JP2531751B2 - Sheet aftertreatment device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet post-processing apparatus which is mounted on the output side of an image forming apparatus and performs sorting alignment and binding operations for discharged copy sheets.

[Conventional technology]

A conventional sheet post-processing apparatus comprises a processing section for aligning and binding sheets and a storage tray for storing the bound sheet bundle as described in JP-A-59-78069. It was configured to be sent from the storage tray to the storage tray by the transporting means.

[Problems to be Solved by the Invention] However, in the above-described conventional sheet post-processing apparatus, in order to feed and stack the sheet bundle at the same position on the storage tray one after another, when stapled or the like,
There is a problem in that the needle portions are stacked and stacked, and the stapled peripheral portion rises, making it easy to collapse if a large number of stacks are stacked.

The one disclosed in Japanese Patent Laid-Open No. 58-47760 has a side wall around the storage tray. However, in the structure in which the side wall prevents the collapse, the size of the stored sheet must be constant. Further, particularly when aligning or binding sheets as in Japanese Patent Laid-Open No. 58-47760 with a part of them placed on a bound sheet bundle, the bulge of the needle portion allows proper alignment and binding. I was running up.

[Means (and Action) for Solving Problems]

An object of the present invention is to solve the above problems and to provide a sheet post-processing apparatus that does not collapse even when a large number of bound sheet bundles are stacked.

According to the present invention, binding means for binding a bundle of sheets, stacking means for loading the sheet bundle bound by the binding means, and moving means for moving the sheet bundle bound by the binding means to the loading means The sheet post-processing apparatus is bound by providing a stacking position changing unit that changes a stacking position of the sheet bundle with respect to the stacking unit so that the sheet stack is stacked on the stacking unit in a mutually shifted state. Even if a large number of sheet bundles are stacked, it will not easily collapse.

〔Example〕

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a diagram showing the internal configuration of an embodiment of a copying apparatus to which the present invention can be applied. In the figure, 1 is a copying apparatus main body, 200 is a pedestal having a double-sided processing function of turning over a recording medium (paper) in double-sided recording, and a multiple recording function of performing recording a plurality of times on the same recording medium. Is a circulation type document feeder (hereinafter referred to as RDF) that automatically feeds documents, and 4 is a sheet post-processing device that stacks sheets ejected from the copying machine body by aligning, folding, binding, and the like. .

A. Main body (1) In the main body 1, 101 is a platen glass on which an original is placed, 103 an illumination lamp (exposure lamp) for illuminating the original, 10
5, 107 and 109 are scanning reflection mirrors (scanning mirrors) for changing the optical path of the reflected light of the original, 111 is a lens having focusing and zooming functions, and 113 is a fourth reflection mirror (scanning mirror) for changing the optical path. . 115 is an optical system motor for driving the optical system, and 117, 119 and 121 are sensors.

131 is a photosensitive drum, 133 is a main motor for driving the photosensitive drum 131, 135 is a high-voltage unit, 137 is a blank exposure unit, 139 is a developing device, 140 is a developing roller, 141 is a transfer charger, 143 is a separation charger, and 145 is a cleaning device.

Reference numeral 151 is an upper cassette, 153 is a lower cassette, 171 is a manual paper feed port, 155 and 157 are paper feed rollers, and 159 is a registration roller. Further, 161 is a conveyor belt that conveys the recording paper on which an image is recorded to the fixing side, 163 is a fixing device that fixes the conveyed recording paper by thermocompression bonding, and 167 is a sensor used in double-sided recording.

The surface of the above-mentioned photosensitive drum 131 is composed of a photoconductor and a seamless photosensitive member using a conductor, and the drum 131 is rotatably supported by a shaft and operates in response to the pressing of a copy start key described later. Rotation is started by the order 133 in the direction of the arrow in this figure. Next, when the predetermined rotation control of the drum 131 and the potential control processing (preprocessing) are completed, the original placed on the original table glass 101 is illuminated by the illumination lamp 103 integrated with the first scanning mirror 105, The reflected light of the document is the first scanning mirror 105, the second scanning mirror 107, the third scanning mirror 109, the lens 111, and the fourth scanning mirror 11.
An image is formed on the drum 131 via 3.

The drum 131 is corona charged by the high voltage unit 135. After that, the image (original image) illuminated by the illumination lamp 103 is slit-exposed, and an electrostatic latent image is formed on the drum 131 by the known Carlson method.

Next, the electrostatic latent image on the photosensitive drum 131 is developed by the developing roller 140 of the developing device 139 and visualized as a toner image, and the toner image is transferred onto the transfer paper by the transfer charger 141 as described later. .

