JP2000063033A - Paper after-treatment device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To dissolve tasks generating defective delivery such as buckling and the like of papers caused by a ratio in the number of sheets of large size papers to small size papers. SOLUTION: This device includes a stitching means 9 stitching the plural number of papers, a tray to which bundles of papers stitched by the stitching means are delivered, an emission means 26 emitting stitched bundles of papers by the stitching means, and a delivery means 12 delivering the bundles of papers emitted out of the emission means to the tray, and the linear velocity of the emission means is equated with that of the delivery means when the bundle of papers mixed with papers different in size is delivered to the tray.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a copying machine, a printer,
The present invention relates to a sheet post-processing apparatus having a function of binding a plurality of sheets discharged from an image forming apparatus such as a facsimile and discharging the sheets to a tray.

[0002]

2. Description of the Related Art A sheet post-processing apparatus includes a binding unit for binding a plurality of sheets ejected from an image forming apparatus into a sheet bundle, and a sheet ejection tray for ejecting the sheet bundle bound by the binding unit. There is one that has a discharge belt for pushing out and discharging the sheet bundle bound by the binding means with a discharge claw, and a discharge roller for discharging the sheet bundle discharged from the discharge belt to the discharge tray.

In such a sheet post-processing apparatus, the sheet bundle discharging linear velocity of the discharging belt is discharged in order to prevent the leading edge of the sheet from being bent or wrinkled when the bound sheet is discharged to the discharge tray. It is known from JP-A-4-176694 and JP-A-7-2281212 that the speed is set higher than the linear velocity of the sheet bundle discharge of the paper roller, and the stop position of the discharge claw of the discharge belt is appropriately determined accordingly. ing.

[0004]

The linear discharge speed of the sheet bundle of the discharge belt is made higher than the linear discharge speed of the sheet bundle of the discharge roller, and the stop position of the discharge claw of the discharge belt is appropriately determined accordingly. The sheet post-processing apparatus is suitable for ejecting a sheet bundle when the sheets of the sheet bundle have the same size, but is large when ejecting a sheet bundle in which sheets of different sizes are mixed to the tray. Depending on the ratio of the number of sheets of small size paper to that of small size paper, discharge defects such as buckling of paper may occur near the discharge rollers.

It is an object of the present invention to provide a sheet post-processing apparatus capable of surely discharging a sheet bundle when a sheet bundle in which sheets of different sizes are mixed is discharged to a tray. .

According to the second aspect of the invention, when the sheet bundle on which the sheets of different sizes are mixed is discharged to the tray, the sheet bundle can be reliably discharged, and the stackability of the sheets on the tray is improved. An object of the present invention is to provide a sheet post-processing device that can be used.

The invention according to claim 3 can improve the stackability of the sheets on the tray when discharging a sheet bundle in which sheets of different sizes are mixed to the tray, and tends to occur when the sheet size is large. An object of the present invention is to provide a sheet post-processing device capable of preventing a bundle of sheets from falling from a tray.

In the invention according to claim 4, when a sheet bundle in which sheets of different sizes are mixed is discharged to the tray, the sheet bundle can be reliably discharged, and the stackability of the sheets on the tray is improved. It is an object of the present invention to provide a sheet post-processing device that can prevent falling of a sheet bundle that tends to occur when the sheet size is large from the tray.

[0009]

In order to achieve the above object, the invention according to claim 1 is to bind a plurality of sheets discharged from an image forming apparatus into a sheet bundle, and to bind with this binding means. A tray that ejects the bundle of paper
In a sheet post-processing apparatus having a discharging unit for discharging the bundle of sheets bound by the binding unit and a discharging unit for discharging the bundle of sheets discharged from the discharging unit to the tray, sheets of different sizes are The sheet bundle discharging linear velocity of the discharging unit and the sheet bundle discharging linear velocity of the sheet discharging unit are the same when the mixed sheet bundle is discharged to the tray.

According to a second aspect of the invention, in the sheet post-processing apparatus according to the first aspect, there is provided a control means for changing the discharging operation stop position of the discharging means when discharging the sheet bundle according to the number of sheets in the sheet bundle. Is.

According to a third aspect of the present invention, in the sheet post-processing apparatus according to the first aspect, there is provided a control means for changing the discharging operation stop position of the discharging means when discharging the sheet bundle according to the sheet size of the sheet bundle. Is.

According to a fourth aspect of the present invention, in the sheet post-processing apparatus according to the first aspect, there is provided control means for changing the discharging operation stop position of the discharging means when discharging the sheet bundle according to the number of sheets and the sheet size of the sheet bundle. Be prepared.

