JPH0867400A - Sheet after-process device - Google Patents

Abstract

PURPOSE: To efficiently gather, bind, and discharge at high speed sheets in every number of copies by returning a movable registering plate once to the home position after the binding process, when the number of sheets in a sheet bundle on a first tray is more than the scheduled number of sheets. CONSTITUTION: Sheets P are once received on a first tray, and after a registered bundle of sheets is bound by a stapling means ST1, it is discharged to a second tray. The sheets P received on the first tray are registered in the feed direction. In this case, one side end face of the sheets P is regulated with a reference guide face 426A, and the other side end face is pressed by means of a movable registering plate 4274 so as to be registered. The home position of the movable registering plate is detected by a sensor. Further, according to the number of sheets P, a driving means M4 is controlled to be variable. As a result of this, when the number of sheets in the bundle of sheets on the first tray is more than the scheduled number of sheets, after the binding process, the movable registering plate 4274 is once returned to the home position.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet post-processing apparatus for automatically binding and discharging recording sheets (sheets) on which images are recorded by an image forming apparatus, and particularly to a high-speed image forming apparatus. The present invention relates to a sheet post-processing device that can handle the above.

[0002]

2. Description of the Related Art A sheet post-processing device called a finisher is used as a device for collating a plurality of image-recorded sheets discharged from an image forming apparatus for each number of copies and binding them by a stapler.

The finisher has a function connected to the image forming apparatus main body and is driven in response to the sequence operation of the copying process.

Therefore, for an image forming apparatus capable of high-speed processing of the copy process, a finisher capable of high-speed processing capable of following the speed and performing its function is required.

Regarding the finisher capable of such high speed processing, Japanese Patent Laid-Open Nos. 60-142359 and 60-158463 have already been disclosed.
No. 62-239169, and JP-A Nos. 62-288002 and 63-267.
The proposals disclosed in Japanese Patent Publication No. 667, Japanese Patent Laid-Open No. 2-276691, and Japanese Patent Publication No. 5-41991 are disclosed.

In the sheet post-processing apparatus, the image-recorded sheets carried out from the main body of the image forming apparatus are sequentially stacked while being aligned in the intermediate stacker to store a set of sheet bundles, and then the stapler or the like. The sheet post-processing is performed, and the bound sheet bundle is discharged to a sheet discharge tray via a sheet discharge roller by a discharge belt provided at the bottom of the intermediate stacker.

When the sheets are accommodated in the stacker and aligned for performing post-processing such as stapling, the stiffness of the sheets changes depending on the number of sheets. That is, when the number of sheets is less than or equal to the number of sheets, the sheet surface is easily bent due to lateral pressure at the time of alignment, and when the number of sheets is many, the bending of the sheet surface is small.

FIG. 9 (A) is a sectional view of the alignment means showing the alignment state when the number of sheets is small. In the figure, 1 is a fixed intermediate stacker, and 2 is a movable aligning plate that presses the side edges of the sheets P stacked on the intermediate stacker 1 to align the sheets. Each time the sheet P is stored on the intermediate stacker 1, the movable aligning plate 2 is moved from the standby reference position A1 by the driving of a stepping motor (not shown), passes through the sheet width position A2, and is slightly smaller than the sheet width position. Reaches the alignment position A3 set to, and then reverses and returns to the standby reference position A
Reciprocate back to 1. If the number of sheets P is small, the surface of the sheet P is temporarily curved at the alignment position A3 as shown in the figure, but this does not affect the driving of the movable alignment plate 2. Note that HP indicates the home position position of the movable aligning plate 2, and is stopped at this HP position before the sheet aligning drive is started.

