JP2001026345A - Sheet processing device and image forming device equipped with sheet processing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a sheet processing device capable of loading Z-folding sheets properly on a processing tray. SOLUTION: A Z-folding sheet P to be transferred is loaded on a processing tray 630 through a pair of transfer rollers 523. In addition, the Z-folding sheet P is discharged on a stack tray 700 through a discharging roller 61. The size of the Z-folding sheet to be discharged is taken as X, a distance from the pair of transfer rollers to the discharging roller is taken as A, a distance from the pair of transfers rollers to the rear end of the Z-folding sheet P that is discharged is taken as α, and a distance from the rear end of the Z-folding sheet to the inside folding part PM of the Z-folding sheet P is taken as X/2. The sheet discharging speed of the pair of transfer rollers can be controlled by a control device (control means) so that A can satisfy A>(X/2+α).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet processing apparatus, and more particularly to, for example, stacking and aligning sheets discharged by a pair of conveying rollers on a processing tray, and stacking a sheet bundle by the discharging roller pair. The present invention relates to a sheet processing apparatus provided with a retractable tray for holding a lower side of a sheet bundle during stacking, and an image forming apparatus provided with the same.

[0002]

2. Description of the Related Art Conventionally, a sheet to be conveyed is discharged onto a processing tray (first stacking means) by a pair of conveying rollers, aligned by an aligning means, bound by a binding means, and then discharged by a discharging roller (a second discharging means). ), There is known a sheet processing apparatus in which sheets are sequentially stacked on a stack tray (second stacking means). In addition to normal sheets, Z-folded sheets may be stacked and aligned on the processing tray and discharged to the stack tray.

FIG. 12A shows a Z-folded sheet.
This shows a state where the sheet is conveyed (discharged) to the processing tray. In the figure, the conveyed Z-fold sheet is discharged with the image facing downward, that is, face-down.
In this case, the folded portion inside the Z-folded sheet is located below the sheet as shown.

[0004]

In the above conventional example,
A is the distance from the conveying roller pair 523 to the discharge roller 610a, α is the distance from the conveying roller pair 523 to the rear end of the Z-folded sheet discharged from the conveying roller pair 523, and the length of the Z-folded sheet is X. Assuming that the distance from the rear end to the folded portion inside the Z-folded sheet is X / 2, the conveying roller pair 523
Is too fast, that is, A <X / 2 + α
12B, the folded portion inside the Z-folded sheet is positioned outside the discharge roller 610 in FIG. 12B and is caught by the discharge roller 610, and the Z-folded sheet is processed by the processing tray 630.
May not be properly loaded on top.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a sheet processing apparatus in which a Z-folded sheet can be properly stacked face-down on a first stacking means.

[0006]

The invention according to claim 1 is
First discharging means capable of discharging the conveyed Z-folded sheet, first discharging means driving means for driving the first discharging means, and control for controlling the driving speed of the first discharging means driving means Means, first loading means for loading sheets discharged by the first discharging means, second discharging means for discharging a sheet bundle on the first loading means to second loading means,
In the Z-folded sheet immediately before loading on the first loading means, the distance from the first discharging means to the second discharging means is A, and the Z discharged from the first discharging means is Z. Assuming that the distance to the rear end of the folded sheet is α, the length of the Z-folded sheet is X, and the distance from the rear end of the Z-folded sheet to the folded portion inside the Z-folded sheet is X / 2, A controls the discharge speed of the first discharge means so that A satisfies A> (X / 2 + α).

In the invention according to a second aspect, the Z-folded sheet is discharged face-down to the first stacking means,
The inside folded portion of the Z-folded sheet is located on the lower side.

According to a third aspect of the present invention, there is provided a first discharging means capable of discharging a conveyed Z-fold sheet, a first discharging means driving means for driving the first discharging means, and a first discharging means for driving the first discharging means. Control means for controlling the drive speed of the discharge means drive means;
A first stacking unit for stacking the sheets discharged by the discharging unit, and a second discharging unit for discharging the sheet bundle on the first stacking unit to the second stacking unit. In the Z-folded sheet immediately before loading on the first stacking means, the distance from the first discharging means to the second discharging means is A, the length of the Z-folded sheet is X, and the distance after the Z-folded sheet is X. Assuming that the distance from the end to the folded portion inside the Z-folded sheet is X / 2, A satisfies A> X / 2.

