JP2006076721A - Sheet handling device and image forming device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sheet handling device capable of loading a bundle of sheets in a stack tray, while aligning them, in the case of discharging the sheet bundle (loading paper) loaded in an intermediate tray after an operator eliminates the sheet bundle (loading paper) loaded in a stack tray, and to provide an image forming device. <P>SOLUTION: When discharging the sheet bundle loaded in the intermediate tray 410 to an upper stage stack tray 421 (or a lower stage stack tray 422), a CPU of a control unit as a control means operates an upper stage stack tray motor 467 (or a lower stage stack tray motor 468) to move the upper stage stack tray 421 (or the lower stage stack tray 422) to the predetermined position in the case wherein determination that the upper stage stack tray 421 (or the lower stage stack tray 422) is not positioned in the predetermined position is done on the basis of the tray position detecting information by a home position sensor 461. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

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

  As a conventional sheet processing apparatus, after aligning both sides of a sheet bundle stacked on an intermediate tray along the sheet conveyance direction with an alignment means having a pair of alignment members, the sheet bundle is moved to a stack tray that can be raised and lowered. Some are configured to be discharged and stacked (for example, see Patent Document 1).

  In this case, since the position of the stack tray is slightly lower than the position of the intermediate tray, the distance between the sheets (paper sheets) stacked on the intermediate tray and the stacked paper surface on the stack tray is kept constant.

  By the way, the conventional sheet processing apparatus as described above receives a stack of sheets from the stack tray when the operator removes the stacked sheets from a state where a large number of sheets (stacked sheets) are stacked on the stack tray. It is necessary to raise it to the highest possible height. At this time, when a large number of sheets (stacked sheets) are stacked on the intermediate tray, the stack tray is raised at the start of the next image forming operation, and the sheet bundle discharging operation is performed.

Japanese Patent No. 2583594

  By the way, in the conventional sheet processing apparatus described above, when the operator removes the stacked sheets from a state in which a large number of sheets (stacked sheets) are stacked on the stack tray, that is, the position of the stack tray is not at a predetermined reference position. In this case, if the stack of sheets loaded on the intermediate tray is forcibly discharged, the stack of sheets may be at the bottom, causing the sheet bundle to be curled and discharged when the sheet is unbundled. In some cases, the stack tray was not loaded with good alignment.

  Accordingly, the present invention provides a sheet processing that allows a stack of sheets to be stacked with good alignment by raising the position of the stack tray when discharging the stacked sheets on the intermediate tray when the operator removes the stacked sheets on the stack tray. An object is to provide an apparatus and an image forming apparatus.

  In order to achieve the above object, the present invention includes a first sheet stacking unit on which sheets are stacked, and a second sheet stacking unit that can be moved up and down on which sheets are discharged and stacked from the first sheet stacking unit. Sheet discharge means for discharging the sheets stacked on the first sheet stacking means to the second sheet stacking means, and stacked sheet detection means for detecting the presence / absence of sheets stacked on the second sheet stacking means A tray position detecting means for detecting the position of the second sheet stacking means, a moving means for moving the second sheet stacking means in the vertical direction, and operating the moving means to operate the second sheet. Control means for moving the stacking means up and down, and the control means detects the tray position when discharging the sheets stacked on the first sheet stacking means to the second sheet stacking means. When it is determined that the second sheet stacking unit is not at the predetermined reference position based on the tray position detection information by the stage, the moving unit is operated to move the second sheet stacking unit to the predetermined reference position. It is designed to move.

  In addition, the sheet discharge unit discharges the sheet to the second sheet stacking unit after the second sheet stacking unit has moved to a predetermined reference position.

  An image forming apparatus according to the present invention includes: an image forming unit that forms an image on a sheet; and the sheet processing apparatus according to any one of the above that processes a sheet on which an image is formed by the image forming unit. It is characterized by that.

  The image forming apparatus according to the present invention includes an image forming unit that forms an image on a sheet, a first sheet stacking unit on which a sheet on which an image is formed by the image forming unit is stacked, and a sheet that is the first sheet stacking unit. Second sheet stacking means that can be moved up and down and discharged from the sheet stacking means, and a sheet discharge means for discharging the sheets stacked on the first sheet stacking means to the second sheet stacking means, A stacked sheet detecting means for detecting the presence or absence of sheets stacked on the second sheet stacking means, a tray position detecting means for detecting the position of the second sheet stacking means, and the second sheet stacking means are moved up and down. Moving means for moving in the direction, and control means for operating the moving means to move the second sheet stacking means up and down, wherein the control means is connected to the first sheet stacking means. When it is determined that the second sheet stacking unit is not at a predetermined reference position based on the tray position detection information by the tray position detection unit when discharging the loaded sheet to the second sheet stacking unit. Is characterized by operating the moving means to move the second sheet stacking means to a predetermined reference position.

  According to the present invention, when the sheets stacked on the first sheet stacking unit are discharged to the second sheet stacking unit, the second sheet stacking unit is predetermined based on the tray position detection information by the tray position detecting unit. If it is determined that the second sheet stacking unit is not located, the second sheet stacking unit can be moved to a predetermined position by operating the moving unit. For example, the operator has discharged the second sheet stacking unit to the second sheet stacking unit. After the sheet bundle is removed, when the sheet bundle stacked on the first sheet stacking unit is discharged to the second sheet stacking unit, the second sheet stacking unit moves upward and is set at a predetermined position. As a result, the sheet bundle can be discharged to the second sheet stacking unit with good stacking alignment.