[0013]

1 shows an embodiment of the present invention. In the sheet post-processing apparatus 1 of this embodiment, an inlet sensor 3 serving as a sheet detection unit for detecting a sheet is provided at an inlet portion of a sheet conveyance path into which an image-formed sheet discharged from the image forming apparatus 2 is carried. Roller 4 and branch claw 5,
6 is provided. The branch claws 5 and 6 transfer the paper from the image forming apparatus to the paper discharge tray 7, the paper to the paper discharge tray 8, and the paper to the stapling device 9 as a binding unit. And a transport path switching means that is divided into

From the entrance of the sheet post-processing apparatus 1 to the sheet discharge tray 8
In the conveying path for conveying the paper in the direction of
A sheet discharge sensor 11 as a sheet detection unit that detects the sheet discharged to the sheet discharge tray 5, a sheet discharge roller 12 that constitutes the sheet discharge unit, and the like are arranged. Further, a paper surface lever 13 that moves up and down depending on the stacked sheets on the discharge tray 8, a shift roller 14 that shifts the sheets to one side in the width direction, and a sensor 15 as a detection unit that detects the height of the stacked sheets on the discharge tray 8. , 16
Is provided.

In the conveying path for conveying the sheet from the entrance of the sheet post-processing apparatus 1 toward the stapling apparatus 9, the conveying roller 1 is provided.
7, a paper discharge sensor 18 as a paper detection unit for detecting the paper discharged to the stapling device 9, and a brush roller 19 as a paper feed roller. A conveying roller 20 is arranged in the conveying path between the entrance roller 4 and the branching claw 5, and a conveying roller 21 and a discharging roller 22 are arranged in the conveying path between the branching claw 5 and the paper discharge tray 7. There is.

The stapling device 9 includes a staple tray 23.
The staple tray 23 is provided on the lower side (see FIG. 3).
Is a jogger fence 24 that constitutes a jogger unit that aligns sheets in the direction perpendicular to the sheet transport direction, and a return roller 2 that aligns sheets in the sheet transport direction.
5 is arranged, and at the position behind the jogger fence 24, a discharge belt 26, which constitutes a discharging means for discharging the bound sheet bundle, is arranged. The brush roller 19 presses the downward bending of the sheet bundle, and the discharge belt home sensor 27 detects that the discharge belt 26 is located at the home position.

As shown in FIG. 2, the jogger fence 24 is driven by a jogger motor 28 via a jogger belt 29, and the return roller 25 is driven by a return solenoid 30 to perform a pendulum motion.
Below the jogger fence 24, as shown in FIGS. 3 and 4, a trailing edge fence 31 for abutting a sheet is provided.

As shown in FIG. 4, the stapling device 9 is laterally moved by being driven by a stapler (stapling device) moving motor 32 via a staple belt 33. The discharge sensor 18 detects the trailing edge of the paper and immediately
An ON command is issued to the return solenoid 30 to return the roller 25.
The return roller 25 is arranged at a position where it can hit the trailing edge of the sheet even when is operated.

As shown in FIG. 5, the discharging belt 26 has the discharging claw 26a fixed and is driven by the discharging motor 34 to rotate. As shown in FIG. 6, the paper discharge tray 8 is suspended from the upper and lower lift belts 35 and provided so as to be movable in the vertical direction. The vertical lift belt 35 is connected to a pulley of a vertical motor 37 via a transmission mechanism 36 including a gear train and a timing belt, and the forward / reverse rotation of the vertical motor 37 causes the paper discharge tray 8 to rise or descend. The paper discharge tray moving means includes the vertical lift belt 35, the transmission mechanism 36, the vertical motor 37, and a motor driver 38 and a CPU 39, which will be described later, for controlling the driving of the vertical motor 37.
(See FIG. 8).

When the discharge tray 8 is full of paper, this is detected by the lower limit sensor 40. When the catch roller 14 is pushed up by the paper ejection tray 8 when the paper ejection tray 8 is raised, the lower limit sensor 40 is turned off, and the vertical motor 37 stops rotating to prevent damage to the paper ejection tray 8 due to overrun. .

FIG. 7 shows a portion for detecting the height of the paper 41 on the paper discharge tray 8. The paper lever 13 is used for the paper ejection tray 8
Is provided near the discharge port for discharging the paper to the shaft 42
Is rotatably supported by. The tip of the paper surface lever 13 contacts the uppermost surface of the paper 41 on the paper discharge tray 8. The paper surface lever 13 rotates according to the height of the paper sheet 41 on the paper ejection tray 8, and the sensors 15 and 16 are turned on / off near the root of the paper surface lever 13 to set the height of the paper sheet 41 on the paper ejection tray 8. To detect.

