JP4549151B2 - Image forming apparatus - Google Patents

Description

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

  2. Description of the Related Art Conventionally, image forming apparatuses such as copying machines, printers, facsimiles, and composite devices thereof include sheet processing apparatuses that perform processing such as binding processing and punching processing on sheets that have been formed and are discharged from the main body of the image forming apparatus. Some are provided (see Patent Document 1). The image forming apparatus includes a lateral recess having an open side, and a sheet processing apparatus is provided in the lateral recess.

  As such a sheet processing apparatus, a sheet discharged from the image forming apparatus main body is conveyed to a sheet processing unit, and a sheet stacking operation for stacking and aligning the discharged sheets in the sheet processing unit, and a staple for binding the sheets After the processing such as the operation is performed and the processing is finished, the sheet or the sheet bundle (hereinafter referred to as a sheet (bundle)) is discharged to a stack tray (sheet stacking means).

  Further, in general, the sheet processing apparatus is often arranged on the side of the image forming apparatus main body, but the sheet processing apparatus main body does not protrude from the image forming apparatus by being arranged at the upper part of the image forming unit. Such a structure is known that can achieve space saving.

JP 2001-72311 A

  However, in the case of a sheet processing apparatus having only one stack tray on which processed sheets (bundles) are stacked, the main body of a multi-function apparatus having various modes (functions) such as a recent copying machine, printer, and facsimile. Connected to the printer, sheets processed in accordance with modes such as a copying machine, a printer, and a facsimile are mixedly loaded on the same stack tray. For this reason, it is difficult to distinguish (discriminate) from which mode each sheet is output.

  As a method of dealing with such a problem, a plurality of stack trays are arranged in the vertical direction so that they can be individually moved up and down, and the desired stack tray is moved below the sheet discharge port according to the mode, and the stack tray is moved to the stack tray. A configuration in which sheets are stacked is considered.

  However, if a stack tray of a plurality of stages is provided, when the stack tray used in the space where the laterally recessed portion is limited is switched from the upper stack tray to the lower stack tray, the uppermost stack tray is moved to the upper portion in the space. Therefore, there is a problem that it is difficult to take out the sheets stacked on the uppermost stack tray.

An object of the present invention is to provide an image forming apparatus that makes it easy to take out a sheet stacked on the uppermost sheet stacking unit among a plurality of sheet stacking units .

  SUMMARY OF THE INVENTION An object of the present invention is to provide an image forming apparatus in which a sheet processing apparatus that makes it easy to take out sheets stacked on the uppermost sheet stacking means is provided in the apparatus main body so that the user can easily handle the sheets.

In order to achieve the above object, an image forming apparatus according to the present invention includes an image forming unit that forms an image on a sheet, and an image forming sheet discharge unit that discharges a sheet on which an image is formed by the image forming unit. And a sheet processing device that processes a sheet that is provided in the space of the horizontal recess and that is discharged from the image forming sheet discharge unit. The sheet processing device includes: a processed sheet; A plurality of sheet stacking means that can be moved up and down arranged in a vertical direction on which sheets discharged from the processing sheet discharge section are stacked below the upper surface of the laterally recessed portion, and the plurality of sheet stacking means And an elevating unit that counts the elevating distance of the sheet stacking unit. A sheet height detecting means for detecting the height of the sheets stacked on the sheet stacking means, and a selected sheet stacking means out of the plurality of sheet stacking means is discharged from the processing sheet discharge section. Control means for controlling the elevating means based on the count of the elevating distance counting means so that sheets are stacked, and the control means moves the sheet stacking means for stacking sheets from the uppermost sheet stacking means. When switching to a lower sheet stacking unit, a first distance obtained by adding a predetermined interval and the height of the sheets stacked on the uppermost sheet stacking unit detected by the sheet height detecting unit is the processing sheet. When the distance is less than the second distance from the discharge unit to the upper surface of the laterally recessed portion, the uppermost sheet stacked on the upper surface of the laterally recessed portion and the uppermost sheet stacking means. The uppermost sheet stacking unit is lifted and stopped based on the count of the lifting distance counting unit to a position with a predetermined interval between the uppermost sheet stacking unit and the lowermost sheet stacking unit. When the first distance is equal to or greater than the second distance, switching to the sheet stacking unit is stopped from switching from the uppermost sheet stacking unit to the lower sheet stacking unit .

In the image forming apparatus of the present invention, the uppermost sheet stacking unit includes an upper limit detecting unit that detects that the uppermost sheet stacking unit has been raised to the upper surface of the laterally recessed portion , and the control unit is configured so that the uppermost sheet stacking unit is in the lateral direction. The uppermost sheet stacking means is moved to the stacking end position by a distance obtained by subtracting a distance corresponding to the predetermined interval from the distance lowered from the upper surface of the recess to the stacking end position when the stacking of the sheets is completed. It is supposed to be raised from.

Image in forming apparatus, the control means of the present invention, the time for loading the sheet to the lower next sheet stacking means sheet stacking means uppermost, the sheet stacking means of said uppermost sheet stacking of the lower adjacent Until the stacking of the sheet on the means is completed, the sheet is once raised at a position shorter than the distance corresponding to the predetermined interval and above the processing sheet discharge unit.

The elevation distance counting means of the image forming apparatus of the present invention includes an encoder that is rotated by the elevation means and a detection sensor that detects the number of clocks of the encoder.

In the image forming apparatus of the present invention, the control unit opens a predetermined interval between the upper surface of the laterally recessed portion that restricts the rise of the uppermost sheet stacking unit and the sheets stacked on the uppermost sheet stacking unit, Since the uppermost sheet stacking unit is stopped, the sheets stacked on the uppermost sheet stacking unit can be easily taken out.

The image forming apparatus of the present invention, the control means, when to stack the sheets to the lower sheet stacking means sheet stacking means uppermost, a sheet stacking means the uppermost, the stacked sheets on the sheet stacking means lower adjacent Until completion, the sheet is temporarily raised at a position shorter than a predetermined distance and above the sheet discharge unit, so that it is easy to stack sheets on the sheet stacking unit adjacent to the lower side.

In the image forming apparatus according to the present invention, the lifting distance counting means is composed of an encoder that is rotated by the lifting means and a detection sensor that detects the number of clocks of the encoder. The ascending / descending distance can be counted reliably, and the position of the sheet stacking means can be accurately detected.

  The image forming apparatus of the present invention includes a sheet processing apparatus that facilitates taking out the sheets stacked on the uppermost sheet stacking unit in the apparatus main body, so that the user can easily handle the sheets.

Hereinafter, for example, a copying machine as an image forming apparatus according to an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a schematic front view of an image forming apparatus according to an embodiment of the present invention.

  Examples of the image forming apparatus include a copying machine, a facsimile, a printer, and a complex machine of these. Therefore, the image forming apparatus is not limited to a copying machine.

Further, the sheet processing apparatus 400 is not connected only to the apparatus main body 500A of the copying machine 500. The sheet processing apparatus 400 is separate from the apparatus main body 500A of the copying machine 500, but may be incorporated in the apparatus main body 500A.

Further, the sheet processing apparatus includes a stapler unit 420 (see FIGS. 2 and 4) to bind the sheet bundle. However, instead of the stapler unit 420, the sheet processing apparatus includes a punching device to punch holes in the sheet bundle. It may be. Therefore, the sheet processing apparatus is not limited to binding a sheet bundle. Furthermore, a stapler unit and a punching device are not necessarily required. The sheet processing apparatus may have at least a function of aligning the trailing edge of the sheet.