FIG. 9B is a sectional view of the aligning means showing the aligned state when the number of sheets is large. When the number of sheets P accommodated in the intermediate stacker 1 exceeds a certain number, the movable aligning plate 2 reaches the aligning position A3 even if the movable aligning plate 2 tries to drive the aligning position A3 due to the strength of the sheet P. Without doing so, the drive source stepping motor goes out of step, the movable aligning plate 2 stops at the sheet width position A2, and alignment is performed at this aligning position B2. After the alignment, the movable aligning plate 2 is reversed and returned, but because of the stepping motor step-out from the standby position B1, it comes to a position retracted from the first standby reference position A1. The subsequent alignment of the sheets P is continuously performed with the same stroke from the standby position B1. After the alignment of the sheet bundle is completed, sheet post-processing such as stapling is performed. However, after the alignment of one sheet bundle is completed, the movable aligning plate 2 is returned to the home position HP at the time of aligning the sheet of the next portion. The misalignment between the standby position B1 and the alignment position B2 is corrected.

The sheet post-processing device disclosed in Japanese Patent Application Laid-Open No. 62-288002 is one in which the aligning means is set at three positions with respect to one sheet bundle.

The sheet post-processing apparatus disclosed in Japanese Patent Laid-Open No. 62-288003 returns the aligning means to the home position for each one sheet bundle on the tray. If the sheet is returned to the home position HP every time one sheet is stored in consideration of the stepping out of the stepping motor, the movable aligning plate will not be in time when aligning the sheets discharged by the high speed copying machine. Further, the sheet post-processing apparatus is provided with an upper and lower two-stage intermediate stacker, and the two-stage intermediate stacker
Even when each sheet bundle is alternately accommodated and aligned to perform post-processing, in the case of a slightly large number of sheet bundles, the stepping motor loses step, so the operation of returning the movable aligning plate 2 to the home position is performed. Since a predetermined number of sheets P are stored in the two-stage intermediate stacker so that the succeeding sheets P are immediately accommodated in the first-stage intermediate stacker in order to insert each sheet or when one copy is completed, the second-stage intermediate stacker Since the movable aligning plate 2 is not returned from the home position HP to the standby position, there is a problem that the operation time is not in time and the sheet post-processing efficiency is reduced.

[0012]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems and improve the results, and as a result, to provide a large number of sheets which can be sufficiently applied to an image forming apparatus for high speed printing of about 90 sheets per minute. A sheet post-processing device (finisher) that can align and perform post-processing such as stapling and smoothly discharge a sheet bundle
Is to provide.

[0013]

SUMMARY OF THE INVENTION The above-mentioned object is to feed a sheet introduced from an image forming apparatus and feed the sheet, and stack the sheet fed from the sheet feeding unit at a predetermined position to temporarily A first tray to be stored, an aligning unit that aligns the sheets on the first tray in a direction orthogonal to the sheet feeding direction, and a staple that binds the bundle of sheets stacked and aligned on the first tray. In the sheet post-processing apparatus, the aligning means includes a sheet feeding means, a discharging means for transporting and discharging the bound sheet bundle, and a second tray for storing the sheet bundle discharged by the discharging means. A reference guide surface portion that is provided in a direction orthogonal to the feeding direction and regulates one side end surface of the sheet, and a movable alignment that is arranged so as to face the reference guide surface portion and that presses the other side end surface of the sheet so as to be contactable and separable. A plate, a drive unit that reciprocates the movable alignment plate in a direction orthogonal to the sheet feeding direction, a detection unit that detects a home position of the movable alignment plate, and a drive unit that operates according to the number of sheets in the sheet bundle. When the number of sheets of the sheet bundle on the first tray is larger than a preset number, the control means and the drive means move the sheets after the binding processing by the stapling means. This is achieved by a sheet post-processing device characterized by controlling the alignment plate to return to the home position once.

[0014]

Embodiments of the sheet post-processing apparatus of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 is an overall configuration diagram of a copying machine equipped with a sheet post-processing device. 100 is a copying machine main body, 200 is a paper feeding unit (PFU device), and 300 is a circulation type automatic document feeder (RDH device). ), 400 is a sheet post-processing device (finisher, hereinafter also referred to as FNS device).