The sensor 16 is used as a sensor for generating a signal when the discharge tray 8 should be lowered.
Reference numeral 5 is used as a sensor that generates a signal when the paper discharge tray 8 should be raised. The paper discharge tray 8 is moved up and down by the paper discharge tray moving means in correspondence with the stack amount of the paper, and the sensor 16 detects that the uppermost surface of the paper 41 on the paper discharge tray 8 has reached a predetermined height. When the sensor 16 is turned on (the sensor 16 is turned on), the paper ejection tray 8 is driven by the vertical motor 37 and is lowered. When the sensor 16 is turned off, the paper ejection tray 8 is stopped and the paper surface lever 13 is lowered to a specified position. Stop.

When the sensor 15 detects that the paper 41 on the paper ejection tray 8 has been completely removed and the upper surface of the paper ejection tray 8 has dropped to a position lower than the specified position (the sensor 15 is turned on), the paper is ejected. The paper tray 8 is driven by the vertical motor 37 to move up, and when the sensor 15 is turned off, the paper discharge tray 8 is stopped to move up to the specified position.

That is, when the sensor 16 is turned on, the CPU 39 causes the vertical motor 37 to lower the paper output tray 8, and when the sensor 16 is turned off, the vertical motor 37 is stopped to stop the paper output tray 8. Further, the CPU 39 uses the sensor 1
When the sensor 5 is turned on, the paper output tray 8 is raised by the vertical motor 37, and when the sensor 15 is turned off, the vertical motor 37 is stopped to stop the paper output tray 8 and the vertical motor 3
Raise 7 to the specified position.

FIG. 8 shows the electrical system of this embodiment. Each switch and each sensor (sensor 15, 16,
Signals from the sensors 3, 11, 18 (including the discharge belt home sensor 27) 43 are input to the CPU 39 as a control means via the buffer 44 and the I / O interface 45. The CPU 39 controls the vertical motor 37 and the shift motor 46 to be motor drivers 38, 47 according to the input signal.
, The sheet discharge motor 48 is controlled via the stepping motor control device 49, the staple motor 50 is controlled via the I / O interface 45 and the motor driver 51, the carry motor 52 is controlled, and the discharge motor is controlled. 34
Is controlled via the I / O interface 45 and the servo control circuit 53, the stapler moving motor 32 and the jogger motor 28 are controlled via the I / O interface 45 and the stepping motor control devices 54 and 55, and the branch solenoid 56 and the return solenoid are returned. Solenoid 30 driver 57, 5
Control via 8

The shift motor 46 drives the paper discharge tray 8 in the lateral direction perpendicular to the paper discharge direction, and the stapling device 9 is driven by the staple motor 50 and the stapler moving motor 32. The paper discharge motor 48 rotationally drives the paper discharge rollers 12 and 22, and the carry motor 52 drives the carry rollers 10 and 17.
20 and 21 are rotationally driven. The discharge motor 34 rotationally drives the discharge belt 26, and the discharge belt 26 and the discharge motor 3 are driven.
A discharging unit 4 discharges the bundle of sheets bound by the stapling device 9 to the discharge roller 12.

The jogger motor 28 is used for the jogger fence 2
4, the branch solenoid 56 drives the branch claws 5 and 6 to switch the paper conveyance direction, and the return solenoid 30 drives the return roller 25. The CPU 39 uses the carry motor 5
The pulse signal input from 2 according to the rotation amount is counted, and the return solenoid 30 is controlled according to the count value. The matching control means are the CPU 39 and the CPU 3.
It is made up of various operation programs for moving 9.

In the sheet post-processing apparatus 1 of this embodiment, the CPU 39 controls each load in response to an input signal to perform the following operation. That is, when the mode for discharging the paper to the paper discharge tray 7 is selected, the image-formed paper discharged from the image forming apparatus 2 is received by the entrance roller 4 and the conveyance path is discharged by the branching claw 5. It is switched to the paper tray 7 side and the transport roller 2
1 is carried, and the paper is ejected by the paper ejection roller 22 to the paper ejection tray 7
Is discharged to.

When the non-staple mode in which the sheets are not bound is selected by the mode selecting means,
The image-formed sheet discharged from the image forming apparatus 2 is
It is received by the entrance roller 4, and the conveying path is switched to the sheet discharge tray 8 side by the branching claws 5 and 6 to convey the conveying roller 1.
The sheet is conveyed by 0, is aligned in the longitudinal direction of the sheet by the shifting roller 14, and is stacked on the sheet discharge tray 8 by the sheet discharge roller 12. The paper discharge sensor 11 detects the paper discharged to the paper discharge tray 8. At this time, the approach roller 14 is decelerated when the paper discharge sensor 11 detects the trailing edge of the paper, and the paper stackability of the paper discharge tray 8 is improved.

When the paper is sequentially discharged to the paper discharge tray 8, the paper surface lever 13 rotates according to the height of the paper on the paper discharge tray 8, and the sensors 15 and 16 cause the paper surface lever 1 to move.
The height of the paper on the paper discharge tray 8 is detected by being turned on / off near the root of the sheet 3. The paper discharge tray 8 is moved up and down by the vertical motor 37 in accordance with the stack amount of paper to be maintained at an appropriate height.