  The best mode for carrying out the present invention will be described below with reference to the drawings.

  FIG. 1 is a schematic front sectional view showing a copying machine as an example of an image forming apparatus including a sheet processing apparatus according to an embodiment of the present invention, and FIG. 2 is a schematic diagram showing the sheet processing apparatus according to the embodiment of the present invention. It is front sectional drawing.

  As shown in FIG. 1, a sheet processing apparatus 400 for processing a sheet on which a toner image discharged from the apparatus main body 11 is formed is connected to the side surface of the apparatus main body 11 of the copying machine 10 (sheet processing apparatus 400). Will be described later in detail). The apparatus main body 11 of the copying machine 10 includes a reader unit 100 and a printer unit 200.

  The reader unit 100 includes a document table glass 101 on which documents (not shown) are stacked, a scanner unit 106 including an illumination lamp and a mirror for reading a document sent from the automatic document feeder 300, and a document table glass. 101, a scanning reflection mirror (scanning mirror) 103, 104 for irradiating the original on 101 from the scanner unit 106 to change the optical path of the reflected light, a lens system 105 having a function of focusing and scaling the reflected light, It has a CCD image sensor unit 126 and the like.

  The apparatus main body 11 includes a registration roller 107, a photosensitive drum 108 exemplified as an image forming unit, a charger 127, a developing unit 109, a transfer unit 110, and the like, and forms a latent image corresponding to a document on the photosensitive drum 108. A laser unit 122, a polygon mirror 123, a mirror 125 for changing an optical path, and the like. Further, the apparatus main body 11 includes a conveyance belt 111 that conveys a sheet of plain paper or the like on which a toner image is formed to the fixing roller 112 side, a fixing roller 112 that thermocompresses the toner image on the conveyed sheet, and a sheet. Conveying roller 113 for conveying, flappers 114 and 117 for switching the conveying direction of the conveyed sheet, conveying roller 115 for conveying the sheet to the sheet processing apparatus 400 side, flapper 120 and reversing path 116 for reversing the front and back of the sheet, each cassette A pickup roller 119 that picks up a sheet from the sheet 203, a feeding roller 118 that pulls out the sheet from each cassette 203, a conveying roller 201 that transfers the sheet pulled out from each cassette 203 upward, and an intermediate roller 202 are provided.

  During the image forming operation by the copying machine 10, a document placed on the platen glass 101 is optically read by the scanner unit 106, and the CCD is passed through the scanning reflection mirrors (scanning mirrors) 103 and 104 and the lens system 105. Output to the image sensor unit 126. The CCD image sensor unit 126 performs electrical processing such as photoelectric conversion on the input image data and performs digital signal processing. The digitally processed image signal is converted into a modulated optical signal by the laser unit 122, and the photosensitive drum 108 charged by the charger 127 is irradiated with the laser beam L to form a latent image. This latent image is developed by the developing device 109 to form a toner image on the photosensitive drum 108.

  The sheet P set in each cassette 203 is conveyed to the registration roller 107 by the pickup roller 119, the feeding roller 118, the conveying roller 201, and the intermediate roller 202. The registration roller 107 sends the sheet to the photosensitive drum 108 by aligning the leading edge of the toner image with the leading edge of the sheet at an accurate timing. Thereafter, the sheet passes between the photosensitive drum 108 and the transfer device 110, whereby the toner image on the photosensitive drum 108 is transferred onto the sheet.

  Thereafter, the sheet is separated from the photosensitive drum 108 and conveyed to the fixing roller 112 by the conveying belt 111, and the toner image is fixed on the sheet by pressure and heating at the nip portion. The sheet on which the toner image is fixed in this manner is sent into the apparatus main body 400A of the sheet processing apparatus 400 by the guidance of the flapper 114 and the conveyance of the paper discharge roller 115 with the toner image surface facing up. Further, in order to send the toner image side down to the sheet processing apparatus 400, the sheet is once sent to the reversing path 116 by the guidance of the flappers 114, 117, 120 and the rotation of the conveying roller 121, and then the back of the sheet. When the end passes through the flapper 117, the flapper 117 is switched, the conveying roller 121 is reversed, and the sheet passes through the passage on the left side of the flapper 117 and is fed into the sheet processing apparatus 400.

  Further, to form a toner image on the other side of the sheet (double-sided image formation), that is, to form a toner image on both sides of the sheet, the guide of the flappers 114, 117, 120 and the rotation of the conveying roller 121 are used. After the sheet on which the toner image is fixed on one surface is sent to the reversing path 116 by the above image forming operation, the flapper 120 is switched when the trailing edge of the sheet passes through the flapper 120, and the conveying roller 121 is reversed. To the return path 124. When the sheet is fed into the return path 124, the sheet is reversed, and the toner image is formed on the other surface by the photosensitive drum 108 through the return path 124 as described above. The sheet is sent to the sheet processing apparatus 400 after being fixed by the fixing roller 112.

  Next, the sheet processing apparatus 400 will be described.

