JP2000118860A - Sheet post-processing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent oblique-folding of a recording sheet bundle, by making a total height of a sheet post-processing device corresponding to an image forming device, and by correcting a skew of the recording sheet bundle so as to accurately abut the recording sheet bundle on a folding part stopper even if the recording sheet bundle obliquely slides on a stack stand downward. SOLUTION: A feed means for feeing saddle-stitched recording sheets S has a pair of feed rollers 62 (621, 622) for feeding the saddle-stitched recording sheets S to a recording sheet positioning means 65 of a fold means 60. When the saddle-stitched recording sheets S enter into between the feed rollers 62, the feed rollers 62 are kept in a halt state so that a front end part of the saddle- stitched recording sheets S abuts on peripheries of the feed rollers 62 to correct a feed skew of the saddle-stitched recording sheets S. Next, after a prescribed time passes, the feed rollers 62 are driven so that the feed skew-corrected saddle-stitched recording sheets S are fed to the recording sheet positioning means 65 of the fold means 60.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention performs post-processing such as binding (stapling) and folding a sheet bundle on which sheets on which images have been formed by an image forming apparatus such as an electrophotographic copying machine, a printer, and a facsimile. The present invention relates to a sheet post-processing apparatus having a function of discharging paper to a paper discharge unit.

[0002]

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

The finisher has a function connected to an image forming apparatus main body such as a copying machine or a printer, and is driven in response to a sequence operation of a copy or print process.

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

[0005] Such finishers have already been disclosed in Japanese Patent Application Laid-Open Nos. 60-142359 and 60-158463.
No. 62-239169 and Japanese Patent Laid-Open No. 62-288.
002, 63-267667, JP-A-2-276
No. 691, JP-A-8-319054, Japanese Patent Publication No. 5-41
No. 991.

The bookbinding apparatus disclosed in Japanese Patent Application Laid-Open No. 60-183449 has a cover feeder, and performs bookbinding finishing operations such as staple binding and folding in two after superimposing a group of copy sheets and a cover. It is.

JP-A-6-72064 and 7-1874
No. 79 and No. 8-192951 are sheet post-processing apparatuses having a saddle stitching function.

[0008]

(1) First Problem When a sheet bundle after the saddle stitching process is conveyed and sent to a predetermined position of a sheet bundle folding means (folding unit) in the next process, the sheet bundle folding means is used. Is set at a steeply inclined angle, the conveyed sheet bundle is slid down along this steeply inclined surface, and abuts against a stopper below in the conveying direction to position the sheet bundle. Skew correction of a sheet bundle.

However, according to this method, in the case of a sheet post-processing apparatus in which a folding section is arranged below the saddle stitching section, the stacking base of the folding section is steeply arranged, so that the sheet post-processing apparatus main body is not provided. The overall height is increased, and a problem occurs in the relative position between the sheet discharge section of the image forming apparatus main body and the sheet receiving section of the sheet post-processing apparatus.

In addition, since the sheet bundle slides down the stacking base of the folded portion arranged at a steep inclination at a high speed, and the leading end of the sheet bundle collides with the lower stopper, a stopper movable in accordance with the sheet size is provided. Problems such as damage, a change in the stop position of the stopper, and damage to the leading end of the sheet occur.

Alternatively, it is conceivable to provide a width aligning means for aligning the folded portion in the width direction orthogonal to the sheet conveying direction, but the structure becomes complicated.

If the stack base is arranged at a gentle inclination to solve the above-mentioned problem, the stack of sheets may slide down due to the slant of the stack base and come to a stop at an angle to the stopper. When the folding unit operates on the sheet bundle stopped at the oblique position, the sheet bundle is obliquely folded.

(2) Second Problem The rear end of the sheet on which an image is formed by the image forming apparatus is brought into contact with a stopper, and the second end near the side edge of the rear end of the sheet.
When the processed sheet bundle is conveyed by the conveying means and discharged onto the paper discharge tray after performing the stapling process at a location or at one location, the sheet bundle is unevenly placed on the paper discharge tray. In particular, in the case of a small-sized sheet bundle, the moving distance of the sheet bundle from the staple processing position to the sheet discharge tray is large, so that the sheet bundle is scattered on the sheet discharge tray, and the alignment of the sheet bundle is deteriorated. .