When the sorting mode or the stacking mode is selected by the mode selecting means, the CPU 39 shifts the sheet discharge tray 8 to the left or right by the shift motor 46 in response to the sorting signal output from the control panel of the apparatus main body, and the sheet until the end of the job. Sort. Also, C
The PU 39 lowers the discharge tray 8 by 30 mm by the vertical motor 37 at the end of the job.

When the stapling mode for binding sheets is selected by the mode selecting means, the jogger fence 24, as shown in FIG.
Is moved from the home position, and stands by at a position 7 mm away from the paper width on one side. The paper size signal indicating the paper size is sent from the image forming apparatus 2 to the CPU 49 at the time of starting a job and every time the paper is discharged from the image forming apparatus 2. The CPU 49 indicates the movement distance of the jogger fence 24 or the like. It is determined by the paper size signal sent when the job is started.

The sheet discharged from the image forming apparatus 2 passes through the inlet roller 4, the conveying path is switched to the stapling apparatus 9 side by the branching claws 5 and 6, the sheet is conveyed by the conveying roller 17, and is discharged to the staple tray 23. It The paper discharge sensor 18 detects the paper discharged to the staple tray 23.

When the trailing edge of the paper passes through the paper discharge sensor 18, the jogger fence 24 is driven by the jogger motor 28 to perform jogging (reciprocating movement in the direction of the arrow in the figure) inward by 5 mm from the standby position. Further, the paper discharge sensor 18 detects when the trailing edge of the paper passes and detects the signal as C
Input to PU39. The CPU 39 starts the transmission pulse from the carry motor 52 (the carry motor 5 from the time when the signal is received).
The number of pulses corresponding to the rotation amount of 2) is counted, a predetermined number of transmission pulses are transmitted, and when the count value reaches a predetermined value, the return solenoid 30 is turned on.

The return roller 25 performs a pendulum motion by turning the return solenoid 30 on and off.
When is ON, the paper is hit and returned in the downward direction, and the paper is abutted against the trailing edge fence 31 to align the paper vertically. This time,
Each time the paper stored in the staple tray 23 passes through the paper discharge sensor 18 as an entrance sensor and is detected, the signal is input to the CPU 39, and the CPU 39 counts the signal to count the number of paper. .

After the return solenoid 30 is turned off and a predetermined time has passed, the jogger fence 24 is driven by the jogger motor 28 to move inward by 2 mm and temporarily stopped, and the horizontal alignment of the sheets is completed. After that, the jogger fence 24 is driven by the jogger motor 28 to reach 7 m.
Go back and wait for the next sheet. When the trailing edge of the sheet of the last page (the sheet that becomes the last page of the sheet bundle) passes the sheet ejection sensor 18,
The jogger fence 24 again jogs 5 mm inward from the standby position to prepare for the binding operation of the sheet bundle.

After that, when a predetermined time elapses, the stapling device 9 is operated to bind the end portion of the sheet bundle in the staple tray 23 with a staple. At this time, if the binding of a plurality of sheet bundles is designated, the CPU 399 causes the stapler moving motor 32 to properly move the stapling device 9 along the trailing edge of the sheet bundle after the binding process of one portion of the sheet bundle is completed. The stapler 9 is moved to the position, and the stapling device 9 is caused to perform the binding process for the second position of the sheet bundle. In this way, binding of a plurality of paper bundles is sequentially performed.

When the binding process for the sheet bundle is completed, the ejection motor 34 drives the ejection belt 26. Further, the paper discharge motor 48 also operates at the same time to drive the paper discharge roller 12, the discharge claw 26a of the discharge belt 26 lifts the sheet bundle in the staple tray 23, and the discharge roller 12 receives the sheet bundle and discharges it. The paper is discharged to the paper tray 8. At this time, CPU
39 controls the discharge motor 34 and the discharge motor 48 to set the relationship between the linear velocity of the discharge belt 26 and the linear velocity of the discharge roller 12 such that the linear velocity of the discharge belt 26> the linear velocity of the discharge roller 12.

The above series of operations is repeated until the last job.

In the present embodiment, as described above, the paper size signal is sent from the image forming apparatus 2 to the CPU 3 each time the paper is discharged from the image forming apparatus 2 in addition to the start of the job.
It is sent to 9. Therefore, the CPU 39 stores the size of the paper accommodated in the staple tray 23 by storing the paper size signal from the image forming apparatus 2 in the memory, and binds the paper accommodated in the staple tray 23. At the time of discharging after processing, it is checked whether the bundle of sheets is a mixture of sheets of different sizes.

