JP2004262595A - Sheet processing device and image forming device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sheet processing device that can assure good loading and improve productivity without changing the configuration greatly. <P>SOLUTION: When the rear end of a sheet bundle S reaches a holding portion between a swing roller 550 and a rear end aligning wall 570, the roller 550 and the wall 570 control the timing of moving to the withdrawal position respectively to drop the sheet bundle S on a stack tray 504 and then align the rear end of the bundle S on the stack tray 504 by moving the wall 570 to the support position from the withdrawal position. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a sheet processing apparatus that performs processing such as stacking and aligning sheets, and transfers and stacks a processed bundle to a stacker unit.
[0002]
[Prior art]
A conventional sheet processing apparatus will be described with reference to FIG. FIG. 11 is a cross-sectional view illustrating the overall configuration of an image forming apparatus including a conventional sheet processing apparatus.
[0003]
As shown in FIG. 11, conventionally, in an image forming apparatus such as a printing machine, a copying machine, a printer, etc., a sheet S on which an image is formed by the image forming apparatus main body 200 is temporarily stacked on a processing tray 540 in the sheet processing apparatus 500. Then, sheet post-processing such as sheet S alignment and binding processing is performed.
[0004]
Thereafter, the bundle is discharged to the stack tray 581 having the inclined stacking surface as shown in FIG. 11 by the bundle discharging means 580, and the discharged sheet S moves on the inclined stacking surface of the stack tray 581 by its own weight, and the rear end is aligned. The trailing edge of the sheet is aligned at the wall. The number of stacked sheets depends on the vertical operation stroke of the stack tray 581.
[0005]
[Problems to be solved by the invention]
However, the stack of sheets is slipped down onto a stack tray 504 that is configured substantially horizontally as shown in FIG. 6, and the rear end of the stack of sheets S is pushed out and stacked by the rear alignment wall to secure the stacking amount. In such a configuration, if the timing for releasing the holding of the swing roller 550 and the driven roller 571 for holding the sheet bundle up and down does not match, the sheet bundle will be separated, and the stackability on the stack tray 504 will be impaired.
[0006]
In addition, if the sheet height cannot be accurately determined, an attempt is made to stack sheets in excess of the allowable number of sheets, so that further deterioration of stacking properties such as dropping of sheets from the stack tray 504 occurs.
[0007]
SUMMARY OF THE INVENTION The present invention has been made in view of the above-described problems of the related art, and an object of the present invention is to provide a sheet processing apparatus that achieves good loadability and improves productivity without significantly changing the configuration. To provide.
[0008]
[Means for Solving the Problems]
In order to achieve the above object, in the sheet processing apparatus according to the present invention,
Intermediate processing means for stacking and processing the sheets conveyed from the sheet conveying means,
Loading means for loading the sheet bundle processed by the intermediate processing means,
A first support unit selectively movable to a support position for supporting the upper surface of the sheet bundle processed by the intermediate processing unit or to a retracted position retracted from the upper surface of the sheet bundle;
A second support unit that is selectively movable to a support position for supporting the lower surface of the sheet bundle processed by the intermediate processing unit or to a retracted position retracted from the lower surface of the sheet bundle;
Switching control means for independently switching the support position and the retreat position with respect to the first support means and the second support means,
A transfer unit capable of transferring the sheet bundle supported by the first support unit and the second support unit to the stacking unit,
The switching control means,
When the rear end of the sheet bundle reaches the holding portion between the first support means and the second support means by the transfer means, the first support means and the second support means move to the retracted position. The sheet bundle is dropped on the stacking means by controlling the timing of
Thereafter, the rear end of the sheet bundle dropped on the stacking unit is aligned by moving the second support unit from the retracted position to the support position.
[0009]
According to the above configuration, the sheet bundle is sandwiched between the first support member and the second support member from above and below, and the timing of moving the sheet bundle to the retracted position in order to release the sandwiched state is controlled. The sheet bundle can be prevented from being separated when the sheet bundle falls, and the stacking quality of the sheet bundle on the stacking means is improved. In addition, since the sheet height can be accurately determined, it is possible to prevent the sheets from being stacked in excess of the allowable number and to prevent the sheets from dropping from the stacking unit.
[0010]
It is preferable that the switching control unit controls the timing at which the first support unit moves to the retreat position at the same time as or earlier than the timing at which the second support unit moves to the retreat position.