According to the above construction, when the Z-folded sheet is discharged by the first discharging means, the Z-folded sheet is discharged by the first discharging means at a speed satisfying A <X / 2 + α. Discharged on loading means. Thereby, the folded portion on the inner side of the Z-folded sheet is always loaded on the first stacking device while being located on the inner side (the first discharging device side) of the second discharging device, and the inner folded portion is The phenomenon of being caught by the second discharging means is eliminated, and the Z-folded sheet is properly loaded on the first loading means.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. The main part of the sheet processing apparatus according to the present invention is particularly shown in FIG.

FIG. 1 is a sectional view showing the internal structure of a copying apparatus 1000 as an image forming apparatus to which the sheet processing apparatus of the present invention can be applied. The copying apparatus 1000 includes a document feeding unit 100, an image reader unit 200, and a printer unit 30.
0, a folding section 400, a finisher 500, a saddle stitcher 800, an inserter 900, and the like. Folding processing unit 400, saddle stitcher 800, inserter 9
00 etc. can be optionally equipped.

Referring to FIG. 1, on a tray 1001 of the document feeding unit 100, the user is in an upright state when viewed from a user, and
It is assumed that a document is set in a face-up state (a state where an image is formed is facing upward), and the binding position of the document is located at the left end of the document. Documents set on the tray 1001 are sequentially moved left by one by one from the top page by the document feeding unit 100 (in the direction of the arrow in the figure).
That is, the sheet is conveyed with the binding position at the leading end. Then, the original is further placed on the platen glass 102 through the curved path.
The paper is conveyed from left to right on the top, and then
12 is discharged. At this time, the scanner unit 104 is in a state of being held at a predetermined position, and the reading process of the document is performed when the document passes from the left to the right on the scanner unit 104. The above-mentioned reading method is referred to as "moving original reading". Original is platen glass 10
2 passes through the scanner unit 104.
And the reflected light from the original is guided to an image sensor 109 via mirrors 105, 106 and 107 and a lens 108.

The original document conveyed by the original feeding unit 100 may be temporarily stopped on the platen glass 102, and the original reading process may be performed by moving the scanner unit 104 from left to right in this state. This reading method is referred to as original fixed reading. When reading a document without using the document feeding unit 100, the user
The document feeding unit 100 is lifted, and the document is set on the platen glass 102. In this case, the fixed original reading described above is performed.

The image data of the document read by the image sensor 109 is subjected to predetermined image processing and sent to the exposure control unit 110. Exposure control section 110 outputs a laser beam according to the image signal. The laser beam is scanned by the polygon mirror 110a while the photosensitive drum 111 is being scanned.
Irradiated on top. On the photosensitive drum 111, an electrostatic latent image corresponding to the scanned laser beam is formed.

The electrostatic latent image formed on the photosensitive drum 111 is developed by a developing unit 113 and is visualized as a toner image. On the other hand, the recording paper is a cassette 114, 115,
The sheet is conveyed to the transfer unit 116 from one of the manual sheet feeding unit 125 and the double-sided conveyance path 124. Then, the visualized toner image is transferred to recording paper in the transfer unit 116. The recording paper after the transfer is subjected to a fixing process in a fixing unit 117.

The recording paper that has passed through the fixing unit 117 is once guided to a path 122 by a flapper 121, is switched back after the trailing end of the recording paper has passed through the flapper 121, and is conveyed to a discharge roller 118 by the flapper 121. Then, the recording paper is discharged from the printer unit 300 by the discharge roller 118. As a result, the surface on which the toner image has been formed can be discharged from the printer unit 300 in a face-down state. This is referred to as reverse paper discharge.

As described above, when the recording paper is discharged face-down to the outside of the apparatus, the image forming process is performed sequentially from the first page, for example, when the image forming process is performed using the document feeding unit 100, When performing image forming processing on image data from a computer, the page order can be made uniform.

Note that O conveyed from the manual paper feeder 125
When an image forming process is performed on a hard sheet such as an HP sheet, the printer unit 300 is driven by the discharge roller 118 with the surface on which the toner image is formed facing upward (face up) without guiding the sheet to the path 122. Discharged from

When image forming processing is performed on both sides of the sheet, the sheet is guided straight from the fixing section 117 toward the discharge roller 118, and the sheet is switched back immediately after the rear end of the sheet has passed through the flapper 121. Flapper 12
1 leads to a double-sided conveyance path.