  In the present invention, the upstream end in the sheet conveying direction of the sheet is referred to as the rear end, the downstream end is referred to as the leading end, and the end along the sheet conveying direction is referred to as the side end. Further, the direction intersecting the sheet conveying direction is called the sheet width. Therefore, aligning the rear end of the sheet is referred to as rear end alignment, and aligning the side end is referred to as side end alignment. Aligning the sheet width is called width alignment. When aligning the widths of sheets having the same width, the side edge alignment and the width alignment mean the same alignment.

  The copying machine 500 includes a reader unit 120, an image forming unit such as a printer unit 200, a sheet processing apparatus 400, and the like. An automatic document feeder 300 (hereinafter referred to as “ADF”) for supplying documents one by one onto the platen glass 102 is provided on the upper part of the apparatus main body 500A of the copying machine 500. A sheet processing apparatus 400 that performs post-processing of sheets discharged from the copying machine 500 is connected to the apparatus main body 500A of the copying machine 500.

  The copying machine 500 reads an image of a document supplied by the ADF 300 with the reader unit 120 or reads an image of a document placed on the platen glass 102 of the reader unit 120 by the user with the reader unit 120. In addition to functioning as a copying machine for copying on a sheet by the unit 200, the printer unit 200 receives an image signal sent from an external personal computer and functions as a printer for forming the image signal on a sheet. Yes. Further, the copier 500 transmits an image signal read by the reader unit 120 to another facsimile, or receives a facsimile signal from another facsimile by the printer unit 200, and prints an image on a sheet based on the signal. It also functions as a facsimile machine to be formed.

  When the copying machine 500 reads a document image to form an image, first, a document (not shown) loaded on an automatic document feeder (ADF) 300 is sequentially transferred one by one by the ADF 300 to the reader unit 120. It is conveyed on the platen glass 102.

  Next, when the document is conveyed to a predetermined position on the platen glass 102, the lamp 103 of the reader unit 120 is turned on, and the scanner unit 104 is moved to irradiate the document. Then, the reflected light from the original is input to the CCD image sensor unit 109 through the mirrors 105, 106, 107 and the lens 108, and electrical processing such as photoelectric conversion is performed in the CCD image sensor unit 109, and normal digital processing is performed. Is given.

  Next, the image signal subjected to the electrical processing in this way is converted into a modulated optical signal by the exposure control unit 201 of the printer 200. The exposure control unit 201 irradiates the photosensitive drum 202 with an optical signal as a laser beam. A latent image is formed on the photosensitive drum 202 by the irradiation light. This latent image is developed by the developing device 203 and becomes a toner image on the photosensitive drum 202.

  Next, the sheet S is conveyed from the sheet cassettes 204 and 205 in synchronization with the leading edge of the toner image, and the toner image is transferred to the sheet S by the transfer unit 206. The toner image transferred to the sheet S is fixed by the fixing unit 207. Thereafter, the sheet S is discharged from the sheet discharge unit 208 to the outside of the apparatus main body 500A.

  Next, after the image formation is completed as described above, the sheet S discharged from the sheet discharge unit 208 is conveyed to the sheet processing apparatus 400, and is sorted and bound according to an operation mode designated in advance by the sheet processing apparatus 400. Are stacked on a stack tray (a lower tray stack tray 421 or an upper bin stack tray 422), which is a desired sheet stacking unit. The upper tray stack tray 422 is an example of the uppermost sheet stacking means. A stack tray 421 in the lower bin is an example of a sheet stacking unit adjacent to the lower side.

  Next, the sheet processing apparatus 400 will be described.

  As shown in FIG. 1, the sheet processing apparatus 400 protrudes from the apparatus main body 500A of the copying machine into, for example, a space SP, which is a laterally recessed portion that is open to the outside on the side of the apparatus main body 500A of the copying machine 500. It is stored without. The space SP is formed by a stepped portion of the apparatus main body 500A and the bottom surface 120a of the reader unit 120.

  In addition to the sorting function for sorting sheets, the sheet processing apparatus 400 includes, for example, a stapling function that is a binding operation by the stapler unit 420 illustrated in FIG. As shown in FIG. 2, the sheet processing apparatus includes a processing tray 410 for processing sheets S sequentially discharged from the apparatus main body 500A (see FIG. 1) of the copier 500, and a sheet processed on the processing tray 410. A stack tray (lower bin) 421 and a stack tray (upper bin) 422 for finally stacking the bundles are provided, and a sheet bundle corresponding to the number of documents is formed on the processing tray 410, and each sheet bundle is formed. The stack tray (lower bin) 421 or the stack tray (upper bin) 422 can be discharged and stacked.

  The sheet processing apparatus 400 has an unconventional configuration in which a plurality (two in the sheet processing apparatus 400 of the present embodiment) of stack trays 421 and 422 can be moved up and down independently. Further, the sheet processing apparatus 400 is not limited to a simple copy job, but can separate and stack the stack trays 421 and 422 in order to output sheets away from an image forming apparatus such as a printer or a facsimile. It also has a structure that can contribute greatly.

  A reader unit 120 and an automatic document feeder (ADF) 300 are provided at the upper part of the apparatus main body 500A of the copying machine 500 shown in FIG. 1, but a sheet processing apparatus 400 is provided instead of these. Also good. As described above, by providing the sheet processing apparatus 400 in the installation space of the apparatus main body, the installation space of the copying machine can be reduced.

  Next, the configuration of the sheet processing apparatus 400 will be described.

  In FIG. 2, a sheet receiving unit 401 receives the sheet S discharged from the apparatus main body 500A of the copying machine. After the sheet S received by the sheet receiving unit 401 is detected by the entrance sensor 403, the sheet S is transported and stacked on the processing tray 410 by the transport roller 405 and the offset roller 407 (see FIG. 3). The processing tray 410 is provided in the sheet processing unit 400B that processes sheets. The sheets S stacked on the processing tray 410 are detected by a sheet bundle discharge sensor 415 shown in FIG.

  The offset roller 407 is configured by a cylindrical member. The cylindrical member is formed of an elastic body whose outer peripheral portion has elasticity close to rubber, such as rubber or foam. The offset roller 407 is supported by the offset roller holder 406. The offset roller holder 406 is rotated in the vertical direction by a pickup solenoid 433 with an offset shaft 511 shown in FIG. 4 as a fulcrum. That is, the offset roller 407 is raised and lowered via the solenoid arm 512, the lever holder 513, the separation lever 514, and the offset roller holder 406 when the pickup solenoid 433 is turned on / off.

  Further, when the sheet S is discharged to the processing tray 410, the offset roller 407 prevents the discharge of the sheet S via the solenoid arm 512, the lever holder 513, the separation lever 514, and the offset roller holder 406 when the pickup solenoid 433 is turned on. Not to move to an upper position. Thus, the sheet S is discharged and stacked on the processing tray 410 without being obstructed by the offset roller 407.

  Further, the offset roller 407 is passed through a timing belt 523, a roller gear 524, an idler gear 525, an offset gear 526, an offset pulley 527, and a timing belt 522 by a transport motor 431 capable of rotating forward and backward to drive the transport roller 405 shown in FIG. It is designed to rotate. When the transport motor 431 rotates, the offset roller 407 rotates in the transport direction by the amount corresponding to the rotation amount of the transport motor 431 (forward rotation), or rotates in the direction opposite to the transport direction (hereinafter referred to as reverse rotation). ing.

