JPH0826569A - Aftertreatment device for sheet - Google Patents

Abstract

PURPOSE:To stack the specified number of sheet sheaves positively on a discharge tray at the time of a staple mode by providing a control means for changing the stacking face height of the discharge tray from the first sheaf to the second sheaf onward at the time of discharging the stapled sheaves of sheets onto the discharge tray. CONSTITUTION:In an aftertreatment device for sheet provided with a stapler for stapling plural sheets, and a vertically movable discharge tray 12 for stacking true stapled sheaves of sheets, it is so controlled that the placing face of the discharge tray 12 is temporarily moved up every discharge of a sheaf of sheets at the time of discharging sheaves of sheets onto a discharge tray 12. The discharge tray 12 thereby stands by always in a high position (a position almost in contact with a drawing roller 7) at the time of discharging a sheaf of sheets, and the hanging and arrival angle theta of a sheaf of sheets are reduced to prevent the generation of peeling when the tip of the sheaf of sheets slips. The discharge tray 12 is lowered almost at the same time as the discharge of the sheaf of sheets, so that the sheaf of sheets can be positively stacked on the discharge tray 12.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a binding means for receiving sheets discharged from an upstream image forming apparatus and binding a plurality of sheets, and a vertically movable sheet discharge tray for stacking the bound sheet bundle. The present invention relates to a sheet post-processing device that includes

[0002]

2. Description of the Related Art Binding means (stapler) for aligning a plurality of copied sheets and stacking them (stapling)
A paper post-processing device having a sheet has been widely proposed.

[0003]

FIGS. 43 (a), 43 (b) and 43 (c) are schematic views for explaining the first problem of the conventional example.
In the staple mode, unlike the non-staple mode, a bundle of sheets (in the case of binding 50 sheets, the thickness is generally about 6 to 7 mm) is discharged, so the position of the discharge tray 12 should be lowered. However, it is not possible to stack the rear end of the sheet bundle along the back fence 15 for orderly and stable stacking. However, if the position of the paper discharge tray 12 is set low when discharging a bundle of paper, the paper will be discharged with its tip hanging down [see (a) of the same figure].
In particular, the first copy is discharged while the center of the stack of sheets is bent due to the contact resistance with the discharge tray 12 at that time. In this way, the sheet bundle discharged onto the sheet discharge tray 12 in a bent state slides on the inclined surface of the sheet discharge tray 12 formed of plastic and stops there without reaching the back fence 15. There is a tendency for this to occur [see (b) of the same figure]. The second and subsequent sets of sheets are ejected while sliding on the already ejected sheet bundle with the leading edge sliding, and due to friction between the sheets, the deflection may not occur and the sheets may slide down to the back fence 15. it can. However, the first copy stops on the way without slipping down to the back fence 15, and as a result, accurate loading cannot be performed [see FIG. In addition,
Reference numeral 3 is a discharge roller, and 7 is an approach roller.

FIGS. 44 (a), 44 (b) and 44 (c) are schematic views for explaining the second problem of the conventional example. As described above, the position of the paper discharge tray 12 must be lowered in the staple mode, but there are other problems caused by lowering the paper discharge tray 12. This is because when the leading edge of the sheet bundle hangs down and is ejected, when the bottom 1 to 3 sheets of the sheet bundle lands, sometimes a phenomenon of bending occurs, which causes a curled and unstable loading surface. (Refer to (a) and (b) in the same figure], if a stack of sheets is sequentially stacked on it, it falls from the discharge tray 12 or becomes bulky and cannot be secured a predetermined stacking amount. Occurs (see (c) in the figure). This would look ugly and it would be a pain to correct the bend later. Such a problem remarkably occurs when the curl of the paper is downward and large.

The present invention has been made on the basis of such a background, and an object thereof is to provide a sheet post-processing apparatus capable of reliably stacking a predetermined number of sheet bundles in a staple mode on a sheet discharge tray. And

[0006]

The above-mentioned object is to receive a sheet discharged from an image forming apparatus on the upstream side and bind it to a plurality of sheets, and a vertically movable sheet discharge stacking the bound sheet bundle. In a sheet post-processing apparatus including a tray, when ejecting a bound sheet bundle onto a sheet ejection tray,
This is achieved by the first means having a control means for changing the stacking surface height of the discharge tray between the first copy and the second and subsequent copies.

Further, in the first means, it is achieved by the second means which makes the stacking surface height higher than the others only when the first set of sheet bundle is discharged.

Further, a sheet post-processing including a binding means for receiving the sheets discharged from the image forming apparatus on the upstream side and binding a plurality of sheets, and a vertically movable sheet discharge tray for stacking the bound sheet bundle. This is achieved by the third means provided with a control means for temporarily raising the stacking surface of the sheet discharge tray each time the sheet bundle is discharged when the bound sheet bundle is discharged onto the sheet discharge tray.

In the first and third means, the control means is a paper surface detection lever, two sensors for detecting the swing displacement of the paper surface detection lever, and the output of the sensor moves the paper discharge tray up and down. This is achieved by the fourth means composed of a vertical motor.