Next, the configurations of the folding section 400 and the finisher 500 will be described with reference to FIGS.

The folding section 400 has a transport path 131 for introducing the sheet discharged from the printer section 300 and guiding the sheet to the finisher 500 side. On the transport path 131, transport roller pairs 130 and 133 are provided. The switching flapper 135 provided near the transport roller pair 133 is for guiding the sheet transported by the transport roller pair 130 to the folding path 136 or the finisher 500 side.

When the sheet is to be folded, the switching flapper 135 is switched to the folding path 136 to guide the sheet to the folding path 136. The sheet guided to the folding path 136 is conveyed to folding rollers 140 to 1042, and is folded into a Z shape. On the other hand, when the folding process is not performed, the switching flapper 410 is switched to the finisher side 500, and the sheet discharged from the printer unit 300 is transferred to the transport path 131.
Through the direct.

The sheet conveyed along the folding path 136 is folded by the folding rollers 140 and 141 in a loop formed by abutting the leading end against the stopper 137. By folding the loop formed by abutting the bent portion against the upper stopper 143 by the folding rollers 141 and 142, the sheet is Z-folded. This Z
The folded sheet is transferred to the transport path 131 via the transport path 145.
And is discharged by the discharge roller 133 to the saddle stitcher 800 and the finisher 500 on the downstream side.

The sheet sent from the folding section 400 is
Switching between the finisher 500 and the saddle stitcher 800 is performed by a switching flapper (switching means) 235. First, the configuration of the finisher 500 will be described.

The finisher 500 includes a folding processing section 400
Fetching sheets from the printer unit 300 conveyed via the printer unit, aligning the fetched sheets and binding them as one sheet bundle, staple processing (stapling processing) for stapling the rear end side of the sheet bundle, and sorting This is for performing sheet processing such as processing, non-sort processing, and bookbinding processing.

As shown in FIG. 2, the finisher 500
Has an inlet roller pair 232 for taking the sheet conveyed through the folding processing unit 400 into the inside of the apparatus. Downstream of the entrance roller pair 232, a switching flapper 2 for guiding a sheet to a finisher pass or a lower binding pass.
35 are provided.

The sheet guided to the finisher path is conveyed toward a buffer roller 513 via a pair of conveying rollers 510. Note that the transport roller pair 510 and the buffer roller 513 are configured to be capable of normal and reverse rotation.

Conveying roller pair 510 and buffer roller 51
3, a punch unit 512 is provided. The punch unit 512 is operated as needed, and performs a punching (perforation) process near the rear end of the sheet conveyed via the conveying roller pair 510.

The buffer roller 513 includes the transport roller 51
The roller is a roller capable of winding a predetermined number of sheets conveyed through the roller 0. The sheet is wound by the pressing roller 515 while the buffer roller 513 is rotating. The sheet wound around the buffer roller 513 is conveyed in a direction in which the buffer roller 513 rotates.

In the middle of a buffer path 516 formed on the peripheral surface of the buffer roller 513, a switching flapper 5 is provided.
17 is provided below the switching flapper 5.
20 are provided. The switching flapper 517 is for peeling the sheet wound around the buffer roller 513 from the buffer roller 513 and leading the sheet to the non-sort path or the sort path 521 on the sample tray 701 side.

The switching flapper 520 is connected to the buffer roller 5.
13 is wound on a buffer roller 513.
And is guided to the sort path 521. Further, it is for guiding the sheet wound around the buffer roller 513 to the buffer path 516 in the wound state. The sheet guided to the non-sort path by the switching flapper 510 is discharged onto the sample tray 701 via the discharge roller pair 519.

On the other hand, the sheet guided to the sort path 521 by the switching flapper 517 is placed on a processing tray (first stacking means) 630 as an intermediate tray via a pair of conveying rollers (first discharging means) 522 and 523. Be loaded. The sheet group stacked in a bundle on the processing tray 630 is subjected to alignment processing and stapling processing in accordance with settings from the operation unit 1 (FIG. 7), and thereafter, a discharge roller (second discharge unit) 610a. , 610b onto the stack tray (second stacking means) 700.

The stapling process described above is performed by the stapler 601. The stack tray 700 is
It is configured to be able to run in the vertical direction. The control of the speed of the Z-folded sheet P by the conveying roller pair 523 is as follows.
This is a main part of the present invention and will be described with reference to FIG.