  The pickup solenoid 433 is turned off when the CPU 100, which will be described later with reference to FIG. 2, receives an off signal from the inlet sensor 403 through which the rear end of the sheet passes through the inlet sensor 403. When the pickup solenoid 433 is turned off, the offset roller 407 descends by its own weight while rotating in the sheet conveying direction and landed (contacts) on the sheet, and after the sheet has been conveyed downstream in the sheet conveying direction for a predetermined time. Further, when a predetermined time elapses, the sheet is reversed and returned to the upstream side in the sheet conveying direction.

  As described above, the offset roller 407 is reversely rotated so that the rear end (upstream end) of the sheet abuts against the sheet rear end stopper 411 to align the rear end of the sheet S. The sheet trailing edge stopper 411 is erected on the upstream end of the processing tray 410 in the conveyance direction so as to receive the sheet trailing edge. Therefore, the trailing edge alignment of the sheet is performed by the offset roller 407 abutting the trailing edge of the sheet against the sheet trailing edge stopper 411.

  In FIG. 4, the width-direction positioning wall 416 receives the side edge of the sheet and can align the side edge of the sheet. The stapler unit 420 is disposed in the vicinity of the width direction positioning wall 416 and binds the sheet bundle formed on the processing tray 410.

  The offset roller 407 moves in the width direction of the sheet via the offset motor gear 432a, the offset pinion 516, and the offset rack 515 by driving the offset motor 432 capable of forward and reverse rotation so as to approach and separate from the width direction positioning wall 416. It has become.

  The sheet abutted against the sheet trailing edge stopper 411 and aligned at the trailing edge is dragged in the direction of the width direction positioning wall 416 by the frictional force of the offset roller 407 as the offset roller 407 approaches the width direction positioning wall 416. While being moved as described above, the curl is corrected by the sheet press 510 and brought into contact with the width direction positioning wall 416 so that the side edges are aligned. After the sheet S hits the width direction positioning wall 416, the offset roller 407 is moved by a predetermined amount toward the width direction positioning wall 416 while being slightly slid on the sheet.

  Accordingly, since the sheet processing apparatus 400 includes the offset roller 407 that performs the above-described operation, the sheet discharged onto the processing tray 410 is offset to rotate in the sheet conveyance direction as shown in FIG. After being conveyed to the stack trays 421 and 422 (downstream in the sheet conveyance direction) by the roller 407, the sheet is conveyed upstream by the reverse rotation of the offset roller 407 as shown in FIG. The rear end is aligned.

  The sheet having the rear end aligned is then dragged by moving the offset roller 407 contacting the sheet along the offset shaft 511 toward the width direction positioning wall 416 as shown in FIG. 5C. Abutting against the direction positioning wall 416, side end alignment is performed.

  The offset roller 407 shown in FIGS. 5 to 7 and FIG. 24 is located between a pair of offset roller holders 406, unlike the offset roller 407 shown in FIG. Is merely a design difference, and has the same configuration and operation as the offset roller 407 shown in FIG.

  4 and 5, the sheet clamp member 412 sandwiches the rear end portion of the aligned sheet S with a pair of claws 412c and 412d by the urging force of the urging portion 560 (see FIG. 4). . The upper claw 412c opens and closes with respect to the lower claw 412d. After the side edge alignment of the sheet S is performed, the sheet clamp member 412 is aligned at the side edge when the offset roller 407 is lifted by the pickup solenoid 433 (see FIG. 4) as shown in FIG. The sheet S is sandwiched as shown in FIG.

  By sandwiching the sheet S, the sheet clamp member 412 prevents the sheet S previously discharged (conveyed) from the processing tray 410 from being conveyed to the downstream side by the sequentially fed sheets S. It is supposed to be.

  Further, the sheet clamp member 412 is pivoted upward and opened as shown in FIG. 7A so that the sheet S can be received when the offset roller 407 is reversely rotated. Further, as shown in FIG. 7B, the sheet clamp member 412 does not become a load of movement of the sheet S even when the offset roller 407 moves the side end aligned sheet toward the width direction positioning wall 416. It pivots upward and is open.

  In FIG. 9, the sheet bundle discharging member 413 is configured to discharge the processed sheet bundle to the stack tray (lower bin) 421 or the stack tray (upper bin) 422. The sheet bundle discharge member 413 includes a claw 412c on the upper side of the sheet clamp member 412 so as to be rotatable. The sheet bundle discharging member 413 holds the aligned sheet bundle or the stapled sheet bundle after being aligned by the sheet clamp member 412, as shown in FIG. It moves toward a stack tray (lower bin) 421 or a stack tray (upper bin) 422 provided on the downstream side.

  When the sheet bundle discharge member 413 reaches the front end of the processing tray 410 which is the sheet discharge position indicated by the solid line in FIG. 9, the sheet bundle discharge member 413 stops on the stack trays 421 and 422 while holding the sheet bundle SA by the sheet clamp member 412. . The sheet bundle discharge member 413 returns to the sheet trailing edge stopper 411 as the sheet clamp member 412 opens the sheet bundle SA. The released sheet bundle SA falls onto the trays 421 and 422.

  As described above, in the sheet processing apparatus 400 according to the present embodiment, the sheet bundle SA is transported to the stack trays 421 and 422 by the sheet clamp member 412 and dropped. Therefore, conventionally, the stack tray is inclined by about 30 degrees. However, the sheet bundle can be stacked in a stable state at an angle smaller than that of about 9 degrees, and can be installed in a space whose height direction is limited.

  Note that the sheet bundle SA discharged and stacked on the stack trays 421 and 422 is pressed against the stack trays 421 and 422 by a pressing member 421A shown in FIG. As described above, in the sheet processing apparatus 400, since the pressing member 421A is configured to press the sheet bundle SA against the stack trays 421 and 422, it is possible not only to prevent a decrease in the stacking amount due to the curling of the sheets, but also to be stacked. It is also possible to prevent a decrease in stacking performance, such as the preceding sheet being pushed by the succeeding sheet and the stacking position of the preceding sheet being shifted. As a result, the sheet processing apparatus 400 achieves stable stacking performance in a limited space at a small substantially horizontal angle as in the present embodiment without providing the conventional stack tray angle inclined about 30 degrees. can do.

  Here, a pin A553a and a pin B554a suspended from a slide gear A553 and a slide gear B554 that rotate via a belt 551 and a pulley gear 552 by driving the sheet bundle discharge motor 430 shown in FIG. The sheet bundle discharge member 413 is moved by moving in a guide slit (not shown) formed in the sheet bundle discharge member 413 while rotating integrally with the gear B554.

  With this configuration, the sheet bundle discharge member 413 discharges the sheet to the stack tray (1 lower bin) 421 or the stack tray (2 upper bin) 422 by the sheet bundle discharge motor 430 (FIG. 8 ( b)), and a home position in the vicinity of the seat trailing edge stopper 411 (see FIGS. 2 to 7), reciprocates along the slide rail 555 (see FIGS. 8A and 8B). . The sheet bundle discharge member 413 is normally fixed at the home position by excitation of the sheet bundle discharge motor 430.

  In FIG. 10, the clamp solenoid 434 rotates the sheet clamp member 412. The clamp solenoid 434 is turned on when the offset roller 407 conveys the sheet downstream and then stops rotating, or when the offset roller 407 moves in the width direction, and is provided in the lever 434a and the sheet clamp member 412. The upper claw 412c of the sheet clamp member is rotated upward via the release lever portion 412a.