[0010]

In the first and second means, (a) of FIG. 41 is used.
As shown in, the paper ejection tray 12 is kept on standby only when the first set of paper is ejected. Then, the landing angle θ becomes small, and the sliding resistance between the front end of the sheet bundle and the sheet discharge tray 12 becomes small, so that the front end of the sheet bundle smoothly slides on the sheet discharge tray 12. Therefore, as shown in FIG. 6B, the sheet bundle is not bent and the back fence 15
Accurately slide down.

Next, as shown in FIG. 3C, when the sheet discharge tray 12 is lowered at the timing when the first set of sheet bundles have finished passing through the discharge rollers 3, the stacking surfaces of the second and subsequent sets are lowered. However, since the sliding frictional resistance is reduced due to the contact between the sheets, the sheet bundle is smoothly discharged, completely slides down to the back fence 15, and is stacked orderly on the sheet discharge tray 12.

In the third means, as shown in FIG. 42 (a), the sheet discharge tray 12 is always kept in a high position when the sheet bundle is discharged. Then, since the position of the stacking surface becomes high, the drooping of the sheet bundle is small, and the landing angle θ is also small. Therefore, when the leading edge of the sheet bundle slips, the curling is less likely to occur. The height of the stacking surface is set to a position where it is almost in contact with the shifting roller 7.

Next, as shown in FIG. 3B, the sheet discharge tray 12 is lowered at about the same timing as the sheet bundle discharge until the space between the shifting roller 7 and the stacking surface becomes about 10 to 15 mm. Therefore, the discharged sheet bundle can smoothly slide down on the back fence 15.

After that, as shown in FIG. 3C, the paper discharge tray 12 is again raised to a position where the stacking surface is almost in contact with the shifting roller 7, and the next paper stack is discharged as described above.

As described above, the stacking amount of the sheet bundle can be secured by repeating the vertical movement of the sheet discharge tray 12.

In the fourth means, the control means has a simple structure in order to simplify the mechanism and reduce the cost.

[0017]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is an overall configuration diagram of a post-processing device according to an embodiment, FIGS. 2 and 3 are configuration diagrams showing an operating state of a branch claw portion, FIG. 4 is a perspective view of a tray up-and-down mechanism, and FIG. 6, FIG. 6 is an explanatory view of the shifting roller portion, FIG. 7 is a perspective view of the tray shift mechanism, FIG. 8 is a perspective view of a main part of the tray shift mechanism, and FIGS. 9 and 10 are configuration diagrams showing an operating state of the tray shift mechanism. 11, FIG. 11 is a perspective view of the paper alignment mechanism, FIG. 12 is a configuration diagram of a main part of the paper alignment mechanism, FIG. 13 is a perspective view of a stapler moving mechanism, FIG. 14 is a perspective view of a discharge belt mechanism, and FIG. 15 is a discharge belt mechanism. FIG. 16 is a perspective view showing a main part perspective view, FIG. 16 is a perspective view showing a discharge unit drive mechanism, FIG. 17 is a perspective view showing a discharge unit drive mechanism, FIG. 18 is an overall control block diagram of a post-processing apparatus according to an embodiment of the present invention, and FIG. Is the control flow chart of the tray home set, 20 is a control flow chart of tray down during copying, FIGS. 21 to 25 are flow charts showing tray control in shift mode, FIG. 26 is a flow chart of subroutine of shift mode tray control, FIG. 27 is a flow chart of staple mode tray control, and FIG. 32 to 32 are flowcharts of a staple mode tray control subroutine, FIG. 33 is a flowchart of discharge control, FIGS. 34 to 40 are flowcharts of a discharge control subroutine, and FIGS. 41 (a) to 41 (c) are the first embodiment of the present invention. 42 is a schematic diagram showing the control contents of FIG.
(A) thru | or (c) are schematic diagrams which show the 2nd control content of this invention.

First, a general description of the entire system will be given with reference to the drawings. In these figures, 1
Is an inlet roller, 2 is an upper conveying roller group, 3 is a discharging roller which is a discharging means, 4 is a lower conveying roller group, 5 is a returning roller,
6 is a brush roller, 7 is a moving roller, 8 is a branching claw, 9 is a jogger fence, 10 is a discharging belt as a discharging means,
Reference numeral 11 is a stapler, 12 is a paper ejection tray (hereinafter referred to as tray), 13 is a paper lever, 14 is a shift cam, 15 is a back fence, 16 is a pin, 17 is a release claw, 18 is a vertical actuator, and 19 is a rear end fence. , 21 is a transport motor, 22 is a discharge motor, 23 is a vertical motor, 24 is a shift motor, 25 is a discharge motor, 26 is a jogger motor, 27 is a stapler moving motor, 29 is a branch solenoid, 30 is a return solenoid, and 31 is an upper limit. Switch, 32
Is a first paper surface sensor, 33 is a second paper surface sensor, 34 is a lower limit sensor, 35 is a shift sensor, 36 is an inlet sensor,
37 is a paper discharge sensor, 38 is a paper discharge sensor, 39 is a paper presence sensor, 40 is a discharging claw home position sensor, 41 is a stapler home position sensor, 45 is a main transport belt, 46 is an upper transport belt, 47 is a lower transport belt, 48
Is a vertical lift belt, 49 is a jogger belt, 50 is a stapler moving belt, 51 is a stapler unit, and 52 is a stapler unit.
Is a paper discharge roller, and 53 is a staple tray.

