JP2003341912A - Sheet post-treating device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sheet post-treating device capable of enhancing the aligning performance of sheets of paper on a sheet placing table, the accuracy in the punching process and stapling process, and the producibility, etc., of sheet placing. <P>SOLUTION: The sheet post-treating device includes a sheet head restricting member 64 which is installed downstream in the sheet carrying direction of an inlet roller 61, arranged movable in compliance with the size of paper sheets S to be fed, and is capable of moving between two positions, a first position in which the rear end of the sheet S held by a gripper 62 passes the pinching position of the inlet roller 61 and then the head of the sheet runs against the member 64 so as to allow the sheet S to be dropped onto the sheet placing table 63 and a second position in which the head of the sheet S placed on the table 63 is pressed and the rear end of the sheet is put in pressure contact with a sheet abutting part 67 so as to make alignment in the sheet carrying direction. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic copying machine,
For sheets ejected from image forming apparatuses such as printers, facsimiles, and multifunction machines having these functions,
The present invention relates to a sheet post-processing device that performs post-processing such as punching processing, binding processing, and folding processing.

[0002]

2. Description of the Related Art A large number of sheets on which an image is recorded by a main body of an image forming apparatus such as a copying machine, a printer, a facsimile, and a complex machine of these are gathered for each number of prints and bound by a binding means (stapler). A sheet post-processing device for binding together is provided. The sheet post-processing device is connected to and driven by the print function of the main body of the image forming apparatus.

As a sheet post-processing device for binding a bundle of a plurality of sheets as a set, Japanese Patent Laid-Open No. 2-276
691, No. 8-319054, Japanese Examined Patent Publication No. 5-4199
No. 1 publications and the like are disclosed.

[0004]

The conventional sheet post-processing apparatus has the following problems.

In the conventional sheet post-processing apparatus, when the front end of the sheet is gripped and conveyed by the gripper to be placed on the sheet mounting table, first, the gripper at the standby position is reversely driven by the driving means to convey the sheet. By retracting the paper by a predetermined amount in the direction opposite to the direction, moving again in the paper transport direction, and moving the paper gripped by the gripper onto the paper loading table,
The paper grip was released at a predetermined position, and the paper was placed on the paper table.

When a sheet discharged from the image forming apparatus is nipped by an inlet roller, then the sheet is gripped by a rotating gripper and conveyed on a sheet mounting table of a punching section or a binding section, a conventional sheet is used. The post-processing device has the following problems.

The conveyance of the sheet on the sheet mounting table is unstable, the consistency of the sheet on the sheet mounting table is insufficient, and the accuracy of the punching process and the binding process is reduced. It takes a long time to place it in a position and productivity is poor. In particular, high-speed post-processing in a paper post-processing device connected to the high-speed image forming apparatus is desired.

[0008]

The above problems can be solved by the following sheet post-processing device of the present invention.

An entrance roller for carrying in the paper discharged from the image forming apparatus, and a rotatable holder for holding the leading end of the paper discharged from the entrance roller and carrying it in the carrying direction at the same linear speed as the paper carrying linear speed. A gripper, a paper loading table for accommodating and stacking the paper held and conveyed by the gripper, and arranged on the downstream side of the entrance roller in the paper conveyance direction,
A sheet leading edge regulating member that is movable according to the size of a sheet to be carried in; and a binding unit that performs binding processing on the sheet that has been aligned in the sheet conveying direction by the sheet leading edge regulating member. The leading edge regulating member enables the sheet held by the gripper to fall on the sheet loading table after the trailing edge of the sheet has passed the nipping position of the entrance roller and the trailing edge of the sheet hits the leading edge regulating member. The first position to
It is possible to move between a second position for pressing the front end of the paper placed on the paper placing table and pressing the rear end of the paper against the paper abutting portion to align the paper conveyance direction. Paper post-processing device.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS [Image Forming System] FIG. 1 is an overall configuration diagram of an image forming system including an image forming apparatus A and a sheet post-processing apparatus (hereinafter referred to as a post-processing apparatus) B.
FIG. 2 is an external perspective view of the image forming system.