  Note that the holding member 421A shown in FIG. 2 is powered via a press member 556, a lever member 557, and a coil spring 558 by a cam B554b installed at the lower portion of the slide gear B554 as shown in FIG. Is transmitted so as to rotate in the vertical direction. Further, as shown in FIG. 11B, the pressing member 421A is moved away from the sheet stacking surface of the stack trays 421 and 422 by the return coil spring 559 as shown in FIG. It has become.

  The pressing member 421A is configured such that the sheet bundle discharge member 413 discharges the sheet bundle to the stack trays 421 and 422 by the rotation of the slide gear A553 and the slide gear B554 by the rotation of the sheet bundle discharge motor 430, and then the press member 556 by the cam B554b. When the pressing is released, the return coil spring 559 allows the sheet bundle to fall onto the stack trays 421 and 422 with respect to the sheet stacking surface.

  Thereafter, while the sheet bundle falls to the stack trays 421 and 422 and the sheet bundle discharge member 413 returns to the sheet rear end stopper 411, the cam B554b below the slide gear B554 operates the press member 556, and the lever member 557, The holding member 421A is rotated via the coil spring 558, and the sheet bundle is held by the holding member 421A.

  In the meantime, the sheet processing apparatus 400 according to the present embodiment moves the sheet S in the width direction as described above, performs the side edge alignment, and then corrects the deviation in the trailing edge alignment of the sheet. The rear end alignment is performed again by reversing the rotation. As a result, the sheet processing apparatus 400 according to the present embodiment can perform highly accurate rear-end alignment and side-end alignment of sheets. When the alignment process for the designated number of sheets is completed, the clamp solenoid 434 closes the sheet clamp member 412 and holds the sheet bundle.

  Next, FIG. 12 is a diagram of an elevating device 509 that is an elevating means for elevating and lowering the stack tray. The lifting device 509 is provided for each tray. The lifting device 509 is provided on the lifting frame 548. The elevating frame 548 is provided with a stack tray. Based on FIG. 12, for example, the raising / lowering operation of the stack tray 421 in the lower bin will be described. First, the rotational force of the stack tray lifting / lowering motor 530 is transmitted to the worm gear a 534 and the worm gear b 535 at both ends of the rotating shaft via the belt 531, the pulley 532, and the rotating shaft 533.

  The rotational force of the worm gear a534 is transmitted from the worm wheel a536 and the gear 1a537 formed integrally with the worm wheel a536 to the gear 2a538, and further transmitted to the gear 3a539 formed integrally with the gear 2a538.

  Similarly, the rotational force of the worm gear b535 is transmitted from the worm wheel b541 and the gear 1b542 formed integrally with the worm wheel b541 to the gear 2b544, and further to the gear 3b543 formed integrally with the gear 2b544.

  Finally, the stack tray 421 moves up and down as the gears 3a539 and 3a543 roll on the fixed rack a540 and rack b545.

  The stack bin 422 in the upper bin is also provided with an elevating device 509 similar to the stack tray 421 in the lower bin, and moves up and down in the same manner as the stack tray 421 in the lower bin.

  In FIG. 12, the clutch a 560 rotates in conjunction with the pulley 532. A coil spring 561 is wound around the clutch a560. The opposite side of the coil spring 561 is wound around the clutch b562. Further, a pin 563 that is press-fitted into the rotary shaft 533 is engaged with the groove of the clutch b562. With such a configuration, a desired rotational torque of the stack tray lifting / lowering motor 530 is transmitted to the rotating shaft 533, and the rotational force is transmitted to the worm gear a534 and the worm gear b535 at both ends of the rotating shaft 533.

  By the way, the sheet processing apparatus 400 of the present embodiment includes stack trays 421 and 422 that can be moved up and down in the sheet stacking space diagram SP1, and detects the movement of the stack tray 422 in the upper bin as will be described later. A clock disk 562a and a stack tray clock sensor 564 for calculating the moving distance of 422 are provided.

Instead of the clock disc 562a and the stack tray clock sensor 564, using a stepper motor to the stack tray lift motor 530, and counts the pulses generated by the stepping motor, even by detecting the position of the stack tray 422 of the upper bin Good.

  Next, a tray switching operation between the stack bin 421 in the lower bin and the stack tray 422 in the upper bin will be described.

  The stack tray (lower bin) 421 and the stack tray (upper bin) 422 are respectively moved by the gear 3a539 and the gear 3a543 rolling on the fixed rack a540 and rack b545 by the stack tray lifting / lowering motor 530 shown in FIG. It can be moved up and down independently. The movement amount of the stack trays 421 and 422 is taken into the CPU 100 by the clock output from the stack tray clock sensor 564.

  The processed stack discharged by the sheet bundle discharge member 413 is received by raising and lowering the selected stack tray out of the two trays of the stack tray (lower bin) 421 and the stack tray (upper bin) 422. be able to. Further, the stack tray can be selected for each sheet by serial communication from the copying machine main body 500A, and the lower tray stack tray 421 and the upper bin stack tray 422 can be switched by the instruction. ing.

  Normally, a plurality of (N) stack trays (two in this embodiment) are made to wait while sandwiching, for example, a sheet discharge port 400A which is a sheet discharge portion of sheets discharged by the sheet bundle discharge member. In the state of FIG. 2, a space is provided below the stack tray (lower bin) 421, so that not only can a large number of sheets be stacked, but also the stack tray (upper bin) 422 is retracted depending on the contents described later. Since the upper and lower bins can be switched and stacked on the upper bin, more sheets can be stacked.

  Here, when the stack tray (lower bin) 421 is in a position where the sheet can be received and the stack tray (upper bin) 422 is retracted to the upper side (FIG. 13A), the stack tray (upper bin) ) The movement of 422 to a position where the sheet below the sheet discharge port 400A can be received will be described.

  Below the stack tray (lower bin) 421 is provided a lower limit detection sensor 546 that detects the lower limit of the internal movement range of the copying machine main body 500A. First, the stack tray (lower bin) 421 is lowered to a position where it is detected by the lower limit detection sensor 546. At this time, the pressing member 421A moves to the retracted position indicated by the solid line (FIG. 13B).

  Next, when the pickup solenoid 433 shown in FIG. 4 is turned on and the electromagnetic clutch 517 is turned on while the offset roller 407 is moved to the upper standby position via the offset roller holder 406, the drive of the transport motor 431 is connected. Then, by rotating the transport motor 431 by a predetermined amount, the shutter 521 is lowered via the gear portion 517a, the idler gear 518, the cam gear 519, and the shutter lever 520 of the electromagnetic clutch 517 as shown in FIG. .

Then, the shutter 521 descends in this way and closes the sheet discharge port 400A of the processing tray 410, so that the shutter 521 forms a guide surface at the rear end of the sheet (FIG. 15A). As a result, in the sheet processing apparatus 400 of the present embodiment, when the stack tray (upper bin) 422 is moved up and down, sheets already stacked on the stack tray (upper bin) 422 do not flow back into the processing tray 410 and enter. It is like that.

  When the lowering of the shutter 521 is completed, the stack tray (upper bin) 422 starts to lower and stops at a position where it passes through the pressing member 421A (FIG. 15B). Thereafter, the shutter 521 moves up and stops at a desired position. Then, the holding member 421A that has been retracted rotates to a position where the sheet can be pressed. The stack tray (upper bin) 422 rises to a position for receiving a sheet and stops (FIG. 16A). Thereafter, the stack tray (upper bin) 422 can receive sheets in the same manner as the stack tray (lower bin) 421.

Then, the stack tray (upper bin) 422 is are in a position capable of receiving a sheet from the state stack tray (bottom bin) 421 is retracted to the lower side (FIG. 16 (a)), the stack tray (lower The tray switching operation in which the bin 421 moves up and down to a position for receiving a sheet will be described.