That is, the upper cassette 151 or the lower cassette 153
The transfer paper inside or the transfer paper set in the manual paper feed port 171 is sent to the inside of the main body apparatus by the paper feed roller 155 or 157, and is sent to the photosensitive drum 131 at a correct timing by the registration roller 159, and the latent image is transferred. The leading edge of the image is aligned with the leading edge of the transfer paper. After that, the transfer paper passes between the transfer charger 141 and the drum 131, so that the drum 131
The upper toner image is transferred onto the transfer paper. After this transfer is completed, the transfer paper is separated from the drum 131 by the separation charger 143, guided to the fixing device 163 by the conveyor belt 161, fixed by pressure and heating, and then discharged to the outside of the main body 100 by the discharge roller 165. To be done.

After the transfer, the drum 131 continues to rotate and the surface thereof is cleaned by the cleaning device 145 including a cleaning roller and an elastic blade.

B. Pedestal (200) The pedestal 200 has a deck 201 that can be separated from the main body 100 and can store 2,000 sheets of transfer paper, and an intermediate tray 203 for double-sided copying. Also, that 2,0
The lifter 205 of the deck 201 that can store 00 sheets is the paper feed roller 20.
As the transfer paper always contacts 7, it rises according to the amount of the transfer paper.

Further, 211 is a paper ejection flapper that switches between the double-sided recording side or multi-recording side path and the ejection side path, 213 and 215 are conveyance belt conveyance paths, and 217 is an intermediate tray weight for pressing the transfer paper. 211, and the transport path 213,215
The transfer paper that passed through is turned over and the intermediate tray for double-sided copying
It is stored in 203. Reference numeral 219 denotes a multiple flapper for switching between double-sided recording and multiple recording paths, which is arranged between the transport paths 213 and 215 and is rotated upward to guide the transfer paper to the multiple recording transport path 221. Reference numeral 223 denotes a multiple paper discharge sensor that detects the end of the transfer paper that passes through the multiple flapper 219. Reference numeral 225 is a paper feed roller that feeds the transfer paper to the drum 131 side through the path 227. Denoted at 3 is a discharge roller for discharging the transfer paper to the outside of the machine.

During double-sided recording (double-sided copying) or multiplex recording (multiplex copying), first, the discharge flapper 211 of the main body 100 is raised to store the copied transfer sheet in the intermediate tray 203 via the conveyance paths 213 and 215 of the pedestal 200. To do. At this time, the multiple flapper 219 is lowered during double-sided recording, and the multiple flapper 219 is raised during multiplex recording. The intermediate tray 203 can store, for example, up to 99 copy sheets. The transfer paper stored in the intermediate tray 203 is pressed by the intermediate tray weight 217.

At the time of the next-side recording or the multiplex recording to be performed next, the transfer sheets stored in the intermediate tray 203 are registered one by one by the action of the sheet feeding roller 225 and the weight 217 from the bottom to the registration of the main body 100 via the path 227. It is guided to the roller 159.

C.RDF (Recirculating Document Feeder) (2) In RDF2, 301 is a stacking tray for setting the document stack 302. First, for a single-sided document, the half-moon roller 304 and the separation roller 303 move the document stack from the bottom to the bottom. Separate one by one,
Platen glass by transport roller 305 and belt 306
After being conveyed to the exposure position 101 by way of paths I to II, it is stopped and the copying operation is started. And after copying, pass
Via IV, it is sent to path VI by large transport roller 307,
Further, it is returned to the upper surface of the original bundle 302 by the paper discharge roller 308. Reference numeral 309 denotes a recycle lever that detects one circulation of a document. When the document is started to be fed, the recycle lever is placed on the upper part of the document stack, the documents are sequentially fed, and the rear end of the last document is the recycle lever.
When passing through 309, the circulation of the original document is detected because it falls due to its own weight.

Next, for double-sided originals, copy the originals once as I and II as described above.
To III, and by switching the rotatable switching flapper 310 there, the leading edge of the document is guided to path IV, and the transport roller 305
Platen glass 1 with a full belt 306 through pass II
01 Transport on top and stop. That is, the large conveyance roller 307
Thus, the document is inverted at the route of paths III-IV-II.

Further, the number of originals can be counted by conveying the original bundle 302 one by one through the paths I-II-III-IV-VI until one cycle is detected by the recycle lever 309.

D. Sheet Post-Processing Device 4 is a sheet post-processing device which is the device of the present invention, and includes a portion 5 (hereinafter referred to as a finisher) capable of stacking, aligning and binding one or more copy sheets from the main body, and a copy sheet. Part 6 to fold each sheet in half or Z
(Hereinafter referred to as a folder) and a sheet storage unit 7 (hereinafter referred to as a stacker) capable of storing at least one copy sheet group for which alignment or binding operations have been completed.

The connection of the post-processing apparatus 4 to the image forming apparatus 1 is achieved by connecting the catching portion of the handle 9 on the side of the post-processing apparatus 4 to the receiving member 8 on the side of the image forming apparatus 1, and at the bottom of the post-processing apparatus 4. Is equipped with a caster 10. When a paper conveyance failure occurs in the image forming apparatus 1 or the post-processing apparatus 4, the handle 9 is slightly pulled up to rotate counterclockwise around the support shaft 9a so that the main body receiving member 8 and While the lock is removed, it is moved to the left to separate the image forming apparatus 1 from the post-processing apparatus 4 to facilitate the jam processing.