[0011]
According to this configuration, the force applied to the sheet bundle is released by retreating the first support means that supports the upper surface of the sheet bundle even when the holding state is released while the sheet bundle is curved. Therefore, it is possible to prevent the sheet bundle from being separated when the sheet bundle is dropped on the stacking unit, and the stacking quality of the sheet bundle on the stacking unit is improved.
[0012]
It is preferable that the elastic force of the second support member in a supported state is smaller than the elastic force of the first support member in a supported state.
[0013]
In the image forming apparatus according to the present invention,
The sheet processing apparatus;
Image forming means for forming an image on a sheet conveyed to the sheet processing apparatus;
It is characterized by having.
[0014]
BEST MODE FOR CARRYING OUT THE INVENTION
Preferred embodiments of the present invention will be illustratively described in detail below with reference to the drawings. However, the dimensions, materials, shapes, relative arrangements, and the like of the components described in this embodiment are not intended to limit the scope of the present invention thereto unless otherwise specified. Absent.
[0015]
Hereinafter, embodiments of a sheet processing apparatus according to the present invention and an image forming apparatus including the sheet processing apparatus will be specifically described with reference to the drawings.
[0016]
(overall structure)
FIG. 1 is a cross-sectional view showing the overall configuration of an image forming apparatus main body equipped with a sheet processing apparatus according to the present embodiment, FIG. 2 is a top view of the sheet processing apparatus according to the present embodiment, and FIG. FIG. 2 is a cross-sectional view illustrating a schematic configuration of a sheet processing apparatus according to the embodiment.
[0017]
However, according to the present invention, the sheet stacking aligning device that aligns and stacks the image-formed sheets S discharged from the image forming apparatus main body 200 on the stack tray 504 does not pass through the processing tray 540 but directly to the image forming apparatus main body 200. The present invention is also effective for a connected device or a device in which the sheet processing apparatus 500 is mounted outside the image forming apparatus main body 200.
[0018]
In FIG. 1, a sheet processing apparatus 500 is mounted on an image forming apparatus main body 200. An automatic document reading device 100 is mounted on an upper portion of the image forming apparatus main body 200. Although the image forming apparatus is configured by the image forming apparatus main body 200, the sheet processing apparatus 500, and the automatic document reading apparatus 100, the sheet processing apparatus 500 may not include the processing tray 540.
[0019]
As shown in FIG. 1, a document reading unit 150 is mounted on the image forming apparatus main body 200, and the document reading device 100 is mounted on the document reading unit 150. The document reading device 100 separates the document set upward from above, feeds the documents one by one in order from the first page to the left, transports the document onto the platen glass 102 via a curved path, and reads the document. Thereafter, the sheet is discharged to the sheet discharge tray 112.
[0020]
In the automatic document reading apparatus 100, the light of the lamp of the scanner unit 104 is irradiated on the document, and the reflected light from the document is guided to the image sensor 109 via the mirrors 105, 106 and the lens 107 to read the document. Is performed. The image of the document read by the image sensor 109 is subjected to image processing, sent to the exposure control unit 202 of the image forming apparatus main body 200, and emitted a laser beam.
[0021]
Next, in the exposure control unit 202, the laser light is reflected by the rotating polygon mirror, and is again turned back by the reflection mirror, so that the surface is uniformly charged on the photosensitive drum 203 serving as image forming means. Irradiation forms an electrostatic latent image. After the electrostatic latent image on the photosensitive drum 203 is developed by the developing device 205, it is transferred as a toner image onto a sheet S composed of paper, an OHP sheet, or the like.
[0022]
The sheet S is appropriately and selectively fed out of the sheet cassettes 231, 232, 233, and 234 by a pickup roller 238 constituting a sheet feeding unit, separated by a separating unit 237, and fed one by one. After the skew is corrected, the toner image is sent to the transfer position in synchronization with the rotation of the photosensitive drum 203, and the toner image formed on the photosensitive drum 203 is transferred to the sheet S via the transfer belt 211.
[0023]
Thereafter, the sheet S is guided to the fixing roller pair 206, and the toner image transferred to the sheet S after being heated and pressed by the fixing roller pair 206 is permanently fixed. The upper fixing claw and the lower fixing claw are in contact with the fixing roller pair 206, respectively, whereby the sheet S is separated from the fixing roller pair 206.
[0024]
The separated sheet S is conveyed to the outside of the image forming apparatus main body 200 by the main body side discharge roller pair 207, and is guided to the sheet processing apparatus 500 connected to the image forming apparatus main body 200.