  In this case, first, the CPU 100 to be described later returns the pressing member 421A to the retracted position and lowers the shutter 521 so that the sheets already stacked on the stack tray 422 of the upper bin are loaded from the sheet discharge port 400A to the processing tray 410. In such a case, the reverse flow is prevented (FIG. 16 (b)).

When the stack tray 422 in the upper bin is at a position where the sheet can be received, the CPU 100 starts the movement amount counter 111. The stack tray 422 starts to rise, the clocks from the clock disk 562a and the stack tray clock sensor 564 are taken into the CPU 100, and the movement amount counter 111 is counted up. The CPU 100 calculates the movement distance of the stack tray 422 by the movement amount counter 111 and stores it in the RAM 121 or the like. The stack tray 422 passes through the sheet discharge port 400A and rises to a space SPU (see FIG. 1) provided above the sheet discharge port 400A.

The clock disk 562a, the stack tray clock sensor 564, and the movement amount counter 111 are an example of a lifting distance counting unit.

  Next, the shutter 521 moves up to a desired position, opens the sheet discharge port 400A, and then stops (FIG. 17B). Next, the holding member 421A that has been retracted moves to a position where the sheet can be pressed. Then, the stack tray (lower bin) 421 rises to a position where the sheet is received and stops (FIG. 13A). As a result, the stack tray (lower bin) 421 can receive sheets.

  FIG. 19 is a block diagram illustrating a configuration of a control unit of the sheet processing apparatus 400. For example, the CPU 100 as a control means has a ROM 110 therein, and the ROM 110 stores a control program corresponding to control procedures shown in FIGS. 20, 21, and 23 described later. The CPU 110 controls each unit while reading this program.

  The CPU 100 has a built-in RAM 121 in which work data and input data are stored, and controls each unit based on the data stored in the RAM 121. Further, the CPU 100 has a movement amount counter 111 that counts the movement (lifting / lowering) amount of the stack tray.

  Sensors such as an inlet sensor 403, a stack tray clock sensor 564, a lower limit detection sensor 546, and an upper limit detection sensor 547 are connected to the input port of the CPU 100. Based on the state of these sensors, the CPU 100 executes a control program stored in the ROM 110 and corresponding to the control procedure shown in FIGS. 20, 21, and 23, and the conveyance motor 431 and the offset motor 432 connected to the output port. In addition, a load such as a sheet bundle discharging motor 430, a stack tray raising / lowering motor 530, a pickup solenoid 433, a solenoid such as a clamp solenoid 434, and a display unit of the operation panel 580 are controlled.

  In addition, the CPU 100 includes a serial interface unit (I / O) 130, exchanges control data with the control unit 140 of the apparatus main body 500 </ b> A of the copier 500, and passes through the serial interface unit (I / O) 130. The respective units are controlled based on the control data sent from the control unit 140 of the copying machine main body 500A.

  Since the copying machine main body 500A knows the size of the sheet discharged from the sheet discharging unit 208, the CPU 100 of the sheet processing apparatus 400 comprising a microcomputer system controls the control unit 140 of the copying machine main body 500A. , The size of the sheet inserted on the processing tray 410 can be grasped.

  Therefore, each time the sheet S is discharged (conveyed) from the copying machine main body 500A, the control unit (CPU 100) of the sheet processing apparatus 400 grasps the size of the sheet S and controls the offset motor 432. The amount of movement in the width direction 407 can be controlled. As a result, the offset roller 407 moves by an amount corresponding to the size of the sheet S inserted on the processing tray 410, and the side portion of the sheet can be surely brought into contact with the positioning wall 416 (see FIG. 4). it can.

  In the sheet processing apparatus 400 according to the present embodiment, since the sheet bundle stacked on the stack tray 421 constitutes a part of the processing tray 410, when the sheet bundle SA is discharged from the processing tray 410, the stack is stacked. The tray 421 is lowered by the stack tray lifting / lowering motor 530 (see FIG. 12) until the uppermost surface of the stacked sheet bundle substantially coincides with the processing tray 410.

  Next, the operation of the sheet processing apparatus according to the present embodiment will be described with reference to the block diagrams of FIGS. 1 to 18, 22, and 24, the control block diagram of FIG. 19, and the flowcharts of FIGS. This will be explained based on.

The distance L1 from the sheet discharge port 400A (see FIG. 24A) to the uppermost part in the main body (in this embodiment, the bottom surface 120a of the reader unit 120 ) depends on the dimensions of the mechanism, but is stored in the RAM 121 or the like in advance. It is. A specified value that is preloaded in the ROM 110 may be used as L1.

When the sheet is discharged to the stack tray 422 in the upper bin (S600), the CPU 100 controls the stack tray 422 to move up and down. The CPU 100 raises the stack tray 422 of the upper bin until it is detected by the upper limit detection sensor 547, and then lowers it according to the discharge of the sheet (S601 and S611 of the height detection subroutine (SUB)). At that time, the CPU 100 counts a specific pulse by the stack tray clock sensor 564 and stops the stack tray 422 in the upper bin (S613). The count number at that time is A. The upper limit detection sensor 547 is an example of a detection unit that detects that the stack tray 422 of the upper bin has risen to, for example, the bottom surface 120 a that is the rise restriction wall of the reader unit 120.

  Note that there is a method for calculating the count number A without raising the stack tray 422 up to the upper limit detection sensor. That is, the CPU 100 counts the height H1 at which the stack tray 422 descends from the position where the sheet discharge is completed (the position shown in FIG. 24B) to a predetermined position detected by the sensor 546a. The height H2 is counted by raising the sheet stacked on the tray 422 until it is detected by a sensor 546b that detects that the sheet has been raised to the sheet discharge port 400A. Then, the CPU 100 obtains the sheet height C (= H2−H1). As a result, the CPU 100 can obtain the count number A by (C + L1).

  When the discharge of the sheet is completed, the CPU 100 raises the stack tray 422 of the upper bin (S614). The CPU 100 raises the stack tray 422 until the uppermost sheet S1 is turned on by the upper limit detection sensor 547 among the sheets stacked on the stack tray 422 in the upper bin (S615). Thereafter, the CPU 100 lowers the stack tray 422 of the upper bin by the amount counted by the pulse count D so that a predetermined gap (interval) D is generated between the bottom surface 120a of the reader unit 120 and the uppermost sheet S1. (S616).

  Note that the CPU 100 places a predetermined gap (interval) D between the uppermost sheet S1 and the bottom surface 120a of the reader unit 120 in the stack tray 422 of the upper bin at the position shown in FIG. The pulse count may be increased by B (= A−D).

  As described above, in the sheet stacking apparatus 400 according to the present embodiment, a predetermined gap (interval) D that allows a user to easily take out a sheet is formed between the bottom surface 120a of the reader unit 120 and the uppermost sheet S1. Therefore, the sheet can be taken out without damaging the sheet.

  The height of the sheets stacked on the stack tray 422 of the upper bin is C (= A−L1).

As shown in FIG. 24A, when the stack bin 422 of the upper bin rises, when (D + C) ≧ L1, the sheet discharge port 400A is opened by the stack tray 422 of the upper bin or the sheet on the stack tray 422. Since it is blocked, the sheet cannot be discharged to the stack tray 421 in the lower bin. Therefore , the CPU 100 does not perform the switching control of the stack tray from the stack tray 422 in the upper bin to the stack tray 421 in the lower bin (NO in S602), and ends the sheet reception. At the same time, the CPU 100 notifies this to the control unit 140 of the main body 500A through communication. Further, the CPU 100 displays on the display unit of the operation panel 580 (see FIG. 1) that sheets are not stacked on the stack tray 421 in the lower bin.