Next, details of the sheet post-processing apparatus will be described (second section).
Figure).

The copy sheet discharged from the discharge roller 3 of the image forming apparatus main body 1 is sent to the upper left by the pair of transport rollers 13 and 14. At this time, the first flapper 30 is at the position indicated by the solid line and guides the copy sheet together with the upper conveyance guide 11 and the lower guide 12. The copy sheet passes through the paper discharge sensor 15 and is discharged onto the mounting table 24 by the discharge lower roller 16 and the pressing roller 17. At this time, set the leading edge or the trailing edge of the copy sheet to the paper ejection sensor.
At the moment when 15 is detected, or after a lapse of a predetermined time after the detection, the speed of the discharge lower roller 16 is reduced below the steady speed and the copy paper is discharged. As a result, the consistency of the copy sheet on the mounting table 24 can be improved. Further, the paper discharge sensor 15 also functions as a detection means when the copy sheets are stuck in the paper path sandwiched by the upper guide 11 and the lower guide 12 due to conveyance failure, and 31 is attached to the paper discharge port. This is a static elimination needle that sweeps the surface of the copy sheet each time it is discharged to prevent electrification.

Further, reference numeral 18 denotes a discharge alignment belt, which is held and rotated between the tray discharge lower roller 16 and the pressing roller 17. The discharge alignment belt 18 rotates while contacting the mounting table 24,
A conveying force is applied to bring the sheet discharged above into contact with the contact plate 19. As a measure for preventing the belt from slipping, an endless rib is provided in the vicinity of the central portion inside the belt, and the rib is configured to rotate by engaging with the tray discharge lower roller. Reference numeral 19 is a backing plate, which serves as a reference surface in the paper transport direction during copy sheet alignment, and the stapling position is also substantially determined by the position of the backing plate 19.

A staple unit is arranged in a region 24 shown by a one-dot chain line in FIG. 1 or 2. The staple unit 24 is driven by an electric solenoid or a motor to drive a staple needle into a sheet bundle discharged and aligned on the mounting table 24, and perform an operation of binding the staple.

Reference numeral 22 is a positioning plate that serves as a reference for applying the copy sheet in the direction perpendicular to the paper conveyance direction (width direction). The copy sheets discharged from the tray discharge rollers 16 and 17 onto the mounting table 24 are not bound when the binding is performed, but the contact plate 19 is in the transport direction and the width aligning member 22 is perpendicular to the transport direction.
After being aligned with, it is pushed out from the rear end by the bundle conveying member 20,
It is loaded on the tray 29 of the stacker 7.

As shown in FIG. 5, the bundle conveying member 20 is an elastic member that is adhered to or integrally molded with the bundle conveying belt 21, and is mounted on the mounting table 24.
Sufficient rigidity and elasticity are ensured to convey the upper sheet bundle and to the extent that it flexes when hitting a fixed object. The side of the elastic member that hits the paper catches the edge of the paper, and a rollet 20a is provided to surely convey the bundle. In addition, the bundle conveying member 2
There is only one 0 for the bundle conveying belt 21 in FIG. 1, but two 0s may be provided at the opposite positions as shown in FIG. By attaching two of them, the time for returning the bundle conveying member 20 to the home position near the abutment plate 19 can be saved, and the speed up as a system can be achieved.

Reference numeral 32 denotes a transmissive sensor that detects the presence or absence of a copy sheet on the mounting table 24.
If it is confirmed that there is no copy sheet on the top, or if the sensor 32 does not turn off within a certain period of time after operating the bundle conveying member 20 for a group of copy sheets, it is determined that some abnormality has occurred and the image is displayed. Stop processing. Further, a sensor 33 for detecting one rotation of the bundle conveying member 20 attached to the bundle conveying belt 21 is provided near the home position of the bundle conveying member 20. This is because the bundle conveying member 20 needs to be prepared near the contact plate 19 in order to push out a group of copy sheets and then push out the next sheet group. This sensor is also a bundle conveying member even if the drive is transmitted for a time sufficient for the bundle conveying member 20 to make one rotation and return.
If 20 is not detected, it can be judged that something is wrong and the system can be stopped for safety. As described above, the bundle conveying member 20 has rigidity and elasticity such that it bends when it hits a fixed object. Therefore, after pushing out a group of sheets, the bundle conveying member 20 bends as shown by the dotted line in the second round and digs into the lower side. Stop in place to transport the next bundle.

Reference numeral 22 is a width aligning member, and the width aligning member 22 provided at two positions on the front side and the back side facing the plane of FIG.
It is possible to move the back side by driving the stepping motor, align the copy sheets discharged on the mounting table 24 in the direction perpendicular to the conveying direction, and shift the bundle in the same direction with high accuracy.