Next, the general operation will be described. The post-processing apparatus A is connected to a copying machine (image forming apparatus) provided on the right side (upstream side) in FIG. 1, for example, with a known automatic document feeder (RDH). The recording paper ejected from the copying machine is guided to the stapler unit 51 side by the branching claw 8 and conveyed to the paper ejection roller 52 by the lower conveying roller group 4. The recording paper that has been conveyed to the paper discharge roller 52 is discharged to the staple tray 53 by the paper discharge roller 52.
Is discharged to. Then, as many copies (recording sheets on which images have been recorded) as the number of originals set on the RDH are stacked on the staple tray 53 of the stapler unit 51. After stacking, the copies are stapled by the stapler 11. After the stapling operation, the discharge belt 10
The discharge motor 25 for driving the
The bundle of stapled recording paper is conveyed to the discharge roller 3. The bundle of recording sheets conveyed to the discharge roller 3 is discharged to the tray 12 by the discharge roller 3.

By the way, since the recording paper ejected to the staple tray 53 by the paper ejection roller 52 is vigorous,
As described above, particularly in the case of a large size paper, the upper end of the recording paper may be gripped by the discharge roller 3.

According to the present invention, the discharge belt 1 depends on the size of the recording paper discharged from the copying machine (in the case of large size paper).
The 0 claw 17 stands by in the vicinity of the discharge roller 3.

While the recording paper is being ejected to the stapler unit 51 by the ejection roller 52, the pawl 17 of the ejection belt 10 is made to stand by in the vicinity of the ejection roller 3 so that the recording paper is ejected to the stapler unit 51. While discharging, the claw 17 of the discharging belt 10 functions as a stopper for the discharged recording paper, so that the upper end of the recording paper cannot be held in the nip of the discharging roller 3 and It is possible to eliminate the presence of recording paper that is not stapled therein.

Next, each unit will be described. First, the branch claw shown in FIGS. 2 and 3 will be described. The branch claw 8 is connected to the branch solenoid 29 via the arm 70, and the path can be changed by turning the branch solenoid 29 on and off. Reference numerals 71 and 72 denote springs that hold the branch claw 8 on one path side by turning on and off the branch solenoid 29. Then, when the branch solenoid 29 is off (FIG. 2), the recording paper is fed to the upper transport path, and when it is on (FIG. 3), the recording paper is transported to the lower transport path.

Next, the tray lifting mechanism shown in FIGS. 4, 5 and 6 will be described. The tray 12 has a vertical lift belt 48.
The upper and lower lift belts 48 are driven by the upper and lower motors 23 via a gear train and a timing belt, and are raised and lowered by the forward and reverse rotations of the vertical motors 23. The home position of the tray 12 and the tray height during operation are detected by the paper surface lever 13 and the first and second paper surface sensors 32 and 33 shown in FIG. The paper surface lever 13 is pivotally supported by a shaft 73, and when the paper surface lever 13 rotates, the paper surface lever 13 is detected by the first and second paper surface sensors 32 or 33 (shown by a solid line or a broken line in FIG. 5). position).

The fullness of the tray 12 is detected by detecting the vertical actuator 18 by the lower limit sensor 34. Further, as shown in FIG.
5 is supported by an arm 74 pivotally supported by
The upper limit switch 31 is turned on / off by turning 4 (solid line and broken line positions shown in FIG. 6). Tray 1
When the shifting roller 7 is pushed up by the tray 12 during the ascending of 2 (the position shown by the solid line in FIG. 6), the upper limit switch 3
1, the up circuit of the vertical motor 23 is turned off. This prevents damage to the machine due to overrun of the tray 12.

Next, the tray shift mechanism shown in FIGS. 7, 8, 9 and 10 will be described.

The tray 12 is slidably assembled as described above, and by sliding the back fence 15 by the shift motor 24, the tray 12 is structured so as to slide in synchronization with the back fence 15. There is. A pin 16 is fixed to the back fence 15 as shown in FIGS. 9 and 10, and the pin 16 moves along the cam surface 14a of the shift cam 14 to change the rotational movement of the shift cam 14 into a linear movement, thereby making the back fence 15 15 is slid (FIGS. 9 and 10).
Arrow direction). The shift cam 14 has a shape that reciprocates once for one rotation, and during shift, a half rotation is detected by the shift sensor 35, and the shift cam 14 stops. 76 is provided on the shift cam 14,
It is an operation piece that operates the shift sensor 35 every half rotation.

Next, the paper alignment mechanism shown in FIGS. 11 and 12 will be described.

