotate in a circumferential direction of said axis.

  ADVANTAGE OF THE INVENTION According to this invention, even if the number of sheets which make a booklet increases, the sheet | seat punching device which can open the beautiful hole without the burr | flash which was torn off can be provided.

Cross section of a copying machine Finisher cross section (A) is a perspective view showing a booklet before punching, (b) is a perspective view showing a booklet after punching. The figure which shows the perforated part in the finisher The figure which shows the punch blade and punch die in the punching section (A) (b) is a figure which shows the relationship between the trough part of a punch blade, and the clearance gap of a sheet | seat, (c) is a figure which shows the operation part which operates rotation of a punch blade. Block diagram of the entire copying machine Block diagram of perforated part The flowchart which shows the flow of operation | movement when saddle stitch punching mode is selected.

  Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the drawings. However, the dimensions, materials, shapes, and relative arrangements of the components described in the following embodiments should be appropriately changed according to the configuration of the apparatus to which the present invention is applied and various conditions. Therefore, unless specifically stated otherwise, the scope of the present invention is not intended to be limited thereto.

  FIG. 1 is a cross-sectional view showing an internal structure of a copying apparatus 1000 as an image forming apparatus to which a sheet processing apparatus can be attached. The principal part of the sheet processing apparatus is shown in FIG.

  As shown in FIGS. 1 and 2, the copying apparatus 1000 includes a document feeding unit 100, an image reader unit 200 and a printer unit 300, a folding processing unit 400, a finisher 500, a saddle stitch bookbinding unit 800, a punching unit 600, and an inserter 900. Etc. The folding processing unit 400, the saddle stitch binding unit 800, the punching unit 600, the inserter 900, and the like can be provided as options.

  As shown in FIG. 1, a document is set on the tray 100a of the document feeder 100 in an upright state as viewed from the user and in a face-up state (the surface on which the image is formed is upward). It is assumed that the binding position of the document is located at the left end portion of the document. The documents D set on the tray 100a are conveyed by the document feeder 100 one by one from the first page in the left direction (the arrow direction in the figure), that is, with the binding position as the leading edge. Further, the document is further conveyed from the left direction to the right direction on the platen glass 102 through a curved path, and then discharged onto the discharge tray 112. At this time, the scanner unit 104 is held in a predetermined position, and a document reading process is performed when the document passes through the scanner unit 104 from left to right. The above-described reading method is assumed to be document scanning. When the document passes over the platen glass 102, the document is irradiated by the lamp 103 of the scanner unit 104, and reflected light from the document is guided to the image sensor 109 via the mirrors 105, 106, 107 and the lens 108. .

  It is also possible to perform document reading processing by temporarily stopping the document conveyed by the document feeder 100 on the platen glass 102 and moving the scanner unit 104 from left to right in this state. This reading method is referred to as fixed document reading. When reading a document without using the document feeding unit 100, the user lifts the document feeding unit 100 and sets the document on the platen glass 102. In this case, the above-described original fixed reading is performed.

  The document image data read by the image sensor 109 is subjected to predetermined image processing and sent to the exposure control unit 110. The exposure control unit 110 outputs laser light corresponding to the image signal. The laser light is irradiated onto the photosensitive drum 111 while being scanned by the polygon mirror 110a. An electrostatic latent image corresponding to the scanned laser beam is formed on the photosensitive drum 111.

  The electrostatic latent image formed on the photosensitive drum 111 is developed by a developing unit 113 that constitutes an image forming unit together with the photosensitive drum 111, and is visualized as a toner image. On the other hand, the sheet S is conveyed to the transfer unit 116 from any of the cassettes 114 and 115, the manual feeding unit 125, and the double-sided conveyance path 124. The visualized toner image is transferred to the sheet in the transfer unit 116. The sheet after the transfer is subjected to a fixing process by a fixing unit 177.

  Then, the sheet that has passed through the fixing unit 177 is once guided to the path 122 by the switching member 121, and after the trailing edge of the sheet has passed through the switching member 121, the sheet is switched back and conveyed to the discharge roller 118 by the switching member 121. Then, the sheet is discharged from the printer unit 300 by the discharge roller 118. As a result, the surface on which the toner image is formed can be discharged from the printer unit 300 in a downward state (face down). This is called reverse discharge.