When the sheet bundle is a mixture of sheets of different sizes, the CPU 39 sets the discharge motor 34 and the discharge motor 48 to the linear velocity of the discharge belt 26 and the discharge roller 12.
The linear velocity is controlled to be the same. The CPU 39
The discharging motor 34 is stopped so that the discharging claw 26a for picking up the sheet may stop at an appropriate position depending on the sheet size and the number of sheets of the sheet bundle (when the sheet bundle is a sheet bundle in which sheets of different sizes are mixed, it will be described later). Then, the bundle of sheets is discharged to the discharge tray 8 by the discharge rollers 12. After the discharge belt 26 is stopped, the sheet bundle is driven only by the sheet discharge rollers 12, so the speed of the sheet discharge rollers 12 can be adjusted, and control can be performed in consideration of the sheet stackability of the sheet discharge tray 8. .

FIG. 9 is a flow chart showing the processing flow of the CPU 39 in this embodiment. This flowchart is a main routine of a program for causing the CPU 39 to perform the series of operations described above. This main routine includes a series of subroutines for operating the sheet post-processing apparatus 1, a subroutine for stapling control, a subroutine for ejecting belt control (for mixed sheet sizes), a discharge roller control (for mixed sheet sizes) The CPU 39 executes the contents of the subroutine as needed.

FIG. 10 shows a portion for determining whether or not the sheet bundle is a sheet bundle in which sheets of different sizes are mixed in the subroutine for performing stapling control in the main routine. After executing processing such as binding of the sheets stored in the staple tray 23, the CPU 39 determines whether the bound sheet bundle is a sheet bundle in which sheets of different sizes are mixed, and the sheet bundle is If it is not a sheet bundle in which different sheets are mixed, normal sheet discharge belt 26 and sheet discharge and drive control of sheet discharge roller 12 are performed, that is, sheet bundle discharge and sheet discharge are performed as described above. The discharge motor 34 and the paper discharge motor 48 are controlled as described above. Also,
When the sheet bundle bound by the stapling device 9 is a sheet bundle in which sheets of different sizes are mixed, the CPU 39 sets the ejection belt drive job counter BELTJC to 1 and sets the discharge roller drive job counter EXITJC to 1. After setting, the subsequent processing is executed to exit the subroutine of FIG.

FIG. 11 shows a subroutine for controlling the discharge belt (when the paper sizes are mixed). In this subroutine, the CPU 39 executes a different subroutine depending on the value of BELTJC. That is, the CPU 39
When the value of LTJC is 0, the BELTJC0 subroutine is executed, and when the value of BELTJC is 1, B
The subroutine ELTJC1 is executed, and when the value of BELTJC is 2, the subroutine BELTJC2 is executed. When the control of the discharge belt 26 is unnecessary,
The value of BELTJC is 0, and as shown in FIG. 13, the CPU 39 returns and exits nothing in the subroutine of BELTJC0.

FIG. 12 shows a subroutine for carrying out the paper ejection roller control (when the paper sizes are mixed). In this subroutine, the CPU 39 executes a different subroutine depending on the value of EXITJC. That is, the CPU 39
If the ITJC value is 0, the EXITJC0 subroutine is executed, and if the EXITJC value is 1, E
Execute the subroutine of XITJC1 and do the same with EX
Execute a subroutine according to the ITJC value.

FIG. 14 shows the BELTJC1 subroutine. When the BELTJC is set to 1, the CPU 39 executes the BELTJC1 subroutine. In this subroutine, the CPU 39 first causes the discharge motor 34
Is driven so that the linear velocity of the discharge belt 26 and the linear velocity of the discharge roller 12 are the same, the number of sheets in the sheet bundle is checked from the count result of the number of sheets, and the distance for driving the discharge motor 34 ( The pulse set value indicating the distance by which the ejection claw 26a is moved from the current position) is changed depending on the number of sheets in the sheet bundle.

For example, the CPU 39 sets the pulse set value to A when the number of sheets in the sheet bundle is smaller than the set number, and sets the pulse set value to B which is larger than A when the number of sheets in the sheet bundle is equal to or larger than the set number. Here, the set number of sheets and the pulse set values A and B are set so that when a sheet bundle in which sheets of different sizes are mixed is ejected to the sheet ejection tray 8, buckling of the sheet in the vicinity of the sheet ejection roller 12 is eliminated. Is set.

The CPU 39 compares the number of sheets of the sheet bundle with a plurality of set numbers to determine which of a plurality of ranges the pulse number should be set to. It may be changed accordingly (for example, the pulse set value may be changed so as to increase as the number of sheets in the sheet bundle increases). After that, the CPU 39 causes the BEL
Set 2 to TJC and exit this routine.

FIG. 15 shows the BELTJC2 subroutine. When 2 is set in BELTJC, the CPU 39 executes the BELTJC2 subroutine. In this subroutine, the CPU 39 uses the pulse setting value
The number of pulses actually driving the discharge motor 34 is compared, and if the number of pulses actually driving the discharge motor 34 is less than the pulse set value, this routine is returned to exit the routine.