[Image Forming Apparatus] In the image forming apparatus A, a charging device 2 and an image exposing device (image writing section) 3 are provided around a rotating electrostatic latent image carrier (hereinafter referred to as an image carrier) 1. , A developing device 4, a transfer device 5A, a charge eliminating device 5B, and a cleaning device 6 are arranged. The image forming unit
After the surface of the image carrier 1 is uniformly charged by the charging device 2, the latent image is formed by performing exposure scanning based on the image data read from the original by the laser beam of the image exposure device 3 to form a latent image. Is subjected to reversal development by the developing device 4 to form a toner image on the surface of the image carrier 1.

On the other hand, the sheet feeding cassettes 7A and 7B arranged in the middle stage of the image forming apparatus A, the large-capacity sheet feeding trays 7C and 7D arranged in the lower stage, and the manual sheet feeding tray 7E arranged sideways are supplied. The recording sheet S that has been printed is registered by the registration roller 7
It is sent to the transfer position via F.

At the transfer position, the transfer device 5A transfers the toner image onto the recording sheet S. After that, the recording paper S is separated from the image carrier 1 by removing the electric charge on the back surface by the static eliminator 5B, transported by the reversal transport unit 9C, subsequently heated and fixed by the fixing device 8 and discharged by the discharge roller 9A. It

When images are to be formed on both sides of the recording paper S, the recording paper S heated and fixed by the fixing device 8 is branched from the normal paper discharge path by the transport path switching plate 9B.
After being switched back and turned upside down in the reversing / conveying unit 9C, it passes through the image forming unit again, forms an image on the back surface of the recording sheet S, passes through the fixing device 8, and is ejected outside the device by the paper ejection roller 9A. .

On the other hand, the surface of the image carrier 1 after image processing is
The cleaning device 6 removes the developer remaining on the surface to prepare for the next image formation.

[Post-Processing Device] FIG. 3 is an overall configuration diagram of the post-processing device B according to the present invention.

The post-processing apparatus B includes a receiving unit 10, a direct paper discharging unit 20, a cover paper feeding unit 30, a punching processing unit 40, a paper folding processing unit 50, a binding processing unit 60, a paper stack folding unit 70, and a paper discharging unit. It is composed of a section 80.

Receiving Portion 10 The inlet 11 of the receiving portion 10 is installed at a position and height that coincide with the paper discharge roller 9A of the image forming apparatus A.

Into the receiving section 10, the recording sheet S subjected to the image forming processing from the image forming apparatus A and the cover sheet K supplied from the cover sheet feeding section 30 are introduced.

The recording sheet S introduced into the entrance 11 is directly discharged by the conveying path switching means G1 into the sheet discharge section 20 and the punching section 4.
It branches to either 0.

Direct Paper Discharging Section 20 When this paper transportation is set, the transportation path switching means G1 shuts off the transportation path to the punching processing section 40 and opens the transportation path directly to the paper discharging section 20.

The recording sheet S that directly passes through the conveying path of the sheet discharging section 20 is nipped by the conveying rollers 21, rises, is discharged by the sheet discharging rollers 22, and is placed on the fixed sheet discharging table 23.
It is loaded in sequence. A maximum of about 200 recording sheets S can be stacked on the fixed sheet discharge table 23.

Cover sheet feeding section 30 cover sheet K accommodated in the feed tray of cover sheet feeding section 30
Are separated and fed by the sheet feeding means 31, and the transport roller 3
It is sandwiched by 2, 33 and 34 and introduced into the receiving unit 10. Hereinafter, the recording sheet S and the cover sheet K will be collectively referred to as the sheet S.
Collectively.

Punch processing section 40 The sheet S branched by the transport path switching means G1 of the receiving section 10 is the punch processing section 4 arranged at the uppermost stage of the post-processing apparatus B.
Transported to 0. The paper S passes through the entrance roller 41,
The gripper 42 moves at the same linear velocity as the linear velocity of the outer peripheral surface of the entrance roller 41, and the gripper 42 advances.

When the trailing edge of the sheet S passes through the nipping position of the entrance roller 41, the trailing edge of the sheet S becomes free and falls onto the sheet loading table 43. After that, the leading edge of the sheet S held by the moving gripper 42 is moved to the sheet leading edge regulating member 4
By hitting the sheet 4, the gripper 42 releases the holding of the leading edge of the sheet S. The leading edge of the sheet S whose holding of the leading edge has been released falls by its own weight, and the inclined sheet placement table 43 is placed.
Move down quickly.