  FIG. 2 is a cross-sectional view showing the sheet processing apparatus 400. A sheet receiving unit 401 is provided on the side surface of the apparatus main body 400 A of the sheet processing apparatus 400 connected to the apparatus main body 11 of the copying machine 10, and a sheet discharged from the apparatus main body 11 side enters the sheet receiving unit 401. When the sheet enters, the entrance sensor 403 detects the sheet that has entered the sheet receiving unit 401, rotates the conveyance roller 407 by driving the conveyance motor 450, and discharges the sheet onto the intermediate tray 410 exemplified as the first sheet stacking unit. The intermediate tray sheet sensor 415 detects the sheets P stacked on the intermediate tray 410.

  By the sheet detection by the inlet sensor 403 and the intermediate tray sheet sensor 415, the bundle discharge motor 473 rotates in the reverse direction to rotate the bundle return member 409. The bundle returning member 409 moves the sheet P to the right in FIG. At this time, a stopper 419 protruding integrally with the bundle discharge belt 417 protrudes on the intermediate tray 410. Note that the position of the stopper 419 shown in FIG. 2 is a retracted position. The stopper 419 receives the rear end portion of the sheet P, which is an edge that intersects the conveyance direction of the sheet P. By the rotation operation of the bundle returning member 409 and the reception of the sheet bundle by the stopper 419, a rear end alignment operation for aligning the rear ends of the sheet bundle is performed.

  Also, the alignment member moving motors 447a and 447b shown in FIG. 4 are started, and the alignment members 413a and 413b perform a side edge alignment operation for aligning the side edge portions along the sheet conveyance direction. As described above, the sheets P sequentially discharged to the intermediate tray 410 are aligned on the intermediate tray 410 by the bundle return member 409, the stopper 419, and the alignment members 413a and 413b to form a sheet bundle.

  Here, the operation of the aligning unit 490 (see FIG. 4) as an aligning unit for aligning the sheet bundle will be described.

  When the alignment member moving motors 447a and 447b are operated, the pinions 445a and 445b provided on the rotation shafts of the alignment member moving motors 447a and 447b rotate. Then, the racks 443a and 443b engaged with the pinions 445a and 445b move, and the alignment members 413a and 413b integrated with the racks 443a and 443b approach each other. Then, the aligning plate 442 and the aligning member 413b on the aligning member 413a sandwich the sheet bundle from both sides of the sheet bundle and perform the side end alignment of the sheet bundle.

  At this time, when the sheet width varies or the alignment members 413a and 413b move too much, the alignment plate 442 presses the pair of alignment springs 441 and retreats. As a result, the aligning unit 490 reliably aligns the sheet bundle or absorbs excessive movement, so that alignment is performed based on the aligning member 413a. In addition, a clock disk 493 is integrally provided in an alignment member moving motor 447b that moves the alignment member 413b.

  An alignment member clock sensor 492 faces the clock disk 493. The amount of movement of the alignment member 413a is determined by the counter 416 in the CPU 1001 (see FIG. 8) as a control means described later counting the clock pulse generated when the alignment member clock sensor 492 detects the rotation of the clock disk 493. Detected by.

  Therefore, the alignment unit 490 can perform the side edge alignment according to the sheet size by the CPU 1001 controlling the alignment member moving motors 447a and 447b based on the sheet size information input by the user. ing. The alignment members 413a and 413b of the alignment unit 490 of this embodiment are moved by separate alignment member moving motors 447a and 447b, but may be moved by a common motor. Moreover, although both the alignment members 413a and 413b move, you may make it fix only one and move only the other.

  When the sheet bundle is created by the aligning unit 490, the staple unit 600 binds the sheet bundle. Then, the bundle discharge motor 473 rotates forward. A bundle discharge belt 417 exemplified as a sheet discharge means is circulated by a bundle discharge motor 473, and a rear end of the sheet bundle is pushed by a stopper 419 integrally projecting on the bundle discharge belt 417 to serve as a second sheet stacking means. The sheet bundle is discharged onto the upper stack tray 421 illustrated. At this time, a sheet sensor 462 (see FIG. 2) as a stacked sheet detection unit detects a sheet on the upper stack tray 421.

  When the upper stack tray 421 is moved up and down, an upper stack tray motor 467 (see FIG. 3) as a moving means rotates a gear 704 provided on a drive shaft of the motor, and a rack gear 703 engaged with the gear 704 is moved. This is done by raising and lowering. The upper stack tray motor 467 is provided with a clock disk 700 that detects the rotation of the upper stack tray motor 467 and the amount of movement of the upper stack tray 421. An upper stack tray clock sensor 466 is opposed to the clock disc 700. The elevating position of the upper stack tray 421 is counted by a counter 416 in the CPU 1001 (see FIG. 8), which is a clock pulse generated when the upper stack tray clock sensor 466 serving as the tray position detecting means detects the rotation of the clock disc 700. Is detected.

  Similarly, when the lower stack tray 422 exemplified as the second sheet stacking means is moved up and down, the lower stack tray motor 468 (see FIG. 3) as the moving means rotates the gear 705 provided on the drive shaft of this motor. The rack gear 703 meshing with the gear 705 is moved up and down. The lower stack tray motor 468 is provided with a clock disk 701 that detects the rotation of the lower stack tray motor 468 and the amount of movement of the lower stack tray 422. A lower stack tray clock sensor 482 faces the clock disk 701. As for the raising / lowering position of the lower stack tray 422, a counter pulse 416 in the CPU 1001 (see FIG. 8) counts a clock pulse generated when the lower stack tray clock sensor 482 as the tray position detecting means detects the rotation of the clock disk 701. Is detected.