Further, the CPU 39 actually causes the discharge motor 3
When the number of pulses driving 4 reaches the pulse set value, the discharge motor 34 is stopped. The determination of the moving distance of the ejection pawl 26a based on the number of pulses driving the ejection motor 34 is performed by attaching an encoder to a stepping motor or a DC motor as the ejection motor 34 and counting the number of pulses from the encoder to determine the ejection pawl 26a. It can be realized by judging the moving distance.

Next, the CPU 39 sets BELTJC to 3 and exits this routine. CPU39 is BEL
BELT executed when TJC is set to 3 or later
In the subroutines after JC3, the discharge motor 34 is controlled in the same manner as the control of the discharge motor 34 after the discharge motor 34 is stopped, which is performed in a normal mode in which the paper bundle is not a stack of sheets of different sizes.

Next, each sub-routine in the sub-routine for performing the discharge belt control (when the paper sizes are mixed) will be described. When EXITJC is set to 1, the CPU 39 executes the subroutine of EXITJC1 shown in FIG. In this subroutine, the CPU 39 drives the paper discharge motor 48 so that the linear speed of the paper discharge roller 12 and the linear speed of the discharge belt 26 become the same, sets EXITJC to 2, and exits this routine. CPU39 is EXIT
EXITJ executed when JC is set to 2 or later
In the subroutine after C2, the discharge motor 48 is controlled in the same manner as the control of the discharge motor 48, which is performed in a normal mode in which the sheet bundle is not a sheet bundle in which sheets of different sizes are mixed.

In this embodiment, a stapling device 9 as a binding means for binding a plurality of sheets discharged from the image forming apparatus 2 into a sheet bundle, and a tray 8 for discharging the sheet bundle bound by the binding means. A discharging belt 26 as a discharging means for discharging the sheet bundle bound by the binding means, and a discharging roller 12 as a discharging means for discharging the sheet bundle discharged from the discharging means to the tray. In the sheet post-processing apparatus 1 having the above, the sheet bundle discharging linear velocity of the discharging unit and the sheet bundle discharging linear velocity of the sheet discharging unit when discharging the sheet bundle on which the sheets of different sizes are mixed to the tray are made the same. Therefore, when a sheet bundle in which sheets of different sizes are mixed is discharged to the tray, buckling of the sheet in the vicinity of the discharge roller 12 is eliminated, and the sheet bundle can be discharged reliably.

Further, in this embodiment, since the CPU 39 as the control means for changing the discharging operation stop position of the discharging means at the time of discharging the bundle of sheets according to the number of sheets of the bundle of sheets, the sheets of different sizes are mixedly mixed. When ejecting the bundle to the tray, the bundle of sheets can be reliably ejected, and the stackability of the sheets on the tray can be improved.

17 to 19 show subroutines executed by the CPU in another embodiment of the present invention. In this embodiment, the CPU 39 is similar to the above embodiment.
The subroutine shown in FIGS. 17 to 19 is executed instead of the subroutine shown in FIG. C
As shown in FIG. 17, the PU 39 returns upon exiting the BELTJC0 subroutine and does nothing.

When BELTJC is set to 1, the CPU 39 executes the BELTJC1 subroutine shown in FIG. In this subroutine, the CPU 39 first drives the discharge motor 34 so that the linear speed of the discharge belt 26 and the linear speed of the paper discharge roller 12 are the same, and checks the paper size of the paper stack from the paper size signal. Then, the pulse set value indicating the distance to drive the discharging motor 34 (the distance to move the discharging claw 26a from the current position) is changed according to the sheet size of the sheet bundle.

For example, the CPU 39 sets the pulse set value to A when the largest paper size of the paper bundles is smaller than the set size, and sets the pulse set value to A when the largest paper size of the paper bundle is equal to or larger than the set size. The set value is B which is larger than A. Here, the set size and the pulse set values A and B are set so that buckling of sheets near the sheet discharge roller 12 is eliminated when a sheet bundle in which sheets of different sizes are mixed is discharged to the sheet discharge tray 8. Is set.

The CPU 39 determines which of a plurality of ranges the sheet size of the sheet bundle is to be compared with a plurality of set sizes, and sets the pulse set value to the range of the sheet size of the largest sheet bundle. It may be changed depending on whether it enters (for example, the pulse setting value may be changed so as to increase as the size of the largest sheet in the sheet bundle increases). Thereafter, the CPU 39 sets 2 in BELTJC and exits this routine.

When the BELTJC is set to 2, the CPU 39 executes a BELTJC2 subroutine as shown in FIG. In this subroutine, the CPU 39
Compares the pulse set value with the number of pulses that actually drive the discharge motor 34, and if the number of pulses that actually drive the discharge motor 34 is less than the pulse set value, return to execute this routine. Get out.