[0025]
(Sheet processing device configuration)
Next, the configuration of the sheet post-processing apparatus 500 will be specifically described.
[0026]
In FIG. 1, the sheet processing apparatus 500 includes a processing tray 540, which is a sheet stacking unit disposed on the upstream side, and a stack tray 504 disposed substantially horizontally on the downstream side. The sheet S discharged from the main body side discharge roller pair 207 of the image forming apparatus main body 200 is post-processed by the processing tray 540 and is stacked on the stack tray 504.
[0027]
The post-processing mode performed on the processing tray 540 includes a sort mode for sorting a plurality of sets, a staple mode (staple) mode for binding a plurality of sheets by the staple unit 510, and the like. Selected and set by means.
[0028]
In the staple binding mode, a staple binding position such as one-point binding or two-point binding can be selected, and the staple unit 510 moves to the actual staple binding position based on the settings such as the sheet size and the binding position.
[0029]
As shown in FIG. 2 and FIG. 3, the sheet S discharged from the image forming apparatus main body 200 is directed toward the stack tray 504 by a discharge unit including a discharge roller 508a on the sheet processing apparatus 500 side and a discharge roller 508b driven by the discharge roller 508a. At the timing when the trailing end of the sheet S has passed the discharge section, the trailing end of the sheet S is dropped onto the processing tray 540 by the swing roller 550 and is nipped by the swing roller 550 and the driven roller 571. .
[0030]
<Swing roller configuration>
The operation of the swing arm 551 and the swing roller 550 will be described with reference to FIGS. FIG. 4 is a cross-sectional view illustrating the operation of the swing roller of the sheet processing apparatus according to the present embodiment, and FIG. 8 is a block diagram illustrating a control unit of the sheet processing apparatus according to the present embodiment.
[0031]
As shown in FIG. 4, the swing roller 550 is attached to a swing arm 551 that can swing vertically about a swing roller shaft 552.
[0032]
The drive from the swing arm drive motor 643 is transmitted to the swing arm shaft 553 of the swing arm 551 via the swing cam 554. When the swing arm drive motor 643 rotates, the swing arm 551 is moved. It swings up and down about the swing roller shaft 552 integrally with the swing cam 554.
[0033]
A swing arm extension spring 555 is mounted on the swing arm 551 to assist upward swing.
[0034]
The oscillating roller 550 is connected to an oscillating roller driving motor 642 from an oscillating roller shaft 552 via an oscillating roller driving belt 556 and an oscillating roller driven pulley 557, and a driving signal is transmitted from a CPU 611 shown in FIG. When transmitted to the swinging roller drive motor 642 via the moving roller drive motor driver 622, the swinging roller 550 rotates.
[0035]
(Swing roller operation)
Next, the operation of the swing roller 550 will be described in detail with reference to FIG.
[0036]
The home position of the oscillating roller 550 is set at an upper portion that does not come into contact with the sheet S discharged onto the processing tray 540 by the discharge unit (FIG. 4A).
[0037]
When the sheet S is discharged from the discharge section, the swing arm 551 is driven by the swing arm drive motor 643 and rotates counterclockwise around the swing roller shaft 552, whereby the swing roller 550 is lowered. Then, the trailing end of the sheet S is pressed by the swing roller 550, and the trailing end of the sheet is dropped into the processing tray 540 (FIG. 4B).
[0038]
The oscillating roller 550 forms a nip with the driven roller 571, and rotates counterclockwise under the drive of the oscillating roller drive motor 642, so that the rear end of the sheet S on the processing tray 540 returns to the return belt 560. The sheet S is pulled in along the lower guide 561 in the direction opposite to the previous conveying direction until the sheet S comes into contact with the sheet S (FIG. 4C).
[0039]
Thereafter, the swing roller 550 moves up to the home position again, and prepares for discharging the next sheet S (FIG. 4A).
[0040]
(Return belt operation)
Next, the operation of the return belt will be described with reference to FIGS. FIG. 5 is a cross-sectional view illustrating the operation of the return belt of the sheet processing apparatus according to the present embodiment.
[0041]
The return belt 560 is supported vertically by the discharge roller shaft 509 and is normally set at a position where it comes into contact with the sheet S on the processing tray 540.