The paper S placed on the paper table 43 is
It is pressed by the sheet leading edge regulating member 44 and comes into contact with the sheet abutting portion 47 of the punch 46 and stops. In the alignment process in the paper transport direction, the paper width alignment means 45 positions the paper S in the width direction. Subsequently, the perforator 46 punches a file hole h near the leading edge of the sheet S.

The punch 46 is composed of a punch which is driven up and down by a driving means, and a die which is fitted to the blade of the punch.

The rear end of the perforated sheet S is pressed by the sheet ejection claw 48A fixed to the rotating sheet ejection belt 48 to move on the sheet mounting table 43 in the leftward direction in the figure, and the sheet ejection roller is ejected. The sheet is sandwiched by 81 and placed on an elevating and discharging tray 82. Alternatively, the paper S branched by the transport path switching unit G2 is subjected to post-processing such as binding and folding.

The punching unit 40 can also perform a shift process for moving the paper S in the paper width direction.

FIG. 4 (a) is a perspective view of the sheet S punched by the punch 46. The sheet S on which the intermediate conveyance path binding processing and the folding processing are performed is downwardly changed in direction by the conveyance path switching unit G2, and further moved rightward in the figure by the plurality of conveyance rollers R1, R2, and R3.
The transport path switching unit G3 switches the sheet S to one of the transport paths of the sheet folding processing unit 50 and the binding processing unit 60.

Paper folding processing unit 50 A plurality of folding rollers 5 are provided for the paper S that has advanced to the paper folding processing unit 50 through the transportation path above the transportation path switching means G3.
Various folding processes are performed by 1, 52, 53, 54.

The folded sheet S is bound by the binding processing section 60.
The sheet is conveyed onto the sheet mounting table 63 inside, is pressed by the sheet discharging claw 68A fixed to the rotating sheet discharging belt 68, moves on the sheet mounting table 63 in the left direction in the drawing, and is nipped by the sheet discharging roller 83. And is placed on the elevating and ejecting table 82.

FIG. 4B is a perspective view of the sheet S that has undergone center folding processing, FIG. 4C shows a perspective view of the sheet S that has undergone Z folding processing, and FIG. It is a perspective view of the processed paper S.

Stitching Processing Unit 60 The binding processing unit 60 stacks and aligns the sheets S and performs side stitching processing or saddle stitching processing.

FIG. 4E shows a sheet bundle S subjected to the side stitching process.
FIG. 4 (f) is a perspective view of a sheet bundle S subjected to saddle stitching processing.
It is a perspective view of a.

.. The paper S that has passed through the transport path below the side stitching processing transport path switching means G3 and has proceeded to the binding processing section 60 is transport rollers R4, R5, R
6, R7, passes through the inlet roller 61, is held by the gripper 62 which moves at the same linear velocity as the linear velocity of the outer peripheral surface of the inlet roller 61, and advances.

When the trailing edge of the sheet S passes through the nipping position of the entrance roller 61, the trailing edge of the sheet S becomes free and falls on the sheet loading table 63. After that, the leading edge of the sheet S held by the moving gripper 62 is moved to the sheet leading edge regulating member 6
By hitting the sheet 4, the gripper 62 releases the holding of the leading edge of the sheet S. The leading edge of the sheet S whose holding of the leading edge has been released falls by its own weight, and the inclined sheet placement table 63 is placed.
Move down quickly.

The sheet S placed on the sheet table 63 is
It is pressed by the sheet leading edge regulating member 64 and comes into contact with the sheet abutting portion 67 of the side stitcher (side stitching means) 66A for side stitching and stops. In the alignment process in the paper transport direction, the paper width alignment means 65 positions the paper S in the width direction.

Every time a plurality of succeeding sheets S are sequentially loaded on the sheet mounting table 63 and carried in, the alignment in the sheet transport direction and the alignment in the sheet width direction are performed. When the stacking of the predetermined number of sheets is completed, the stapler 66A staples the binding needle SP near the leading end of the sheet S to form the sheet bundle Sa (see FIG. 4E).