  When (D + C) <L1, the stack tray 422 in the upper bin is above the sheet discharge port 400A and does not block the sheet discharge port 400A, so that sheets are stacked on the stack tray 421 in the lower bin. Can do. Therefore, the CPU 100 performs an operation of switching the sheet stacking operation from the stack tray 422 in the upper bin to the stack tray 421 in the lower bin (YES in S602).

Then, the CPU 100 determines whether or not the copying operation is performed in the apparatus main body 500A (S603). When the copying operation is being performed (YES in S603), the CPU 100 raises the stack tray 422 in the upper bin and narrows the gap (interval) D in order to easily discharge the sheet to the stack tray 421 in the lower bin. The distance between the stack bin 422 in the upper bin and the stack tray 421 in the lower bin is increased. When the stacking of sheets on the stack tray 421 in the lower bin ends, the CPU 100 lowers the stack tray 422 in the upper bin so that the gap (interval) D is generated, and ends a series of processes.

In S603, when the copying operation is not performed in the apparatus main body 500A (NO in S603), the CPU 100 stops the stack tray 422 of the upper bin at a position where a gap larger than the gap (interval) D is generated.

  A plurality of stack trays 421 and 422 can be independently lifted and lowered in the sheet processing apparatus 400 stored in the space SP (see FIG. 1) formed in the side portion of the apparatus main body 500A of the copying machine in this manner. By enabling the sheets to be selectively stacked on the stack trays 421 and 422, even when the sheet processing apparatus 400 is incorporated in a composite printer having a mode such as a copying machine, a printer, or a facsimile, it can be saved. It is possible to easily distinguish between the sheets that are available and in which mode the sheets are output.

  In addition, sorting and stacking according to modes such as copy, printer, and facsimile becomes possible, and an apparatus optimal for office needs can be provided.

  Further, by moving the stack tray (upper bin) 422 above the sheet discharge port 400A, the stack trays 421 and 422 can be moved up and down in the space SP formed in the side portion of the copying machine main body 500A. The space SPU above the sheet discharge port 400A in the sheet stacking space SP1 to be used can be used as a sheet stacking space, whereby a large number of sheets can be stacked.

  When the space SPU above the sheet discharge port 400A is used as a sheet stacking space, it is preferable to provide the sheet discharge port 400A at a substantially center in the height direction of the sheet stacking space SP1. By providing the sheet discharge port 400A at such a position, a large amount of sheets can be stacked using the sheet stacking space SP1 efficiently.

  In the description so far, the case where two stack trays are provided has been described. However, a plurality (N) of stack trays are provided, and a space SPU above the sheet discharge port 400A is provided as a plurality (N) of stack trays. When (n-1) stack trays are movable, a limited number of sheet stacking spaces SP1 can be efficiently used to stack a large number of sheets.

  Further, if the sheet discharge port 400A is used as a common sheet discharge port in a mode such as a copying machine, a printer, and a facsimile, and sheets are selectively discharged from the common sheet discharge port 400A to a plurality of stack trays, space saving is achieved. And the height dimension can be suppressed.

  In addition, when the sheet discharge port 400A is a common sheet discharge port and the sheets are discharged from the sheet discharge port 400A to the stack tray by one sheet bundle discharge member 413, the configuration can be simplified. Cost can also be reduced.

  As shown in FIG. 18A, a sub-tray 421a is housed in the downstream end of the stack trays 421 and 422 in the sheet discharge direction so that it can be pulled out. The stack trays 421 and 422 are arranged so as not to protrude from the apparatus main body 500A of the copying machine, and A4, B5, letter size (or smaller size sheets) having a high user frequency can be stacked as they are. ing.

  On the other hand, as shown in FIGS. 18 (a) and 18 (b), the stack trays 421 and 422 are stacked as needed when large sheets such as A3 size, B4 size, and legal size are stacked. , 422 can be pulled out from the sub-tray 421a. Further, the stack trays 421 and 422 have another sub-tray 421b slidable on the sub-tray 421a, and the two sub-trays 421a and 421b can be pulled out according to the sheet size as shown in FIG. It is like that. For this reason, the stack trays 421 and 422 can stack sheets satisfactorily.

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

  First, when an image forming operation is started by the copying machine main body 500A, the CPU 100 (see FIG. 19) of the sheet processing apparatus 400 checks whether a sheet discharge signal is received from the copying machine main body 500A. (S100). If a sheet discharge signal is received (YES in S100), the pickup solenoid 433 is turned on (S110), and the offset roller 407 supported by the offset roller holder 406 is pulled up.

  Next, the CPU 100 turns on the conveyance motor 431 (S120) so that the conveyance roller 405 installed in the middle of the sheet discharge path can convey the sheet in the same direction as the sheet discharge direction of the copying machine main body 500A. To do. Here, the entrance sensor 403 is turned on at the leading end of the first sheet (YES in S130), and reaches the conveying roller 405. When the sheet is separated from the sheet discharge unit 208 (see FIG. 1) of the copying machine main body 500A by the conveying roller 405 (YES in S140), the sheet is transferred to the sheet processing apparatus.

  Next, when the CPU 100 conveys the sheet to the processing tray 410 by the conveyance roller 405 and receives an OFF signal from the inlet sensor 403 through which the rear end of the sheet passes through the inlet sensor 403, the CPU 100 turns off the pickup solenoid 433 (S150). The offset roller 407 is landed on the sheet by its own weight. Thereafter, as shown in FIG. 5A, the CPU 100 causes the offset roller 407 to convey the sheet S to a predetermined position (S160). Then, when the sheet S is conveyed to a predetermined position (YES in S160), the CPU 100 stops the rotation of the conveyance motor 431 (S170) and stops the conveyance of the sheet S.

  Next, the CPU 100 turns on the clamp solenoid 434 when the rotation of the offset roller 407 stops (S180), and as shown in FIG. 5B, the sheet clamp installed near the sheet trailing edge stopper 411. Open member 412. Thereafter, the CPU 100 rotates the conveyance motor 431 in the direction opposite to the conveyance direction, pulls back the sheet S by the offset roller 407 (S190), and abuts the sheet trailing edge against the sheet trailing edge stopper 411.

  Note that the rotation amount of the offset roller 407 when the trailing edge of the sheet abuts against the trailing edge stopper 411 takes into account the skew of the sheet S that occurs when the sheet S is fed from the copying machine main body 500A. Is controlled by the CPU 100 so that it can be transported slightly more than the distance from the point of stopping and switching back to the sheet trailing edge stopper 411. That is, the CPU 100 reverses the offset roller 407 for a predetermined time even after the sheet S has been conveyed by a distance that causes the sheet S to contact the sheet trailing edge stopper 411.

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

  Next, the CPU 100 checks the sheet size to be discharged based on the size information from the apparatus main body 500A of the copying machine (S200), and discharges the offset movement amount according to the size of the discharged sheet S, that is, discharged onto the processing tray 410. The movement distance in the width direction of the sheet S required to press the sheet S against the width direction positioning wall 416 is calculated (S210).

  Then, the CPU 100 causes the offset roller 407 to be offset by the offset motor 432 as shown in FIG. 5C to the width direction positioning wall 416 via the offset pinion 516 (see FIG. 4) and the offset rack 515 (S220). . Here, when the offset roller 407 moves, the sheet S in contact with the offset roller 407 moves together with the offset roller 407 toward the width direction positioning wall 416 by the frictional force of the offset roller 407. At this time, the sheet clamp member 412 is opened as shown in FIG. 7B so as not to be a load of movement of the sheet S.