[0014]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems in the edge stapling and saddle stitching processes, and provides a sheet post-processing apparatus having the following means. is there.

(1) Means for Solving the First Problem A sheet stacking portion capable of stacking a plurality of sheets and a saddle stitching for binding a central portion of the sheets stacked on the sheet stacking portion in a conveying direction. A sheet post-processing apparatus comprising: a stapling unit for processing; a conveying unit that conveys the saddle-stitched sheet bundle; and a sheet bundle folding unit that folds a central portion of the saddle-stitched sheet bundle in two. The conveying means includes a conveying roller pair for conveying the saddle-stitched sheet bundle toward the sheet positioning means of the sheet bundle folding means, and the conveying roller pair is in a stopped state when a sheet enters. The sheet is held, and the leading end of the saddle-stitched sheet is brought into contact with the outer peripheral surface of the conveying roller pair to correct the sheet conveying bend, and after a predetermined time has elapsed, the conveying roller pair is driven. And a sheet post-processing device that conveys the sheet bundle in which the conveyance curl has been corrected and conveys the sheet bundle to a sheet positioning unit of the sheet bundle folding unit.

(2) Means for Solving the Second Problem A sheet stacking section capable of stacking a plurality of sheets, staple means for binding one end of the sheets stacked on the sheet stacking section, and the binding section A sheet post-processing apparatus, comprising: a conveyance discharge unit configured to convey a processed sheet bundle; and a discharge roller pair configured to sandwich the sheet bundle conveyed by the conveyance discharge unit and discharge the sheet bundle to an elevating discharge tray outside the apparatus. The discharge roller pair is held in a stopped state when the bound sheet bundle is discharged, and the leading end portion of the bound sheet bundle is brought into contact with the outer peripheral surface of the discharge roller pair to form the sheet bundle. A sheet post-processing device for correcting a conveyance skew and driving a pair of discharge rollers after a predetermined time has elapsed to convey the sheet bundle and discharge the sheet bundle to the elevating discharge tray (Claim 3). .

[0017]

Next, an embodiment of a sheet post-processing apparatus according to the present invention will be described with reference to the accompanying drawings.

FIG. 1 shows a sheet post-processing apparatus (finisher).
Image forming apparatus A including FS and automatic document feeder DF
FIG.

The illustrated image forming apparatus A includes an image reading unit 1, an image processing unit 2, an image writing unit 3, an image forming unit 4,
A cassette paper feed unit 5, a large capacity paper feed unit (LCT) 6, a fixing device 7, a paper discharge unit 8, and an automatic duplex copy paper feed unit (ADU) 9 are provided.

An automatic document feeder DF is mounted above the image forming apparatus A. A sheet post-processing device (finisher) FS is connected to the left side of the image forming apparatus A in FIG.

The document d placed on the document table of the automatic document feeder DF is conveyed in the direction of the arrow, and one side or both sides of the document are read by the optical system of the image reading section (scanning exposure device) 1. It is read by the CCD image sensor 1A.

The analog signal photoelectrically converted by the CCD image sensor 1A is subjected to analog processing, A / D conversion, shading correction, image compression processing and the like in the image processing section 2, and then sent to the image writing section 3. .

In the image writing section 3, the output light from the semiconductor laser is applied to the photosensitive drum of the image forming section 4 to form a latent image. In the image forming section 4, charging,
Processing such as exposure, development, transfer, separation, and cleaning is performed, and an image is transferred to a recording sheet (recording paper) S conveyed from the cassette paper supply unit 5 or the large capacity paper supply unit 6. The recording paper S carrying the image is fixed by the fixing device 7 and sent from the paper discharge unit 8 to the sheet post-processing device FS. Alternatively, the single-sided image-processed recording sheet S sent to the automatic double-sided copy sheet feeding unit 9 by the conveyance path switching plate 8A is again subjected to double-sided image processing in the image forming unit 4 and then from the sheet discharging unit 8 to the sheet post-processing apparatus FS. Sent in.

The sheet post-processing apparatus FS includes, from the top in the figure, a fixed sheet discharge tray 10, a cover sheet feeding means 40, a shift processing conveyance section (large-capacity discharge conveyance section) 20, an intermediate placing means 30, a stapling means. 50, sheet bundle folding means (folding means) 60
Are arranged in tandem in a substantially vertical direction.