The rear end portion of the side-stitched sheet bundle Sa is
It is pressed by the paper ejection claw 68A fixed to the rotating paper ejection belt 68 to move leftward in the drawing on the paper placing table 63, and is pinched by the paper ejection rollers 83 and placed on the elevating paper ejection table 82. It

.. Saddle stitching processing A saddle stitching device (saddle stitching means) 66B for saddle stitching is constituted by a two-part structure of a lower stapling mechanism 66B1 and an upper stapling mechanism 66B2, and a sheet S is placed in the middle thereof. It forms a paper passage that can pass through.

When the saddle stitching process is designated, the sheet leading edge regulating member 64 moves to a predetermined position in the downstream direction of sheet conveyance corresponding to the sheet size and stops.

The sheet S having proceeded to the binding processing section 60 passes through the transport rollers R4, R5, R6, R7 and the entrance roller 61, and is transferred to the gripper 62 which moves at the same linear speed as the linear speed of the outer peripheral surface of the entrance roller 61. It is pinched and progresses.

When the trailing edge of the sheet S passes through the nipping position of the entrance roller 61, the trailing edge of the sheet S falls on the sheet mounting table 63. Then, the leading edge of the sheet S held by the moving gripper 62 hits the sheet leading edge regulating member 64, and the gripper 62 releases the holding of the leading edge of the sheet S. The leading edge of the sheet S whose holding of the leading edge is released falls by its own weight, and quickly descends on the inclined sheet placing table 63.

The paper S placed on the paper table 63 is
It slides down on the inclined sheet placing table 63, contacts the sheet abutting portion 67, and stops. At the stop position of the sheet S, the sheet width aligning unit 65 positions the sheet S in the width direction.

A plurality of succeeding sheets S are successively stacked on the sheet mounting table 63, each time the sheet S is carried in, alignment in the sheet conveying direction and
When the width alignment is performed and the stacking of the predetermined number of sheets is completed, the stapler SP staples the staple SP at the central portion of the sheet S to form the sheet bundle Sa (see FIG. 4F).

The rear end of the saddle stitched sheet bundle Sa is
It is pressed by the paper ejection claw 68A fixed to the rotating paper ejection belt 68 to move to the left in the drawing on the paper placement table 63, and advances along the conveyance path below the conveyance path switching means G4 to form the sheet bundle folding section. It is conveyed to 70.

Sheet bundle folding section 70 In the sheet bundle folding section 70, the saddle-stitched sheet bundle Sa is subjected to center folding processing by a pair of folding rollers 71 and a folding knife 72.

FIG. 4G is a perspective view of the sheet bundle Sa that has undergone post-processing of saddle stitching and center folding. The center-folded sheet bundle Sa has its folds reinforced by the reinforced folding means 73. The sheet bundle Sa that has undergone the center folding process is ejected to the outside of the machine by the sheet ejection belt 84.

[Sheet Leading Edge Regulation Member] Side-Binding Processing FIG. 5 is a sectional view showing details of the side-binding processing in the binding processing section 60.

Drive pulley 6 connected to a drive source (not shown)
The rotation of the drive pulley 622 and the driven pulley 62
The belt 621 that winds around 3 rotates. The flat portion of the belt 621 is arranged in parallel with the flat portion of the paper tray 63. Further, the linear velocity when the belt 621 rotates is set to be equal to the linear velocity of the entrance roller 61.

The base of the gripper 62 is fixed to a part of the belt 621. The leading end of the gripper 62 holds the leading end of the sheet S nipped by the entrance roller 61 and is conveyed, and conveys it.

Drive pulley 6 connected to a drive source (not shown)
By the rotation of 42, the drive pulley 642 and the driven pulley 64
The belt 641 that winds around 3 rotates. The flat portion of the belt 641 is arranged in parallel with the flat portion of the sheet mounting table 63. A sheet leading edge regulating member 64 is fixed to a part of the belt 641.

When the sheet size and the side-stitching process are designated in the operation section of the image forming apparatus A, the belt 641 is rotated by a drive source (not shown), and the sheet leading edge regulating member 64 is at a predetermined stop position corresponding to the sheet size. Go to and stop.

At the stop position of the sheet leading edge regulating member 64, the leading edge of the sheet S held by the gripper 62 is set after the trailing edge of the sheet S has passed the nipping position of the entrance roller 61 and can fall by its own weight. Abutting on the leading edge regulating member 64,
The first position is where the paper S can be dropped from the gripper 62 by its own weight.