Further, the CPU 39 actually causes the discharge motor 3
When the number of pulses driving 4 reaches the pulse set value, the discharge motor 34 is stopped. Next, the CPU 39 causes the BE
Set LTJC to 3 and exit this routine. CPU
39 is a subroutine executed after BELTJC3 is set to 3 or later in BELTJC3, which is a normal mode in which the sheet bundle is not a sheet bundle in which sheets of different sizes are mixed, and the discharge is performed after the discharge motor 34 is stopped. The discharge motor 34 is controlled similarly to the control of the motor 34.

This embodiment is based on the above embodiment.
CP as a control means for changing the discharging operation stop position of the discharging means at the time of discharging a bundle of sheets according to the sheet size of the sheet bundle
Since it has U39, it is possible to improve the stackability of the paper on the tray when ejecting the paper bundle in which different size papers are mixed to the tray. Can be prevented from falling.

20 to 22 show subroutines executed by the CPU in another embodiment of the present invention. In this embodiment, the CPU 39 is similar to the above embodiment.
20 to 22 are executed instead of the subroutine shown in FIG. C
As shown in FIG. 20, the PU 39 returns upon exiting the BELTJC0 subroutine and does nothing.

When the BELTJC is set to 1, the CPU 39 executes the BELTJC1 subroutine shown in FIG. In this subroutine, the CPU 39 first drives the ejection motor 34 so that the linear velocity of the ejection belt 26 and the linear velocity of the paper ejection roller 12 become the same, and from the result of counting the number of sheets and the paper size signal. The number of sheets and the sheet size of the sheet bundle are checked, and the pulse set value indicating the distance to drive the ejection motor 34 (the distance to move the ejection claw 26a from the current position) is changed depending on the number of sheets and the sheet size of the sheet bundle.

For example, the CPU 39 sets the pulse set value to A when the number of sheets in the sheet bundle is smaller than the set number and the largest sheet size in the sheet bundle is smaller than the set size, and the number of sheets in the sheet bundle is smaller than the set number. If the paper size is small and the largest paper size in the paper stack is equal to or larger than the set size, the pulse set value is set to B larger than A. Also, the CPU 39
If the number of sheets in the sheet bundle is equal to or larger than the set number and the largest sheet size of the sheet bundle is smaller than the set size, the pulse set value is set to C larger than B, and the number of sheets in the sheet bundle is equal to or larger than the set number. If the largest sheet size of the sheet bundle is equal to or larger than the set size, the pulse set value is set to D larger than C. Here, the set size and pulse set values A to D are set so that when a sheet bundle in which sheets of different sizes are mixed is discharged to the discharge tray 8, the buckling of the sheet near the discharge roller 12 is eliminated. Is set.

The CPU 39 compares the number of sheets in the sheet bundle and the largest sheet size with a plurality of set numbers and a plurality of set sizes, respectively, and determines which of a plurality of ranges the pulse set value is set. It may be changed according to the determination result (for example, the pulse set value may be changed so as to increase as the number of sheets in the sheet bundle increases and increase as the largest sheet size of the sheet bundle increases). . After that, the CPU 39 sends 2 to BELTJC.
To exit this routine.

When 2 is set in BELTJC, the CPU 39 executes a subroutine of BELTJC2 as shown in FIG. In this subroutine, the CPU 39
Compares the pulse set value with the number of pulses that actually drive the discharge motor 34, and if the number of pulses that actually drive the discharge motor 34 is less than the pulse set value, return to execute this routine. Get out.

Further, the CPU 39 actually causes the discharge motor 3
When the number of pulses driving 4 reaches the pulse set value, the discharge motor 34 is stopped. Next, the CPU 39 causes the BE
Set LTJC to 3 and exit this routine. CPU
39 is a subroutine after BELTJC3 that is executed when BELTJC is set to 3 or later. The control is performed in a normal mode in which the sheet bundle is not a sheet bundle in which different size sheets are mixed. Perform the same control as.

This embodiment is based on the above embodiment.
Since the CPU 39 is provided as the control means for changing the discharging operation stop position of the discharging means at the time of discharging the sheet bundle depending on the number of sheets and the sheet size of the sheet bundle, when discharging the sheet bundle in which the sheets of different sizes are mixed, to the tray. The stack of sheets can be reliably discharged, the stackability of sheets on the tray can be improved, and the stack of sheets, which tends to occur when the sheet size is large, can be prevented from falling from the tray. .

[0069]

As described above, according to the first aspect of the present invention, with the above-described structure, the sheet bundle can be reliably discharged when the sheet bundle having the different size sheets mixed is discharged to the tray. .

According to the second aspect of the present invention, with the above configuration, when the sheet bundle in which different-sized sheets are mixed is discharged to the tray, the sheet bundle can be reliably discharged, and the sheet on the tray is also discharged. The stackability of can be improved.