Next, the configuration of the saddle stitcher 800 will be described.

The sheet switched downward by the switching flapper 235 is selected by the flapper 236 in accordance with the size, and is carried into the storage guide 237 of the saddle stitcher 800, and the leading end of the sheet is movable. The sheet is conveyed until it comes into contact with the sheet positioning member 239. Further, two pairs of staplers 240 are provided at an intermediate position of the storage guide 237, and an anvil is provided at a position facing the stapler 240. The stapler 2
Reference numeral 40 is configured to cooperate with the anvil to bind the center of the sheet bundle.

Downstream of the stapler 240, folding roller pairs 242 and 243 are provided.
A protruding member 241 is provided at a position facing 42 and 243. By projecting the protruding member 241 toward the sheet bundle stored in the storage guide 237, the sheet bundle is pushed out between the pair of folding rollers 242 and 243, and is folded by the pair of folding rollers 242 and 243. Then, the sheet is discharged from the discharge tray 2 via the discharge roller 245.
It is discharged to 46.

When the sheet bundle bound by the stapler 240 is folded, the sheet positioning member is positioned such that the staple position of the sheet bundle is at the center position (nip point) of the pair of folding rollers 242 and 243 after the stapling process is completed. 239 is lowered a predetermined distance from the place where the staple processing is performed. Thus, the sheet bundle can be folded around the position where the stapling process has been performed.

Next, the inserter 900 provided above the finisher 500 will be described with reference to FIGS.

An inserter 900 is provided on the finisher 500. The inserter 900 is for inserting a sheet (insert sheet) different from a normal recording sheet into the first page, the last page, or the middle page of the recording sheet. This is for inserting an insert sheet or a cover sheet between the sheets.

An inserter 900 feeds a sheet set on an insert tray (mounting means) 901 to any of a sample tray 701, a stack tray 700, and a discharge tray 246 without passing through the printer unit 300. It is. In the present embodiment, a cover or a sheet I for an insert sheet is set on the insert tray 901 of the inserter 900 in a face-up state (a state in which the front surface is up) by the user. By the user, the sheet bundle I stacked on the insert tray 901 is sequentially separated one by one and conveyed to the finisher path 233 or the bookbinding path 234. The configuration of the inserter (paper feeder) 900 is shown in FIG.
This will be described below.

The bundle of insert sheets I (FIG. 3B) placed on the insert tray 901 is separated by a paper feed roller (paper feed means) 902 into a separation section constituted by a transport roller 903 and a separation belt 904. Conveyed. 923 is
3 illustrates an alignment plate that aligns a sheet bundle. Then, the sheet is separated one by one from the uppermost sheet by the conveying roller 903 and the separation belt 904. Then, the separated sheet is pulled out by a pull-out roller pair 905 close to the separation unit, and is conveyed by a conveying roller 921 to a sheet conveying path 922.
Is transported. The inserted inserter sheet I is carried into the carrying-in port 230a of the sheet carrying path 230 of the apparatus main body from the discharge port 922a. The sheet conveyance path 922 near the a discharge port 922a and the sheet conveyance path 230 are substantially formed, and the discharge port 922a and the carry-in port 230a join at a position facing each other.

An auxiliary tray 930 is provided at an end of the inserter tray 901 so as to be rotatable about a support shaft 931. 3A shows a state in which the auxiliary tray 930 is closed at the storage position, FIG.
FIG. 3C shows a cross section taken along line CC of FIG. When the insert tray 239 is used, the insert tray 239 is rotated so as to be opened to the operating position as shown in FIG.

The auxiliary tray 930 has a mounting plate 930a and a rib 930b integrally provided on the back surface thereof. As shown in FIG. 3C, the height of the rib 930b is
When the auxiliary ratio tray 930 is at the storage position shown in FIG.

As a result, in a state where the auxiliary tray 930 is closed as shown in FIG. 9A (storage state), the inserter sheet I cannot be placed on the inserter tray 901 and the inserter tray 901 is used. In this case, the auxiliary tray 930 must be used in an open state.

In this manner, by making the paper supply impossible in the state where the auxiliary tray 930 is closed, it is possible to prevent in advance the paper supply failure which occurs when the large size sheet is fed in the state where the auxiliary tray 930 is forgotten to be opened. be able to.