  Next, as shown in FIG. 5C, the offset roller 407 moves while stopping while slightly sliding on the sheet S after abutting the sheet S against the width direction positioning wall 416. Thereafter, the CPU 100 reversely reverses the offset roller 407 and pulls back the sheet S in order to correct misalignment of the trailing edge of the sheet caused by the offset movement of the sheet (S230). As a result, the rear end of the first sheet S is realigned, and the sheet alignment is completed.

  Next, when the alignment of the first sheet S is completed in this way, the CPU 100 turns on the pickup solenoid 433 (S240), and then lifts the offset roller 407 as shown in FIG. 6A. Then, the clamp solenoid 434 is turned off (S250). As a result, the sheet clamp member 412 is closed as shown in FIG. 6B, and the aligned sheet S is held by the sheet clamp member 412. As a result, it is possible to prevent the sheet S discharged first from being conveyed to the downstream side in the sheet conveying direction by the subsequent sheet discharged next.

  Next, as shown in FIG. 6B, the offset roller 407 is moved back to the home position by the offset motor 432 via the offset pinion 516 (see FIG. 4) and the offset rack 515 while being lifted (see FIG. 6B). S260).

  The CPU 100 checks whether or not the sheet S accommodated on the processing tray 410 is the last sheet corresponding to the last page of the copied document (S270), and based on the information sent from the copying machine main body 500A. If it is determined that the sheet S is not the final sheet S (NO in S270), the process returns to S100, and a sheet discharge signal sent from the apparatus main body 500A of the copier is received, and the final sheet S is transferred to the processing tray 410. The above-described flow of loading is repeated.

  Thereby, the CPU 100 of the sheet processing apparatus 400 grasps the size of the sheet S every time the sheet S is discharged from the apparatus main body 500A of the copying machine, and calculates an offset movement amount suitable for the sheet S. Based on the offset movement amount, the offset roller 407 is moved to align the side edge of the sheet with the width direction positioning wall 416.

  If the CPU 100 determines that the sheet is the final sheet (YES in S270), a sheet bundle corresponding to the copy document is formed on the processing tray 410. Next, is the stapling process selected? If it is selected (YES in S280), the stapler unit 420 is driven and the stapling process shown in FIG. 22 is executed (S290).

  When the stapling process is not selected (NO in S280) or when the stapling process is completed, as shown in FIG. 9, the CPU 100 moves the sheet bundle discharge member 413 that has gripped the sheet bundle SA by the sheet clamp member 412. The sheet bundle discharge motor 430 is advanced toward the stack trays 421 and 422 to discharge the sheet bundle SA (S300).

  Next, the CPU 100 performs the lowering process of the stack tray 421 in accordance with the discharge operation of the sheet bundle SA (S310), and then returns the sheet bundle discharge member 413 to the home position (S320). Thereafter, the CPU 100 stops the conveyance motor 431 in order to stop the rotation of the conveyance roller 405 and the offset roller 407 (S330), and turns off the pickup solenoid 433 (S340), thereby lowering the offset roller 407 and a series of operations. The process ends.

  The sheet processing apparatus 400 according to the present embodiment starts from the point at which the rotation amount of the offset roller 407 when the trailing edge of the sheet abuts against the trailing edge stopper 411 is switched back by stopping the conveyance of the sheet S. Since the rotation amount is such that it can be transported slightly more than the distance up to 411, in other words, even after the sheet S is transported by the distance at which the sheet S contacts the sheet trailing edge stopper 411 by the reverse rotation of the offset roller 407, the offset roller 407 Therefore, the sheet S can be reliably brought into contact with the sheet trailing edge stopper 411.

  The sheet processing apparatus 400 of this embodiment can align the trailing ends of the sheets S stably with a simple configuration that does not require many members. Further, since the sheet is not discharged so as to be skipped, the sheet can be stably conveyed with little fluctuation.

  The offset roller 407 moves the sheet in the width direction and abuts against the positioning wall 416 in the staple processing mode. However, if the offset roller 407 is not in the staple processing mode (the sheet is not bound), the sheet is not sorted. Alternatively, it may be discharged as it is.

  The stapler unit 420 is a fixed type and is disposed in the vicinity of the width direction positioning wall 416. However, the stapler unit 420 is not limited to this, and is movable so that it can move in the sheet conveying direction or the width direction. Also good. When the stapler unit 420 is made movable in this way, the stapler unit 420 can perform a stapling process for binding different portions or a plurality of locations in the sheet conveyance direction or width direction of the sheet bundle SA.

  Further, in the sheet processing apparatus of the present embodiment, the offset roller 407 is used to align the trailing edge and the side edge of the sheet. However, not the roller member but the member itself moves in the sheet conveyance direction to move the sheet. The same effect can be obtained by using the sheet conveying direction moving means for conveying and the sheet orthogonal direction moving means for moving the sheet in the width direction by moving in the direction orthogonal to the sheet conveying direction (width direction).

  Furthermore, the sheet processing apparatus according to the present embodiment stores a program corresponding to the control procedure shown in the flowcharts of FIGS. 20, 21, and 23 in the ROM 110, and the CPU 100 performs control while reading the program. The same effect can be obtained even if hardware is used for processing on the program.

  In the above description, the case where the CPU 100 of the sheet processing apparatus 400 performs the raising / lowering control of the stack trays 421 and 422 and the stapling operation control has been described. However, the present invention is not limited to this and is not limited to this. You may make it carry out by the control part 140 provided in the apparatus main body.