The copying machine main body 100 includes a scanning exposure unit 110, an image forming unit 120, a paper feeding unit 130, a conveying unit 140, a fixing unit 150, a paper discharge switching unit 160, a plurality of paper feeding cassettes 170, and a double-sided recording sheet reprocessing unit. It is composed of a sheet feeding device (ADU device) 180.

In the figure, the alternate long and short dash line indicates the conveyance path of the sheet P. The sheet P stored in the paper feed cassette 170 or the paper feed unit (PFU device) 200 at the bottom of the copying machine main body 100 is
After the image is formed by the image forming unit 120, the conveying unit 140
Then, the main route stored in the FNS device 400 via the fixing unit 150 and the paper discharge switching unit 160, and the sheet P branched from the paper discharge switching unit 160 are temporarily stocked in the ADU device 180 and then re-fed. And a circulation route to the paper feeding unit 130 of the copying machine main body 100.

The document D stacked on the document table of the RDH device 300 is fed by the copy button operation on the operation panel of the copying machine main body 100, and is fed by the conveyor belt 302 via the paper feeding unit 301. It is transported onto the platen glass 111 and installed at the exposure position.

The original document D is read by receiving the exposure scan of the original image by the operation of the operation exposure unit 110, and after the reading is completed, the conveyance belt 302 is rotated again to be fed, and is fed through the reversing paper discharge path 303. It is accommodated in the lowermost layer of the original stack on the original placing table.

Although the circulation of the original document D has been described above, the RDH device 300 is not limited to the automatic document feeder (AD).
F is also provided with the function of F). In that case, the document D whose image has been read goes straight and is ejected through the ejection rollers to the ejection tray 30.
4 Discharge and stack on top.

The copy image of the original D obtained by the exposure scanning is subjected to the image processing process of the copying machine main body 100, and the sheet P fed from the paper feeding cassette 170 or the PFU device 200.
Recorded in.

The sheet P on which the image is recorded is the above-mentioned ADU.
The sheet is once fed to the apparatus 180, turned upside down, and discharged from the sheet discharge switching unit 160 in a posture with the image surface facing downward.
The paper is fed to the S device 400.

FIG. 2 is a sectional view showing the structure of the FNS device 400. The FNS device 400 is installed by adjusting the position and height so that the receiving roller 401 of the sheet P is aligned with the sheet discharge port of the copying machine main body 100, and is controlled so as to be driven according to the operation of the copying machine main body 100. Connected to the system.

The conveying path of the sheet P connected to the rear side of the receiving roller 401 is an upper offset conveying path 410 (first
A conveyance path), a second conveyance path 420 in the middle stage, and a third conveyance path 430 in the lower stage, and the sheet P is fed to one of the conveyance paths by selecting the angle occupied by the switching gates G1 and G2. It will be sent. U1 is the first
A first unit forming a conveyance path, U2 is a second unit forming a second conveyance path, and U3 is a third unit forming a third conveyance path.
It is a unit.

The second transport path 420 and the third transport path 430 described above.
Is equipped with guide belts 422 and 432 at each end on the downstream side of the conveyance, and feeds the trailing end of the sheet P to the stapler section. Further, at positions facing the guide belts 422 and 432, discharge belts (timing belts) 425 and 435 provided with discharge claws 424 and 434, respectively, and a first position at a position sandwiching these discharge belts 425 and 435. The stacker 426 and the second stacker 436 are installed with a predetermined inclination angle. Of the three rollers wound around the guide belts 422 and 432, the lowermost roller is the impellers 423 and 433, so that the sheet P
When the switch backs, the sliding contact action of the impellers 423 and 433 may surely abut the stoppers 441 and 451 described later.

Further, a first stapler ST1 and a second stapler ST2 are arranged at positions facing the respective lower end portions of the first stacker 426 and the second stacker 436.