Further, the ribs can function as a handle when changing the auxiliary tray 930. Further, when the apparatus is not used, by closing the auxiliary tray 930, it is possible to reduce the size of the apparatus and improve the visibility of the sample tray 701 (FIG. 2) below.

FIG. 7 is a block diagram of the copying apparatus 1000. The CPU circuit unit 150 has a CPU (not shown), and according to the control program stored in the ROM 151 and the settings of the operation unit 1, the document feed control unit 101, the image reader control unit 201, the image signal control unit 202, the printer The control unit 301, the folding process control unit 401, the finisher control unit 501, and the external I / F 203 are controlled. The document feed control unit 101 controls the document feed unit 100, the image reader control unit 201 controls the image reader unit 200, the printer control unit 301 controls the printer unit 300, and the folding process control unit 4.
01 denotes the folding processing unit 400 and the finisher control unit 501.
Controls the finisher 500. The operation unit 1 includes a plurality of keys for setting various functions related to image formation, a display unit for displaying a setting state, and the like, and sends a key signal corresponding to an operation of each key by a user to the CPU circuit unit 150. At the same time, the corresponding information is displayed on the display unit based on the signal from the CPU circuit unit 150.

The RAM 152 is used as an area for temporarily holding control data and as a work area for operations involved in control. An external I / F 203 is an interface between the copying apparatus 1000 and an external computer 204,
The print data from the computer 204 is developed into a bitmap image, and the image signal
Output to 2. Also, an image sensor (not shown) is provided from the image reader control unit 201 to the image signal control unit 202.
Is output. The printer control unit 301 outputs the image data from the image signal control unit 202 to the exposure control unit (not shown) 110.

Next, a method for setting an operation mode will be described with reference to FIG. 8 (a) and 8 (b)
Shows a screen displayed on the display panel of the operation unit 1 of the copying apparatus main body 1000. The screen is a touch panel, and the function is executed by touching the frame of the displayed function.

Next, the processing tray section and the retractable tray section will be described with reference to FIGS.

In FIG. 4, reference numerals 605 and 606 align the side portions of the sheet bundle stacked on the processing tray 630, and racks 607 and 609 integrated with the respective bundles can be moved by independent drive motor pinions. 603 is a stacked sheet (or sheet bundle)
The rear end regulating plate 616 that retracts to the chain line position around the support shaft 602 during the binding process of the sheet bundle by the stapler 601 is aligned in the arrow direction (clockwise direction) around the support shaft 615 during the binding process of the sheet bundle by the stapler 601. ) To rotate the processing tray 6
A paddle 525 for sweeping the sheets loaded on the sheet 30 to the rear end regulating plate 603 is rotated by the rotation of the discharge roller 523 to indicate a flexible knurl belt 525 for moving the sheet to the rear end regulating plate 603. . The operating member 52 of the solenoid 526 is provided inside the knurl belt 525.
7 is engaged, and when the solenoid 526 is turned on, from the operating position indicated by the solid line,
It retreats to the chain line position (retreat position).

The discharge rollers 610a and 610b are driven by a discharge motor M11 so as to be able to rotate forward and reverse. The upper discharge roller 610b is rotatably mounted on a free end of a swing member 612. The swing member 612 is rotatably supported by a support shaft 611 driven by the swing motor 13 and swings by rotation of a cam 613 driven by the swing motor M13.

4 and 5, below the processing tray 630, there is arranged a retractable tray 620 which can move forward and backward in the arrow X direction.
21 is movable along a guide 626 provided on the same. The base of a drive lever 622 is pivotally attached to the frame 621 by a support shaft 623. Haunting tray 620
A guide groove 624 is formed in a base portion of the drive lever 622 in a direction intersecting with a sheet conveying direction (a direction in which the retractable tray 620 advances and retreats). The guide groove 624 is rotatably provided at a free end of a drive lever 622. Roller 625 is movably mounted.

When the drive lever 622 rotates in the direction of arrow 627, the retractable tray 620 projects from the solid line position to the chain line position in FIG. The sheet bundle is supported from the side to stably discharge the sheet bundle.

FIG. 6 shows an example of a mechanism for moving the stopper of the sheet bundle discharged from the saddle stitcher 800.