1 is a schematic front sectional view of an image forming apparatus according to an embodiment of the present invention. It is a schematic front sectional view of the sheet processing apparatus shown in FIG. It is a figure which shows a mode that a sheet | seat is discharged on the processing tray of the sheet processing apparatus shown in FIG. FIG. 2 is a perspective view of a drive mechanism for an offset roller and a conveyance roller of the sheet processing apparatus shown in FIG. 1. It is a figure for demonstrating operation | movement of the offset roller shown in FIG. 2, and the motion of a sheet | seat accompanying it. (A) is a figure of the state which has conveyed the sheet | seat discharged | emitted by the processing sheet once to the downstream side. (B) is a diagram showing a state where the sheet is conveyed back to the upstream side following (a). (C) is a figure of the state which has moved the sheet | seat to the width direction following (b). FIG. 6 is a diagram for explaining the operation following FIG. 5. (A) is a figure of the state which separated the offset roller from the sheet | seat following FIG.5 (c). (B) is the figure which returned the offset roller to the initial position following (a). It is a figure when a sheet clamp member has not pinched the sheet. (A) is a figure of the state which the sheet | seat contact | abutted to the rear-end stopper. (B) is a figure of the state which the sheet | seat contact | abutted to the width direction alignment positioning wall. FIG. 3 is a diagram for explaining a drive mechanism for a sheet bundle discharge member of the sheet processing apparatus shown in FIG. 2. (A) is a figure which has a sheet clamp member in a stand-by position. FIG. 6B is a diagram in which the sheet clamp member has moved to a position where the sheet bundle is discharged. FIG. 10 is a diagram for explaining an operation in which a sheet bundle discharge member discharges a sheet bundle to a stack tray. It is a figure for demonstrating the drive mechanism of the sheet clamp member of the sheet processing apparatus shown in FIG. It is a figure for demonstrating the drive mechanism of the pressing member of the sheet processing apparatus shown in FIG. (A) It is a figure when a pressing member exists in the position which presses a sheet | seat. (B) It is a figure when the pressing member exists in the position which is not pressing the sheet | seat. It is a figure of the raising / lowering apparatus which raises / lowers the stack tray of the sheet processing apparatus shown in FIG. FIG. 3 is a diagram for explaining movements of a stack tray (lower bin), a stack tray (upper bin), and a shutter of the sheet processing apparatus shown in FIG. 2. (A) The stack tray (lower bin) is in a position where sheets can be received, and the stack tray (upper bin) is retracted upward. (B) is a figure of the state which the stack tray (lower bin) fell from the state shown to (a). FIG. 3 is a diagram for explaining a shutter driving mechanism of the sheet processing apparatus shown in FIG. 2. (A) is a figure which shows the state which the shutter raised. (B) is a figure which shows the state which the shutter lowered | hung. FIG. 3 is a diagram for explaining movements of a stack tray (lower bin), a stack tray (upper bin), and a shutter of the sheet processing apparatus shown in FIG. 2. (A) is a figure showing the state where a shutter is closed. (B) is a diagram showing a state in which the stack tray (upper bin) is lowered with the shutter closed. FIG. 3 is a diagram for explaining movements of a stack tray (lower bin), a stack tray (upper bin), and a shutter of the sheet processing apparatus shown in FIG. 2. (A) is a figure which shows the state which the shutter opened from the state of FIG.15 (b). (B) is a figure which shows the state which closed the shutter following (a). FIG. 3 is a diagram for explaining movements of a stack tray (lower bin), a stack tray (upper bin), and a shutter of the sheet processing apparatus shown in FIG. 2. (A) is a figure which shows the state which closed the shutter and raised the stack tray (upper bin). FIG. 6B is a diagram illustrating a state where sheets can be stacked on the stack tray (lower bin). FIG. 3 is a diagram for explaining a configuration of a stack tray (lower bin) and a stack tray (upper bin) of the sheet processing apparatus shown in FIG. 2. (A) is a figure of the state in which the subtray is accommodated in the stack tray. (B) is a figure which shows the state by which the subtray was pulled out from the stack tray. FIG. 3 is a block diagram illustrating a configuration of a control unit of the sheet processing apparatus illustrated in FIG. 2. FIG. 3 is a flowchart for explaining a part of the sheet processing operation of the sheet processing apparatus shown in FIG. 2. FIG. 23 is a flowchart following FIG. 22. FIG. 3 is a diagram illustrating a state where a sheet offset by an offset roller illustrated in FIG. 2 is stapled. 6 is a flowchart for explaining an operation for providing a gap between a sheet stacked on a stack tray of an upper bin and a bottom surface of a reader unit. FIG. 10 is a diagram for explaining the operation of the stack tray for providing a gap between the sheets stacked on the stack tray of the upper bin and the bottom surface of the reader unit. (A) is a figure of the state which formed the clearance gap (space | interval) D between the sheet | seat loaded on the stack tray of an upper bin, and the bottom face of a reader part. FIG. 6B is a diagram illustrating a state where sheets can be stacked on the stack tray of the upper bin.

Explanation of symbols

S sheet D gap (interval) (predetermined distance between the rising restriction wall and the sheet stacked on the uppermost sheet stacking means)
SA sheet bundle SP The space where the side is open to the outside (lateral recess)
SP1 Sheet stacking space SPU Space 100 above the sheet discharge port 100 CPU (control means)
111 Movement amount counter (lifting distance counting means)
120 Reader unit 120a Bottom surface of reader unit (rising restriction wall)
200 Printer 400 Sheet Processing Device 400A Sheet Discharge Port (Sheet Discharge Unit)
400B Sheet processing unit 407 Offset roller 410 Processing tray 411 Sheet rear end stopper 412 Sheet clamp member 413 Sheet bundle discharge member 416 Positioning wall 420 Stapler unit 421 Stack bin of lower bin (sheet stacking means, lower sheet stacking means)
422 Upper bin stack tray (sheet stacking means, uppermost sheet stacking means)
500 Image forming apparatus 500A Image forming apparatus main body 509 Lifting device (lifting means)
530 Stack tray elevating motor 533 Rotating shaft 547 Upper limit detection sensor (detection means)
561 Coil spring 562a Stack tray clock disk (lifting distance counting means)
564 Stack tray clock sensor (lifting distance counting means)

Claims (5)

Image forming means for forming an image on a sheet;
A laterally recessed portion provided with an image forming sheet discharge portion for discharging a sheet on which an image is formed by the image forming means and having a side portion opened;
A sheet processing device provided in the space of the laterally recessed portion for processing a sheet discharged from the image forming sheet discharge unit,
The sheet processing apparatus includes a processing sheet discharge unit that discharges processed sheets, and a plurality of sheets that can be moved up and down arranged in a vertical direction in which the sheets discharged from the processing sheet discharge unit are stacked below the upper surface of the laterally recessed portion. An image forming apparatus comprising: a sheet stacking unit; and a lifting unit that independently lifts and lowers the plurality of sheet stacking units.
Lifting distance counting means for counting the lifting distance of the sheet stacking means;
Sheet height detecting means for detecting the height of the sheets stacked on the sheet stacking means;
Control means for controlling the lifting means based on the count of the lifting distance counting means so that the sheets discharged from the processing sheet discharge section are stacked on the selected sheet stacking means among the plurality of sheet stacking means; With
The control means includes
When switching the sheet stacking means for stacking sheets from the uppermost sheet stacking means to the lower sheet stacking means,
A first distance obtained by adding a predetermined interval and the height of the sheets stacked on the uppermost sheet stacking unit detected by the sheet height detecting unit is from the processing sheet discharge unit to the upper surface of the laterally-facing recess. If the distance is less than the second distance, the ascending / descending distance counting means reaches a position where the predetermined distance is provided between the upper surface of the laterally recessed portion and the uppermost sheet stacked on the uppermost sheet stacking means. Based on the count, the uppermost sheet stacking means is raised and stopped to switch from the uppermost sheet stacking means to the lower sheet stacking means,
When the first distance is equal to or greater than the second distance, switching from the uppermost sheet stacking unit to the lower sheet stacking unit is stopped.
An image forming apparatus. The uppermost sheet stacking means includes an upper limit detecting means for detecting that the uppermost sheet stacking means has been raised to the upper surface of the laterally-facing recess ,
The control means is obtained by subtracting a distance corresponding to the predetermined interval from the distance that the uppermost sheet stacking means descends from the upper surface of the laterally recessed portion to the stacking end position when the stacking of the sheets is completed. Elevating the uppermost sheet stacking means from the stacking end position by a distance ;
The image forming apparatus according to claim 1 . When the control unit causes the sheet stacking unit adjacent to the lowermost sheet stacking unit to stack the sheet, the uppermost sheet stacking unit completes stacking of the sheet on the lowermost sheet stacking unit. 3. The image forming apparatus according to claim 1, wherein the image forming apparatus is once raised upward at a position shorter than a distance corresponding to the predetermined interval and above the processing sheet discharge unit. The travel distance count unit, comprising an encoder rotated by the elevating means, and a detection sensor for detecting the number of clocks of the encoder,
The image forming apparatus according to claim 1 . The image forming unit and the lateral recess are provided in an image forming apparatus main body,
The control means is provided in either the image forming apparatus main body or the sheet processing apparatus.
The image forming apparatus according to claim 1, wherein the image forming apparatus is an image forming apparatus.

Images