On the downstream side of the sheet conveyance of the first stacker 426, near the sheet ejection section of the FNS device 400, there is provided a first sheet ejection means 460 consisting of a pair of upper and lower sheet ejection rollers. Similarly, a second sheet discharging unit 470 is provided on the downstream side of the second stacker 436.

Further, on the right side of the FNS device 400, a paper discharge tray elevating means 480 is arranged. The paper output tray elevating means 480 is provided with a pair of support members 482 before and after vertically moving by engaging a plurality of guide rollers 481.
The first discharge tray T1 and the second discharge tray T2 are respectively sandwiched by the support member 482 and vertically moved separately.

The pair of supporting members 482 is a lifting wire 484 stretched between individual dedicated motors M1 and M2 and a pulley 483.
The first paper discharge tray T1 and the second paper discharge tray T2 are individually moved in parallel in the vertical direction by rotation of the motors M1 and M2.

The control circuit built in the copying machine main body 100 is shown in FIG.
The basic circuit as shown in FIG. 3 is formed, and before the copy operation is started, the paper discharge mode (staple mode or non-sort mode) is selected, and the number of originals and the number of copies are set.

When the non-sort mode which does not require binding is set, the switching gates G1 and G2 are held in the initial state, the sheet P moves straight, and the receiving roller 40 is moved.
1, the intermediate roller 402, the conveyance belt 403, and the discharge roller 404, and a first conveyance path (offset conveyance path) 410 is discharged to the outside of the machine, and the sheet is placed and stored on the upper first discharge tray T1.

When the offset mode is selected as the sheet discharge mode, the switching gates G1 and G2 are held in the initial state, the sheet P is fed upward, and the sheet P is fed to the first conveying path 410. Conveyor belt 403 and discharge roller 40
It is ejected onto the first ejection tray T1 via 4. A pair of the discharge rollers 40 including a driving roller and a driven roller.
Numeral 4 is provided with an offset driving unit capable of reciprocating in the direction perpendicular to the drawing, and shift-driving after detecting the trailing edge passage of the discharged sheet P to make the sheet P zigzag in the left and right direction with respect to the discharged sheets. It is configured so that they can be stacked and sorted easily.

When the binding mode is selected as the paper discharge mode, the switching gate G2 rotates, and the sheet P fed by the receiving roller 401 advances straight and is fed to the second transport path 420. , The guide belt 4 in the second unit U2
The sheet P is temporarily pushed up and placed on the first stacker 426 via the guide belt 422.
And the weight of the sheet P slides down on the first stacker 426 and is guided to the binding portion of the first stapler ST1 (stopper 441 of the sheet passing portion 440).

First sheet P corresponding to the number of originals D
After the last sheet of the sheet is detected by the sensor S1, the switching gate G1 is rotated, and the sheet P of the second copy is fed downward and fed to the third conveyance path 430, and is guided in the same manner as described above. Belt 4
By the action of 32, the push-up mounting is started on the second stacker 436. The transfer unit 450 of the third unit U3
Has the same structure as the sheet passing portion 440 of the second unit U2.

On the other hand, during the feeding of the second set of sheets P,
The sheets P of the first set, which have been stacked, are bound by the operation of the first stapler ST1, and then the first stacker 426 is pushed by the pushing back operation of the delivery lever 442.
It is pushed up against the gravity to a predetermined position and held.

FIG. 4 is a sectional view of the sheet discharging portion. Figure 5
5A is a plan view of the sheet discharging portion, FIG. 5B is a sectional view taken along line AA, and FIG. 5C is a sectional view taken along line BB.

The delivery lever 442 of the sheet delivery unit 440 reciprocates only when the bound sheet bundle is discharged.