[0042]
A return belt 560, which is at least one or more sheet feed rotating members, is disposed in a direction perpendicular to the direction in which the sheet S abuts against the sheet rear end stopper 562. The return belt 560 is supported by the discharge roller 508a and the housing 563. The configuration is such that a belt 565 is interposed on a belt pulley 564 (see FIG. 3). The return belt 560 conveys the sheet S in the direction of the sheet rear end stopper 562 as the discharge roller shaft 509 rotates counterclockwise (FIG. 5A).
[0043]
Further, the return belt 560 is adapted to escape in the thickness direction of the sheets according to the number of sheets S stacked on the processing tray 540 (FIG. 5B).
[0044]
As described above, the counter-clockwise rotation of the swing roller 550 and the return belt 560 causes the rear end of the sheet S to be positioned at the end of the processing tray 540, and to be a sheet receiving unit that receives the sheet S on the processing tray 540. The sheet S is sent to the rear end stopper 562, and the sheet S is aligned one by one in the sheet conveying direction.
[0045]
(Sheet width direction alignment)
The alignment in the sheet width direction will be described with reference to FIGS.
[0046]
The front alignment plate 541 and the rear alignment plate 542 are driven by a front alignment motor 646 and a rear alignment motor 647, respectively, and move in a direction parallel to the discharge roller shaft 509.
[0047]
When the sheet processing apparatus 500 is not operating, the front alignment plate 541 and the rear alignment plate 542 stand by at positions where the front alignment home position sensor 530 and the rear alignment home position sensor 531 (not shown) are detected. This position is called an alignment home position position, and is set at a position where the sheet does not hit the front alignment plate 541 and the rear alignment plate 542 when the sheet is conveyed.
[0048]
The front alignment plate 541 and the rear alignment plate 542 move to a standby position according to the size of the sheet S before the sheet S is conveyed from the image forming apparatus main body 200. After the sheet S is aligned in the transport direction as described above, the front alignment plate 541 and the rear alignment plate 542 move to the alignment position in the post-processing mode set before the start of the job, thereby aligning the sheet S in the sheet width direction. Is performed.
[0049]
For example, when the sort mode is selected, when aligning the Nth sheet in the width direction, the front alignment plate 541 waits at the reference position, and the rear alignment plate 542 moves from the standby position to the sheet alignment position. Thus, the alignment is performed based on the front side, and the sheet is discharged to the stack tray 504 by the operation described later.
[0050]
When aligning the (N + 1) th sheet, the rear aligning plate 542 waits at the reference position, and the front aligning plate 541 moves from the standby position to the sheet aligning position to perform alignment based on the rear side, and stacks. The sheet is discharged to the tray 504.
[0051]
Thus, the sheets can be stacked on the stack tray 504 in a state of being sorted each time the bundle is discharged.
[0052]
Of course, it is also possible to perform alignment based on the center position of the sheet. In this case, the alignment is performed by moving both the front alignment plate 541 and the rear alignment plate 542 from the standby position to the alignment position based on the center position.
[0053]
When the staple binding mode is selected, the above-described width alignment operation is performed at a position corresponding to the set staple binding position.
[0054]
When the staple binding mode is selected, the staple binding operation is subsequently performed. The staple unit 510 performs a staple binding operation by driving a staple clinch motor 648. The staple unit 510 can be moved in the front-rear direction by driving a staple slide motor 649.
[0055]
When a job is started, the staple unit 510 moves to the actual staple binding position determined from the contents of the staple binding position set before the start of the job and the sheet size. The staple unit 510 performs a staple binding operation on the aligned sheet bundle S that has been subjected to the width direction alignment described above.
[0056]
(Bunch discharging means)
Next, the bundle discharging means will be described with reference to FIGS. FIG. 6 is a cross-sectional view illustrating a sheet bundle discharging operation of the sheet processing apparatus according to the present embodiment.
[0057]
After the alignment in the sheet conveying direction, the alignment in the sheet width direction, and the staple binding operation, the swing roller 550 is driven by the swing arm drive motor 643 and abuts on the sheet bundle S about the swing roller shaft 552. (FIG. 6A), forming a nip with the driven roller 571 disposed at the upper end of the rear end alignment wall 570, and then rotating clockwise, the rear end of the sheet bundle S becomes the upper end of the rear end alignment wall 570. The sheet is transported until it reaches the vicinity, and stopped (FIG. 6B).
[0058]
Thereafter, the swing roller 550 separates from the sheet bundle S and returns to the home position (FIG. 6C). At substantially the same time, the rear end alignment wall 570 swings about the cam swing rotation shaft 573 at a moving speed V1 in the direction opposite to the sheet conveyance by the cam 572 located below the rear end alignment wall 570.