  In FIG. 2, when the sheet bundle is discharged to the upper stack tray 421, the upper stack tray 421 is lowered until the home position detection sensor 461 as the tray position detecting means is turned off, and the bundle discharge belt 417 is moved to the home position position ( After returning to the same position as the stopper 419, the upper stack tray 421 is raised until the home position detection sensor 461 is turned on. The descending amount at this time counts the clock pulse by the upper stack tray clock sensor 466, and when rising, the rising amount is similarly detected by the pulse count by the upper stack tray clock sensor 466, and the upper stack tray 421 moves. The CPU 1001 detects the height of the sheet based on the amount difference and completes a series of stapling operations.

  As shown in FIG. 2, the sheets P stacked on the intermediate tray 410 protrude into the up and down area of the upper stack tray 421 so as not to slip off from the intermediate tray 410, and enter the intermediate tray 410 and the upper stack tray 421. It is designed to be loaded across. This is to reduce the size of the sheet processing apparatus 400 by using the lifting / lowering area of the upper stack tray 421, and accordingly, the alignment members 413 a and 413 b can reliably perform sheet width alignment. 1 and 2, the left end (downstream side in the sheet conveying direction) protrudes outward from the apparatus main body 400 </ b> A of the sheet processing apparatus 400.

  FIG. 7 is a block diagram showing the configuration of the control system of the copying machine 10.

  The apparatus main body 11 includes a control unit 1 of the reader unit 100, a control unit 2 of the printer unit 200, and a control unit 3 of an external device. The control unit 1 of the reader unit 100 performs movement control of the scanner unit 106 and the like in the reader unit 100. The control unit 2 of the printer unit 200 performs operation control of a motor that rotates a roller in the printer unit 200 and a plunger that tilts a flapper. The control unit 3 of the external device is connected to a telephone line, a personal computer (PC), a word processor (WS), and the like, and is connected to the control unit 1 of the writer unit 100 to process an external signal and process the reader unit 100. Control such as sending to the control unit 1 or sending the signal of the control unit 1 of the reader unit 100 to the outside is performed.

  The control unit 900 of the automatic document feeder 300 is connected to the control unit 1 of the reader unit 100, and the automatic document feeder 300 is configured to reliably and accurately read a document by cooperative control with the reader unit 100. The automatic document feeder 300 can reliably feed the document to the reader unit 100 by controlling a motor for rotating the inner roller and a plunger for tilting the flapper. The control unit 1000 of the sheet processing apparatus 400 is connected to the control unit 2 of the printer unit 200, and exchanges data with the control unit 2 of the printer unit 200 by a bus or serial communication, etc., and rotates a roller. In addition, by controlling a plunger or the like that tilts the flapper, the sheet is reliably received from the printer unit 200 of the apparatus main body 11, and the width control of the sheet bundle and the control for binding the sheet bundle are performed.

  Note that the control unit 1000 of the sheet processing apparatus 400 may be incorporated into the control unit 2 of the printer unit 200 and integrated with the control unit 2. In this case, the sheet processing apparatus 400 may be separate from the printer unit 200 of the copying machine 10 or may be incorporated in the printer unit 200.

  FIG. 8 is a block diagram illustrating a configuration of the control unit 1000 as a control unit in the sheet processing apparatus 400.

The CPU 1001 in the control unit 1000 includes a ROM 1005, and the ROM 1005 stores programs and the like corresponding to operation procedures shown in FIGS. The CPU 1001 reads out and executes these programs, and controls each unit. Further, the CPU 1001 controls each unit based on work data stored in the RAM 1003, calculation data of the CPU 1001 itself, input data from the control unit 2 of the printer unit 200, and the like. Further, the CPU 1001 controls each unit based on adjustment data such as a position correction value stored in the E ² PROM 1007. The position correction value includes, for example, a value for correcting variation in the amount of movement of the alignment members 413a and 413b, which are different for each manufactured sheet processing apparatus, from a predetermined reference position.

  The CPU 1001 exchanges data with the control unit 2 of the printer unit 200 through the communication IC 1009 to control each unit in the apparatus main body 400A of the sheet processing apparatus 400. Various sensors described later are connected to the input port of the CPU 1001, and various motors described later connected to the output port according to a program stored in the ROM 1005 and plungers (not shown) are connected based on signals from these sensors. Control the load.

  As shown in FIG. 8, the input port of the CPU 1001 includes an inlet sensor 403, a sheet sensor 462 of the upper stack tray 421, a sheet sensor 469 of the lower stack tray 422, a home position detection sensor 461, a stack tray upper limit sensor 465, an intermediate tray. Sensors such as a sheet sensor 415, a stack tray lower limit sensor 463, an upper limit stack tray clock sensor 466, a lower limit stack tray clock sensor 482, and an alignment member clock sensor 492 are connected.

  The entrance sensor 403 detects a sheet that has entered the apparatus main body 400 </ b> A of the sheet post-processing apparatus 400 from the sheet receiving unit 401. The sheet sensor 462 of the upper stack tray 421 detects whether or not sheets are stacked on the upper stack tray 421. A sheet sensor 469 for the lower stack tray detects whether sheets are stacked on the lower stack tray 422.