The first discharge belt 425 is driven by the motor M3 to rotate the gears Z1 and Z2 and the timing pulley TP1.
Through the TP2 and the timing belt TB1, the first copy of the sheet P that has been bound while starting to rotate in the direction of the arrow and pushing up the rear end surface of the sheet P by the discharge claws 424 and stopping for one round is stopped. The sheet is discharged onto the first sheet discharge tray T1.

During this time, the stacking of the sheets P of the second copy is completed and the switching gate G2 is restored again.
The second set of sheets P is bound by the operation of the second stapler ST2, and the second set of sheets P bound by the protrusion of the stopper 451 and the rotation of the second discharge belt 435 are the same as those described above. 2 The sheet is discharged onto the sheet discharge tray T2.

As described above, according to the FNS device 400 of the present invention, a plurality of sheets P on which images are recorded can be collated and bound in parallel at two places without a particular time difference. The post-treatment of P will be performed quickly.

The motor M3 operates according to the discharge amount of the sheet P, and the first and second sheet discharge trays T1 and T2 are lowered by the number corresponding to the number of processed sheets so that the sheet P can be discharged. .

The above-mentioned first and second staplers S
Both T1 and ST2 are the first and second stackers 426.
And 436 are installed on the front side of the drawing,
When the sheet P is placed vertically long and ejected, the upper left one place can be bound with staples, but if a stapler is additionally installed on the back side of the drawing, it is also possible to bind with two staples. When the paper is ejected horizontally, it is possible to staple the upper left one place with staples.

The matching process of the present invention will be described below with reference to FIGS.
Will be described.

The number of copies to be copied and the set value (N1) of the number of sheets for each part are sent by communication from the main body of the copying machine.

Intermediate stacker 426 of the sheet post-processing device 400
(436) The number of passing sheets P is sequentially counted by the sensor S42 (S43) provided near the entrance (N2).

The sheet P is conveyed onto the intermediate stacker 426 (436), slides down the inclined surface, contacts the stopper 441 (451), and stops.

At this stop position, the movable aligning plate 4274 of the aligning means 427 moves toward the side edge of the sheet P from a position about 20 mm away from the outer side in the width direction of the sheet P, and the sheet P is moved.
Is pressed against the reference surface 426A, and further about 3 m from the width of the sheet P.
m Return to the original position by flipping to the inner position.

Stacker 426 (436) for each sheet P
The movable aligning plate 4274 reciprocates once every time it is conveyed upward to perform the paper aligning operation. Intermediate stacker 426 (43
6) When the succeeding sheet P slides down, the preceding sheet P has its own weight and the succeeding sheet P when the succeeding sheet P slides down.
The sliding contact with the slides the slide to the stopper 441 (451) side.

When the number of sheets P conveyed onto the intermediate stacker 426 (436) is counted by the sensor S42 (S43) and it is detected that the set value N1 is met (N2 = N1), it is finally determined. With respect to the sheet bundle in which the sheets P are stacked, the movable aligning plate 4274 is set to 1 by the paper aligning operation.
After reciprocating movement, the sheet bundle is moved again to the side edge of the sheet bundle and is pressed against the sheet bundle side edge (final alignment operation).

In this sheet bundle pressure contact state, a paper pressing lever 443, which will be described later, rises to press the rear end of the sheet bundle, and the stapling operation is performed.

When the number N2 of sheets is 25 or less, the above-mentioned paper aligning operation for each sheet and the final aligning operation after the final sheet is stopped are performed.

When the number of sheets N2 is 25 or more,
After the paper aligning operation described above is performed and the final sheet P is placed on the sheet bundle on the stacker 426 (436), about 1
After a lapse of seconds, the final alignment operation is performed, and the paper pressing lever 443 is lifted and the stapling operation is performed while the side ends of the sheet bundle are pressed against each other. This is a stacker for many sheets of 25 or more
When stacked on 426 (436), the final paper will stop without contacting the stopper. On the other hand, by leaving a margin of about 1 second after the paper alignment for the final alignment operation, the final sheet P slides down on the preceding sheet P by its own weight and moves toward the stopper 441 (451). Advance and stop. In this way, the final sheet P can surely slide down to the predetermined stop position. This sheet alignment result is particularly large when the sheet is conveyed at high speed. The margin time of about 1 second is not limited to this.
It depends on the sheet conveying speed, the surface friction of the sheet, the weight of the sheet, the inclination angle of the intermediate stacker 426 (436), etc., and the optimum margin time is determined by these setting conditions.