At the upper right of the sheet post-processing apparatus FS in the figure, an entrance conveying section 70 is disposed. On the left side in the figure of the sheet post-processing apparatus FS, an elevating sheet discharge tray 81 for stacking sheets that have undergone edge binding and shift processing, and a fixed sheet discharge tray 82 for stacking sheets that have undergone saddle stitching and folding processing are provided. Are located.

FIG. 2 is a schematic view showing a sheet conveying path of the sheet post-processing apparatus FS, and FIG. 3 is a sectional view showing an upper mechanism of the sheet post-processing apparatus FS.

The sheet post-processing apparatus FS is installed with its position and height adjusted so that the receiving section 71 of the recording sheet S carried out from the image forming apparatus A matches the sheet discharging section 8 of the image forming apparatus A. .

The transport path of the recording paper S connected downstream of the sheet transport of the pair of rollers 72 at the entrance of the receiving section 71 includes an upper first transport path, a middle second transport path, and a lower third transport path. And the switching gate G1,
Depending on the selection of the angle occupied by G2, the recording paper S is fed to one of the transport paths.

(1) First transport path (non-staple, non-sort mode, paper discharge to fixed paper discharge tray 10 at the top of the apparatus) Image-formed recording paper S discharged from image forming apparatus A
Is introduced into the receiving section 71, is conveyed by the entrance roller pair 72, passes through the right passage 73 of the upper first switching gate G1, and is conveyed to the upper conveyance roller pair 74 (the driving roller 74A, The sheet is conveyed while being nipped by the rollers 74B) and the conveying roller pair 75, travels upward, is further nipped by the pair of discharge rollers 76, is discharged onto the fixed sheet discharge tray 10 at the upper part outside the machine, and is sequentially stacked.

In the sheet conveying process, the switching gate G1 is swung by the driving of the solenoid SD1, and the switching gate G1 is moved.
7 is closed and the passage 73 is opened so that the recording paper S can pass through the fixed paper discharge tray 10.

The fixed sheet discharge tray 10 can accommodate a maximum of about 200 sheets of recording paper S, and can be easily taken out from the upper part of the sheet post-processing apparatus FS.

(2) Second transport path (shift processing mode or non-sort mode, paper is discharged to the elevating paper discharge tray 81) When this transport mode is set, the switching gate G1 is turned on when the solenoid SD1 is off. 73 is closed,
The passage 77 is kept open so that the recording paper S can pass through the passage 77.

The image-formed recording paper S discharged from the image forming apparatus A is supplied to a receiving section 71 and an entrance roller pair 72.
, Passes through a passage 77 formed in an open state below the switching gate G1, and is sandwiched by a pair of conveying rollers 78, and is disposed obliquely below the second switching gate G2 which is a second conveying path. After passing through the passage 21, the conveying roller pair 2
2, via a passage 23, between a pair of conveying rollers (a pair of shift rollers) 24, and via a passage 25, via a pair of discharge rollers 26 (an upper roller 26 </ b> A, a lower roller 26 </ b> B), and a lifting / lowering discharge tray 81 outside the machine. Discharged and placed on top. Reference numeral 27 denotes a swinging unit that swings the upper roller 26A so as to be able to press against and separate from the lower roller 26B.

The elevating sheet discharge tray 81 can accommodate a maximum of about 3000 sheets (A4, B5) of recording sheets S.

(3) Third transport path (edge binding processing mode,
The recording paper S, which has been subjected to the image forming process in the image forming apparatus A and sent to the receiving section 71 of the sheet post-processing apparatus FS, is subjected to the entrance roller pair 72, 1 through the passage 77 below the switching gate G1,
8 and transported to the third transport path.

When the recording paper S having a size larger than A4 and B5 is conveyed in the third conveyance path, the solenoid SD2 is driven, and the recording paper S passes through the passage 31A below the switching gate G2. Downstream transport roller pair 32
And conveyed. The recording paper S is transported further downstream by a pair of conveying rollers 34 (a driving roller 34A and a driven roller 34B).
, And is discharged to the space above the intermediate stacker 35 that is inclined. The recording sheet S further comes into contact with the intermediate stacker 35 or the upper surface of the preceding recording sheet S stacked on the intermediate stacker 35, and slides up. After the end of the recording sheet S in the traveling direction is discharged from the conveying roller pair 34, the recording sheet S starts to descend due to its own weight, slides down on the inclined surface of the intermediate stacker 35, and is near the stapling means (binding means) 50. The edge of the recording sheet S comes into contact with the sheet abutting surface of the movable stopper member (hereinafter, referred to as an edge binding stopper) 51 for edge binding, and stops.

In the third conveying path, the switching gate G2 is used to efficiently and continuously convey small-sized recording paper S such as A4 or B5 size to improve copy productivity.
A passage 31B parallel to the passage 31A below and a switching gate G3 are provided.

Solenoid SD for switching gate G2
When both the solenoid SD3 for the switching gate G3 and the switching gate G3 are driven, the leading ends of the switching gates G2 and G3 both swing counterclockwise in the drawing to close the passages 21 and 31A and open the passage 31B.

The leading end of the first sheet of recording paper S sent out from the pair of conveying rollers 78 passes through the passage 31B and comes into contact with the peripheral surface of the pair of conveying rollers 34 in the rotation stopped state and stops.

Next, the energization of the solenoid SD3 is turned off, and the tip of the switching gate G3 swings clockwise,
The passage 31B is closed, and the passage 31A is opened. The leading end of the second recording sheet S sent out from the pair of conveying rollers 78 passes through the passage 31A, abuts against the peripheral surface of the pair of conveying rollers 34 in the rotation stopped state, and stops.

At a predetermined timing, the conveying roller pair 34 is driven to rotate, and the two recording sheets S are nipped and conveyed simultaneously, and are discharged onto the intermediate stacker 35. The third and subsequent sheets are ejected one by one.

Reference numeral 36 denotes a pair of upstream width matching means movably provided on both side surfaces of the intermediate stacker 35. The upstream width aligning means 36 is movable in a direction orthogonal to the recording paper conveyance direction, and is opened wider than the recording paper width when receiving the sheet where the recording paper S is discharged onto the intermediate stacker 35, and slides down on the intermediate stacker 35. Then, when stopping by contacting the edge binding stopper 51, the side edge of the recording sheet S in the width direction is lightly hit to align the width of the recording sheet bundle (width alignment). At this stop position, when a predetermined number of recording sheets S are stacked and aligned on the intermediate stacker 35, a stapling process (stapling process) is performed by the stapling unit 50, and the recording sheet bundle is stapled.

A notch is formed in a part of the sheet stacking surface of the intermediate stacker 35, and the driving pulley 37A
And a plurality of discharge belts 38 wound around the driven pulley 37B
Are rotatably driven. In part of the discharge belt 38,
The discharge claw 38a is formed integrally, and its tip is
An elliptical locus is drawn as shown by a dashed line in the figure. The stapled recording paper bundle is placed on the discharge belt 38 while the trailing end of the recording paper S is held by the discharge claw 38a of the discharge belt 38, and slides on the mounting surface of the intermediate stacker 35 to be inclined. It is pushed upward and advances to the nip position of the discharge roller pair 26. The recording paper bundle nipped by the rotating discharge roller pair 26 is discharged and stacked on the elevating discharge tray 81.

(4) Fourth Conveying Path (Cover Sheet Feeding Mode) The cover sheet feeding means 40 includes a sheet feeding tray 41, a movable bottom plate 42,
A cover placing portion including a push-up lever 43; a pickup roller 44; a feed roller 45;
And cover cover feeding means.

One cover sheet (cover sheet) K fed from the cover sheet feeding means 40 passes through the passage 47 and passes through the nip position between the drive roller 74A of the transport roller pair 74 and the driven roller 74C. , A passage 79, and a pair of conveying rollers 78, and then the conveying roller pair 32 of the third passage, the passage 33,
After reaching the intermediate stacker 35 via the transport roller pair 34.

The transport roller pair 74 is connected to the central drive roller 7.
4A, and two driven rollers 74B and 74C that are in pressure contact with the driving roller 74A. When the driving roller 74A is driven to rotate to the left as shown, the driven roller 74B is rotated to the right to convey the recording paper S conveyed from the passage 73 upward. At the same time, the driven roller 74C also rotates clockwise, and conveys the cover sheet K conveyed from the passage 47 to the lower passage 79. Therefore, the first rotation of the driving roller 74A causes the first rotation.
It is possible to simultaneously transport the recording paper S on the transport path and the cover K on the fourth transport path in the reverse direction.