  The home position detection sensor 461 detects whether or not the upper stack tray 421 and the lower stack tray 422 on which sheets are not stacked are at a home position where the sheets stacked on the intermediate tray 410 can be received.

  The stack tray upper limit sunsa 465 detects whether or not the upper stack tray 421 is moved up and down to the top of the lifting range. The intermediate tray sheet sensor 415 detects whether or not the sheet is discharged and stacked on the intermediate tray 410 by the transport roller 407. The stack tray lower limit sensor 463 detects whether or not the lower stack tray 422 is lowered to the lowermost part of the lifting / lowering range.

  The upper limit stack tray clock sensor 466 detects the rotation of the clock disk 700 that rotates as the upper limit stack tray 421 moves up and down, and detects the current position of the upper limit stack tray 421 in cooperation with the counter 416 in the CPU 1001. . The lower limit stack tray clock sensor 482 detects the rotation of the clock disk 701 that rotates as the lower limit stack tray 422 moves up and down, and detects the current position of the lower limit stack tray 422 in cooperation with the counter 416 in the CPU 1001. . The alignment member clock sensor 492 detects the rotation of the clock disc 493 that rotates as the alignment member 413b moves, and detects the current position of the alignment member 413b in cooperation with the counter 416 in the CPU 1001.

  As shown in FIG. 8, the output port of the CPU 1001 includes a transport motor 450, an alignment member moving motor 447a, an alignment member moving motor 447b, a bundle discharge motor 473, an upper stack tray motor 467, and a lower stack tray motor 468. Etc. are connected.

  The conveyance motor 450 rotates the conveyance roller 407 and conveys the sheet that has entered the apparatus main body 400 </ b> A of the sheet processing apparatus 400 from the sheet receiving unit 401 to the intermediate tray 410. The alignment member moving motor 447a rotates the pinion 445a to move the alignment member 413a. The alignment member moving motor 447b rotates the pinion 445b to move the alignment member 413b. The bundle discharge motor 473 rotates the bundle return member 409 and the bundle discharge belt 417. The upper stack tray motor 467 moves the upper stack tray 421 up and down, and the lower stack tray motor 468 moves the lower stack tray 422 up and down.

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

(Operation of the sheet processing apparatus 400 at the start of copying)
As shown in the flowchart of FIG. 9, first, the CPU 1001 determines whether or not the printer unit 200 of the copying machine 10 has started a copying operation (image forming operation) (step S1001). This determination is a determination as to whether a copy start signal or a sheet discharge signal is sent from the control unit 2 of the printer unit 200. Then, it is determined whether or not the sheet is discharged from the apparatus main body 11 (step S1002). If the sheet is not discharged from the apparatus main body 11, the CPU 1001 determines whether or not printing is started again, and the printer unit. Prepare for 200 emergency stops. Thereafter, when the sheet is discharged from the apparatus main body 11, the CPU 1001 performs sheet post-processing control described later (step S1003). When the copying operation is completed, it is determined again whether the printer unit 200 has started the copying operation (step S1001). ).

(Sheet post-processing control)
As shown in the flowchart of FIG. 10, first, the CPU 1001 starts the conveyance motor 450 and sets the sheet processing apparatus 400 in a standby state so that the sheet can be conveyed whenever the sheet is fed into the sheet processing apparatus 400. (Step S1101) Wait until the sheet conveyed from the printer unit 200 can be detected by the entrance sensor 403. When the sheet passes the entrance sensor 403 (step S1102), the counter 416 in the CPU 1001 starts counting the conveyance clock (step S1103). The CPU 1001 causes the counter 416 to continue counting until the count number of the counter 416 reaches a predetermined value. When the value of the counter 416 reaches a predetermined value and the clock count ends (step S1104), the CPU 1001 determines that the sheet has reached the intermediate tray 410 and stops the rotation of the transport motor 450 (step S1105). ).

  Then, the CPU 1001 rotates the bundle return member 409 to move the sheet to the right in FIG. 2 to contact the stopper 419 in order to align the trailing edge of the sheets stacked on the intermediate tray 410 (step S1106). ). Further, the CPU 1001 operates the alignment members 413a and 413b shown in FIG. 4 to perform sheet side edge alignment (step S1107).

  Thereafter, the CPU 1001 determines the presence or absence of a stapling request signal transmitted from the control unit 2 of the printer unit 200 (step S1108), and operates the stapling unit 600 to bind the sheet bundle only when there is a stapling request (stapling). (Step S1109).

  The CPU 1001 determines whether or not there is a signal for discharging the sheet bundle transmitted from the control unit 2 of the printer unit 200 regardless of whether or not there is a stapling request (step S1110). When the detection sensor 461 is ON (step S1111), the bundle discharge belt 417 is circulated and the trailing end of the sheet bundle is pushed by the stopper 419 and discharged to the upper stack tray 421 or the lower stack tray 422 (step S1113). If the home position detection sensor 461 is OFF in step S1111, tray home position processing control (tray home position SUB), which is a feature of the present invention described later, is performed (step S1112), and the bundle discharging operation is performed. This is executed to discharge the sheet bundle (step S1113).