The first transport path 420 provided in the upper second transport path 420
Since the aligning means 427 of the stacker (intermediate stacker) 426 and the aligning means of the second stacker 436 provided on the lower third transport path have the same structure, the upper aligning means 427 will be described below as a representative.

Sheet P discharged onto the first stacker 426
The width direction (direction orthogonal to the transport direction) mounting position is the first
The reference surface (rising surface) 426A of the stacker 426, the drive pulley 4271 and the driven pulley that are rotated by the drive of the motor M4.
It is regulated within the interval between the rising surface 4274A of the movable matching plate 4274 locked by the timing belt 4273 that winds the 4272. The bearing portion 4274B of the movable matching plate 4274 is the second unit U.
The movable aligning plate 4274 is fitted to a guide shaft 4275 installed on the second machine frame, and is supported so as to be capable of reciprocating in a direction orthogonal to the sheet conveying direction. Further, a resin guide 4276 is integrated with the other end of the movable matching plate 4274, and is fitted and movably supported by a guide member 4277 fixed to the unit machine frame.

The bearing portion 4274B side of the movable aligning plate 4274 is locked to the timing belt 4273 and is rotated by the driving rotation of the stepping motor M4.
Moves back and forth with 4273. An optical path shielding plate portion 4274C projects near the bearing portion 4274B, and detects a predetermined home position position of the movable matching plate 4274 by turning on / off the detection optical path of the photo interrupter type home position sensor S14.

FIG. 6A is a schematic plan view for explaining the paper aligning process of a small number of sheets P. The guide belt
The sheet P sent out from the sheet 422 once goes up on the discharge belt 425, then falls on the discharge belt 425 with an inclination and collides with the stopper 441 to stop. Up to now movable matching plate 427
4 is a standby reference position A 20 mm apart from the side edge of the sheet P
Waiting for 1. Next, when the sheet P hits the stopper 441 and stops, the stepping motor M4 drives to move the movable aligning plate 4274 forward by 23 mm in the sheet width direction.
At this alignment position A3, the sheet P is 3 in the sheet width direction.
mm (23 ~ 20mm) compressed, the seat surface is curved,
The right end of the sheet P is pressed against the reference surface 426A of the intermediate stacker 426 to perform paper alignment (paper alignment). Thereafter, the movable aligning plate 4274 or the stepping motor M4 is driven in the reverse direction to return to the return stroke, and the initial standby reference position A1 is restored and the operation is stopped. The succeeding sheet P is fed and paper alignment is performed in the same manner as described above.

FIG. 6B is a schematic plan view showing the alignment process of a large number of sheets P. When the number of sheets P stacked on the intermediate stacker 426 exceeds a certain number, it depends on the size of the sheets P, the weight of the sheets, and the paper quality. If the alignment position A3 (CW23mm) in the case of a single sheet is not reached,
The stepping motor M4, which is the drive source, goes out of step, and the movable matching plate 4274 stops at the sheet width position A2 (CW20m
m), alignment is performed at this alignment position B2. After the paper alignment, the movable alignment plate 4274 reverses and returns (CCW23mm),
It stops at the standby position B1. The standby position B1 is a position retracted by 3 mm from the initial standby reference position A1 because the stepping motor M4 has already been out of step. From the standby position B1, the subsequent paper alignment of the sheet P is continuously performed with the same stroke (CW23 mm, CCW23 mm).