On the discharge tray 246 (FIG. 2), a bottom plate 252a of the stopper 252 is provided movably in the discharge direction, and a guide groove 256 provided on the bottom plate 252a is slidably supported by the guide rib 255. . The rotational driving force of the stopper motor M15 is transmitted to the gear 261 integral with the pulley 259 via the output shaft and the integrated pulley 257, the belt 260, and the pulley 259, and further, the two-stage gears 262 and 267 mesh with the gear 261. Is transmitted to The gear 263 meshes with a rack 262b formed on the side of the bottom plate 252a. Thus, the forward and reverse rotation of the stopper motor M15 causes the stopper 252 to rotate.
Can be freely set in the discharge direction of the bound sheet bundle.

Next, the stacking and discharging of the sheet bundle to the processing tray 630 and the discharging tray 24 of the saddle stitcher 800 are performed.
The basic operation of discharging the bound sheet bundle to the sheet bundle 6 will be described with reference to FIGS.

In FIG. 9A, the finisher 500
Is transported to the buffer roller 513 by the transport rollers 510 and 511, and is discharged to the sample tray 701 by the discharge roller 519 in the non-sort mode. In the case of the sort mode, after a plurality of sheets (for example, three sheets) are accumulated in the buffer path 516 around the buffer roller 513, the sheet is conveyed through the sort path 521 and discharged to the processing tray 630 by the discharge roller 523. The aligned sheet bundle P on the processing tray 630
₀ is discharged to the stack tray 700 by the discharge rollers 610a and 610b after the binding process is performed by the stapler 601 as necessary (FIG. 7B). Sheet bundle P ₀
When the sheet is discharged, the emergence tray 620 protrudes above the stack tray 700 as shown in (a), retreats as shown in (b) during the discharge, and the sheet bundle P ₀ is removed from the stack tray as shown in (c). 700.

In FIG. 10, when a sheet bundle P ₀ bound and bound in a binding process is discharged to a discharge tray 246 by a discharge roller 245, the upper portion thereof is pressed by a pressing lever 249 weight 251 and a projection 249a. It is ejected while being held down. Discharged sheet bundle P ₀
Gradually increases, the stopper 252 moves in the direction of the arrow 2a.
The sheet bundle is moved little by little in the direction, and the sheet bundle is stacked while being shifted as shown in FIG. This allows
The sheet bundle becomes too high, or the discharged sheet bundle
The sheets are properly stacked without moving into the preceding sheet bundle.

Next, the control of the transport speed (discharge speed) of the Z-folded sheet by the transport roller pair 523 as the first discharge means will be described with reference to FIG.

In the figure, a conveying roller pair 523 for conveying (discharging) the Z-folded sheet is driven by a conveying motor (first discharging means driving means) M10.

The transfer speed of the transfer motor M10 will be described. The size of the Z-folded sheet to be discharged is detected by the sheet size detecting means 21 (FIG. 11), the detected sheet size is set to X, the distance from the conveying roller pair 523 to the discharge rollers 610a and 610b is set to A, and the conveying roller pair is set to A. _Assuming that the distance from the rear end of the Z-folded sheet P discharged from the 523 to the rear end of the Z-folded sheet is α, and the distance from the rear end of the Z-folded sheet to the folded portion PM inside the Z-folded sheet is X / 2,
However, the sheet discharging speed of the pair of conveying rollers 523 is controlled by the control device (control means) 20 so that A> (X / 2 + α) is satisfied.

[0063] Accordingly, Z-folding sheets discharged onto the processing tray 630, the folding portion P _M of the inner, 12
As shown in (a), the sheet is stacked on the processing tray 630 while always being located inside the discharge roller 610 (left side in the figure). That is, the inner folded part P _M, FIG. 12 (b)
Without being caught on the discharge roller 610 as shown in FIG.
The Z-folded sheet P can be properly stacked on the processing tray 630.

Even when the speed of the conveying motor M10 is low, that is, when the distance α from the conveying roller pair 523 to the rear end of the Z-folded sheet P is "0", the above-mentioned A is A> X. By arranging the transport roller pair 522 and the discharge roller pair 610 so as to satisfy / 2, the Z-folded sheet P can be properly placed on the processing tray 630.

[0065]

As described above, according to the present invention,
When the transported Z-folded sheet is transported to the first stacking unit, the transport speed of the Z-folded sheet by the first discharge unit is controlled such that A <X / 2 + α. When the Z-folded sheet is discharged to the first stacking unit, the Z-folded sheet can be properly conveyed onto the first stacking unit without the folded portion inside the Z-folded sheet being caught by the second discharging unit.