A flexible sheet trailing end pressing plate (elastic member) 69 is arranged on the downstream side of the entrance roller 61 in the sheet conveying direction. The paper rear end pressing plate 69 is made of polyethylene.
It is formed of a thin film plate made of a resin material such as terephthalate (PET).

The base of the sheet trailing edge pressing plate 69 is a post-processing device B.
It is cantilevered on the fixed part. The front end portion of the paper trailing edge pressing plate 69 becomes a free end, and the upper surface side of the paper S conveyed by the entrance roller 61 and the gripper 62 is lightly pressure-contacted.

The sheet trailing edge pressing plate 69 urges the trailing edge of the sheet S by lightly pressing it after the trailing edge of the sheet S has passed the holding position of the entrance roller 61 and is allowed to fall by its own weight. , Is quickly moved to the paper table 63.

By biasing the rear end of the sheet S by the sheet rear end pressing plate 69 and forcibly dropping it, the rear end of the sheet S is prevented from staying on the entrance roller 61. In addition, since it is possible to shorten the time required for the sheet S to drop onto the sheet mounting table 63, the productivity of the side-stitching process is improved.

When the leading edge of the sheet S held by the moving gripper 62 hits the sheet leading edge regulating member 64, the gripper 62 releases the holding of the leading edge of the sheet S. The leading edge of the sheet S whose holding of the leading edge is released falls by its own weight, and quickly descends on the inclined sheet placing table 63.

The sheet S falling on the sheet placing table 63 and sliding down is pushed on the sheet placing table 63 which is installed in a slanted state because the leading edge of the sheet S in the sheet conveying direction is pressed by the movement of the sheet leading edge regulating member 64. Down. The sheet width aligning means 65 aligns in the sheet width direction.

When the front end of the paper is pressed by the movement of the front end restricting member 64, the rear end of the paper comes into contact with the paper abutting portion 67 and stops at the second position of the front end restricting member 64. Be aligned.

The succeeding paper S is similarly subjected to the entrance roller 61.
The sheet is conveyed from the sheet stacker, is stacked on the sheet mounting table 63, and the sheet width direction alignment and the trailing edge portion alignment are performed.

After all the sheets S ejected from the image forming apparatus A have been aligned in the sheet width direction and the rear edge portion in the binding processing section 60 of the post-processing apparatus B, they are side-stitched by the side stitcher 66A. The processing is performed, and the binding staple SP is stapled on the sheet bundle Sa (see FIG. 4E). PA indicates the side stitching position.

The rear end of the side-stitched sheet bundle Sa is
The sheet is ejected from the binding processing unit 60 by being pressed by the sheet ejection claw 68A fixed to the rotating sheet ejection belt 68 to move on the sheet mounting table 63 in the left direction in the drawing.

Two sets of the side stitchers 66A are arranged in the sheet width direction orthogonal to the sheet conveying direction, and can be moved to a predetermined position in the sheet width direction by a driving means (not shown). The side stitcher 66A can perform side stitching processing on a maximum of 100 sheets of paper S.

Saddle Stitching Processing FIG. 6 is a sectional view showing details of the saddle stitching processing in the binding processing section 60.

A saddle stitcher 66B is arranged near the center of the sheet mounting table 63 in the sheet conveying direction. Saddle stitcher 6
6B is a lower stapling mechanism 66B1 and an upper stapling mechanism 66B.
It is configured in a two-division structure with B2, and a paper passage through which the paper S can pass is formed in the middle thereof.

The stapling mechanism 66B1 accommodates the staple SP and strikes the staple SP from the lower surface side of the sheet bundle Sa. The staple receiving mechanism 66B2 is provided with a staple S that is driven into the sheet bundle Sa.
Press the tip of P to fold it (clinch), stack of sheets S
Saddle-stitch processing a.

The needle receiving mechanism 66B2 comprises a fixed portion 661 and a movable portion 662. The movable portion 662 can slide up and down on the guide member 663. Movable part 66 shown by the solid line in the figure
Reference numeral 2 is an upper limit position that allows the sheet bundle Sa to easily pass when the maximum 100 sheets S are side-stitched and discharged. The movable portion 662 indicated by a broken line in the figure is a lower limit position that allows the sheet bundle Sa to easily pass when the maximum 50 sheets S are saddle-stitched and discharged.