According to the third aspect of the present invention, with the above configuration, it is possible to improve the stackability of the sheets on the tray when discharging the sheet bundle in which the sheets of different sizes are mixed to the tray, and the sheet size is reduced. It is possible to prevent a stack of sheets, which tends to occur when the size is large, from falling from the tray.

According to the fourth aspect of the present invention, with the above configuration, when the sheet bundle in which sheets of different sizes are mixed is discharged to the tray, the sheet bundle can be reliably discharged, and the sheet on the tray is also discharged. It is possible to improve the stackability of the sheet and prevent the stack of sheets from falling from the tray, which tends to occur when the sheet size is large.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of the present invention.

FIG. 2 is a perspective view showing the vicinity of the jogger fence / return roller drive unit of the same embodiment.

FIG. 3 is a side view showing the vicinity of the lower side of the jogger fence of the same embodiment.

FIG. 4 is a perspective view showing a stapling device drive portion of the same embodiment.

FIG. 5 is a perspective view showing the vicinity of the discharging means of the same embodiment.

FIG. 6 is a schematic view showing a discharge tray moving unit of the same embodiment.

FIG. 7 is a schematic view showing a portion for detecting the height of the recording paper on the paper discharge tray of the embodiment.

FIG. 8 is a block diagram showing an electrical system of the same embodiment.

FIG. 9 is a flowchart showing a main routine executed by a CPU in the same embodiment.

FIG. 10 is a flowchart showing a subroutine of stapling control executed by the CPU.

FIG. 11 is a flowchart showing a subroutine of a discharge belt control executed by the CPU.

FIG. 12 is a flowchart showing a subroutine of paper discharge roller control executed by the CPU.

FIG. 13 is a flowchart showing a BELTJC0 subroutine executed by the CPU.

FIG. 14 is a flowchart showing a BELTJC1 subroutine executed by the CPU.

FIG. 15 is a flowchart showing a BELTJC2 subroutine executed by the CPU.

FIG. 16 is a flowchart showing a subroutine of EXITJC1 executed by the CPU.

FIG. 17 is a flowchart showing a BELTJC0 subroutine executed by a CPU according to another embodiment of the present invention.

FIG. 18 is a flowchart showing a BELTJC1 subroutine executed by the CPU.

FIG. 19 is a flowchart showing a BELTJC2 subroutine executed by the CPU.

FIG. 20 is a flowchart showing a BELTJC0 subroutine executed by a CPU according to another embodiment of the present invention.

FIG. 21 is a flowchart showing a BELTJC1 subroutine executed by the CPU.

FIG. 22 is a flowchart showing a subroutine of BELTJC2 executed by the CPU.

[Explanation of symbols]

9 Staple device 8 trays 26 release belt 12 Paper ejection roller 39 CPU

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Masahiro Tamura             1-3-3 Nakamagome, Ota-ku, Tokyo, stock             Company Ricoh (72) Inventor Junichi Iida             1-3-3 Nakamagome, Ota-ku, Tokyo, stock             Company Ricoh (72) Inventor Nobuyoshi Suzuki             1-3-3 Nakamagome, Ota-ku, Tokyo, stock             Company Ricoh F term (reference) 2H072 AA04 AA16 AA17 AA23 AA24                       AB13 GA08 HA03 HA06 HB05                       JA02 JA03                 3F108 GA02 GA03 GA04 GB01 HA02                       HA39 HA45 HA46 HA54

Claims (4)

[Claims] 1. A binding unit that binds a plurality of sheets discharged from an image forming apparatus into a sheet bundle, a tray that discharges the sheet bundle bound by the binding unit, and a sheet bound by the binding unit. In a sheet post-processing device having a discharging means for discharging a bundle and a discharging means for discharging the sheet bundle discharged from the discharging means to the tray, a sheet bundle in which different-sized sheets are mixed is loaded on the tray. A sheet post-processing apparatus, wherein the sheet bundle discharging linear velocity of the discharging unit and the sheet bundle discharging linear velocity of the sheet discharging unit are the same when discharging. 2. The sheet post-processing apparatus according to claim 1,
A sheet post-processing apparatus comprising: a control unit that changes a discharging operation stop position of the discharging unit when a sheet bundle is discharged according to the number of sheets in the sheet bundle. 3. The sheet post-processing apparatus according to claim 1,
A sheet post-processing apparatus comprising: a control unit that changes a discharging operation stop position of the discharging unit when a sheet bundle is discharged according to a sheet size of the sheet bundle. 4. The sheet post-processing apparatus according to claim 1,
A sheet post-processing apparatus comprising: a control unit that changes a discharging operation stop position of the discharging unit when discharging a sheet bundle according to the number of sheets and the sheet size of the sheet bundle.