That is, every time one copy-completed sheet is discharged, at least one of the width-adjusting members 22 on the back side or the front side moves in the direction perpendicular to the paper surface of FIG. Then, by changing the movement range of the width adjusting member, the copy sheets are aligned to different positions on the mounting table 24 for each copy sheet group, and the shift is performed. Alternatively, the alignment may be performed at the same position on the mounting table 24, and when the bundle conveying member 20 pushes the sheet bundle from the mounting table 24 to the tray 29, the width aligning member 22 may be simultaneously moved to perform the shift. In any case, the sheets stacked on the tray 29 by the shift are placed in a state of being shifted in the direction perpendicular to the conveying direction for each sheet bundle. Therefore, when stacking a sheet bundle bound by stapling, the staples do not overlap each other, and the bulge can be reduced.

 Next, details of the stacker unit 7 will be described.

FIG. 4 shows a drive unit built in the stacker unit. 41
Is a vertical movement motor, which transmits its driving force to the pinion 43 via the gear 42, and allows the storage tray 29 to move up and down together with the fixed rack 44 on the main body side plate engaging with the pinion 43. Further, the guide rollers 45 and 45a are mounted on the unit of the lower portion 29 of the storage tray, and are allowed to move smoothly along the guide rail 46 fixed to the body side plate. The guide rail 46 also receives the weight of the storage tray and the weight of the stored copy sheets.

FIG. 5 is a view showing means for detecting the height of the tray 29. The copy sheets discharged from the finisher unit 5 are stacked on the tray 29, but the sheet sensor lever 47 is in contact with the stacked uppermost sheet. The seat sensor lever 47 has a fulcrum 47a on the finisher portion 5.
It has and can rotate freely around the fulcrum. Further, a sensor flag 47b is formed at the end portion on the side not contacting the paper surface, and the flag 47b is detected by the sheet level sensor 48.

FIG. 6 is a diagram showing the operation at the sheet sensor level,
(I) has a certain gap with the tray surface in the initial state. This state is considered to be, for example, a state in which the previous operator has finished processing and removed the paper from the tray. When the next operator tries to start the process, the tray is raised, and the tray is stopped in the state of (ii), that is, when the sheet level sensor is turned on. This state is the standby state, and the tray can receive copy sheets. In (iii), the sensor is ON with copy sheets stacked. When the sensor is turned on, the tray is lowered until the sensor is turned off, and stopped when the height relationship between the tray and the discharge port becomes the state of (ii). By this control, the paper surface having a constant height is always secured.

 Next, details of the folder unit 6 will be described.

When the folder portion 6 is connected, it is installed on the finisher portion 5 as shown in FIG. FIG. 7 is a detailed view of the folder portion. The discharge port 50 of the finisher unit 5 is aligned with the carry-in port 51 of the folder unit 6, and the carry-in port 52 of the finisher unit 5 is matched with the discharge port 5 of the folder unit 6.

Two pairs of conveying rollers 55, 56 are arranged in the entrance conveying path 54 of the folder unit 6, and a pair of conveying rollers 58 are arranged in the exit conveying path 57. Further, each member that constitutes the sheet folding means is arranged on the downstream side of the folding conveyance path 54, the folding means first the first folding roller 60 is arranged, and further, a second folding roller adjacent to the roller 60 is arranged. Folding roller 61
Is arranged. Further, on the downstream side of the first folding roller 60, the sheet S conveyed from the folding conveyance path 54 is
The first deflector 62 which can be switched in two directions and is guided to the folding position regulating conveyance path 63 or to the first-stage folding roller pair (60, 61) including the first and second folding rollers 60, 61. Is provided. In addition, a fixed stopper member 63 and a solenoid device are provided on the downstream side of the first folding position regulating conveyance path 63.
A movable stopper member 65 is arranged so as to project to the central portion in the conveyance path 63 when the 65a is biased. Further, on the downstream side of the pair of folding rollers (60, 61) in the first stage,
The sheet S conveyed from the pair of folding rollers (60, 61) at the first stage is conveyed to the second folding position regulating conveyance path 67, or the second folding roller 61 and the third folding roller adjacent to the roller 61. A second deflector 66 which is switchable in two directions and is guided to a second stage folding roller pair (61, 69) composed of rollers 69 is provided. A fixed stopper member 70 is disposed downstream of the second folding position regulating conveyance path 67. Further, on the downstream side of the second stage folding roller pair (61, 69),
The sheet S conveyed from the second-stage folding roller pair (61, 69) is conveyed to the third folding position regulating conveyance path 72, or the third folding roller 69 and the fourth folding roller adjacent to the third folding roller 69. A third deflector 71, which is switchable in two directions and is guided to a third stage folding roller pair (69, 73) composed of a roller 73, is provided. Further, a fixed stopper member 75 is arranged on the downstream side of the third folding position regulating conveyance path 72. A folding end conveyance path 57 is formed on the downstream side of the third-stage folding roller pair (69, 73), and the downstream side of the conveyance path 57 is connected to the front discharge roller pair 58.

E. Controller (800) FIG. 6 shows a circuit configuration example of the controller 800 of the embodiment shown in FIG. In FIG. 6, reference numeral 801 is a central processing unit (CPU) that performs arithmetic control for executing the present invention, and uses a microcomputer. Reference numeral 803 denotes a read-only memory (ROM) in which a control procedure (control program) as shown in FIG.
Controls each constituent device connected via a path according to the control procedure stored in this ROM. Reference numeral 805 denotes a random access memory (RAM) which is a main storage device used as a storage area for input data, a work storage area, or the like.

Reference numeral 807 is an interface (I / O) that outputs a control signal of the CPU 801 to the load of the tray vertical motor 301 and the like, and reference numeral 809 is an interface that inputs an input signal of the sheet detection sensor 13 and sends the input signal to the CPU 801.

808 is a solenoid that drives a folder deflector 8
10 is an interface (I / O) that outputs a control signal to a solenoid that drives the movable stop solenoid 65a. Reference numeral 811 is a key group for designating the operation mode of the copying machine, RDF, the initiator, and the folder, and instructing the start and stop of the operation.

Next, an operation example in the present embodiment will be described using a flow chart.

FIG. 9 is a flow chart for explaining the initial operation of the post-processing apparatus which is executed at power-on or when copying is started. In step S1, the number of stored sheets stored in the RAM 805 is set to 0.
Clear it, and further, in steps S2 to S4, the width adjusting member
Until step 22 (front and back) reaches the home position, the stepping motor is reversely turned on and stopped.

Next, in S5 to S7, the motor is driven and stopped until the bundle conveying member reaches the home position. Further, the tray height is checked in S8 to S10, and the tray up / down motor is turned on and stopped until the sheet level sensor is turned on. By the processes of S1 to S10, the sheet discharge from the copying machine is accepted.

Next, FIG. 10 is a flowchart for explaining the sheet post-processing operation after the start of copying. First, step S11
Then, the conveyance motor 812 that drives the pair of conveyance rollers 13, 14, 17, 36, 37, 39 is turned on, and after the sheet detection sensor 15 detects the sheet leading edge in step S12, until the sheet trailing edge is detected in step S13. Wait and start the tray storage timer in S14. After a necessary and sufficient time for the sheets to fit on the tray (step S15), the stepping motor 813 for driving the width aligning member 22 is driven by step S16, and the width is aligned by a predetermined width alignment amount (S17-). 19). In step S20, the number of stored sheets counter is incremented by 1, and in step S21, copy processing is 1
Check that the cycle has ended. For this, for example, the signal of the one-cycle detection sensor 301 by the above-mentioned RDF recycling lever may be checked. If one cycle is completed, the next stapling process (S26) is performed. When one cycle has not been completed, the width biasing member 22 is returned to the original home position (S21 to S24), and then the tray height is checked at step S25, and if the operator loads the sheets loaded on the tray. When the stack is removed, the tray is raised so that the height of the paper surface is always constant.

Next, when the end of one cycle is detected in step S21,
At step S26, the stapler motor 814 is driven to perform the stapling process, and at step S27, the completion is waited (FIG. 16 (a)). When it is finished, the tray motor 41 is lowered and turned on in step S28, and the timer of the lowered amount corresponding to the stored number counter is started in step S29. After the timer is finished in step S30, the tray motor 41 is turned off in step S31. Figure 16 (b)).

This timer value is, for example, assuming that one sheet has a thickness of 0.1 mm, the counter value is 10 mm and the value is 2 mm lower.
It is set a little higher than the number of sheets, such as a value that lowers by 3 mm.

Reverse width stepping motor 813 in step S32.
Turn it on, and start the width-shift escape counter at step S33,
The motor is turned off in step S35 after waiting for the end in step S34.

Next, in step S36, the bundle conveying member 2 that pushes out the sheet bundle
The 0 drive motor 203 is started to start the extrusion amount counter (step S37), and the counter is stopped and stopped (steps S38, S39). In S36 to S39, the stapled sheet bundle can be pushed out (Fig. 16 (c)). Then, in S40, perform the above-mentioned initial processing,
Return the positioning plate and the touching plate to the initial position, raise the trays that are slightly lower than the number of sheets in S28 to S31 described above until the level sensor turns on, and keep the position of the paper surface constant at S12. It returns and waits for the next sheet discharge (Fig. 16 (d)).

In this embodiment, when the sheet is pushed out to the tray 20, the sheet is laterally shifted so that the staples of the staples do not overlap each other, so that the periphery of the staples does not rise, and as shown in FIG. 16 (a). There is no problem even if the discharged sheets are stacked, aligned, and bound on the sheets stacked in.

Next, an operation for simultaneously discharging the first and second sheets of the second copy when processing a plurality of sheet groups will be described with reference to the flow chart of FIG. This is step S2 in FIG.
This is a process performed because the sheets of the next cycle are not discharged onto the mounting table 24 during the operation after 6 onward.

From the main body in step S41 during operation after step S26
When the first sheet of the second copy is discharged, the first flapper solenoid 815 (Fig. 8) is activated in step S42 to
The flapper 30 is moved to the position indicated by the broken line. The sheet is guided by the first flapper 30 to the path formed by the guide members 34 and 35. At this time, the second flapper 38 is in the position shown by the solid line in the figure, and the sheet is conveyed around the large roller 36, guided by the elastic guide 40, and gripped by the large roller 36 and the roller 41. After the leading edge of the sheet is detected by the sensor 39 of the return path 41 (step S43), after a predetermined time has elapsed (step S43).
44, 45) and the large roller clutch 816 (FIG. 8) for switching the transmission of the drive of the large roller 36 is turned off at step S46. The first sheet stops when the leading edge of the first sheet is located immediately before the sheet detection sensor 15 in the merging path 43. Then, in preparation for the second sheet, the first flapper solenoid 815 is turned off in step S47 to return the first flapper 30 to the position indicated by the solid line.
The second sheet is conveyed between the guides 11 and 12 and reaches the merging path 43. Waiting for a predetermined time after the leading edge of the second sheet is detected by the sheet detection sensor 15 at step S48 (steps S49, S50), the leading edge of the second sheet is nipped by the discharge roller pair 16,17. After that, in step S51, the large roller clutch 816 is turned on to rotate the large roller 36. The first sheet is conveyed by the rotation of the large roller 36, and is ejected in the state where it overlaps with the sheet of the second root in the merging path 43.

However, since the second upper sheet is slightly ahead, it is ejected with a slight deviation. This is because the first sheet on the lower side is pulled in first when the sheet is aligned with the contact plate 19 by the discharge alignment belt 18 after the sheet is discharged,
This is so that the second upper sheet can be pulled in later. When the upper and lower first and second sheets are completely overlapped and discharged, the upper second sheet may be drawn first and the lower first sheet may not be drawn.

The third sheet is conveyed through a path sandwiched by the guide plates 11 and 12, and thereafter, the sheets corresponding to the number of originals are stacked on the mounting table 24.

Unlike the first copy, the first copy of the second copy is not a normal path and is rotated around the large roller 36 to be conveyed in the return path 42 after the first copy is completely discharged to the mounting table 24. While the binding means is operated or the aligned copy sheet group is stacked on the stacker tray 29 by the bundle pressing member, 2
If the first pass of the set is stocked on the return pass 42, 1
It is not necessary to provide a waiting period between the image formation of the first copy and the image formation of the second copy, and the time is shortened and the productivity of the entire system is improved.

When all the copies of the second copy are completed, the binding means is selectively operated, and then, the sheets are stacked on the stacker tray 29 so as to be distinguished from the first copy.

FIG. 12 is a top view around the stacker tray 29. The copy sheet group A for the first copy is stacked on the stacker tray 29, and the copy sheet group for the second copy is the bundle pressing member 20.
At the same time, it is pushed to the left by and is shifted to the back side or the front side (the front side in FIG. 3) by the width biasing members 22a and 22b. The copy sheet group B for the second copy pushed out in this manner is stacked with a shift from the first copy by the shift amount of the width-shifting member, and is distinguished from the first copy.

As for the third copy, the first sheet is made to stand by in the return path 42 and the first and second sheets are discharged in the same manner as the second copy. Then, when the stacker tray 29 is loaded, the stacker tray 29 is pushed out to a position deviated from the second copy. The deviation may be different between the first copy and the second copy, or may be returned to the position of the first copy and have only two positions, an odd part and an even part.

Here, the movement of the width aligning member 22 will be described. Fig. 13 shows the first
In the left view of the figure, 22a is a front side width biasing member, and 22b is a back side width biasing member. Further, 24 is a stapler which is a binding means, and staples at the position of the arrow.

First, the case where the keyboard 811 is instructed to operate the binding (staple mode) will be described. When the copy paper is discharged onto the mounting table 24, the front side is fixed at the position of 22a, and the back side is at the position of the width + α of the copy paper behind 22a. To α min 22a
Move towards and align. The value of α depends on the performance of the discharging machine, and the smaller the value of α, the faster the speed of the entire system.

The copy sheet group aligned with the front side 22a as a contact is stapled and pushed out as it is.

After being stapled in the same manner as described above, the second portion is guided by the width-adjusting members 22 on both sides, pushed out while shifting to the inner side, and pushed out at the positions 22a ', 22b'. As a result, the first and second sets are stacked on the stacker tray 29 in a form shifted by the difference between 22a, b and 22a ', b', and the distinction between the bundles can be recognized. This shift amount is changed by, for example, alternately changing the count amount of the counter in steps S33 and S34 of FIG. When stapling, unless the stapler 24 moves in the front-back direction (the left-right direction in FIG. 4), the width-adjusting member on the front side needs to be in 22a when the copy sheet is ejected, so that the distance between 22a 'and 22a. The shorter the, the faster the speed.

A case where the binding means is not used (non-staple mode) will be described. In this case as well, the home position of the width aligning member that also receives the discharged paper is aligned on the front side 22a. 22a, 2
After the alignment is completed in 2b, the sheet is not pushed out at that position but pushed out while shifting to the front or the back side, for example, while being shifted to the back side, it is loaded on the tray at the positions 22a 'and 22b'. Second
The second part shifts to the front and loads at 22a ″ and 22b ″ positions. If you do not push out at home position, combining pushing out at home position and shifting and pushing out will cause waste of time, depending on whether the time to return to home position is shifted or not. I will end up.

Now, in order to distinguish the first copy and the second copy, a difference in shift amount of β is required. Compared to the combination of pushing out at home position and pushing out by β, the combination of pushing out from home position by β / 2 to the left and pushing out by β / 2 to the right always pushes back to home position by β. It is constant for only / 2 minutes, and there is no waste of time, leading to speedup as a whole.

 Next, the operation when using the folder 6 will be described.

The second when the folding mode is selected by the keyboard 811
The flappers 30, 38 in the figure are displaced to the positions shown by the dotted lines,
The copy sheet conveyed from the discharge roller 3 of the main body 1 passes through the conveying roller 13 and then is guided to the folder portion through the lower conveying path 35.

The sheet S is conveyed along the folding conveyance path 54 in FIG.
By the rotation of the folding roller 60, the sheet is conveyed to the first deflector 62.

When the half-fold mode is selected, the first
The deflector 62 is switched to the side of the first folding position regulating conveyance path 63 by the solenoid 810 operated by the signal of the control circuit 801, and the sheet S is conveyed to the first folding position regulating conveyance path 63.
And the leading edge of the sheet S is conveyed to the fixed stopper member 64.
Abutted against. At that time, the solenoid device 65a that is interlocked with the movable stopper member 65 is in a non-excited state, and the movable stopper member 65 is held in a state in which it does not protrude into the folding position regulating conveyance path 63. Then, as shown in FIG. 14 (a), a loop X of the sheet S is formed at the central portion of the sheet S by the contact of the fixed stopper member 64 of the sheet S. As shown in b), it is sandwiched by the pair of folding rollers (60, 6) in the first stage, and a fold line is formed in the central portion of the sheet S. The sheet S folded in two in this way is switched to the second stage folding roller pair (61, 69) side and the second stage deflector 66 and the third stage folding roller pair (69, 73) side are switched. 3 is guided by the deflector 71 and the second stage folding roller pair (61, 69), the third stage folding roller pair (69, 73) and the outlet transport path 57 are transported,
The sheet is conveyed to the sheet outlet 53 by the rotation of the pair of conveying rollers 58.

Further, as shown in FIG. 15 (b), when the Z-folding mode is selected, the first deflector 62 is switched to the first folding position regulating conveyance path 63 side, and the solenoid device is further provided.
The movable stopper member 65 is projected into the folding position regulating conveyance path 63 by exciting the 65a. Then, the sheet S is guided by the first deflector 62, and the first folding position regulating conveyance path is formed.
The front end of the sheet S is conveyed to 63 and the movable stopper member
Abut on 64. Then, a loop is formed in a portion of about 1/4 from the leading edge of the sheet S, and the loop of the sheet S is sandwiched between the pair of folding rollers (60, 61) in the first stage, and
A first fold is formed at the / 4 portion. Further, the sheet S on which the first fold line is formed is guided to the second deflector 66 switched to the second folding position regulating conveyance path 67 side,
The sheet S is conveyed to the second folding position regulating conveyance path 67, and the leading end of the sheet S is brought into contact with the fixed stopper member 70. Then, a loop is formed at the end of the two-sheet stack by the first fold of the sheet S, the loop of the sheet S is sandwiched between the pair of folding rollers (61, 69) in the second stage, and the two sheets of the sheet S are stacked. A second crease is formed at the end of the stack and Z
It becomes a folded sheet. Further, the sheet S is the third deflector 71 which is switched to the side of the pair of folding rollers (69, 73) in the third stage.
And is conveyed through the third stage folding roller pair (69, 73) and the folding exit conveying path 57, and is conveyed to the sheet discharge port 53 by the rotation of the conveying roller pair 58.

Further, as shown in FIG. 15 (c), when the back Z-folding mode is selected, the first deflector 62 is switched to the first-stage folding roller pair (60, 61) side, and the second The deflector 66 is switched to the second folding position regulating conveyance path 67 side, and the sheet S is moved to the second folding position regulating conveyance path by the deflectors 62, 66 and the first stage folding roller pair (60, 61). The sheet S is conveyed to 67, and the leading edge of the sheet S is a fixed stopper member.
Abut on 70. Then, a loop is formed in a portion of about 1/4 from the leading edge of the sheet S, and the loop of the sheet S is sandwiched between the pair of folding rollers (61, 69) in the second stage, and
A first fold line is formed on the back side of the / 4 portion with respect to the Z fold. Further, the sheet S on which the first fold is formed is guided to the third deflector 61 switched to the side of the third folding position regulating conveyance path 62 and conveyed to the third folding position regulating conveyance path 62. Then, the leading end of the sheet is brought into contact with the fixed stopper member 65. Then, a loop is formed at the end of the two-sheet stack by the first fold of the sheet S, and the loop of the sheet S is the third-stage folding roller pair (69, 73).
And a second fold line is formed on the back side of the Z-fold at the end of the two-sheet stacking of the sheet S to form a back Z-fold sheet. Further, the sheet S is conveyed through the folding exit conveyance path 57 and is conveyed to the sheet discharge port 53 by the rotation of the conveyance roller pair 58.

[Other Examples]

In the above-described embodiment, the reference position of the alignment width aligning member is the same regardless of whether the staple mode or the non-staple mode is 22a in FIG. However, in the staple mode, it is necessary to move the copy sheet to the stapler position, whereas in the non-staple mode, the reference position for the width alignment should be set independently of the stapler position.

Therefore, in the non-staple mode, the width-deviation time can be omitted by providing the width-deviation reference wall near the paper traveling reference.

Further, it is possible to develop the above concept and perform speed-up in the form of taking offset into consideration. However, this is also limited to the no staple mode. 22a in FIG. 13 in the embodiment
22a 'or 22a "is adjusted by adjusting once to the left side, while offsetting to the left (back) side is performed.
When b "is used as the reference wall and the offset is made to the right (front) side, a method of moving to the offset position while aligning with 22a" as the reference wall can be considered.

In the above-described embodiment, the width aligning member 22 is used to align the sheet bundle and to perform the offset when the stacker 7 is pushed out to the tray 29. However, the present invention is not limited to this. The sheets are aligned and pushed out at a predetermined fixed position, and the stacker 7 may be horizontally moved in a direction perpendicular to the sheet pushing direction every time the sheets are pushed out. This horizontal movement must be performed before the next sheet is discharged. By reciprocally moving the stacker 7 in the horizontal direction, the sheets are placed in a state of being shifted in a bundle, and the staples do not overlap each other.

Further, the present invention can be implemented even when the binding means and the stacking means are not arranged close to each other as in the above-described embodiment. For example, even if the sheet post-processing device described in Japanese Patent Laid-Open No. 59-78069 has a conveyance path between the binding means and the stacking means, after the sheets are bound, the sheets are selectively moved in the width direction. It may be sent to the loading means via the transport path. Further, the stacking means may be moved in the horizontal direction each time the sheet bundle is sent, and a means for shifting the sheet bundle in the width direction may be provided in the conveying path.

〔The invention's effect〕

As described above, according to the present invention, the stapled sheet bundles are stacked so that the staple-stitched portions do not overlap each other. In addition, the periphery of the stapled portion does not rise to an extreme level, which prevents a stack of the next sheet from being stacked.

[Brief description of drawings]

FIG. 1 is an overall configuration diagram when a sheet post-processing apparatus according to an embodiment of the present invention is connected to an image forming apparatus, FIG. 2 is a detailed view of a finisher portion, and FIG. 3 is a detailed view of a bundle pressing member. 4 is a structural diagram of the stacker, FIGS. 5 and 6 are detailed diagrams of the seat level sensor, FIG. 7 is a configuration diagram of the folder,
FIG. 8 is a control block diagram of the sheet post-processing apparatus, and FIGS.
FIG. 11 is a flow chart, FIGS. 12 and 13 are operation explanatory views of the width-adjusting member, FIGS. 14 and 15 are operation explanatory views of the folder, and FIG. 16 is operation explanatory views of the stacker and the bundle pressing member. Is. 4 ... Sheet post-processing device 5 ... Finisher 7 ... Stacker 16 ... Tray discharging lower roller 17 ... Osaekoro 18 ... Discharging alignment belt 19 ... Pushing plate 20 ... Bundle pushing member 21 ... Bundle conveying belt 22 …… Width-adjusting member 23 …… Stapler 24 …… Standing table 29 …… Stuck tray

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Nobutaka Utsu 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Takeshi Honjo 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Incorporated (56) References JP 60-142359 (JP, A) JP 63-109448 (JP, A)

Claims (3)

(57) [Claims] 1. A binding means for binding a bundle of sheets, a stacking means for stacking the sheet bundle bound by the binding means, and a moving means for moving the sheet bundle bound by the binding means to the stacking means. A sheet post-processing apparatus comprising: stacking position changing means for changing the binding portion position of the sheet bundle with respect to the stacking means so that the binding portions of the sheet bundle are stacked in a state of being shifted from each other. 2. The stacking position changing means is a shift means for shifting and stacking the sheet bundle on the accumulating means so that the binding portions of the sheet bundle stacked on the stacking means do not overlap each other. The sheet post-processing device according to item 1. 3. The sheet post-processing according to claim 1, wherein the stacking position changing unit is a unit that relatively changes the position of the sheet bundle with respect to the binding unit so that the binding position of the binding unit is displaced. apparatus.