The fixing portion 661 is slidably supported by two guide members 664 fixed to the fixing member of the post-processing apparatus B, and is movable in the paper width direction perpendicular to the paper surface.

The needle striking mechanism 66B1 is also movable by sliding on the guide member 665. The stapling mechanism 66B1 is a post-processing device B.
It is slidably supported by two guide members 665 fixed to the fixed member and is movable in the paper width direction perpendicular to the paper surface.

Two sets of the saddle stitcher 66B are arranged in the paper width direction orthogonal to the paper transport direction, and can be moved to a predetermined position corresponding to the paper size by a driving means (not shown).

The fixing portion 661 and the stapling mechanism 66B1 are moved to a predetermined stop position corresponding to the paper size and stopped by a driving means (not shown).

When the paper size and the saddle stitching process are designated in the operation section of the image forming apparatus A, the belt 641 is rotated by a driving source (not shown), and the paper leading edge regulating member 64 is at a predetermined stop position corresponding to the paper size. Move to (near the left end in the figure) and stop.

At the stop position of the sheet leading edge regulating member 64, the leading edge of the sheet S held by the gripper 62 is set after the trailing edge of the sheet S has passed the nipping position of the entrance roller 61 and can fall by its own weight. Abutting on the leading edge regulating member 64,
It is a position where the sheet S can be dropped from the gripper 62 by its own weight.

The trailing edge of the sheet S of the sheet trailing edge pressing plate 69 disposed near the inlet roller 61 has the trailing edge of the sheet S at the inlet roller 61.
After passing through the nip position of the
The rear end of the sheet is lightly pressed and urged, and is quickly moved to the sheet mounting table 63.

By biasing the rear end of the sheet S by the sheet rear end pressing plate 69 and forcibly dropping it, the rear end of the sheet S is prevented from staying on the entrance roller 61. In addition, since it is possible to shorten the time required for the sheet S to drop onto the sheet mounting table 63, the productivity of the saddle stitching process is improved.

The sheet S dropped on the sheet placing table 63 is pushed down by the sheet leading edge regulating member 64 at the leading end of the sheet S in the sheet conveying direction, and descends on the inclined sheet placing table 63. The trailing edge of the sheet abuts against the sheet abutting portion 67 near the stapler 66A and stops, and the trailing edge of the sheet is aligned. After the rear end of the sheet is aligned, the sheet width aligning unit 65 aligns the sheet in the sheet width direction. The sheet width aligning means 65 is arranged substantially in the middle of the side stitching device 66A and the saddle stitching device 66B, and can perform sheet width aligning during the side stitching process and sheet width aligning during the saddle stitching process.

The succeeding paper S is similarly subjected to the entrance roller 61.
The sheet is conveyed from the sheet stacker, is stacked on the sheet mounting table 63, and the sheet rear end alignment and the sheet width alignment are performed.

After all the sheets S discharged from the image forming apparatus A have been aligned in the sheet width direction and the rear end portion in the binding processing section 60 of the post-processing apparatus B, the sheet discharge belt 68 is rotated. Is started. The paper discharge claw 68A fixed to the paper discharge belt 68 supports the rear end portion of the paper stack Sa positioned and stacked on the paper mounting table 63 and conveys the paper stack Sa,
Stop at a predetermined position corresponding to the paper size.

Sheet bundle Sa stopped at a predetermined saddle stitch position
Saddle-stitching processing is performed by the saddle-stitcher 66B at the central portion in the transport direction of, and the stapling needle SP is stapled on the sheet bundle Sa (FIG. 4).
(See (f)). PB indicates the saddle stitching stapling position.

The stop position of the paper discharge belt 68 by the paper discharge claw 68A during the saddle stitching process is set to a predetermined position depending on the paper size.

The rear end of the saddle-stitched sheet bundle Sa is
The sheet is ejected from the binding processing unit 60 by being pressed by the sheet ejection claw 68A fixed to the rotating sheet ejection belt 68 to move on the sheet mounting table 63 in the left direction in the drawing.

The sheet leading edge regulating member 44 arranged in the perforation processing section 40 and the sheet leading edge regulating member 64 arranged in the binding processing section 60 have substantially the same structure, and the gripper 42,
The gripping of 62, the contact of the leading edge of the sheet, and the alignment of the trailing edge of the sheet are performed.