The jogger fences 9 and 9 are driven by a jogger motor 26 via a jogger belt 49 and slide (moving in a black arrow direction or a white arrow direction). As a result, the recording sheets are horizontally aligned.

The return roller 5 is constructed so as to make a pendulum motion via the arm 77 when the return solenoid 30 is turned on and off.
As shown in FIG. 12, the recording paper is vertically aligned by abutting against the trailing edge fence 19.

When the staple mode is selected, the jogger fences 9 and 9 move from the home position and stand by at a position 7 mm on one side of the recording paper width. When the recording paper is sent to the lower conveyance path and the trailing end of the recording paper passes through the paper ejection sensor 37, the jogger fences 9, 9 jog inward by 5 mm. Further, after the passage, the return solenoid 30 is turned on after a predetermined pulse.

For a predetermined time, the return solenoid 30 is turned on, the vertical alignment is completed by the jogger fences 9 and 9, and it is detected that the return solenoid 30 is turned off, the jogger fences 9 and 9 are moved by 2 mm and temporarily stopped. , Horizontal alignment is completed. The jogger fences 9 and 9 then return by 7 mm and wait for the next recording sheet to be discharged onto the staple tray 53. This operation is repeated until the final page. On the final page, jogging of 7 mm is performed again, and the bundle of paper is pressed to prepare for the stapling operation.

Next, the stapler moving mechanism shown in FIG. 13 will be described. Staple mode is selected by the main unit,
When this mode is started, the stapler 11 is moved by the stapler moving motor 27 via the stapler moving belt 50 to an appropriate position according to the size of the recording paper and the number of bound sheets. It waits on the spot during paper alignment, and when the paper alignment on the final page is completed, the stapling operation is performed. Reference numeral 41 is a stapler home position sensor.

Next, the discharge belt mechanism shown in FIGS. 14, 15 and 16 will be described. The ejection belt 10 is driven by the ejection motor 25. The release belt 10 has a release claw 17
The discharge claw 17 has a home position detected by a discharge claw home position sensor 40 shown in FIG. The discharge belt 10 is driven to move the paper stack P.
Is sent to the discharge roller 3 and discharged to the tray 12.
The operation of this discharge belt mechanism will be described. When stapling is completed, the ejection belt 10 is driven, the sheet bundle P is sent to the ejection roller 3, and is ejected to the tray 12. This time,
The discharging belt 10 first starts to lift the sheet bundle in the low speed mode of the double control mode, and then becomes the high speed mode, temporarily stops near the highest position, and then returns to the home position in the low speed mode. Further, the discharge roller 3 starts being driven by the discharge motor 22 at the same time when the discharge belt 10 is started, and stops when the sheet bundle is completely discharged.

As shown in FIG. 16, the discharge motor 2
5, the discharging belt 10, the jogger motor 26, the jogger belt 49, and the stapler moving motor 27.
A stapler moving belt 50 is drivingly connected to each. Further, as shown in FIG. 17, a main conveyor belt 45, an upper conveyor belt 46, and a lower conveyor belt 47 are stretched around the side surface of the apparatus.

FIG. 18 is a block diagram of the overall control.
The U 60 is electrically connected to a copying machine (not shown) by an interface 61 made of an optical fiber, and outputs a command to the transport motor 21, the discharge motor 22, the vertical motor 23, the shift motor 24, the branch solenoid 29, the return solenoid 30, and the like. It is like this. Further, a command is output to the ejection motor 25, the jogger motor 26, the stapler moving motor 27, the staple motor 63, etc. through the I / O 62, and a signal is input from the sensor / switch group 64.

Next, the contents of the control program of the CPU 60 will be described. First, the control operation of the tray home set will be described with reference to FIG. In this flow, at the start of copying, the job counter value for moving the paper discharge tray 12 to the home position is set (the paper surface lever 13 is set to the position shown by the dotted line in FIG. 5). In S1, the start flag (STA
It is checked whether RTF) is set to "1". The start flag (STARTF) is set to "1" by another subroutine (not shown) when a copy start (motor on) signal is transmitted from the copying machine. S
In No. 2, it is checked whether the paper surface SN2 (paper surface sensor 33) is on. Go to S3 with SN2 on (Y in S2). In S3, it is checked whether the lower limit SN (lower limit sensor 34) is on. Lower limit SN on (S3
Then go to S5 with Y). In S4, the tray job counter (TRYJC1) is set to "3". Further, the tray height change flag (TRYHCF) is set to "1". TRYJC1 is a job counter that controls the paper discharge tray 12 in the shift mode. 21 to 25 show tray control in the shift mode. In step S5, a signal is transmitted to the copying machine to notify that the number of copies discharged to the paper discharge tray 12 exceeds the allowable number of paper discharge tray 12. In S6, the tray job counter (TRYJC1) is set to "1". In addition, the tray height change flag (TRY
HCF) is set to "1".