[Brief description of the drawings]

FIG. 1 is a vertical sectional front view of an image forming apparatus to which the present invention can be applied.

FIG. 2 is a vertical sectional front view of the sheet processing apparatus according to the present invention.

3A and 3B are longitudinal front views of an inserter (sheet feeder), wherein FIG. 3A is a state in which an auxiliary tray is closed, FIG. 3B is a state in which the auxiliary tray is opened, and FIG. CC sectional view taken on the line of FIG.

FIG. 4 is a vertical sectional side view of a processing tray section and a retreat tray section.

FIG. 5 is a plan view of the auxiliary tray.

FIG. 6 is a plan view of a stopper portion of the saddle stitcher.

FIG. 7 is a block diagram relating to control of the image forming apparatus.

FIG. 8 is a plan view showing a display panel of an operation unit of the image forming apparatus.

FIGS. 9A and 9B are operation diagrams showing the flow of sheets in the sheet processing apparatus according to the present invention, wherein FIG. 9A is a diagram of stacking sheets on a processing tray of a finisher, and FIG. 9B is a diagram showing a sheet bundle from a processing tray to a stack tray; FIG. 3C is a view showing the completion of discharge on the stack tray.

FIG. 10 is a view showing a stacking operation of a sheet bundle on a discharge tray of the saddle stitcher.

FIG. 11 is a block diagram relating to control of the sheet processing apparatus of the present invention.

12A is a vertical side view of a processing tray unit and a pair of transport rollers according to an embodiment of the present invention, and FIG. 12B is a vertical side view of a conventional processing tray unit and a pair of transport rollers. .

[Explanation of symbols]

P sheet (Z-folded sheet) PM Inside folded portion of _M sheet M10 Transport motor (first discharging means driving means) 20 Controller (control means) 111 Photosensitive drum (image forming means) 118 Discharge roller (discharge of apparatus main body) Means 133 discharge roller (discharge means of Z-folding unit) 400 folding processing unit 500 finisher 523 transport roller pair (first discharge means) 630 processing tray (first stacking means) 610 discharge roller (second discharge means) 700 Stack tray (second loading means)

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 3F054 AA01 AC01 BA04 BB07 BF09 3F102 AA01 AB01 BA09 FA04 3F108 AA01 AB01 AC03 BA04 BA08 BB17 CC02

Claims (4)

[Claims] 1. A first discharge unit capable of discharging a conveyed Z-folded sheet, a first discharge unit driving unit for driving the first discharge unit, and a driving of the first discharge unit driving unit Control means for controlling the speed; first loading means for loading the sheets discharged by the first discharging means; and second discharging the sheet bundle on the first loading means to the second loading means. Wherein the distance from the first discharging unit to the second discharging unit is A, and the distance from the first discharging unit to the Z-folded sheet immediately before loading on the first loading unit is The discharged Z
Assuming that the distance to the rear end of the folded sheet is α, the length of the Z-folded sheet is X, and the distance from the rear end of the Z-folded sheet to the folded portion inside the Z-folded sheet is X / 2, A sheet processing apparatus, wherein A controls the discharge speed of the first discharge means so that A> (X / 2 + α). 2. The sheet processing apparatus according to claim 1, wherein the Z-folded sheet is discharged face-down to the first stacking unit, and a folded portion inside the Z-folded sheet is located on a lower side. apparatus. 3. A first discharging means capable of discharging a conveyed Z-folded sheet, a first discharging means driving means for driving the first discharging means, and a driving of the first discharging means driving means. Control means for controlling the speed; first loading means for loading the sheets discharged by the first discharging means; and second discharging the sheet bundle on the first loading means to the second loading means. Wherein the distance from the first discharging means to the second discharging means is A, and the length of the Z-folded sheet is Z in the Z-folded sheet immediately before loading on the first loading means. X is a distance from the rear end of the Z-folded sheet to the folded portion inside the Z-folded sheet is X / 2, wherein A satisfies A> X / 2. apparatus. 4. A sheet processing apparatus according to claim 1, further comprising: an image forming unit configured to form an image on the sheet based on the image information; and a folding unit configured to Z-fold the sheet formed by the image forming unit. An image forming apparatus comprising: a discharge unit configured to discharge a Z-folded sheet from the folding processing unit to the sheet processing apparatus.