  As described above, by discharging the sheets to the outside in the face-down manner, when performing the image forming process in order from the first page, the page order can be made uniform. The case where the image forming process is performed in order from the first page is, for example, the case where the image forming process is performed using the document feeding unit 100 or the case where the image forming process is performed on the image data from the computer.

  When image forming processing is performed on both sides of the sheet, the sheet is guided straight from the fixing unit 177 toward the discharge roller 118, and the sheet is switched back immediately after the trailing edge of the sheet passes through the switching member 121. 121 leads to a double-sided conveyance path.

  Next, configurations of the folding processing unit 400 and the finisher (sheet processing apparatus) 500 will be described with reference to FIGS. 1 and 2.

  The folding processing unit 400 includes a conveyance path 131 for introducing the sheet discharged from the printer unit 300 and guiding the sheet to the finisher 500 side as a sheet processing apparatus. On the conveyance path 131, conveyance roller pairs 130 and 133 are provided. The switching member 135 provided in the vicinity of the conveyance roller pair 133 is for guiding the sheet conveyed by the conveyance roller pair 130 to the folding path 136 or the finisher 500 side.

  When the sheet folding process is performed, the switching member 135 is switched to the folding path 136 and the sheet is guided to the folding path 136. The sheet guided to the folding path 136 is conveyed to the folding roller 140 and folded into a Z shape. On the other hand, when the folding process is not performed, the switching member 135 is switched to the finisher 500 side, and the sheet discharged from the printer unit 300 is directly fed through the conveyance path 131.

  The sheet conveyed through the folding path 136 is folded by the folding rollers 140 and 141 in a loop formed by abutting the leading end against the stopper 137. By further folding the loop formed by abutting the bent portion against the upper stopper 143 by the folding rollers 141 and 142, the sheet is Z-folded. The Z-folded sheet is sent to the conveyance path 131 via the conveyance path 145 and is discharged to the finisher 500 attached downstream by the conveyance roller pair 133. The folding processing operation by the folding processing unit 400 is selectively performed.

  The finisher 500 takes in a sheet from the printer unit 300 conveyed via the folding processing unit 400. The finisher 500 aligns a plurality of captured sheets and bundles them as one sheet bundle, stapling processing (binding processing) for stapling the rear end side of the sheet bundle, sorting processing, non-sorting processing, and other sheet processing. Is to do.

  As shown in FIG. 2, the finisher 500 has a conveyance path 520 for taking the sheet conveyed via the folding processing unit 400 into the apparatus, and the conveyance path 520 is provided with a plurality of conveyance roller pairs. Yes.

  A switching member 513 provided at the end of the transport path 520 switches the path between an upper discharge path 521 and a lower discharge path 522 connected downstream. The upper discharge path 521 discharges to the upper stack tray 592. On the other hand, the lower discharge path 522 discharges to the processing tray 550. The sheets discharged to the processing tray 550 are accommodated in a bundle while being sequentially aligned, and sorting and stapling are performed according to settings from the operation unit 1 (see FIG. 7). Thereafter, the sheet bundle is discharged to the stack trays 591 and 592 by the bundle discharge roller pair 551.

  Note that the above-described stapling process is performed by the stapler 560, and the stapler 560 can be moved in the width direction orthogonal to the sheet conveyance direction, and can be stapled at an arbitrary position on the sheet. The stack trays 591 and 592 are configured to be movable in the vertical direction (sheet stacking direction). The upper stack tray 592 can receive sheets from the upper discharge path 521 and the processing tray 550. Further, the lower stack tray 591 can receive sheets from the processing tray 550. In this way, a large number of sheets can be stacked on the stack trays 591 and 592, and the stacked sheets are regulated and aligned by the rear end guide 593 extending in the vertical direction at the rear end.

  Next, the configuration of the saddle stitch bookbinding unit 800 will be described.

  The sheet switched to the right side by the switching member 514 provided in the middle of the lower discharge path 522 passes through the saddle discharge path 523 and is sent to the saddle stitch bookbinding portion 800. The sheet is delivered to the saddle entrance roller pair 801, the entrance is selected by a switching member 802 operated by a solenoid according to the size, and is carried into the storage guide 803 of the saddle stitch bookbinding portion 800. The loaded sheet is conveyed by the sliding roller 804 until the leading end comes into contact with the movable sheet positioning member 805. The saddle entrance roller pair 801 and the sliding roller 804 are driven by a motor M1. In addition, a stapler 820 is provided in the middle of the storage guide 803 so as to face the storage guide 803. The stapler 820 is divided into a driver 820a that projects a needle and an anvil 820b that bends the projected needle. The sheet positioning member 805 stops at a position where the central portion in the sheet conveying direction is the binding position of the stapler 820 when the sheet is carried in. The sheet positioning member 805 is movable under the driving of the motor M2, and changes its position according to the sheet size.

  A pair of folding rollers 810a and 810b is provided on the downstream side of the stapler 820, and a protruding member 830 that constitutes sheet processing means together with the pair of folding rollers 810a and 810b is provided at a position opposite to the pair of folding rollers 810a and 810b. It has been. The protruding member 830 has a position retracted from the storage guide 803 as a home position. By driving the motor M3, the protruding member 830 pushes the sheet bundle stored in the storage guide 803 into the nip of the pair of folding rollers 810a and 810b, and folds the sheet bundle while conveying the sheet bundle by the pair of folding rollers 810a and 810b. Thereafter, the protruding member 830 returns to the home position again. Note that a pressure F1 sufficient to crease the bundle is applied between the folding roller pair 810 by a spring (not shown). The creased bundle is discharged toward the punching unit 600 via the first fold conveying roller pair 811a and 811b and the second fold conveying roller pair 812a and 812b. Sufficient pressures F2 and F3 are applied to the first fold conveyance roller pair 811 and the second fold conveyance roller pair 812 to convey and stop the folded bundle.

  The folding roller pair 810, the first fold conveying roller pair 811 and the second fold conveying roller pair 812 are rotated at the same speed by the same motor M4.

  When the sheet bundle bound by the stapler 820 is folded, the sheet positioning member 805 is moved away from the position at the time of the stapling process so that the stapling position of the sheet bundle comes to the nip position of the pair of folding rollers 810 after the stapling process is completed. Descent a predetermined distance. Accordingly, the sheet bundle can be folded around the position where the stapling process is performed.

  The aligning plate pair 815 is a pair of aligning plates that has a surface protruding to the storage guide 803 around the outer peripheral surface of the pair of folding rollers 810a and 810b and aligns the sheets stored in the storage guide 803. The alignment plate pair 815 is positioned in the width direction of the sheet by moving in the sandwiching direction with respect to the sheet under the driving of the motor M5.

  The booklet shown in FIG. 3A is formed by the saddle stitch bookbinding portion 800 having such a configuration.

  The saddle stitch bookbinding portion 800 having such a configuration forms a folded sheet bundle (folded sheet bundle; hereinafter referred to as a booklet) S. Note that the booklet is not limited to this, and includes a booklet that is folded in two without performing the binding process. Further, it includes a single sheet that is folded in half.

  Next, a punching unit 600 as a sheet punching device will be described. The punching portion 600 is located downstream of the saddle stitch binding portion 800 (left side in the figure).

  FIG. 4 is an enlarged view of the perforated portion 600 of FIG. In the figure, reference numeral 610 denotes a booklet receiving unit having a lower conveying belt 611 extending in the conveying direction only on the lower side for receiving and conveying the booklet from the saddle stitch bookbinding unit 800. At the time of booklet delivery, the lower conveyor belt 611 rotates in the conveyance direction, so that even if the booklet falls from the second conveyance roller pair 812, the bundle is not rotated but can be received in the conveyed posture. it can.

  A pair of side guides 612 is disposed on the outer side of the lower conveyance belt 611, and by operating these in the width direction of the booklet, the width direction position of the booklet can be corrected. In addition, a presser guide 614 that prevents the booklet from opening is formed on the upper side of the pair of side guides 612, which functions as a guide for smoothly delivering the booklet to the downstream portion. Further, conveyance claws 613 that move in parallel with the lower conveyance belt 611 are disposed on both sides of the lower conveyance belt 611. The conveyance claw 613 moves forward and backward at substantially the same speed as the lower conveyance belt 611. When a slip occurs between the lower conveyance belt 611 and the booklet, the conveyance claws 613 come into contact with the booklet rear end and reliably push the booklet rear end downstream. The lower transport belt 611, the side guide pair 612, and the transport claws 613 operate by being driven by motors SM1, SM2, and SM3, respectively.

  Reference numeral 620 denotes an entrance conveyance unit which includes a lower conveyance belt 621 and an upper conveyance belt 622 for receiving a booklet from the booklet receiving unit 610 and conveying it downstream. The upper conveyor belt 622 can be rotated around the fulcrum 623 depending on the thickness of the booklet, and is pressed against the lower conveyor belt 621 by a spring (not shown). The vertical conveyor belts 621 and 622 are driven by a motor SM4. A booklet receiving entrance detection sensor 615 receives a booklet from the saddle stitch bookbinding unit 800 and detects that a booklet is present on the lower conveyance belt 611. Reference numeral 616 denotes a booklet receiving exit detection sensor which serves as an input signal for operating the side guide pair 612 and the conveyance claw 613 by detecting the booklet.

  Reference numeral 625 denotes a punching processing unit which includes a punching unit 630 for making a hole in a booklet and a positioning unit 650 for positioning a booklet folding top and determining a punching position in the booklet transport direction.

  FIG. 5 is a view of the punching unit 630 as viewed from the downstream side of the booklet conveyance. The punching unit 630 is divided into a punch die 631 that is fixed to the frame so as to face the upper unit that moves up and down. The upper unit has a strong pressing base 632 that moves up and down via links 636, 637, and 638 when driven by a motor SM5 as a punch driving means, and an upper presser plate 633 that is connected by a slide connecting member 634. doing. A compression spring 635 is disposed on the outer periphery of the slide connecting member 634. The upper presser plate 633 is movable in the contact / separation direction with respect to the punch die 631 by a linear motion guide 646. When the presser base 632 is in the upper position, the punch die 631 and the upper presser plate 633 are separated from each other, and the booklet is conveyed therebetween. When the presser base 632 is in the lower position, the booklet is firmly pressed and held by the punch die 631 and the upper presser plate 633 by the compression spring 635 that expands and contracts according to the thickness of the booklet. The punch blade 640 is provided in the presser base 632, and the booklet is punched in cooperation with a die hole (receiving hole) 647 provided in the punch die 631 as the presser base 632 is lowered. A booklet S with holes P is shown in FIG. The perforated waste passes through the die hole 647 and is discharged to the waste box 648 (see FIG. 4). Reference numeral 639 denotes a top dead center detection sensor which detects that the presser base 632 is in the upper position.

  The punch blade 640 has a blade having a shape in which crests and troughs are alternately provided in the circumferential direction of the cylindrical shaft so that crests and troughs face each other, and drills with a small drilling force. It is possible. Here, as shown in FIGS. 6 (a) and 6 (b), the punch blade 640 has two ridges 640a facing each other in the circumferential direction of the cylindrical shaft so as to form a round hole, and between the ridges 640a. Two trough portions 640b are provided at the tip portion so as to face each other. The punch blade 640 is provided so as to be rotatable in the circumferential direction and is movable in a moving direction (axial direction) orthogonal to the circumferential direction.

  The punch blade 640 is moved in the moving direction in response to driving of a motor SM5 as punch driving means in order to cause the punch blade 640 to enter the die hole 647 of the punch die 631. The punch blade 640 is driven by a motor SM7 (SM8) as a punch rotation driving means by a gear 641 provided to the motor SM7 (SM8) and a gear 642 provided on the motor SM7 (SM8). It is held rotatably in the circumferential direction.

  As shown in FIGS. 6A and 6B, the punch blade 640 is advantageous for perforation because of the slits along the fiber orientation direction of the sheet and the shape of the blades 640a and valleys 640b of the punch blade 640. It can be changed to the direction. Specifically, the punch blades 640 are rotated in the circumferential direction so that the valleys 640b of the punch blades 640 are not perpendicular to the slits of the sheet according to the slits along the direction of fiber orientation of the sheet. The initial position of the punch blade 640 is detected by a home position sensor (not shown), and is controlled by a control means to be described later based on the amount of rotation from the home position.

  Three examples will be given as methods for changing the direction of the punch blade 640.

  The first example is a method of using the punching operation unit (input means) 602 attached to the exterior of the punching unit 600 of FIG. In recent years, paper makers have come to describe information about the direction of the gap when manufacturing cut sheets in a package for packing the cut sheets. As shown in FIGS. 6 (a) and 6 (b), the user adjusts the sheet marks (in the direction of the arrow) based on the described information, and as shown in FIG. The operation button 605 or 606 is pressed so as to match the direction indication mark 603 or 604. The direction of the punch blade can be determined by turning on the LED 607 or 608. Based on the input information of the punching operation unit 602, a punching control unit 601 (see FIG. 7) as control means drives the motor SM7 (SM8) to control the direction of the punch blade.

  As in the first example, the second example is an example in which the direction of the sheet gap is input from the operation unit (input unit) 1 of the copying apparatus 1000 based on information described in the package. The operation unit 1 can specify the sheet size, paper type, and stitch direction of the feeding cassettes 114 and 115 and the manual feeding unit 125. Based on the input information of the operation unit 1, the CPU circuit unit 150 (see FIG. 7) of the copying apparatus 1000 issues a command, which is transmitted to the punching control unit 601 via the finisher control unit 501. Then, the punching control unit 601 drives the motor SM7 (SM8) to control the direction of the punch blade.

  A third example is a method of controlling the direction of the punch blade based on information from a gap detection sensor (skim detection means) 580 provided in the finisher 500 of FIG. A sensor using a terahertz wave as disclosed in “Japanese Patent Application Laid-Open No. 2008-174383” is known as the gap detection sensor 580. Based on the detection information of the gap detection sensor 580, the CPU circuit unit 150 of the copying apparatus 1000 issues a command, which is transmitted to the punching control unit 601 via the finisher control unit 501. Then, the punching control unit 601 drives the motor SM7 (SM8) to control the direction of the punch blade. In addition, the sheet gap is limited to two vertical / horizontal orthogonal directions from the cut sheet manufacturing process and the cutting process, but the fiber orientation direction is not 100% aligned. Determines the intensity of the transmitted or reflected electromagnetic wave with a certain width.

  The positioning unit 650 in FIG. 4 is a unit for positioning the booklet in the transport direction and determining the punching position. By driving the motor SM6, the positioning plate 651 rises in the direction of the arrow in the drawing via the links 653, 654, and 655, and the booklet conveyance path formed by the punch die 631 and the upper presser plate 633 is closed. Positioning in the width direction orthogonal to the booklet transport direction is performed by the alignment operation of the side guide pair 612 described above, and the transported booklet abuts against the positioning plate 651 to perform positioning in the transport direction. After the punching, the positioning plate 651 is lowered, so that the booklet can be conveyed.

  Reference numeral 660 in FIG. 4 denotes an exit conveyance unit, which includes a lower conveyance belt 661 and an upper conveyance belt 662 for receiving a perforated booklet and conveying it downstream. The upper conveyor belt 662 can be rotated around the fulcrum 663 according to the thickness of the booklet, and is pressed against the lower conveyor belt 661 by a spring (not shown). The upper and lower transport belts 661 and 662 are drivingly connected to the inlet transport unit 620 and are driven by the motor SM4.

  Reference numeral 670 denotes a conveyor tray on which the booklet discharged from the exit conveyance unit 660 is stacked. On the lower surface of the conveyor tray 670, there is provided a conveyor belt 671 that moves in the conveying direction under the drive of the motor SM10, and repeats a predetermined amount of movement each time a booklet is ejected to stack the booklet. The discharge detection sensor 664 detects that the booklet has been discharged from the exit conveyance unit 660.

  The inserter 900 of FIG. 2 is for feeding sheets set on the insert trays 901 and 902 by the user to one of the stack trays 700 and 701 and the conveyor tray 670 without passing through the printer unit 300. . The sheet bundles stacked on the insert trays 901 and 902 are sequentially separated one by one and joined to the transport path 520 of the finisher 500 at a desired timing.

  FIG. 7 is a block diagram of the copying apparatus 1000. The CPU circuit unit 150 has a CPU (not shown), and according to the control program stored in the ROM 151 and the setting of the operation unit 1, the document feeding control unit 101, the image reader control unit 201, the image signal control unit 202, and the printer The controller 301 and the external I / F 203 are controlled. Further, the folding processing control unit 401 and the finisher control unit 501 are controlled through communication with the mounted sheet processing apparatus. The document feeding control unit 101 controls the document feeding unit 100, the image reader control unit 201 controls the image reader unit 200, and the printer control unit 301 controls the printer unit 300. The folding processing control unit 401 controls the folding processing unit 400, and the finisher control unit 501 controls the finisher 500, the saddle stitch binding unit 800, and the inserter 900. A punching control unit (control unit) 601 controls the punching unit (sheet punching device) 600 based on a command from the finisher control unit 501.

  The operation unit 1 includes a plurality of keys for setting various functions relating to image formation, a display unit for displaying a setting state, and the like. The operation unit 1 outputs a key signal corresponding to each key operation by the user to the CPU circuit unit 150 and displays corresponding information on the display unit based on the signal from the CPU circuit unit 150.

  The RAM 152 is used as an area for temporarily storing control data and a work area for operations associated with control. An external I / F 203 is an interface between the copying apparatus 1000 and an external computer 204, develops print data from the computer 204 into a bitmap image, and outputs it to the image signal control unit 202 as image data. Further, an image of a document read by an image sensor (not shown) is output from the image reader control unit 201 to the image signal control unit 202. The printer control unit 301 outputs the image data from the image signal control unit 202 to the exposure control unit 110 (see FIG. 1).

  FIG. 8 is a block diagram of the drilling control unit 601. The drilling control unit 601 controls each drive motor SM1, SM2, SM3, SM4, SM5, SM6, SM7, SM8, SM10.

  Next, based on the above configuration, the operation of each part will be described together with the flow of the booklet regarding the punching operation in the punching unit 600 as the sheet punching device.

  FIG. 9 is a flowchart showing an operation flow when the saddle stitch punching mode is selected in the finisher 500 having the stitch detection sensor 580.

  When the saddle stitch punching mode is selected in the operation unit 1, the punching unit 600 performs an initial operation as shown in FIG. 9 (STEP 1). When the sheet passes through the gap detection sensor 580, the gap direction (the fiber orientation direction of the sheet) is detected, and the finisher control unit 501 outputs the gap information to the perforation control unit 601 (STEP 2). The punching control unit 601 drives the punch blade rotation motors SM7 and SM8 based on the received gap information and determines the direction of the punch blade 640 (STEP 3). As a result, the valley 640b of the punch blade 640 is directed in a direction that is not orthogonal to the slits of the sheet forming the booklet, and the fiber of the sheet is cut by the peak 640a without being cut by the valley 640b of the punch blade 640. Will be. For this reason, the hole does not burr as if it was torn off, and the quality is improved.

  While the booklet is created by the saddle stitch bookbinding unit 800, the side guide pairs 612 disposed on both sides of the conveyance path of the booklet receiving unit 610 move to the standby position according to the booklet size, and the positioning plate 651 is positioned. Move to position (STEP 4). When the punching control unit 601 receives a booklet discharge notification from the saddle stitch bookbinding unit 800 (STEP 5), the lower conveyance belt 611 is rotated by the drive motor SM1 (STEP 6), and the booklet is conveyed. Further, after the booklet is detected by the booklet reception inlet detection sensor 615 and the booklet reception outlet detection sensor 616 (STEP 7 and 8), the conveyance of the booklet is temporarily stopped (STEP 9).

  Thereafter, the side guide pair 612 is moved in the booklet width direction by the drive motor SM2 to perform the alignment operation (STEP 10). Thereafter, the entrance motor 620 and the outlet transport unit 660 are driven by the drive motor SM4 (STEP 11), and the transport of the booklet is resumed by the transport claw 613 and the lower transport belt 611 disposed upstream of the booklet receiver 610. (STEP 12). The conveyance claw 613 is driven by a drive motor SM3.

  When the booklet receiving exit detection sensor 616 detects the discharge of the booklet (STEP 13), the transport claw 613 retreats upstream in the transport direction (STEP 14). When the booklet conveyed by the inlet conveyance unit 620 is detected by the booklet positioning detection sensor 626 and abuts against the positioning plate 651 (STEP 15), the driving of the inlet conveyance unit 620 stops (STEP 16).