[0059]
If there is enough processing time, as shown in FIG. 11, the movement start timing of the trailing end alignment wall 570 is canceled by the swing roller 550 being separated from the sheet bundle S and the nip pressure (clamping pressure) is released (clamping pressure). It may be performed after the pressure is reduced to 0). When the sandwiched state is released in a state where the sheet bundle is curved, the swinging roller 550 supporting the upper surface of the sheet bundle is retracted at the same time or earlier, so that the force applied to the sheet bundle is released. It is possible to prevent the sheet bundle from being separated when the sheet bundle is dropped, and the stacking quality of the sheet bundle on the stacking unit is improved.
[0060]
Further, it is desirable that the elastic force of the driven roller 571 in a state where the sheet bundle S is sandwiched between the oscillating roller 550 and the driven roller 571 is set smaller than the elastic force of the oscillating roller 550. As a result, the weight of the sheet bundle is securely supported by the lower surface of the sheet bundle, abrupt load change does not occur when the nip pressure is released, and the sheet bundle can be maintained in a good alignment state. The loading quality of the bundle is improved.
[0061]
(Sheet trailing edge alignment)
Means for discharging the sheet bundle S on the processing tray 540 onto the stack tray 504, aligning and stacking the sheets will be described with reference to FIGS. FIG. 7 is a cross-sectional view illustrating the aligning operation of the trailing end of the sheet bundle of the sheet processing apparatus according to the present embodiment. FIG. 10 is a diagram illustrating the moving speed (driving) of the trailing end aligning wall motor according to the present embodiment. 6 is a graph showing a relationship between (velocity) and a change in position.
[0062]
The rear end alignment wall 570 is urged by a spring 512, and swings about a swing rotation shaft 573 by contacting the cam 572 at the home position (FIGS. 3 and 7).
[0063]
In a state in which the rear end of the sheet bundle S discharged by the bundle discharging unit is in contact with the upper end of the rear end alignment wall 570 (FIG. 6B), the rear end alignment wall 570 is moved upstream in the sheet conveyance direction at the moving speed V1. The sheet bundle S is retracted (FIG. 6C), and the rear end of the sheet bundle S is brought into contact with the slope of the rear end alignment wall 570 (FIG. 7A). In order to enhance the accuracy of the sheet rear end alignment, the home position of the rear end alignment wall 570 is detected by the rear end alignment wall home position sensor 523 (FIG. 8).
[0064]
In the process of returning the retracted rear end alignment wall 570 to the home position at the moving speed V2 about the center of the rotation axis, the rear end of the sheet bundle S is pressed in the horizontal direction by the rear end alignment wall 570, so that the sheet bundle S is pressed. The sheet bundle S is stacked on the stack tray 504 while aligning the rear end (FIGS. 7B and 7C).
[0065]
As shown in FIG. 10, the drive control of the rear end matching wall motor according to the present embodiment is as follows. First, when the evacuation is performed, the motor is driven to the moving speed V1. The rear end alignment motor is stopped. After a predetermined time elapses after the stop, the return operation is started, and the rear end alignment motor is driven to the moving speed V2. When the movement is completed, the rear end alignment motor is stopped.
[0066]
Further, by setting the above-mentioned moving speed V1 and moving speed V2 in a relationship of V1> V2, the processing time required for discharging the sheet bundle can be reduced while maintaining the alignment quality by the rear end alignment wall 570. I have.
[0067]
The sheet bundle placed on the stack tray 504 is pulled back by the sheet return member 583 to the rear end alignment wall 570 side after the sheet bundle is discharged, and is pressed down from the upper surface of the sheet bundle.
[0068]
More specifically, the sheet processing apparatus according to the present invention includes an intermediate processing unit (for example, an intermediate processing unit (for example, a stacking unit) that stacks and processes the sheet S conveyed from the sheet conveying unit (for example, the main body side discharge roller pair 207). A staple unit 510), a stacking unit (for example, a stack tray 504) for stacking the sheet bundle processed by the intermediate processing unit, and a support position or a sheet supporting the upper surface of the sheet bundle processed by the intermediate processing unit. A first support unit (for example, a swing roller 550) that can be selectively moved to a retreat position retracted from the upper surface of the bundle, and a support position that supports the lower surface of the sheet bundle processed by the intermediate processing unit or the sheet. Second support means (for example, a rear end alignment wall 570) which can be selectively moved to a retracted position retracted from the lower surface of the bundle, the first support means and the Switching control means for independently switching between the support position and the retreat position with respect to the second support means, and the stack of sheets supported by the first support means and the second support means. A transfer unit capable of transferring the sheet, wherein the switching control unit is configured such that a rear end of a sheet bundle is held between the first support unit and the second support unit by the transfer unit. The sheet bundle is dropped on the stacking means by controlling the timing at which the first support means and the second support means move to the retreat position, and thereafter, the second support means The rear end of the sheet bundle dropped onto the stacking unit is aligned by moving the unit from the retracted position to the supporting position.