Next, the tray down control operation during copying will be described with reference to FIG. FIG. 20 is a subroutine for checking the states of the paper surface SN1 (paper surface sensor 32) and the paper surface SN2 (paper surface sensor 33) during copying so that the height of the paper ejection tray 12 is always kept the same. Is. In S21, it is checked whether copying is in progress. In S22, tray job counters 1 and 2 (TRY
The value set in JC1, 2) is checked.
If the set value is "0", go to "Y" (checking whether the paper discharge tray 12 has moved).
In S23, it is checked whether the shift mode is set. In the shift mode (Y in S23), go to S4. In S24, it is checked whether the paper surface SN2 is turned on.
Go to S5 with SN2 on (Y in S24). Paper SN
If 2 is off (N in S24), the process goes to S29 to clear the timer (TIM1CU) to "0". S25
Then, it is checked whether the value of the timer (TIM1CU) has become larger than 10. Timer (TIM1CU)
Is incremented by another subroutine not shown. In S26, it is checked whether the lower limit SN is on. When the lower limit SN is ON (Y in S26), the process goes to S28, and in S28, a signal for notifying the copying machine that the number of copies discharged to the discharge tray 12 exceeds the allowable number of discharge tray 12. Are being sent. S27
Then, the tray job counter (TRYJC1) is set to "3".
Is set. TRYJC1 is a job counter that controls the tray in the shift mode. In S30, it is checked whether the tray height change flag (TRYHCF) is set to "1". The tray height change flag (TRYHCF) is set to "1" at S4 in FIG. By operating this flag, the heights of the sheet discharge trays 12 for the first copy and the second copy of the sheet bundle are changed. In S31, it is checked whether the sheet post-processing device is discharging the sheet from the staple tray. If not discharging, go to "N". In S32, it is checked whether the paper surface SN1 is off. SN1 is off (S
At 32, go to S33 with Y). When the paper surface SN1 is on (N in S32), the process goes to S35 and the timer (TIM1C
U) is cleared to "0". In S33, it is checked whether the value of the timer (TIM1CU) has become larger than 10. The timer (TIM1CU) is incremented by another subroutine not shown. S34
Then, it is checked whether the lower limit SN is on.
If the lower limit SN is on (Y in S34), go to S37, S37
Then, a signal is transmitted to the copying machine to inform that the number of copies discharged to the paper discharge tray 12 exceeds the allowable number of paper discharge tray 12. In S36, the tray job counter (TRYJC1) is set to "3". TRYJC1 is the paper ejection tray 1 in the shift mode
It is a counter that controls 2.

Next, the shift mode tray control operation will be described with reference to FIGS. In this flow, the discharge tray 12 is controlled in the shift mode. TRYJC1 is a job counter for controlling the discharge tray 12 in the shift mode. TRYJC1
Depending on the data value set to TRYJ11, TRY
Jump to J12 etc. For example, when the data value set in TRYJC1 is “1”, TRYJ1 in FIG.
1 is executed.

The contents will be described below. First, FIG.
In TRYJ10 shown in (1), if the data value set in TRYJC1 is "0", the process returns. Next, FIG.
In TRYJ11 shown in FIG. 3, in S41, the vertical motor 23 is turned on to raise the paper discharge tray 12. S
At 42, the tray job counter (TRYJC1) is set to "2". In addition, the tray timer (TRY
TIM) is cleared to "0". The tray timer (TRYTIM) is counted up by another subroutine (not shown). Next, TRYJ shown in FIG.
In S12, it is checked in S51 whether the paper surface SN2 is turned on. SN2 on paper (Y in S51)
Then go to S52. When the paper surface SN2 is off (N in S51), the process goes to S53 to check whether the tray timer (TRYTIM) is larger than 250. When the tray timer (TRYTIM) becomes larger than 250, the process goes to S54 and the jam signal is transmitted to the copying machine. In S52, the vertical motor 23 is turned off. Further, the tray job counter (TRYJC1) is set to "3". Next, in TRYJ13 shown in FIG. 25, in S61, the up-down motor 23 is turned on and the discharge tray 12 is lowered. In S62, the tray job counter (TRYJC1) is set to "4". Further, the tray timer (TRYTIM) is cleared to "0". Next, in TRYJ14 shown in FIG. 26, S
At 71, it is checked whether the paper surface SN2 is off. With SN2 off (Y in S71), go to S72. If the sheet SN2 is on (N in S71), the process proceeds to S74 to check whether the tray timer (TRYTIM) is greater than 100. Tray timer (TR
If YTIM) is greater than 100, the process proceeds to S75, and a jam signal is transmitted to the copying machine. In S72, the vertical motor 23 is turned off. Also, the tray job counter (TRYJC1) is set to "0". In S73, the start flag (STARTF) is reset to "0".

Next, the staple mode tray control operation will be described with reference to FIGS. In this flow, the discharge tray 12 is controlled in the staple mode. TRYJC2 is the paper ejection tray 1 in the shift mode
This is a job counter for controlling the number 2. TRYJ
Depending on the data value set in C2, TRYJ21, T
Jump to RYJ22 etc. For example, TRYJC2
When the data value set in is 1, the TR of FIG.
YJ21 is executed.

The contents will be described below. First, FIG.
In TRYJ20 shown in (1), if the data value set in TRYJC2 is "0", the process returns. Next, FIG.
In TRYJ21 shown in FIG. 9, in S81, the vertical motor 23 is turned on to raise the paper discharge tray 12. S
At 82, the tray job counter (TRYJC2) is set to "2". In addition, the tray timer (TRY
TIM) is cleared to "0". The tray timer (TRYTIM) is counted up by another subroutine (not shown). Next, TRYJ shown in FIG.
In S22, in S91, it is checked whether the paper surface SN1 is off. SN1 off (Y in S91)
Then go to S92. When the paper surface SN1 is on (N in S91), the process goes to S93 to check whether the tray timer (TRYTIM) is larger than 250. When the tray timer (TRYTIM) becomes larger than 250, the process goes to S94 to send a jam signal to the copying machine. In S92, the vertical motor 23 is turned off. Also, the tray job counter (TRYJC2) is set to "3". Next, in TRYJ23 shown in FIG. 31, in S101, the up-down motor 23 is turned on to lower the paper discharge tray 12. In S102, the tray job counter (TRYJC2) is set to "4". Further, the tray timer (TRYTIM) is cleared to "0". Next, in TRYJ24 shown in FIG. 32, in S111, it is checked whether the paper surface SN1 is turned on. On paper SN1 (Y in S111)
Then, go to S112. If SN1 is off on the page (S11
1 to N), go to S113, and set the tray timer (TRYTI
I am checking if M) is greater than 100. When the tray timer (TRYTIM) becomes larger than 100, the process goes to S114, and the jam signal is transmitted to the copying machine. In S112, the vertical motor 23 is turned off. Also, tray job counter (TRYJC2)
Is set to "0".

Next, the paper discharge control operation will be described with reference to FIGS. This flow shows the control contents of the discharge roller 3 for discharging the bundle of sheets to the discharge tray 12 in the staple mode. EXITJC is a job counter that controls the discharge roller 3. EXITJ
Depending on the data value set in C, EXIT1, XI
Jump to T2 etc. For example, when the data value set in EXITJC is “1”, EXIT1 in FIG.
Is executed. The contents will be described below. First, FIG.
In EXIT0 shown in FIG. 4, if the data value set in EXITJC is "0", the process returns. Next, FIG.
In EXIT1 shown in FIG. 5, in S121, the discharge motor 22 driving the discharge roller 3 is turned on. Further, "2" is set in the paper discharge job counter (EXITJC). Also, the paper discharge timer (EXITTM) is set to clear "0". Note that the paper discharge timer (EXIT
The count up of M) is performed by another subroutine not shown. Next, in EXIT2 shown in FIG. 36, S
At 131, it is checked whether the discharge SN (discharge sensor 38) is on. When the discharge SN is on (Y in S131), the process proceeds to S132. If the discharge SN is off (S1
31), go to S133, and discharge timer (EXITT)
Checking whether M) has become larger than 200. When the paper discharge timer (EXITTM) is greater than 200, the process goes to S134 to send a jam signal to the copying machine. In S132, the discharge job counter (EX
ITJC) is set to "3". Also, the paper discharge timer (EXITTM) is set to clear "0". next,
In EXIT3 shown in FIG. 37, in S141, it is checked whether the discharge SN is off. When the discharge SN is off (Y in S141), the process proceeds to S142. If the discharge SN is on (N in S141), the process proceeds to S143, and it is checked whether the discharge timer (EXITTM) is greater than 250. Discharge timer (EXIT ™) is 250
When it becomes larger than the above, the process goes to S144, and the jam signal is transmitted to the copying machine. In step S142, the discharge job counter (EXITJC) is set to "4". Also, the paper discharge timer (EXITTM) is set to clear "0". Next, in EXIT4 shown in FIG. 38, S15
In No. 1, it is checked whether the paper discharge timer (EXITTM) has become larger than 50. Ejection timer (EXIT
When TM) becomes larger than 50, the process goes to S152, and the tray height change flag (TRYHCF) is reset to "0". In addition, the discharge job counter (EXI
TJC) is set to "5". Then, the tray height change flag (TR
YHCF) is reset to “0” (S
30), go to S31. When the software after S31 is executed, "3" is set in the job counter (TRYJC2) that controls the height of the discharge tray 12 (S3).
6). When "3" is set in the job counter (TRYJC2), the staple mode tray control subroutine of FIG. 27 is executed, and the height of the discharge tray 12 is lowered [Tray height change flag (TRYHCF) is set " 1 ", the height of the sheet discharge tray 12 is executed by the shift mode tray control subroutine of FIG.
Is set to a position higher than when the stapling mode tray control subroutine is executed.]. By operating this flag, the heights of the sheet discharge trays 12 for the first copy and the second copy of the sheet bundle are changed. Next, in EXIT5 shown in FIG. 39, in S161, the paper discharge timer (EXITTM) is set to 2
I am checking if it has become larger than 00. If the paper discharge timer (EXITTM) is greater than 200, the process proceeds to S162, the discharge motor 22 driving the discharge roller 3 is turned off, and the paper discharge job counter (EXITJT).
"0" is set in C). This subroutine is a subroutine for achieving the invention described in claims 1 and 2.

In order to achieve the invention described in claim 3,
The contents of EXIT5 in FIG. 39 may be changed to the contents of EXIT5 in FIG.

Next, in EXIT5 shown in FIG. 40,
In S171, it is checked whether the paper discharge timer (EXIT ™) has become larger than 200. If the paper discharge timer (EXITTM) is greater than 200, S
172, the discharge motor 22 driving the discharge roller 3 is turned off, and the discharge job counter (EXITJC)
Is set to "0". Further, "1" is set in the tray job counter (TRYJC1). Also,
The tray height change flag (TRYHCF) is set to "1". The tray height change flag (TRYHCF) in FIG. 38 (EXIT4) is reset to "0".
Then, the tray job counter (TRYJC1) is set to "1" at the timing when the discharge tray 12 is slightly lowered to the state of FIG. 42B, and the tray height change flag (TRYHCF) is set. 42) is set to "1" so that the state of FIG. 42 (c) is obtained.

In the above-described embodiment, the stapler 11 for receiving the sheets discharged from the image forming apparatus on the upstream side and binding the plurality of sheets, and the vertical movement for stacking the bound sheet bundle In a sheet post-processing apparatus having a sheet discharge tray 12 capable of discharging, when stacking the bound sheet of sheets on the sheet discharge tray 12, the stacking surface height of the sheet discharge tray 12 for the first copy and the second and subsequent copies. Is provided, or the stacking surface height is made higher than the others only when the first set of sheet bundle is discharged. Therefore, as shown in (a) of FIG. 41, the paper ejection tray 1 is ejected only when the first copy of the paper bundle is ejected.
When 2 is held upward, the landing angle θ becomes small and the sliding resistance between the leading edge of the sheet bundle and the sheet ejection tray 12 becomes small, so that the leading edge of the sheet bundle slides smoothly on the sheet ejection tray 12. Therefore, as shown in FIG. 7B, the sheet bundle does not bend and slips down to the back fence 15 accurately. Next, as shown in FIG. 3C, when the paper discharge tray 12 is lowered at the timing when the first set of sheet bundles have finished passing through the discharge rollers 3, the stacking surfaces of the second and subsequent sets are lowered, Since the sliding frictional resistance becomes small due to the contact between the sheets, the bundle of sheets is discharged smoothly, completely slides down to the back fence 15, and is stacked on the discharge tray 12 in an orderly manner as a whole. As described above, a predetermined number of sheets in the staple mode can be reliably stacked on the sheet discharge tray 12, and a highly reliable sheet post-processing apparatus can be provided.

In the above embodiment, the stapler 11 for receiving the sheets discharged from the image forming apparatus on the upstream side and binding the plurality of sheets, and the vertically movable sheet discharge tray 12 for stacking the bound sheet bundle are provided. In the sheet post-processing apparatus including the above, when the bound sheet bundle is discharged onto the sheet discharge tray 12, the CPU 60 is provided for temporarily raising the stacking surface of the sheet discharge tray 12 each time the sheet bundle is discharged. . Therefore, as shown in (a) of FIG. 42, when the sheet discharge tray 12 is always kept in a high position when discharging the sheet bundle, the stacking surface becomes higher, so that the sheet bundle is less drooped and the landing angle θ. Also becomes smaller, and when the leading edge of the sheet bundle slips, it is less likely to flip over. The height of the stacking surface is set to a position where it is almost in contact with the shifting roller 7. Next, as shown in FIG. 7B, the paper output tray 1
2, the space between the moving roller 7 and the loading surface is 10 to 15 m
Lower it to the level of m. Therefore, the discharged sheet bundle can smoothly slide down on the back fence 15. After that, as shown in FIG. 7C, the paper discharge tray 12 is again raised to a position where the stacking surface is almost in contact with the shift roller 7, and the next paper stack is discharged as described above.

As described above, the stacking amount of the sheet bundle can be secured by repeating the vertical movement of the sheet discharge tray 12. As described above, the stacking surface of the paper discharge tray 12 is temporarily raised every time the paper stack is discharged, so that a predetermined number of paper stacks in the staple mode can be reliably stacked on the paper discharge tray 12. Therefore, it is possible to provide a paper post-processing device having excellent reliability. In the above embodiment, CP
U60 is a paper surface detection lever 13 and two paper surface sensors 32 and 33 for detecting the swing displacement of the paper surface detection lever 13.
Since it is configured by the vertical motor 23 that moves the discharge tray 12 up and down by the sensor output, the mechanism can be simplified and the cost can be reduced by simplifying the control means.

[0049]

According to the inventions of claims 1 and 2,
Since the stacking surface height of the paper discharge tray is set higher than the others only when the first set of paper stacks is discharged, a predetermined number of paper stacks in the staple mode can be reliably stacked on the paper discharge tray. It is possible to provide a paper post-processing device having excellent reliability. According to the third aspect of the present invention, the stacking surface of the paper discharge tray is temporarily raised every time the paper stack is discharged. Therefore, a predetermined number of paper stacks in the staple mode are reliably placed on the paper discharge tray. A sheet post-processing device that can be stacked and has excellent reliability can be provided. According to the fourth aspect of the present invention, by simplifying the control means, the mechanism can be simplified and the cost can be reduced.

[Brief description of drawings]

FIG. 1 is a front view of a sheet post-processing apparatus according to an exemplary embodiment of the present invention.

FIG. 2 is a front view of a branch pawl drive mechanism.

FIG. 3 is a front view of a branch pawl drive mechanism.

FIG. 4 is a perspective view of a paper discharge tray vertical drive mechanism.

FIG. 5 is a front view of a main portion of a paper discharge tray vertical drive mechanism.

FIG. 6 is a front view of a main part of a paper discharge tray vertical drive mechanism.

FIG. 7 is a perspective view of a paper discharge tray shift mechanism.

FIG. 8 is a perspective view of a main part of a paper discharge tray shift mechanism.

FIG. 9 is a front view of a main part of a paper discharge tray shift mechanism.

FIG. 10 is a front view of a main part of a paper discharge tray shift mechanism.

FIG. 11 is a perspective view of a paper alignment mechanism.

FIG. 12 is a front view of the paper alignment mechanism.

FIG. 13 is a perspective view of a stapler moving mechanism.

FIG. 14 is a perspective view of a discharge belt drive mechanism.

FIG. 15 is a perspective view of a main part of a discharge belt drive mechanism.

FIG. 16 is a perspective view of a drive mechanism of each unit.

FIG. 17 is a perspective view of a drive mechanism of each unit.

FIG. 18 is a control block diagram of the sheet post-processing apparatus according to the embodiment of the present invention.

FIG. 19 is a control flowchart of the tray home set.

FIG. 20 is a control flowchart of tray down during copying.

FIG. 21 is a flowchart of shift mode tray control.

FIG. 22 is a flowchart of a subroutine of shift mode tray control.

FIG. 23 is a flowchart of a shift mode tray control subroutine.

FIG. 24 is a flowchart of a subroutine of shift mode tray control.

FIG. 25 is a flowchart of a subroutine of shift mode tray control.

FIG. 26 is a flowchart of a subroutine of shift mode tray control.

FIG. 27 is a flowchart of staple mode tray control.

FIG. 28 is a flowchart of a staple mode tray control subroutine.

FIG. 29 is a flowchart of a staple mode tray control subroutine.

FIG. 30 is a flowchart of a staple mode tray control subroutine.

FIG. 31 is a flowchart of a staple mode tray control subroutine.

FIG. 32 is a flowchart of a staple mode tray control subroutine.

FIG. 33 is a flowchart of paper discharge control.

FIG. 34 is a flowchart of a paper discharge control subroutine.

FIG. 35 is a flowchart of a discharge control subroutine.

FIG. 36 is a flowchart of a paper discharge control subroutine.

FIG. 37 is a flowchart of a discharge control subroutine.

FIG. 38 is a flowchart of a discharge control subroutine.

FIG. 39 is a flowchart of a paper discharge control subroutine.

FIG. 40 is a flowchart of a paper discharge control subroutine.

FIG. 41 is a schematic diagram showing the first control content of the present invention.

FIG. 42 is a schematic diagram showing the second control content of the present invention.

FIG. 43 is a schematic diagram for explaining the first problem of the conventional example.

FIG. 44 is a schematic diagram for explaining a second problem of the conventional example.

[Explanation of symbols]

 11 stapler (binding means) 12 paper ejection tray 13 paper surface detection lever 23 vertical motors 32, 33 paper surface sensor 60 CPU

Claims (4)

[Claims] 1. A sheet post-processing including a binding unit that receives sheets discharged from an upstream image forming apparatus and binds a plurality of sheets, and a vertically movable discharge tray that stacks the bound sheet bundle. In the apparatus, the sheet post-processing is provided with a control unit that changes the stacking surface height of the discharge tray between the first copy and the second and subsequent copies when discharging the bound sheet bundle onto the discharge tray. apparatus. 2. The sheet post-processing apparatus according to claim 1, wherein the stacking surface height is made higher than the others only when the first set of sheet bundles is discharged. 3. A sheet post-processing including a binding unit that receives sheets discharged from an image forming apparatus on the upstream side and binds a plurality of sheets, and a vertically movable discharge tray that stacks the bound sheet bundle. A sheet post-processing apparatus, comprising: a control unit that temporarily raises the stacking surface of the sheet discharge tray every time the sheet bundle is discharged when the bound sheet bundle is discharged onto the sheet discharge tray. . 4. The control means according to claim 1, wherein the control means is a paper surface detection lever, two sensors for detecting the swing displacement of the paper surface detection lever, and a vertical movement mechanism for vertically moving the paper discharge tray by sensor output. A sheet post-processing device comprising a motor.