FIG. 7A is a schematic plane view for explaining the operation process of the aligning means 427 after the partial copy consisting of a small number of sheets is completed. After the partial copy is completed, the final sheet P is paper-aligned and stacked on the intermediate stacker 426, and then the stapling operation is performed, and thereafter, the movable alignment plate.
4274 is a small gap (3 mm in the figure) from the sheet width position A2
Are retracted to the separated position A4. In the retracted state of the movable aligning plate 4274, the sheet P is discharged and placed on the first discharge tray T1 outside the machine through the discharge means 460 by the cooperation of the delivery lever 442 and the discharge belt 425. When this sheet bundle is discharged, the movable aligning plate 4274 at the retracted position A4 regulates the inclination of the sheet bundle. When the sheet bundle passes the aligning means 427 and the discharge belt 425, the movable aligning plate 4274 retracts and returns to the standby reference position A1.

FIG. 7B is a schematic plan view for explaining the operation process of the aligning means 427 at the end of the partial copy consisting of many sheets. After the partial copy is completed, the final sheet P is paper-aligned and stacked on the intermediate stacker 426, and after the stapling operation, the movable aligning plate 4274 is retracted to the A4 position as described above. After the sheet bundle is discharged, the movable aligning plate 4274 is once returned to the home position HP and then moved to the standby reference position A1 to enter the standby state. This is because when the multiple sheets are aligned, the stepping motor M4 is out of step as described in FIG. 6B, and therefore the misalignment is corrected by returning to the home position HP.

FIG. 8 is a flow chart showing the operation process of the matching means 427. FIG. 8A shows a sheet post-processing device 40.
The initialization operation of the matching means 427 at the time of starting of 0 is shown, and after the movable matching plate 4274 is positioned at the home position HP by driving the matching motor (stepping motor) M4, the driving is temporarily stopped and stands by.

FIG. 8B shows the operation of driving the alignment motor M4 to position the movable alignment plate 4274 at the standby reference position A1, which is the sheet width position A2 in FIGS. 6A and 6B described above. The movable aligning plate 4274 is stopped at the standby reference position A1 spaced 20 mm away from.

FIG. 8C shows the paper aligning operation, in which the paper aligning operation is repeated by the CW forward moving amount 23 mm and CCW 23 mm backward moving amount of the movable aligning plate 4274 in FIGS. 6A and 6B.

FIG. 8D shows the operation of the movable matching plate 4274 at the end of partial copying. When the number of sheets for one copy is less than a predetermined set number (for example, 11 sheets), every time one sheet of the movable aligning plate 4274 is received, the sheet is aligned from the standby reference position A1 and paper alignment is performed, and the process is completed. If the number of sheets is equal to or larger than the set number (for example, 11 sheets), the above-mentioned FIG.
After performing the initialization shown in (A), the process returns to the standby reference position A1 and ends. Therefore, when a small number of sheets are returned to the home position HP, the productivity decreases by the amount of the reciprocating time. Therefore, the sheet is not returned to the HP, and the stepping motor step out is considered only when aligning a large number of sheets. Restore HP.

The above-mentioned standby reference position A1 is set for a plurality of types of sheets at predetermined intervals corresponding to the sheet width, and is not limited to 20 mm in the embodiment. Similarly, the CW forward movement amount of the movable aligning sheet 4274 23
mm, CCW backward movement amount 23 mm, partial copy retract position (A
4) The present invention is not limited to 3 mm.

Although the sheet post-processing apparatus of this embodiment is shown as being connected to a copying apparatus, it may be used by connecting to an image forming apparatus such as a printer or a facsimile or a light printing machine.

[0066]

According to the present invention, a plurality of thick sheet bundles can be efficiently and smoothly collated and bound for each number of copies. In particular, the sheet post-processing device of the present invention,
In a sheet post-processing apparatus equipped with a plurality of intermediate stackers, when sheets that have been continuously conveyed at high speed from an image forming apparatus are alternately received by the intermediate stacker and aligned for post-processing, a small number of sheets are printed. In the case of, and in the case of a large number of sheets, high efficiency and good matching can be performed, and productivity can be increased. Further, since the stepping motor as the drive source may be a small one with a light torque, it is effective in reducing the manufacturing cost. Further, since it is not necessary to provide an elastic member or the like on the movable matching plate, there is no influence of deformation or deterioration of the elastic member,
Good matching can be achieved, the number of parts does not increase, and the cost can be reduced.

[Brief description of drawings]

FIG. 1 is an overall configuration diagram of a copying machine including a sheet post-processing device of the present invention.

FIG. 2 is a sectional view of a sheet post-processing device.

FIG. 3 is a block diagram showing the basics of a control system.

FIG. 4 is a sectional view of a sheet discharging unit.

FIG. 5 is a plan view of a sheet discharging portion, a sectional view taken along line AA, and B.
-B sectional drawing.

FIG. 6 is a schematic plan view showing a paper aligning process.

FIG. 7 is a schematic plan view showing an operation process of the matching unit at the end of partial copying.

FIG. 8 is a flowchart showing an operation process of the matching means.

FIG. 9 is a cross-sectional view illustrating paper alignment performed by an alignment unit.

[Explanation of symbols]

 100 Copier body 400 Sheet post-processing device (FNS device, finisher) 420 (430) Second (third) transport path 422,432 Guide belt 425 (435) First (second) discharge belt 426 (436) First (Second) Tray (intermediate stacker) 426A Reference surface 427 (437) Aligning means 4271 Drive pulley 4272 Driven pulley 4273 Timing belt 4274 Movable aligning plate 4275 Guide shaft 4276 Guide 4277 Guide member 440 Sheet passing part 441, 451 Stopper 442 Transfer lever 460,470 Paper ejection means A1 Standby reference position A3, B2 Alignment position HP Home position M1, M2, M3 Motor M4 Alignment motor (stepping motor) P sheet (recording paper), sheet bundle S14 Home position sensor ST1 1st stapler ( Binding means) ST2 Second stapler (binding means) T1 First paper ejection tray (upper tray) T2 Second paper ejection tray Lee (lower tray)

Claims (2)

[Claims] 1. A feeding means for introducing and feeding a sheet carried out from an image forming apparatus, and a first tray for stacking the sheet fed from the feeding means at a predetermined position and temporarily storing it. Aligning means for aligning the sheets on the first tray in a direction orthogonal to the sheet feeding direction, stapling means for binding the bundle of sheets stacked and aligned on the first tray, and the bound sheets In a sheet post-processing apparatus including a discharging unit that transfers and discharges a bundle and a second tray that stores the sheet bundle discharged by the discharging unit, the aligning unit is provided in a direction orthogonal to the sheet feeding direction. And a reference guide surface portion that regulates one side end surface of the sheet, a movable alignment plate that is arranged to face the reference guide surface portion and that presses the other side end surface of the sheet so as to be contactable and separable, and aligns the movable alignment plate with the sheet. It is composed of drive means for reciprocating in a direction orthogonal to the feeding direction, detection means for detecting the home position of the movable aligning plate, and control means for variably controlling the drive means according to the number of the sheet bundle. When the number of sheet bundles on the first tray is larger than a predetermined number set in advance, the movable aligning plate is once returned to the home position after the binding process by the stapling unit by the control unit and the driving unit. A sheet post-processing apparatus that is controlled as described above. 2. The movable means for aligning by pressing the fixed reference guide surface portion that regulates one side end surface of the sheet and the other side end surface of the sheet that is disposed so as to face the reference guide surface portion so as to be contactable and separable. 2. The sheet post-processing apparatus according to claim 1, wherein the sheet post-processing apparatus is a sheet-one-side reference aligning means including an aligning plate.