[0069]
Here, as the switching control unit, a unit that detects the movement of the sheet bundle by an electric sensor and controls the movement between the support position of the rear end alignment wall as the support unit and the retreat position, Further, the movement of the sheet bundle may be mechanically transmitted to the movement of the rear end alignment wall. The switching control unit may be provided in the sheet post-processing apparatus, or may be provided in a control unit of the image forming apparatus.
[0070]
(Seat return member)
A sheet return member (hereinafter, referred to as a “paddle”) 583 which is a paddle-shaped member rotates around a paddle rotation shaft 590 (see FIGS. 6 and 7) extending inside the rear end alignment wall 570. I have. The paddle 583 rotates the counter-clockwise rotation of the paddle 583 one time each time the sheet bundle is discharged onto the stack tray 504 by the swing roller 550, so that the discharged sheet bundle moves toward the rear end alignment wall 570. Each time it is pulled back, the rear end of the sheet bundle can be held down.
[0071]
The paddle 583 is held in a state as shown in FIGS. 6A and 6B except during the sheet returning operation, and holds the sheet S. At this time, the position of the paddle 583 is detected by a paddle home position sensor 532 (not shown).
[0072]
The stack tray 504 is configured to be able to move up and down by a driving unit (not shown) in order to keep the upper surface height of the stacked sheet bundle S constant.
[0073]
In the present embodiment, the sheet stacking surface of the stack tray 504 is set to be substantially horizontal. However, even when the sheet stacking surface is inclined, the sheet trailing edge alignment means works effectively, and the sheet stacking surface is The effect is further enhanced in the case of being substantially horizontal. Further, the sheet stacking surface 504a is inclined downward by 18 ° or less toward the sheet rear end alignment wall, so that the sheet bundle already stacked on the stack tray 504 is discharged from the processing tray 540. The apparatus can be downsized while avoiding interference with a subsequent sheet bundle.
[0074]
(System block configuration)
Next, the configuration of a controller that controls the entire image forming apparatus will be described with reference to FIG. FIG. 9 is a block diagram illustrating a configuration of a controller that controls the image forming apparatus according to the present embodiment.
[0075]
As shown in FIG. 9, the controller has a CPU circuit section 350, and the CPU circuit section 350 includes a CPU 351, a ROM 352, and a RAM 353. The CPU circuit section 350 has an external I / F 320, an image signal control section 330, a printer control section 340, a RAM 353, a document feeder control section 360, an image reader control section 370, and sheet processing according to control programs stored in the ROM 352. Each block of the device control unit 600 is generally controlled.
[0076]
The RAM 353 temporarily stores control data and is used as a work area for arithmetic processing associated with control.
[0077]
The document feeder control section 360 controls the drive of the document reading apparatus 100 based on an instruction from the CPU circuit section 350.
[0078]
The image reader control unit 370 performs drive control on the above-described scanner unit 104, image sensor 109, and the like, and transfers an analog image signal output from the image sensor 109 to the image signal control unit 330.
[0079]
After converting the analog image signal from the image sensor 109 into a digital signal, the image signal control unit 330 performs various processes, converts the digital signal into a video signal, and outputs the video signal to the printer control unit 340. Further, the digital image signal input from the computer 310 via the external I / F 320 is subjected to various processes, and the digital image signal is converted into a video signal and output to the printer control unit 340. The processing operation of the image signal control unit 330 is controlled by the CPU circuit unit 350.
[0080]
The printer control unit 340 drives the above-described laser scanner unit 202 based on the input video signal.
[0081]
The operation unit 363 includes a plurality of keys for setting various functions related to image formation, a display unit for displaying information indicating a setting state, and the like, and outputs a key signal corresponding to an operation of each key to the CPU circuit unit 350. At the same time, the corresponding information is displayed on the display unit based on the signal from the CPU circuit unit 350.
[0082]
The sheet processing apparatus control unit 600 is mounted on the sheet processing apparatus 500, and controls driving of the entire sheet processing apparatus by exchanging information with the CPU circuit unit 350. The details of this control will be described later.
[0083]
(Sheet processing device block diagram)
Next, a configuration of the sheet processing apparatus control unit 600 that controls the driving of the sheet processing apparatus 500 will be described with reference to FIG. FIG. 8 is a block diagram illustrating a configuration of the sheet processing apparatus control unit according to the present embodiment.
[0084]
As shown in FIG. 8, the sheet processing device control unit 600 includes a CPU circuit unit 610 including a CPU 611, a ROM 612, a RAM 613, and the like. The CPU circuit section 610 communicates with the CPU circuit section 350 provided on the image forming apparatus main body 200 side via the communication IC 614 to exchange data, and various types of data stored in the ROM 612 based on instructions from the CPU circuit section 350. The drive of the sheet processing apparatus 500 is controlled by executing the program.
[0085]
When performing this drive control, detection signals from various sensors are taken into the CPU circuit section 610.
[0086]
Various sensors include an entrance sensor 521, a swing home position sensor 522, a rear end matching wall home position sensor 523, a tray detection sensor 524, a paper surface detection sensor 525, a return belt retreat sensor 526, a staple slide home position sensor 527, and a staple clinch. There is a home position sensor 528.
[0087]
Drivers 621 to 630 of each motor are connected to the CPU circuit unit 610, and each driver drives the motor based on a signal from the CPU circuit unit 610.
[0088]
Here, as the motor, a pair of entrance conveyance rollers 520, a discharge motor 641 that is a driving source of the return belt 560, and a swing roller 550 attached to the tip of the swing arm 551 for the sheet conveyed by the entrance conveyance roller pair 520. The swing roller drive motor 642 serves both as a drive for returning the sheet and a drive for discharging the bundle of sheets processed on the processing tray 540 to the stack tray 504. The swing roller driving motor 642 swings to catch the rear end of the sheet discharged to the processing tray 540. A swing arm drive motor 643, which is a drive source for driving the moving arm 551 in the vertical direction, and a drive source for driving the rear end alignment wall 570 for aligning the rear end of the sheet bundle discharged onto the stack tray 504. A paddle which is a pressing member for pressing down the rear end of a bundle of sheets stacked on the stack tray 504 with a certain rear end aligning wall drive motor 644 A front alignment motor 646, a rear alignment motor 647, and a staple unit 510 are driving sources of a paddle motor 645, an alignment plate that aligns the sheets stacked on the processing tray 540 in a direction perpendicular to the sheet conveyance direction, and a staple unit 510. Include a staple slide motor 649 as a drive source for driving the stack tray 504, a stack tray motor 650 as a drive source for the stack tray 504, and a staple clinch motor 648 as a drive source for stapling the staple unit 510.
[0089]
The discharge motor 641, the swing roller drive motor 642, the swing arm drive motor 643, the rear end alignment wall drive motor 644, the paddle motor 645, the front alignment motor 646, the rear alignment motor 647, and the staple slide motor 649 are composed of stepping motors. By controlling the excitation pulse rate, the roller pair driven by each motor can be rotated at a constant speed or at a unique speed.
[0090]
Also, a paper discharge motor 641, a swing roller drive motor 642, a swing arm drive motor 643, a front alignment motor 646, a rear alignment motor 647, and a staple slide motor 649 are a paper discharge motor driver 621, a swing roller drive motor driver 622, respectively. The motor can be driven in forward and reverse directions by a swing arm drive motor driver 623, a front alignment motor driver 626, a rear alignment motor driver 627, and a staple slide motor driver 629.
[0091]
The staple clinch motor 648 and the stack tray motor 650 are DC motors.
[0092]
【The invention's effect】
As described above, according to the present invention, it is possible to prevent the sheet bundle from being separated when it falls on the stacking means, and the stacking quality of the sheet bundle on the stacking means is improved. In addition, since the sheet height can be accurately determined, it is possible to prevent the sheets from being stacked in excess of the allowable number and to prevent the sheets from dropping from the stacking unit.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view illustrating an overall configuration of an image forming apparatus including a sheet processing apparatus according to an embodiment.
FIG. 2 is a top view of the sheet processing apparatus according to the embodiment.
FIG. 3 is a cross-sectional view illustrating a schematic configuration of a sheet processing apparatus according to the embodiment.
FIG. 4 is a cross-sectional view illustrating an operation of a swing roller of the sheet processing apparatus according to the embodiment.
FIG. 5 is a cross-sectional view illustrating an operation of a return belt of the sheet processing apparatus according to the embodiment.
FIG. 6 is a cross-sectional view illustrating a sheet bundle discharging operation of the sheet processing apparatus according to the embodiment.
FIG. 7 is a cross-sectional view illustrating an operation of aligning the rear end of the sheet bundle of the sheet processing apparatus according to the embodiment.
FIG. 8 is a block diagram illustrating a control unit of the sheet processing apparatus according to the embodiment.
FIG. 9 is a block diagram illustrating a configuration of a controller that controls the image forming apparatus according to the embodiment.
FIG. 10 is a time chart showing a driving state of a rear end matching wall motor.
FIG. 11 is a cross-sectional view illustrating an overall configuration of an image forming apparatus including a conventional sheet processing apparatus.
FIG. 12 is a time chart showing a transition of a holding pressure after a bundle is discharged.
[Explanation of symbols]
S sheet (sheet bundle)
REFERENCE SIGNS LIST 100 Document reading device 150 Document reading unit 200 Image forming device main body 202 Exposure control unit 203 Photoconductor drum 205 Developing device 206 Fixing roller pair 211 Transfer belt 500 Sheet processing device 504 Stack tray 508a Discharge roller 508b Discharge roller 509 Discharge roller shaft 510 Staple Unit 512 Rear end alignment wall disturbing spring 520 Inlet transport roller pair 521 Inlet sensor 522 Swing home position sensor 523 Swing home position sensor 524 Tray detection sensor 525 Paper surface detection sensor 526 Belt retreat sensor 527 Staple slide home position sensor 528 Staple Clinch home position sensor 530 Front alignment home position sensor 531 Rear alignment home position sensor 532 Paddle home position sensor 540 Processing tray 541 Front alignment plate 542 Rear alignment plate 550 Swing roller 551 Swing arm 552 Swing roller shaft 553 Swing arm shaft 554 Swing cam 555 Swing arm extension spring 556 Swing roller drive belt 557 Swing roller driven Pulley 560 Return belt 561 Lower guide 562 Sheet rear end stopper 563 Housing 564 Return belt pulley 565 Belt 570 Rear end alignment wall 571 Followed roller 572 Cam 573 Swing rotation shaft 574 Pinion gear 575 Rear end alignment wall Home position sensor 580 Bundle discharging means 581 Stack tray 582 Gripper 583 Sheet return member (paddle)
585 Tip regulation plate 590 Paddle rotating shaft 600 Sheet processing device control unit 610 Circuit unit 641 Discharge motor 642 Swing roller drive motor 643 Swing arm drive motor 644 Rear end alignment wall drive motor 645 Paddle motor 646 Front alignment motor 647 Rear alignment Motor 648 Staple clinch motor 649 Staple slide motor 650 Stack tray motor

Claims (4)

Intermediate processing means for stacking and processing the sheets conveyed from the sheet conveying means,
Loading means for loading the sheet bundle processed by the intermediate processing means,
A first support unit selectively movable to a support position for supporting the upper surface of the sheet bundle processed by the intermediate processing unit or to a retracted position retracted from the upper surface of the sheet bundle;
A second support unit that is selectively movable to a support position for supporting the lower surface of the sheet bundle processed by the intermediate processing unit or to a retracted position retracted from the lower surface of the sheet bundle;
Switching control means for independently switching the support position and the retreat position with respect to the first support means and the second support means,
A transfer unit capable of transferring the sheet bundle supported by the first support unit and the second support unit to the stacking unit,
The switching control means,
When the rear end of the sheet bundle reaches the holding portion between the first support means and the second support means by the transfer means, the first support means and the second support means move to the retracted position. The sheet bundle is dropped on the stacking means by controlling the timing of
Thereafter, the rear end of the sheet bundle dropped on the stacking unit is aligned by moving the second support unit from the retracted position to the support position. The switching control means controls the timing at which the first support means moves to the retreat position at the same time or earlier than the timing at which the second support means moves to the retreat position. 2. The sheet processing apparatus according to 1. The sheet processing apparatus according to claim 1, wherein an elastic force of the second support member in a supported state is smaller than an elastic force of the first support member in a supported state. A sheet processing apparatus according to any one of claims 1 to 3,
Image forming means for forming an image on a sheet conveyed to the sheet processing apparatus;
An image forming apparatus comprising:

Images