(Tray home position SUB)
As shown in the flowchart of the tray home position SUB (step S1112 in FIG. 10) shown in FIG. 11, when the home position detection sensor 461 is OFF (step S1121), the upper stack tray 421 or the lower stack tray 422 is raised (step S1121). Step S1122). Then, the process waits until the home position detection sensor 461 is turned on (step S1123). When the home position detection sensor 461 is turned on, the raising of the upper stack tray 421 or the lower stack tray 422 is stopped (step S1124).

  With this tray home position SUB, the operator removes the sheet bundle (stacked paper) stacked on the upper stack tray 421 (or the lower stack tray 422), and then the sheet bundle (stacked paper) stacked on the intermediate tray 410. In the case of discharging the sheet bundle, the sheet bundle can be stacked on the upper stack tray 421 (or the lower stack tray 422) with good alignment.

(Tray switching operation)
As shown in the flowchart of FIG. 12, during the switching operation between the upper stack tray 421 and the lower stack tray 422, the CPU 1001 waits for a determination as to whether or not to switch between the upper stack tray 421 and the lower stack tray 422 (in the case of “NO”). Is in a waiting state) (step S1201). This determination is a determination as to whether a signal for specifying a tray (including a switching instruction) is sent from the control unit 2 of the printer unit 200 to the control unit 1000 of the sheet processing apparatus 400.

  In step S1201, when there is an instruction to switch trays from the control unit 2 of the printer unit 200, the above-described sheet post-processing control (see FIG. 10) is performed (step S1202), and when this sheet post-processing is completed, the alignment member 413a. , 413b are moved to the retracted position (step S1203), and then a tray switching process (step S1204) is performed. As a result, the tray is switched from the upper stack tray 421 to the lower stack tray 422 or from the lower stack tray 422 to the upper stack tray 421.

(Consistent save processing)
As shown in the flowchart of the alignment saving process (step S1203 in FIG. 12) shown in FIG. 13, the CPU 1001 waits for a determination as to whether the alignment saving operation is permitted (step S1301). When the sheet is not sent from the apparatus main body 11 and the sheet alignment is completed, the CPU 1001 determines that the alignment retreat operation is permitted, and determines whether or not the current current position of the alignment members 413a and 413b is the retreat position. Judgment is made (step S1302).

  If it is determined in step S1302 that the alignment / retraction operation is permitted and the alignment members 413a and 413b are at the retraction position, the alignment / retraction process is terminated. In step S1302, if the alignment members 413a and 413b are not in the retracted position, the CPU 1001 controls the alignment plate moving motors 447a and 447b to move the alignment members 413a and 413b to the retracted position (step S1303). ).

  The retracted positions of the alignment members 413a and 413b are detected by the cooperative operation of the clock sensor 492 (see FIG. 4) and the counter 416 (see FIG. 8). The retracted positions of the alignment members 413a and 413b are positions wider than the maximum width of the sheets stacked on the intermediate tray 410. That is, as shown in FIG. 5, the upper stack tray 421 is formed with, for example, notches 423 and 424 which are interference avoiding portions corresponding to the retracted positions of the alignment members 413a and 413b.

  There may be three or more trays. In this case, it is necessary to form the notches 423 and 424 with respect to a tray that moves to a position (height) that interferes with the alignment members 413a and 413b by at least vertical movement of the plurality of trays. In this embodiment, it is necessary to form notches 423 and 424 in at least the uppermost tray (upper stack tray 421). When the alignment members 413a and 413b move to the retracted position (step S1304), the CPU 1001 stops the movement of the alignment members 413a and 413b (step S1305).

(Tray switching process)
As shown in the flowchart of the tray switching process shown in FIG. 14 (step S1204 in FIG. 12), the CPU 1001 takes time T1 until the alignment members 413a and 413b move from the current position where the side edge alignment of the sheet bundle is performed to the retracted position. And a time T2 during which the upper stack tray 421 moves from the current position to the position of the alignment members 413a and 413b (retracted position) is determined to determine whether T1 <T2 (step S1401). The current positions of the alignment members 413 a and 413 b can be detected by the clock sensor 492 and the counter 416 in the CPU 1001. Further, the current position of the upper stack tray 421 can be detected by the clock disk 700 and the counter 416.

The time T1 is the amount of movement of the aligning members 413a and 413b (the distance from the current position of the aligning members 413a and 413b where the sheet side edge alignment is performed to the retracted position) W1, and the retracting speed S1 of the aligning members 413a and 413b. Then
T1 = W1 ÷ S1 (Formula 1)
It becomes.

In addition, the time T2 moves down the upper stack tray 421 when the upper stack tray 421 travel distance (lifting distance) L1, the upper stack tray 421 moving speed (lifting speed) S2, and when the sheet is discharged to the upper stack tray 421. If the position is C1, and the distance from the C1 position to the retracted position of the upper stack tray 421 is C2,
T2 = (C1-C2) ÷ S2 (Expression 2)
It becomes. When there is no sheet on the upper stack tray 421, C1 = C2.

  If T1 <T2 in step S1401, the CPU 1001 permits an alignment retreat operation for moving the alignment members 413a and 413b to the retreat position (step S1402), and executes a tray switching operation SUB described later (step S1403). ). When the alignment members 413a and 413b move to the retracted position (S1404), the lifting operation of the upper stack tray 421 is finished, and the tray switching is finished (step S1405).

  Since T1 <T2 in the retracting operation of the alignment members 413a and 413b and the lifting operation of the upper stack tray 421, the alignment members 413a and 413b move to the retracted position before the upper stack tray 421, Thereafter, the upper stack tray 421 reaches the position of the alignment members 413a and 413b, and the notches 423 and 424 pass through the alignment members 413a and 413b, so that the upper stack tray 421 interferes with the alignment members 413a and 413b. There is no.

  In step S1401, when T1 <T2 is not satisfied (that is, when T1 ≧ T2), the CPU 1001 permits the alignment retreat operation for moving the alignment members 413a and 413b to the retreat position (step S1406). In this case, since T1 ≧ T2, the upper stack tray 421 reaches the position of the alignment members 413a and 413b and interferes with the alignment members 413a and 413b before the alignment members 413a and 413b move to the retracted position. There is a fear.

  Therefore, the CPU 1001 increases the moving speed of the alignment members 413a and 413b, slows the lifting / lowering speed of the upper stack tray 421, delays the start of lifting / lowering of the upper stack tray 421, so that T1 <T2. Control is performed to temporarily stop during raising and lowering (step S1407). In step S1407, if T1 <T2 based on the control signal from the CPU 1001, a tray switching operation SUB described later is executed (S1408).

  When the alignment members 413a and 413b move to the retracted position after the tray switching operation SUB is finished (step S1409), the lifting operation of the upper stack tray 421 is finished and the tray switching is finished (step S1410). Also in this case, the alignment members 413a and 413b move to the retracted position before the upper stack tray 421, and then the upper stack tray 421 reaches the position of the alignment members 413a and 413b, so that the notches 423 and 424 are aligned. Since it passes through 413a and 413b, the upper stack tray 421 does not interfere with the alignment members 413a and 413b.

(Tray switching operation SUB)
As shown in the flowchart of the tray switching operation SUB (step S1408 in FIG. 14) shown in FIG. 15, the CPU 1001 determines whether the upper stack tray 421 or the lower stack tray 422 is in the tray home position detection sensor 461. (Step S1501). In this determination, when the sheet processing apparatus 400 performs an initial operation, either the upper stack tray 421 or the lower stack tray 422 is moved up and down to the position of the home position detection sensor 461 of the tray, and the tray is stored in the RAM 1003. Therefore, it is performed based on the memory.

  When the home position detection sensor 461 determines that the upper stack tray 421 is detected in step S1501, the CPU 1001 operates the upper stack tray motor 467 to raise the upper stack tray 421 as shown in FIG. 6 (step S1502). When the stack tray upper limit sensor 465 detects the upper limit of the upper stack tray 421 (step S1503), the CPU 1001 stops the upper stack tray motor 467, stops the upper stack tray 421, and operates the lower stack tray motor 468. Thus, the lower stack tray 422 is raised (step S1504).

  When the home position detection sensor 461 detects the lower stack tray 422 (step S1505), the CPU 1001 stops raising the lower stack tray 422 (step S1506).

  If the home position detection sensor 461 determines that the lower stack tray 422 is detected in step S1501, the CPU 1001 operates the lower stack tray motor 468 to lower the lower stack tray 422 (step S1507). When the stack tray lower limit detection sensor 463 detects the lower limit of the lower stack tray 422 (step S1508), the CPU 1001 stops the lower stack tray motor 468, stops the lower stack tray 422, and moves the upper stack tray motor 467. The upper stack tray 421 is lowered by operating (step S1509). When the home position detection sensor 461 detects the upper stack tray 421 (step S1510), the CPU 1001 stops the lowering of the upper stack tray 421 (step S1511).

  Note that the tray switching operation of this embodiment starts and ends the operation of one upper stack tray 421 (or lower stack tray 422), and then performs the operation of the other stack tray 422 (or lower stack tray 421). However, the present invention is not limited to this, and includes, for example, a case where both stack trays 421 and 422 are started to operate substantially simultaneously and operated in parallel.

(Tray stop judgment process)
The tray stop determination process is performed when the aligning members 413a and 413b do not move to the retracted position within a predetermined time in the tray switching operation of the flowchart shown in FIG. 15, and the upper stack tray 466 (or the lower stack tray 467) being lifted / lowered. Is stopped so that the upper stack tray 466 (or the lower stack tray 467) does not interfere with the alignment members 413a and 413b.

  In the tray stop determination process, as shown in the flowchart of FIG. 16, a timer for a predetermined time for error check is operated (timer set) under the control of the CPU 1001 (step S1601), and the alignment save process of the alignment members 413a and 413b is performed. (Step S1602) When the predetermined time set in step S1601 has elapsed (time up) (step S1603) and the alignment members 413a and 413b do not move to the retracted position, the upper stack tray 466 (or the lower stack tray 467) ) Is prohibited (step S1604). Then, the CPU 1001 notifies the apparatus main body 11 of the state via the communication IC 1009 (see FIG. 8) (S1605), and ends the tray stop determination process. In this case, an error may be displayed on the display unit (not shown) of the apparatus main body 11.

  The image forming apparatus includes a copying machine, a facsimile machine, a printer, and a complex machine of these. The image forming apparatus of the present invention is not limited to the copying machine described in the above embodiment, but is a facsimile machine. , Printers, and complex machines of these. In addition, the sheet processing apparatus according to the embodiment of the present invention is provided in the apparatus main body of the copying machine and is one of the components of the copying machine. However, the sheet processing apparatus of the present invention is an apparatus of the copying machine. It is provided not only on the main body but also on the main body of the apparatus such as a facsimile, a printer, and a multifunction machine of these.

  Further, the sheet processing apparatus according to the present embodiment is formed separately from the apparatus main body of the copying machine and connected to the apparatus main body of the copying machine, but may be provided in the apparatus main body of the copying machine. Good. The same applies to a facsimile, a printer, and a multifunction machine of these, and may be provided in the apparatus main body. As described above, when the sheet processing apparatus is provided in the main body of a copying machine or the like, the structure can be simplified by using the motor, the plunger, the control unit, and the like. Sheets on which an image can be formed by a copying machine include plain paper, pressure paper, thin resin sheets that are substitutes for plain paper, postcards, and paper for overhead projectors.

1 is a schematic cross-sectional view showing a copying machine as an example of an image forming apparatus including a sheet processing apparatus according to an embodiment of the present invention. 1 is a cross-sectional view illustrating a sheet processing apparatus according to an embodiment of the present invention. The figure which shows the drive part which raises / lowers the upper stage stack tray and the lower stage stack tray in the sheet processing apparatus of embodiment of this invention. The top view of the alignment part which aligns a sheet | seat bundle in the sheet processing apparatus of embodiment of this invention. The top view of the upper stage stack tray in the sheet processing apparatus of embodiment of this invention. FIG. 6 is a diagram illustrating a state when the upper stack tray is at the upper limit and the lower stack tray is at the home position in the sheet processing apparatus according to the embodiment of the present invention. 1 is a block diagram showing a control system of a copier that is an example of an image forming apparatus according to an embodiment of the present invention. 1 is a block diagram showing a control system of a sheet processing apparatus according to an embodiment of the present invention. 6 is a flowchart showing processing at the start of copying in the sheet processing apparatus according to the embodiment of the present invention. 10 is a flowchart showing sheet post-processing control in FIG. 9. 11 is a flowchart showing a tray home position SUB in FIG. 6 is a flowchart showing tray switching operation of the sheet processing apparatus according to the embodiment of the present invention. FIG. 13 is a flowchart showing an alignment saving process in FIG. The flowchart which shows the tray switching process in FIG. 15 is a flowchart showing a tray switching operation SUB in FIG. 6 is a flowchart showing tray stop determination processing of the sheet processing apparatus according to the embodiment of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Control part of reader part 2 Control part of printer part 10 Copying machine 11 Apparatus main body of copying machine 100 Reader part 200 Printer part 300 Automatic document feeder 400 Sheet processing apparatus 400A Apparatus main body of sheet processing apparatus 410 Intermediate tray 413a, 413b Alignment member 421 Upper stack tray 422 Lower stack tray 423, 424 Notch (avoidance part)
461 Home position sensor 490 Alignment part (Alignment means)
1000 Sheet Processing Device Control Unit 1001 CPU

Claims (4)

First sheet stacking means for stacking sheets;
A second sheet stacking means capable of moving up and down, on which sheets are discharged and stacked from the first sheet stacking means;
Sheet discharging means for discharging the sheets stacked on the first sheet stacking means to the second sheet stacking means;
A stacked sheet detecting means for detecting the presence or absence of sheets stacked on the second sheet stacking means;
Tray position detecting means for detecting the position of the second sheet stacking means;
Moving means for moving the second sheet stacking means in the vertical direction;
Control means for operating the moving means to move the second sheet stacking means up and down,
The control means, when discharging the sheets stacked on the first sheet stacking means to the second sheet stacking means, based on the tray position detection information by the tray position detection means. When it is determined that the unit is not at a predetermined reference position, the moving unit is operated to move the second sheet stacking unit to a predetermined reference position.   The sheet processing apparatus according to claim 1, wherein the sheet discharge unit discharges the sheet to the second sheet stacking unit after the second sheet stacking unit has moved to a predetermined reference position. Image forming means for forming an image on a sheet;
The sheet processing apparatus according to claim 1 or 2, wherein a sheet on which an image is formed by the image forming unit is processed.
An image forming apparatus comprising: Image forming means for forming an image on a sheet;
A first sheet stacking unit on which a sheet on which an image is formed by the image forming unit is stacked;
A second sheet stacking means capable of moving up and down, on which sheets are discharged and stacked from the first sheet stacking means;
Sheet discharging means for discharging the sheets stacked on the first sheet stacking means to the second sheet stacking means;
A stacked sheet detecting means for detecting the presence or absence of sheets stacked on the second sheet stacking means;
Tray position detecting means for detecting the position of the second sheet stacking means;
Moving means for moving the second sheet stacking means in the vertical direction;
Control means for operating the moving means to move the second sheet stacking means up and down,
The control means, when discharging the sheets stacked on the first sheet stacking means to the second sheet stacking means, based on the tray position detection information by the tray position detection means. An image forming apparatus, wherein if it is determined that the means is not at a predetermined reference position, the moving means is operated to move the second sheet stacking means to a predetermined reference position.

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