[0086]

As is apparent from the above description, the paper post-processing apparatus of the present invention has the following effects.

The sheet leading edge regulating member hits the sheet leading edge regulating member after the sheet held by the gripper has passed the nipping position of the inlet roller by the trailing edge of the sheet.
Alignment in the paper transport direction with the first position that allows the paper to drop by its own weight on the paper tray and the leading edge of the paper placed on the paper tray to press the trailing edge of the paper against the paper abutting portion By the sheet post-processing device that makes it possible to move the second position and
It is possible to suppress the unstable behavior of the sheet while falling by its own weight on the sheet placing table and to stably place the sheet.

The consistency of the sheets on the sheet mounting table is ensured, and the precision of the punching process and the binding process is improved.

The time required for placing the sheet at a predetermined position on the sheet platform is short, and the productivity is improved. In particular, it is effective for improving the productivity of high-speed post-processing in the paper post-processing device connected to the high-speed image forming apparatus.

[Brief description of drawings]

FIG. 1 is an overall configuration diagram of an image forming system including an image forming apparatus and a sheet post-processing apparatus.

FIG. 2 is an external perspective view of the image forming system.

FIG. 3 is an overall configuration diagram of a sheet post-processing apparatus according to the present invention.

FIG. 4 is a punched sheet, a center-folded sheet,
Z-folded paper, inward three-fold paper,
FIG. 3 is a perspective view of a sheet bundle subjected to side stitching processing, a sheet bundle subjected to saddle stitching processing, and a sheet bundle subjected to post-processing of saddle stitching and center folding.

FIG. 5 is a cross-sectional view showing the details of flat stitching processing in a binding processing unit.

FIG. 6 is a cross-sectional view showing details of saddle stitching processing in a binding processing unit.

[Explanation of symbols]

40 Punching unit 43, 63 Paper loading table 44,64 Paper edge regulating member 47,67 Paper hitting section 60 binding section 61 Inlet roller 62 gripper 65 Paper width matching means 66A Side stitcher (side stitching means) 66B Saddle stitcher (saddle stitching means) 68 Paper ejection belt 68A Paper ejection claw 641 belt 661 Fixed part 662 Moving part 69 Paper trailing edge pressing plate (elastic member) B Paper post-processing device (post-processing device)

   ─────────────────────────────────────────────────── ─── Continued front page    F term (reference) 2H072 FB08 FB10 GA01 GA08                 3F054 AA01 AC02 AC03 AC05 BA04                       BE04 BG11 BH07 DA01                 3F106 CA05 CA23 LA06 LB03                 3F108 GA02 GA03 GA04 GB01 HA02                       HA39

Claims (3)

[Claims] 1. An entrance roller for carrying in a paper discharged from an image forming apparatus, and a carrier for holding the leading edge of the paper discharged from the entrance roller and carrying it in the carrying direction at the same linear speed as the paper carrying linear speed. A movable gripper, a paper placing table for accommodating and loading sheets to be held and conveyed by the gripper, and a downstream side of the entrance roller in the sheet conveyance direction, which corresponds to the size of the sheet to be conveyed. A movable sheet leading edge regulating member and binding means for binding the sheet that has been aligned in the sheet conveying direction by the sheet leading edge regulating member are held by the gripper. A first position at which the leading edge of the sheet abuts against the sheet leading edge regulating member after the trailing edge of the sheet passes through the nipping position of the entrance roller and falls onto the sheet loading table; and the sheet loading table. Up And a second position for pressing the front end of the paper placed on the paper to press the rear end of the paper against the paper abutting portion for alignment in the paper transport direction, and a post-processing for paper. apparatus. 2. The sheet leading edge regulating member is moved from the first position to reach the second position, and then is driven forward and backward in the sheet conveying direction to press the sheet leading edge portion to move the sheet trailing edge portion. The sheet post-processing apparatus according to claim 1, wherein the sheet abutting portion is pressed against the sheet to align the sheet in the sheet conveying direction. 3. When the leading edge of the sheet held by the gripper comes into contact with the sheet leading edge regulating member, the sheet leading edge regulating member releases the holding of the sheet leading edge of the gripper and allows the sheet to drop by its own weight. The sheet post-processing apparatus according to claim 1, wherein: