JP2008037545A - Image forming system having post-processing device with cutting function - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve the problems that center folding of each of a bunch of sheets may cause sheet dislocation in the bunch during cutting with no saddle stitching in a book binding mode and cutting in the state of dislocation produces the sheet sizes to be different from each other. <P>SOLUTION: An image forming device which forms images on sheets and a sheet post-processing device which sequentially receives the sheets on which the images are formed by the image forming device each comprise a saddle stitching means for binding the centers of the sheets on which the images are formed, a center folding means for folding the centers of the sheets on which the images are formed, a cutting means for cutting the sheet ends of the bunch of sheets folded by the center folding means, and a setting means for setting post-processing including saddle stitching, center folding and cutting for the sheet post-processing device. A control means selects a first center folding mode in which the centers of the plurality of sheets are folded at the same time and a second center folding mode in which those are folded one by one, depending on a combination of the saddle stitching or not and the cutting or not set by the setting means. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a sheet processing apparatus having a cutting function used in an image forming apparatus such as a copying machine or a laser beam printer.

  2. Description of the Related Art Conventionally, in an image forming apparatus such as a copying machine, a system having a bookbinding mode for performing post-processing of saddle stitching processing for binding the central portion of a sheet and folding processing for folding the central portion of a sheet by connecting a post-processing device. Is provided.

As shown in FIG. 36, the bookbinding-processed sheet bundle has an end position opposite to the half-folded end when the number of sheets in the bundle is large or the thickness of each sheet in the bundle is thick. The outer paper and the outer paper are not aligned, and the appearance when finished is reduced. Therefore, the user desires not only a post-processing device with a cutting function (see, for example, Patent Document 1) or an irregular end portion that trims the irregular end portion by a few millimeters with a cutter or the like to align the end portion and improve the appearance. A post-processing device with a cutting function capable of cutting an arbitrary width (for example, see Patent Document 2) is provided.
JP 2003-3419192 A JP 2004-210509 A

  As in the conventional example (Patent Document 2), the post-processing apparatus having the bookbinding mode can perform the half-folding process in which the paper is folded in half at the center of the paper, and there is no post-processing apparatus having a dedicated folding function. A function of folding only a plurality of sheets of paper at a time at the center in half can be realized by performing only the middle folding process without performing the saddle stitching process. Further, if the post-processing apparatus has a cutting function, the end of the half-folded sheet can be cut and finished to an arbitrary size desired by the user.

  A bundle of sheets that has been bound is fixed with a staple in which a plurality of sheets are bound, and is transported as a unit when transported. Therefore, there is a deviation in the transport direction between the outer sheet and the inner sheet of the bundle. There is nothing.

  However, when transporting a plurality of sheet bundles that have not been bound, each sheet is not fixed with a needle, and the outer sheet and the inner sheet of the sheet bundle that are in contact with a driving member such as a roller pair There is a difference in the transport force that is received. While being pinched by the roller pair, the inner side paper having a weaker conveying force may be shifted upstream in the conveying direction. In particular, as shown in FIG. 34, when a member is pushed out toward the nip position of the roller pair and a plurality of sheets are folded at the same time, the roller and the outer sheet are placed before the sheet is folded into the nip of the roller pair. Since they are in contact with each other, the outer side of the sheet is already subjected to the conveyance force downstream in the conveyance direction before being folded between the pair of rollers, so that a deviation occurs between the outer and inner sheets of the sheet bundle.

  In this way, when the sheet bundle is misaligned and the edge of the sheet is not aligned without performing the saddle stitching process, the size of each sheet is slightly different. The paper cannot be finished to the size desired by the user every time. Provided is an image forming system capable of cutting and finishing to a size desired by a user with high accuracy.

  An object of the present invention is to solve the above problems, and in order to achieve the above object, in the present invention, an image forming apparatus that forms an image on a sheet and a sheet that sequentially receives sheets formed with the image forming apparatus. In a processing apparatus, saddle stitching means for binding the center of an image-formed sheet, center folding means for folding the center of an image-formed sheet, cutting means for cutting a sheet end portion of a sheet bundle folded by the middle folding means, and sheet A setting unit for setting post-processing such as saddle stitching, half-folding, and cutting in the post-processing apparatus is provided. Depending on the combination of whether or not to perform saddle stitching set by the setting unit, Control means for switching between a first half-folding mode in which the sheets are folded at the same time and a second half-folding mode in which the sheets are folded in each sheet is provided.

  Further, when the setting unit is set to perform cutting without saddle stitching, the second half-folding mode is selected, and the sheet is folded and cut for each sheet, and is not set without performing saddle stitching. In this case, the first half-fold mode is selected, and a plurality of sheets are folded and cut simultaneously.

  As described above, in the present invention, when performing edge cutting on a sheet that has been folded without performing saddle stitching, by cutting a plurality of sheets one by one without cutting simultaneously, Each sheet can be cut with high accuracy, and all sheets can be finished to a size desired by the user.

  Embodiments of the present invention will be described below with reference to the drawings.

(overall structure)
FIG. 1 is a longitudinal sectional view showing a main part configuration of an embodiment of an image forming apparatus of the present invention.

  As shown in FIG. 1, the image forming apparatus includes an image forming apparatus main body 10, a finisher 500, and a trimmer 900. The image forming apparatus main body 10 includes an image reader 200 and a printer 300 that read a document image.

  A document feeder 100 is mounted on the image reader 200. The document feeder 100 feeds documents set upward on the document tray one sheet at a time in order from the first page, and flows on the platen glass 102 from the left through a curved path, passing through a reading position. The paper is conveyed to the right and then discharged toward the external paper discharge tray 112. When the original passes through the sink reading position on the platen glass 102 from left to right, the original image is read by the scanner unit 104 held at a position corresponding to the sink reading position. This reading method is generally referred to as document scanning. Specifically, when the original passes through the reading position, the original reading surface is irradiated with light from the lamp 103 of the scanner unit 104, and the reflected light from the original passes through the mirrors 105, 106, and 107 to the lens. To 108. The light that has passed through the lens 108 forms an image on the imaging surface of the image sensor 109.

  By transporting the document so that it passes through the flow reading position from the left to the right in this way, the document reading scan in which the direction perpendicular to the document transport direction is the main scanning direction and the transport direction is the sub-scanning direction is performed. Done. That is, the entire original image is read by conveying the original in the sub-scanning direction while the original image is read by the image sensor 109 line by line in the main scanning direction when the original passes the reading position. The read image is converted into image data by the image sensor 109 and output. Image data output from the image sensor 109 is input as a video signal to the exposure control unit 110 of the printer 300 after predetermined processing is performed in an image signal control unit 202 described later.

  It is also possible to read the document by transporting the document onto the platen glass 102 by the document feeder 100 and stopping it at a predetermined position, and scanning the scanner unit 104 from left to right in this state. This reading method is a so-called fixed document reading method.

  When reading a document without using the document feeder 100, the user first lifts the document feeder 100 to place the document on the platen glass 102, and then scans the scanner unit 104 from left to right. The original is read by. That is, when reading a document without using the document feeder 100, a fixed document reading is performed.

  The exposure control unit 110 of the printer 300 modulates and outputs a laser beam based on the input video signal, and the laser beam 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. Here, as will be described later, the exposure control unit 110 outputs a laser beam so that a correct image (an image that is not a mirror image) is formed during document fixed reading.

  The electrostatic latent image on the photosensitive drum 111 is visualized as a developer image by the developer supplied from the developing device 113. In addition, at the timing synchronized with the start of laser light irradiation, paper is fed from each of the cassettes 114 and 115, the manual paper feeding unit 125 or the double-sided conveyance path 124, and this paper is placed between the photosensitive drum 111 and the transfer unit 116. To be transported. The developer image formed on the photosensitive drum 111 is transferred onto the paper fed by the transfer unit 116.

  The sheet on which the developer image is transferred is conveyed to the fixing unit 117, and the fixing unit 117 fixes the developer image on the sheet by heat-pressing the sheet. The sheet that has passed through the fixing unit 117 is discharged from the printer 300 toward the outside (finisher 500) through the flapper 121 and the discharge roller 118.

  Here, when the sheet is discharged with its image forming surface facing downward (face-down), the sheet that has passed through the fixing unit 117 is once guided into the reverse path 122 by the switching operation of the flapper 121, and the trailing edge of the sheet. After passing through the flapper 121, the paper is switched back and discharged from the printer 300 by the discharge roller 118. Hereinafter, this form of paper discharge is referred to as reverse paper discharge. This reverse paper discharge is performed when forming an image sequentially from the first page, such as when forming an image read using the document feeder 100 or when forming an image output from a computer. The paper order after paper discharge is the correct page order.

  Further, when a hard sheet such as an OHP sheet is fed from the manual sheet feeding unit 125 and an image is formed on this sheet, the image forming surface is faced up without leading the sheet to the reverse path 122 (face-up). ) By the discharge roller 118.

  Further, when double-sided recording for image formation is set on both sides of the paper, the paper is guided to the reverse path 122 by the switching operation of the flapper 121 and then transported to the double-sided transport path 124 and then guided to the double-sided transport path 124. Control is performed so that the fed paper is fed again between the photosensitive drum 111 and the transfer unit 116 at the timing described above.

  The paper discharged from the printer 300 is sent to the finisher 500. The finisher 500 performs each process such as a binding process, and the trimmer 900 further performs a cutting process on the edge of the sheet on which the saddle stitching or the folding process is performed by the finisher 500.

(System block diagram)
Next, the configuration of a controller that controls the entire image forming apparatus will be described with reference to FIG. FIG. 2 is a block diagram showing a configuration of a controller that controls the entire image forming apparatus of FIG.

  As shown in FIG. 2, the controller includes a CPU circuit unit 150. The CPU circuit unit 150 includes a CPU (not shown), a ROM 151, and a RAM 152. Each block 101 is controlled by a control program stored in the ROM 151. , 201, 202, 209, 301, 401, 701 are collectively controlled. The RAM 152 temporarily stores control data and is used as a work area for arithmetic processing associated with control.

  The document feeder control unit 101 controls driving of the document feeder 100 based on an instruction from the CPU circuit unit 150. The image reader control unit 201 performs drive control on the above-described scanner unit 104, the image sensor 109, and the like, and transfers an analog image signal output from the image sensor 109 to the image signal control unit 202.

  The image signal control unit 202 converts each analog image signal from the image sensor 109 into a digital signal, performs each process, converts the digital signal into a video signal, and outputs the video signal to the printer control unit 301. In addition, the digital image signal input from the computer 210 via the external I / F 209 is subjected to various processes, and the digital image signal is converted into a video signal and output to the printer control unit 301. The processing operation by the image signal control unit 202 is controlled by the CPU circuit unit 150. The printer control unit 301 drives the above-described exposure control unit 110 based on the input video signal.

  The operation display device control unit 401 exchanges information between the operation display device 400 and the CPU circuit unit 150. The operation display device 400 includes a plurality of keys for setting various functions relating to image formation, a display unit for displaying information indicating a setting state, and the like, and a key signal corresponding to the operation of each key is sent to the CPU circuit unit 150. While outputting, corresponding information is displayed on the display unit based on the signal from the CPU circuit unit 150.

  The finisher control unit 501 is mounted on the finisher 500 and performs drive control of the entire finisher by exchanging information with the CPU circuit unit 150. This control content will be described later.

  A trimmer control unit 901 is mounted on the trimmer 900, exchanges information with the finisher control unit 501, and controls driving of the entire trimmer. This control will also be described later.

(Operation display device)
FIG. 27 is a diagram showing an operation display device 400 in the image forming apparatus of FIG.

  The operation display device 400 includes a start key 402 for starting an image forming operation, a stop key 403 for interrupting the image forming operation, ten keys 404 to 412 and 414 for setting numerical values, an ID key 413, and a clear key. 415, a reset key 416, a user mode key 417 for setting various devices, and the like are arranged. In addition, a liquid crystal display unit 420 having a touch panel formed thereon is arranged, and a soft key can be created on the screen.

  The image forming apparatus has various processing modes such as non-sorting, sorting, stapling sorting (binding mode), and bookbinding mode as post-processing modes. Such setting of the processing mode is performed by an input operation from the operation display device 400. For example, when setting the post-processing mode, when the “sorter” soft key is selected on the initial screen shown in FIG. 27, a menu selection screen is displayed on the display unit 420, and the processing mode is selected using this menu selection screen. Is set.

(Finisher)
Next, the configuration of the finisher 500 will be described with reference to FIG. FIG. 3 is a configuration diagram of the finisher 500 of FIG.

  The finisher 500 sequentially takes in the sheets ejected from the image forming apparatus 10, aligns a plurality of fetched sheets and bundles them into one bundle, staples the staple end of the bundle of bundled sheets, and takes in Each sheet post-processing such as punching, sorting, non-sorting, bookbinding and the like for punching holes in the vicinity of the trailing edge of the paper is performed.

  As shown in FIG. 3, the finisher 500 takes in the paper discharged from the image forming apparatus 10 into the interior by the entrance roller pair 502, and the paper taken in by the entrance roller pair 502 passes through the transport roller pair 503. It is sent toward the buffer roller 505. An entrance sensor 531 is provided in the middle of the conveyance path between the inlet roller pair 502 and the conveyance roller pair 503, and a punch unit 550 is provided in the middle of the conveyance path between the conveyance roller pair 503 and the buffer roller 505. It has been. The punch unit 550 operates as necessary, and punches near the rear end of the conveyed paper.

  The buffer roller 505 is a roller capable of laminating a predetermined number of sheets fed around the outer periphery of the buffer roller 503 via the conveying roller pair 503 and winding the sheet on the outer periphery of the roller. It is wound by 513,514. The wound paper is conveyed in the rotation direction of the buffer roller 505.

  A switching flapper 511 is disposed between the pressing rollers 513 and 514, and a switching flapper 510 is disposed on the downstream side of the pressing rollers 514. The switching flapper 511 is a flapper for separating the paper wound around the buffer roller 505 from the buffer roller 505 and guiding it to the non-sorting path 521 or the sorting path 522, and the switching flapper 510 removes the paper wound around the buffer roller 505. It is a flapper for guiding the paper wound around the sort path 522 after being peeled off from the line 505 or the buffer roller 505 to the buffer path 523 in a wound state.

  When the paper wound around the buffer roller 505 is guided to the non-sort path 521, the switching flapper 511 is operated to peel the paper wound from the buffer roller 505 and guided to the non-sort path 521. The sheet guided to the non-sort path 521 is discharged onto the sample tray 701 via the discharge roller pair 509. In the middle of the non-sort path 521, a paper discharge sensor 533 is provided.

  When the paper wound around the buffer roller 505 is guided to the buffer path 523, the switching flapper 510 and the switching flap 511 do not operate, and the paper is sent to the buffer path 523 while being wound around the buffer roller 505. A buffer path sensor 532 for detecting a sheet on the buffer path 523 is provided in the middle of the buffer path 523.

  When the paper wound around the buffer roller 505 is guided to the sort path 522, the switching flapper 511 does not operate and the switching flapper 510 operates to peel the paper wound from the buffer roller 505, and this paper is guided to the sort path 522. .

  A switching flapper 512 is disposed downstream of the sort path 522 and serves as a flapper for leading to the sort discharge path 524 or the bookbinding path 525. The sheets guided to the sort discharge path 524 are stacked on an intermediate tray (hereinafter referred to as a processing tray) 630 via a pair of conveying rollers 507. The sheets stacked on the processing tray 630 are stacked by the discharge rollers 680a and 680b after being subjected to alignment processing and stapling processing by the alignment members 641 provided on the front side and the back side as necessary. It is discharged onto the tray 700. The discharge roller 680b is supported by a swing guide 650, and the swing guide 650 swings by a swing motor (not shown) so that the discharge roller 680b contacts the uppermost sheet on the processing tray 630. When the discharge roller 680b is in contact with the uppermost sheet on the processing tray 630, the discharge roller 680b discharges the sheet bundle on the processing tray 630 toward the stack tray 700 in cooperation with the discharge roller 680a. Is possible.

  The above-described stapling process is performed by the stapler 601. The stapler 601 is configured to be movable along the outer periphery of the processing tray 630. The stapler 601 moves the sheet stack loaded on the processing tray 630 to the last position (rear end) of the sheet with respect to the sheet conveyance direction (left direction in FIG. 2). ).

  Further, the sheet guided to the bookbinding path 525 is conveyed to a bookbinding intermediate tray (hereinafter referred to as a bookbinding processing tray) 830 through a pair of conveyance rollers 802. A bookbinding entrance sensor 831 is provided in the middle of the bookbinding path 525. The bookbinding tray 830 is provided with an intermediate roller 803 and a movable paper positioning member 816. Further, an anvil 811 is provided at a position facing the two pairs of staplers 810, and the stapler 810 and the anvil 811 cooperate to perform a stapling process on a sheet bundle stored in the bookbinding processing tray 830. It has become.

  On the downstream side of the stapler 810, a folding roller pair 804 and a protruding member 815 are provided at positions opposite to the folding roller pair 804. By projecting the protruding member 815 toward the sheet bundle stored in the bookbinding processing tray 830, the sheet bundle stored in a bundle on the bookbinding processing tray 830 is pushed out between the pair of folding rollers 804. The pair of folding rollers 804 folds the sheet bundle and conveys the sheet bundle downstream. The folded sheet bundle is transferred to the trimmer 900 via the conveying roller pair 805. A paper discharge sensor 832 is provided downstream of the conveyance roller pair 804.

(Finisher block diagram)
Next, the configuration of the finisher control unit 501 that drives and controls the finisher 500 will be described with reference to FIG. FIG. 4 is a block diagram showing a configuration of the finisher control unit of FIG.

  As shown in FIG. 4, the finisher control unit 501 includes a CPU 551, a ROM 552, a RAM 553, and the like. Data is exchanged by communicating with a CPU circuit unit 150 provided on the image forming apparatus main body 10 side via a communication IC (not shown), and various programs stored in the ROM 552 are executed based on instructions from the CPU circuit unit 150. Then, drive control of the finisher 500 is performed.

  In addition, communication with a trimmer control unit 901 that controls the trimmer 900 is performed via a communication IC (not shown) separately from the image forming apparatus main body 10.

(Trimmer)
Next, the configuration of the trimmer 900 will be described with reference to FIGS. FIG. 5 is a cross-sectional view of the trimmer 900 shown in FIG. 1, and FIG.

  The trimmer 900 receives the sheet folded in the bookbinding processing unit of the finisher 500 based on the center. In order to correct the misalignment of the paper that occurs during delivery with the finisher 500, the paper dropped from the paper discharge roller 805 is sandwiched between the front alignment member 910a and the back alignment member 910b provided in the receiving portion, and is brought to the center of the conveyance path. Thereafter, the sheet is conveyed downstream by a conveying belt 902. As shown in FIGS. 5 and 6, the transport path in the trimmer 900 is provided with two pairs of transport belts 902, 903, 904, 905 at equal distances from the center of the transport path. The paper is conveyed downstream while being sandwiched between the conveyance belts.

  Between the conveyor belts 902 and 903, as shown by a broken line in FIG. 7, there is provided a configuration for cutting (hereinafter, “small edge cutting”) an end portion on the downstream side of the sheet conveyance and opposite to the center folded end portion. The conveyed paper is abutted against the fore edge stopper 911 and stops at the cutting position. Small paper cutting is performed by lowering the small edge cutting upper blade 912a that can be moved up and down facing the fixed small edge cutting lower blade 912b on the stopped paper. The fore edge stopper 911 can be moved toward and away from the conveyance belt 903 in order to convey the sheet without performing the edge cutting or for conveying the sheet downstream after the sheet cutting. In addition, it is possible to move in the transport direction in order to switch the paper stop position according to the paper size and to switch the paper stop position to adjust the cutting position (broken line display). The cut chips are stored in the small waste box 915. Normally, the small edge cutting upper blade 912a stands by at a raised position so as not to hinder the conveyance of the paper.

  Further, as shown by the broken line in FIG. 8, the conveying belt 905 provided downstream from the small edge cutting portion is provided with a configuration for cutting an end perpendicular to the center folded end (hereinafter, “upper and lower cutting”). Yes. The paper stopped by the transport belt 905 is provided with top and bottom cutting lower blades 921b and 922b fixed to the front side and the back side, and the top and bottom cutting upper blades 921a and 922a are lowered and the top and bottom cutting is performed, as in the case of the small edge cutting. . The top and bottom cutting blades 921a, 921b, 922a, and 922b are movable toward the front and back, and move according to adjustment of the paper size and the cutting position. The chips cut by the top and bottom cutting unit are stored in the top and bottom waste box 925. When the top-and-bottom cutting is not performed, the sheet is conveyed downstream without stopping by the conveyance belt 905.

  The sheet that has passed through the conveyance belt 905 is discharged onto the stacking tray 930. At this time, the transport large roller 931 on the stacking tray is also driven to move the discharged sheets on the stacking tray 930 and also move the already stacked sheets on the stacking tray 930 to the downstream side of the tray. The paper is prevented from staying at the paper discharge port.

(Trimmer block diagram)
Next, the configuration of the trimmer control unit 901 that controls the drive of the trimmer 900 will be described with reference to FIG.

  As shown in FIG. 9, the trimmer control unit 901 includes a CPU 951, ROM 952, RAM 953, and the like. Data is exchanged by communicating with a finisher control unit 501 provided in the finisher 500 via a communication IC (not shown), and various programs stored in the ROM 952 are executed on the basis of instructions from the finisher control unit 501, and the trimmer 900 Drive control is performed.

  The transport belts 902a and 902b are driven to rotate by the receiving transport motor M10, the transport belts 903a and 903b are driven by the small-end transport motor M11, the transport belts 904a and 904b are driven by the vertical path transport motor M12, and the transport belts 905a and 905b are driven by the top and bottom transport motor M13. Is done. Both are driven by a stepping motor. Further, the front alignment member 910a and the back alignment member 910b are driven by the receiving alignment motor M14 in the center direction by forward rotation and the outer direction by reverse rotation. The edge cutting upper blade 912a is driven up and down by forward / reverse rotation of the edge cutting motor M15. The edge cutting motor M15 is driven by a DC motor because the motor load varies depending on the number and thickness of sheets to be cut. The fore edge stopper 911 is moved in the conveying direction by a stopper moving motor M16, which is a stepping motor, and its position is controlled. Moreover, raising / lowering of the edge stopper 911 is driven by a stopper solenoid SL1. The top and bottom cutting upper blade 921a is also driven up and down by forward / reverse rotation of the top and bottom cutting motor M17, which is a DC motor, like the small edge cutting upper blade 912a.

(Paper flow)
Next, the flow of paper in the finisher 500 will be described along the non-sort mode, the sword mode, and the bookbinding mode.

(Non-sort operation)
First, the flow of paper in the non-sort mode will be described with reference to FIG.

  When the user designates the paper discharge mode setting in the image forming apparatus 10 as the non-sort mode, the inlet roller pair 502, the transport roller pair 503, and the buffer roller 505 are rotationally driven as shown in FIG. The paper P discharged from the printer is taken into the finisher 500 and conveyed. The switching flapper 511 is rotationally driven by a solenoid (not shown) at the illustrated position, and the paper P is guided to the non-sort path 521. When the paper discharge sensor 533 detects the trailing edge of the sheet P, the discharge roller pair 509 rotates at a speed suitable for stacking and discharges the paper P onto the sample tray 701.

(Sort mode operation)
Next, the flow of sheets in the sort mode will be described with reference to FIGS.

  When the user designates the sort mode, as shown in FIG. 11, the entrance roller pair 502, the transport roller pair 503, and the buffer roller 505 are rotationally driven, and the paper P discharged from the image forming apparatus 10 is placed in the finisher 500. Taken and transported. The respective switching flappers 510 and 511 are stopped at the illustrated positions, and the paper P is guided to the sort path 522 side. The paper P guided to the sort path 522 is guided to the sort paper discharge path 524 by the switching flapper 512 and discharged to the processing tray 630 by the transport roller pair 507. At the time of the discharge, the protruding tray 670 protruding upward prevents the paper P discharged by the conveying roller pair 507 from hanging down and returning, and improves the alignment of the paper on the processing tray 630.

  The paper P discharged onto the processing tray 630 starts to move on the processing tray 630 toward the stopper 631 by its own weight. The movement of the paper P is configured to be assisted by an assisting member such as a paddle 660 and a return belt 661. When the trailing edge of the paper P comes into contact with the stopper 631 and the paper P stops, the paper discharged by the alignment member 641 is aligned.

  Thereafter, as shown in FIG. 12, the sheet bundle P is sandwiched between the sheet discharge rollers 680 a and 680 b to perform a bundle discharge operation, and the sheet bundle P is discharged to the stack tray 700. By stacking and discharging each sheet bundle on the processing tray 630 by the alignment member 641 in an alternately offset state, each sheet bundle is stacked upward in the page order with the first page with the image forming surface facing downward as the bottom. The bundles are sequentially stacked on the stack tray 700.

(Sort mode winding operation)
The flow of each sheet forming the second set of bundles from the time when the sheet P of the first set of sheets is taken in to the time of discharge as a set of sheets will be described.

  As shown in FIG. 13, the sheet P1 of the first page in the next bundle, that is, the second set bundle discharged from the image forming apparatus 10 is wound around the buffer roller 505 by the operation of the switching flapper 510, and the buffer roller 505 is wound on the sheet P1. Is stopped at a position where a predetermined distance is conveyed from the buffer path sensor 532. When the leading edge of the paper P2 of the next page advances a predetermined distance from the entrance sensor 531, the buffer roller 505 starts rotating as shown in FIG. 14, and the next paper P2 is overlapped with the paper P1, and as shown in FIG. Then, it is conveyed again to the buffer path 532 and overlapped with the succeeding paper P3.

  Each sheet P1, P2, P3 wound around the buffer roller 505 is conveyed to the sort path 522 as three sheet bundles P by the switching flapper 510 as shown in FIG. At this time, the operation of discharging the bundle of sheets P stacked on the processing tray 630 has been completed, and is ready to be discharged onto the processing tray 630, and is discharged onto the processing tray 630.

  The fourth and subsequent sheets are discharged onto the processing tray 630 through the sort path 522 in the same manner as the sheet discharging operation for the first bundle. For the next and subsequent sheet bundles, after the second sheet bundle is discharged to the stack tray 700, the same operation is repeated, and a predetermined set number of sheet bundles are stacked on the stack tray 700.

  In the present embodiment, the process of superimposing three sheets has been described, but two or four or more sheets may be used.

(Binding mode operation)
Next, the flow of sheets in the bookbinding mode will be described with reference to FIGS.

  When the bookbinding mode is designated, the entrance roller pair 502, the transport roller pair 503, and the buffer roller 505 are rotationally driven, and the paper P discharged from the image forming apparatus 10 is taken into the finisher 500 and transported. The switching flappers 510, 511, and 512 are stopped at the illustrated positions, and the paper P is guided from the sort path 522 to the bookbinding path 525 and stored in the bookbinding processing tray 830 by the conveyance roller pair 802. The intermediate roller 803 is driven to rotate and is conveyed until the leading edge of the paper stored in the bookbinding processing tray 830 comes into contact with the paper positioning member 816. At this time, the sheet positioning member 816 is at a position where the staple processing is performed at the center of the sheet bundle stored by the stapler 810.

  When the leading edge of the sheet reaches the positioning member and the conveyance is stopped, an alignment member (not shown) operates in a direction perpendicular to the sheet conveyance direction, and the sheet is aligned. When a predetermined number of sheets are aligned and stored, the stapler 810 performs stapling (hereinafter, saddle stitching) at the center of the sheet bundle as described above.

  Then, as shown in FIGS. 18 and 19, the sheet positioning member 816 is lowered to a position where the staple position (the center of the sheet) becomes the center position of the folding roller pair 804. Then, the folding roller pair 804 and the conveying roller pair 805 are driven to rotate, and at the same time, the protruding member 815 is projected to push the sheet bundle between the folding roller pair 804. As shown in FIG. 20, the sheet bundle is conveyed downstream while being folded by the folding roller pair 804, and is discharged to the trimmer 900 by the conveying roller pair 805.

  In the case of the binding mode without saddle stitching, as in the case of saddle stitching described above, after the paper is once stored in the center of the bundle of sheets at the position where the staple processing is performed, the center of the paper is not folded and the center of the paper is folded. The positioning member 816 is lowered to a position that becomes the center position of the pair 804. Thereafter, the protruding member 815 is protruded to push the sheet bundle between the pair of folding rollers 804, and the sheet bundle is conveyed downstream while descending the pair of folding rollers 804.

(Binding mode winding operation)
The flow of each sheet forming the second set of bundles from the time when the sheet P of the first set of sheets is taken in to the time of discharge as a set of sheets will be described.

  The paper P1 of the first page in the next bundle, that is, the second set bundle discharged from the image forming apparatus 10 is wound around the buffer roller 505 by the operation of the switching flapper 510 as in the case of the second copy in the sort mode. The roller 505 is stopped at a position where the paper P1 is conveyed by a predetermined distance from the buffer path sensor 532. When the leading edge of the paper P2 of the next page advances a predetermined distance from the entrance sensor 531, the buffer roller 505 starts to rotate, and superimposes the paper P2 so that the paper P1 is ahead of the next paper P2 by a predetermined distance. As shown in FIGS. 21 and 22, the paper P2 is overlapped with the paper P1, transported again to the buffer path 532, and further overlapped with the subsequent paper P3.

  Each sheet P1, P2, P3 wound around the buffer roller 505 is conveyed to the sort path 522 as a three sheet bundle P by the switching flapper 510 as shown in FIG. At this point, the folding operation of the sheet bundle stored on the bookbinding tray 830 has been completed. Further, the sheet positioning member 816 has moved from the folding process position for the previous sheet bundle to the stapling position for the next sheet bundle, and the three sheet bundles are conveyed by the conveying roller pair 802 and the intermediate roller 803. Are stored in the bookbinding processing tray 830 and are discharged to the bookbinding processing tray 830.

  The fourth and subsequent sheets are ejected from the sort path 522 through the bookbinding path onto the bookbinding processing tray 830 in the same manner as the first sheet bundle ejecting operation.

  As described above, the operation of receiving the (N + 1) th sheet while performing the folding operation of the Nth copy in the bookbinding processing tray 830 is performed in parallel, so that the interval between the Nth copy and the (N + 1) th copy is performed. Therefore, the productivity can be prevented from being lowered.

  In the present embodiment, the process of superimposing three sheets has been described, but two or four or more sheets may be used.

(Cutting mode operation)
Next, the sheet flow in the cutting mode will be described with reference to FIGS.

  As shown in FIG. 23, when the sheet bundle P ′ that has been saddle-stitched and folded in the bookbinding mode as described above begins to be discharged from the discharge roller 805 of the finisher 500, the conveyor belts 902a and 902b are driven to rotate. When the receiving sensor 941 on the conveyance belt 902b detects the leading edge of the sheet bundle P ′, the sheet is conveyed by a predetermined distance, and when the trailing end of the sheet bundle P ′ falls on the conveyance belt 902b, the conveyance belts 902a and 902b are driven. To stop. At this time, since the leading end of the sheet does not reach the conveying belt 902a, the sheet bundle P ′ is not held by the conveying member and is in a free state, and the alignment members 910a and 910b operate in a direction perpendicular to the conveying direction. Then, an alignment operation for aligning the center of the transport path and the center of the sheet bundle is performed. When the alignment operation is completed, the conveyor belts 902a, 902b, and 903 are driven again and conveyed downstream.

  When performing fore edge cutting, the fore edge stopper is raised from the standby position indicated by the broken line to the position discharged to the conveyance path as indicated by the solid line, and further moved in the conveyance direction to a position corresponding to the amount of cutting. The sheet bundle P conveyed downstream by the conveyance belts 902 and 903 is conveyed by a predetermined distance after the leading edge of the sheet is detected by the path sensor 942, and then the conveyance belts 902 and 903 are stopped, the leading edge of the sheet comes into contact with the fore edge stopper 911, and conveyed. The belt is held between the belts 903a and 903b. At this time, the rear end of the sheet bundle P is in a state of being removed from the conveying belt 902.

  Then, as shown in FIG. 24, the small edge cutting upper blade 912a descends and the rear end side of the sheet bundle P is cut, and the cut waste Pt falls by its own weight into the small edge waste box 915 provided at the lower part of the cutting blade. And stored. When the cutting operation is finished, the fore edge stopper 911 is lowered, the conveyance path is opened, the conveyance belts 903, 904, and 905 are rotationally driven, and the sheet bundle P is further conveyed downstream.

  When the edge cutting is not performed, after the alignment operation is performed by the alignment member 910, the conveyance belts 902, 903, 904, and 905 are rotationally driven in the standby position where the edge stopper 911 is lowered, and the sheet cutting is performed at the edge cutting section. P is transported downstream without stopping.

  Next, as shown in FIG. 25, when cutting the sheet bundle P conveyed downstream by the conveyance belt 904, driving of the conveyance belt 905 is stopped after a predetermined distance is conveyed after the leading edge of the sheet is detected by the pass sensor 943. To do. While the sheet bundle P is being conveyed on the conveying belt 904, the top and bottom cutting blades 921 and 922 are moved to a position corresponding to the cutting amount, and the top and bottom cutting upper blades 921a and 922a are lowered, and the top and bottom edges of the sheet bundle P are moved. Department is cut. The trimmed scrap Ps that has been trimmed falls into the top and bottom scrap box 925 and is stored. Thereafter, when the upper cutting blades 921a and 922a are lifted, the conveying belt 905 is driven, and the sheet bundle P is discharged onto the stacking tray 930 as shown in FIG. The large conveyance roller 931 on the paper discharge tray is driven to rotate before the leading end of the paper bundle P reaches the large conveyance roller 931, and moves the paper bundle P on the paper discharge tray 930.

(Binding mode and cutting mode settings)
Next, the flow of bookbinding mode and cutting mode setting will be described with reference to FIGS.

  When the “applied mode” soft key is selected on the initial screen shown in FIG. 27, the display unit 420 switches to a screen for selecting various modes as shown in FIG. Here, when “bookbinding” is selected, as shown in FIG. 29, a key capable of selecting a cassette storing recording paper to be output is displayed. Here, when a paper of a size to be used is stored and a cassette is selected and the “Next” soft key is pressed, a screen for setting processing for a bookbinding bundle is displayed as shown in FIG. When the bookbinding mode is selected, at least half-folding is performed, but the user can select whether or not to perform saddle stitching, and selects either “saddle stitching” or “not saddle stitching”. Further, it is possible to select whether or not to perform cutting independently of saddle stitching. Here, regardless of the saddle stitch setting, when “Do not cut” is selected and the “OK” key is pressed, the setting is completed, the screen returns to the initial screen shown in FIG. 27, and the start key 402 is pressed. It will be in a state waiting for operation to be started.

  In FIG. 30, when “Cutting” is selected and the “OK” key is pressed regardless of the saddle stitch setting, a screen for setting a cutting process is displayed (see FIG. 31). Select whether to perform small edge cutting only, or to perform both small edge cutting and top and bottom cutting. When the edge cutting is selected and the “OK” key is pressed, as shown in FIG. 32, a screen for setting the length x to be cut from the edge of the sheet is displayed, and an arbitrary cutting amount can be set from the numeric keypad of the operation display unit. Become. When the “OK” key is pressed after setting the trimming amount, the setting is completed and the screen returns to the initial screen. In addition, when the three-way cutting is selected in FIG. 31, as shown in FIG. 33, the cutting amount x on the fore edge side and the cutting amount y on the top and bottom side are displayed on the operation display unit as in the case of specifying the cutting amount for the edge cutting. Enter from the numeric keypad. After input, when the “OK” key is pressed, the setting is completed and the screen returns to the initial screen.

(Paper processing in saddle stitching binding mode and cutting mode)
In the bookbinding mode setting described above, sheet processing by a combination of saddle stitching and cutting will be described with reference to FIG.

  When the setting for performing saddle stitching is made (S1000), the sheet bundle is stored in the bookbinding processing tray 830 as described above and the sheet is stapled by the stapler 810, regardless of the setting for cutting. Folding is performed in units of bundles (S1002). At the same time, the winding operation is performed for the second and subsequent copies, and the operation is continued. Thereafter, if the setting is to cut, the trimmer 900 performs cutting for each sheet bundle.

  Even when the setting for not performing saddle stitching (S1001) and the setting for not cutting, as described above, after the entire sheet bundle is stored in the bookbinding processing tray 830, the sheet bundle is not stapled by the stapler 810. Folding is performed in units, and trimming is performed for each sheet bundle with the trimmer 900 (S1002). At this time, the winding operation is performed for the second and subsequent copies.

  If the setting for not performing saddle stitching (S1001) and the setting for trimming are performed, one sheet of paper is stored in the bookbinding processing tray 830, and then folded in a centerless manner without being saddle stitched, and delivered to the trimmer 900. In 900, cutting according to the setting is performed. Only when this combination is set, folding and cutting are performed for each sheet (S1003). Further, when the winding operation is performed, two or more sheets are overlapped, and a plurality of sheets are folded and cut. Therefore, in this setting, the winding operation is not performed, and the folded sheet until the folding roller pair 804 is removed. In order to prevent the succeeding sheet from being conveyed to the bookbinding processing tray 830, a time is required until the succeeding sheet is image-formed and delivered to the finisher 500.

FIG. Overall block diagram. Finisher sectional view. Block diagram of the finisher. Sectional drawing of a trimmer. A top view of the trimmer. Explanatory drawing of cutting. Explanatory drawing of cutting. Trimmer block diagram. The figure which shows the flow of the paper at the time of non-sort mode. The figure which shows the flow of the paper at the time of sort mode. The figure which shows the flow of the paper at the time of sort mode. The figure which shows the flow of the paper at the time of sort mode. The figure which shows the flow of the paper at the time of sort mode. The figure which shows the flow of the paper at the time of sort mode. The figure which shows the flow of the paper at the time of sort mode. FIG. 6 is a diagram illustrating a flow of paper in a bookbinding mode. FIG. 6 is a diagram illustrating a flow of paper in a bookbinding mode. FIG. 6 is a diagram illustrating a flow of paper in a bookbinding mode. FIG. 6 is a diagram illustrating a flow of paper in a bookbinding mode. FIG. 6 is a diagram illustrating a flow of paper in a bookbinding mode. FIG. 6 is a diagram illustrating a flow of paper in a bookbinding mode. The figure which shows the flow of the paper at the time of cutting mode. The figure which shows the flow of the paper at the time of cutting mode. The figure which shows the flow of the paper at the time of cutting mode. The figure which shows the flow of the paper at the time of cutting mode. Explanatory drawing of an operation display part. The figure which shows the flow of setting of bookbinding and cutting mode. The figure which shows the flow of setting of bookbinding and cutting mode. The figure which shows the flow of setting of bookbinding and cutting mode. The figure which shows the flow of setting of bookbinding and cutting mode. The figure which shows the flow of setting of bookbinding and cutting mode. The figure which shows the flow of setting of bookbinding and cutting mode. Explanatory drawing of folding operation | movement. Paper processing discrimination flow in bookbinding mode. Explanatory drawing of a bookbinding bundle.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Image forming apparatus 100 Document feeding apparatus 200 Image reader 300 Printer 400 Operation display apparatus 500 Finisher 630 Intermediate tray 830 Bookbinding intermediate tray 900 Trimmer

Claims (2)

In an image forming apparatus that forms an image on a sheet and a sheet post-processing apparatus that sequentially receives sheets formed by the image forming apparatus,
Saddle stitching means for binding the center of the image-formed paper,
Folding means for folding the center of the image-formed paper,
A cutting means for cutting a sheet end portion of the sheet bundle folded by the middle folding means;
A setting means for setting saddle stitching, center folding, and cutting processing in the sheet post-processing apparatus;
According to the combination of whether or not to perform saddle stitching set by the setting means and whether or not to perform cutting, a first half-folding mode in which a plurality of sheets are folded at the same time and a second half-folding of the sheets one by one An image forming system comprising: control means for switching the middle folding mode. In claim 1,
When the setting unit is set to perform cutting without saddle stitching, the second half-folding mode is selected, and when the setting is such that the sheet is folded and cut for each sheet and is not subjected to saddle stitching. The image forming system according to claim 1, wherein the first half-fold mode is selected, and a plurality of sheets are folded and cut simultaneously.

Images