  Then, the pressing base 632 is moved to the lower position by the drive motor SM5 (STEP 17), and the booklet is punched by the punch blade 640 and the die hole 647. Next, the pressing base 632 moves to the upper position (STEP 18), and the punch die 631 and the upper pressing plate 633 are separated from each other. Then, the exit transport unit 660 is driven by the drive motor SM4 (STEP 19), the booklet transported by the exit transport unit 660 is discharged to the conveyor tray 670, and the discharge detection sensor 664 detects the completion of discharge (STEP 20). When discharge completion is detected by the discharge detection sensor 664, the exit conveyance unit 660 stops driving (STEP 21). The booklets discharged to the conveyor tray 670 are sequentially stacked in a straw shape. If the discharged booklet is not the final booklet, the process returns to STEP 4, and if it is the final booklet, the job is ended (STEPs 22 and 23).

  As described above, according to the present embodiment, by rotating the punch blade in the circumferential direction around the punch axis and changing the direction of the blade having the shape of the crest and trough, The trough 640b is oriented in a direction that is not orthogonal to the stitches of the sheet forming the booklet. That is, the fiber of the sheet is not cut at the peak portion 640a of the punch blade 640 and is not cut at the valley portion 640b. For this reason, even if the number of booklets increases, the holes made in the booklet do not have burrs as if they were torn off, and clean holes can be made, improving the quality.

  In the above-described embodiment, the copying apparatus is exemplified as the image forming apparatus, but the present invention is not limited to this. For example, the image forming apparatus may be another image forming apparatus such as a printer or a facsimile apparatus, or another image forming apparatus such as a multi-function machine that combines these functions. The same effect can be obtained by applying the present invention to a sheet punching device used in these image forming apparatuses, or a sheet punching device in a sheet processing apparatus connected to these image forming apparatuses.

  In the above-described embodiment, the sheet punching apparatus in the sheet processing apparatus that is detachable from the image forming apparatus is exemplified, but the present invention is not limited to this. For example, the image forming apparatus may be a sheet punching device that is integrally provided, and the same effect can be obtained by applying the present invention to the sheet punching device.

P ... hole S ... booklet 1 ... operation part 150 ... CPU circuit part 600 ... punching part 601 ... punching control part 602 ... punching operation part 610 ... booklet receiving part 620 ... inlet conveyance part 625 ... punching processing part 630 ... punching unit 631 ... Punch die 632 ... presser base 633 ... upper presser plate 640 ... punch blade 640a ... peak portion 640b ... trough portion 647 ... die hole 650 ... positioning unit 651 ... positioning plate 670 ... conveyor tray 800 ... saddle stitch bookbinding portion 1000 ... copying machine

Claims (6)

The crests and the troughs have blades with shapes provided alternately in the circumferential direction of the shaft so that the crests and troughs face each other, and are provided so as to be rotatable in the circumferential direction of the shaft. And a punch blade provided so as to be movable in the axial direction,
A punch die having a receiving hole for receiving the punch blade and provided facing the punch blade in the moving direction of the punch blade;
Punch driving means for moving the punch blade in the moving direction in order to allow the punch blade to enter the receiving hole of the punch die;
Punch rotation driving means for rotating the punch blade in the circumferential direction;
The punch blades are arranged on the shaft so that the valleys of the punch blades do not intersect perpendicularly with the slits of the sheet in accordance with the stitches along the fiber orientation direction of the sheet to be punched by the punch blade and the punch die. Control means for controlling the punch rotation drive means to rotate in the circumferential direction of
A sheet punching device comprising:   2. A gap detection unit that detects a gap in the sheet, wherein the control unit controls driving of the punch rotation driving unit based on detection information of the gap detection unit. The sheet punching device according to 1.   2. The input device according to claim 1, further comprising: an input unit configured to input the sheet gap as information, wherein the control unit controls driving of the punch rotation driving unit based on input information of the input unit. Sheet punching device.   4. A sheet processing unit that performs processing on a sheet, and a sheet punching device according to claim 1, wherein the sheet punching unit performs punching processing on a sheet processed by the sheet processing unit or a sheet bundle including a plurality of sheets. And a sheet processing apparatus.   The sheet processing apparatus according to claim 4, wherein the sheet processing unit is configured to fold a sheet or a plurality of sheets into two.   An image forming unit that forms an image on a sheet, and a sheet punching device according to any one of claims 1 to 3, which performs punching processing on a sheet on which an image is formed or a sheet bundle composed of a plurality of sheets. An image forming apparatus comprising:

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