(5) Fifth Conveying Path (Saddle Stitching Mode) FIG. 4 is a sectional view showing a staple processing section and a two-fold processing section of the sheet post-processing apparatus FS. FIG. 5A shows the staples S at two places at the center near the end face of the recording paper S.
FIG. 5B is a plan view showing an edge binding process of hitting P, and FIG.
FIG. 5C is a plan view showing an edge binding process in which the staples SP are stapled at one location near the corner of the recording paper S. FIG. It is a top view which shows the saddle stitching process which strikes SP.

As shown in FIG. 4, the stapling means 50, the end stapling stopper 51, and the movable stopper member for saddle stitching (hereinafter referred to as the saddle stitching stopper) 53 are formed in the binding portion unit U, and the guide rail R1, Guided by R2, it can be pulled out to the front side of the sheet post-processing device FS.

The stapling means 50 has a two-part structure of an upper mechanism 50A and a lower mechanism 50B, and forms a passage 52 through which the recording paper S can pass.

The stapling means 50 are arranged in two sets in a direction orthogonal to the sheet conveying direction, and can be moved in a direction orthogonal to the sheet conveying direction by driving means (not shown).
The staple means 50 drives the staples SP at two places at the center in the sheet width direction (see FIG. 5A).

The staple means 50 is supported so as to be swingably rotatable, and staples SP at one corner corresponding to the sheet size (see FIG. 5B).

When the saddle stitching mode is set, the end stapling stopper 5 near the stapling position of the stapling means 50 is set.
1 is retracted from the transport path, and at the same time, the saddle stitching stopper 53 downstream thereof is activated to shut off the passage 52.

When the size (length in the transport direction) of the cover sheet K and the recording sheet S is set or detected, the saddle stitching stopper 53 moves to a predetermined position and stops.

After the cover sheet K is placed at a predetermined position on the intermediate stacker 35, the recording sheet S unloaded from the image forming apparatus A
Are sequentially stacked on the upper surface of the cover sheet K placed on the intermediate stacker 35 from the entrance conveyance section 70 of the sheet post-processing apparatus FS through the third conveyance path, and the end of the recording sheet S is It is positioned in contact with 53. Reference numeral 56 denotes downstream width aligning means for regulating the width direction of the recording sheet at the time of saddle stitching. Like the upstream width aligning means 36, each time one recording sheet is carried in, the width width side of the recording sheet is reduced. Hit the edge to align the width.

The upstream width aligning means 36 and the downstream width aligning means 56 selectively perform width alignment driving by setting the edge binding processing or the saddle stitching processing. That is, at the time of the edge binding processing, only the upstream width matching means 36 is driven, and the downstream width matching means 56 is driven.
Does not drive. Thereby, noise reduction and power saving are achieved.

During the saddle stitching process, the upstream width matching means 36 and the downstream width matching means 56 are driven. During the saddle stitching process, the downstream width matching means 56 is
Driven later. As a result, overlapping of the peak power when the drive system is started can be avoided.

Also, during the saddle stitching process, the intermediate stacker 35
The recording paper S that slides down and travels upstream of the stapling means 50 is first width-aligned by the upstream width aligning means 36 to align the sheets, and then passes through the stapling means 50 to perform saddle stitching. The downstream side width aligning means 56 performs width alignment on the recording paper S that advances toward the stopper 53 to align the sheets. Thus, the intermediate stacker 35
The recording paper S and the cover K, which advance on the upper side and are stacked so as to extend from the staple means 50 to the upstream side and the downstream side.
The width of the sheet is accurately aligned over the entire length of the sheet by the upstream width aligning means 36 and the downstream width aligning means 56.

After the final recording paper S is positioned and mounted on the intermediate stacker 35, the sheet bundle composed of the cover K and all pages of the recording paper S is subjected to saddle stapling by the stapling means 50. By this saddle stitching process, the staples SP are driven into the center of the cover K and the recording paper S in the transport direction. The staple SP is driven from the lower mechanism 50B having the staple driving mechanism to the upper mechanism 50A having the staple clinch.

(6) Sixth conveyance path (two-fold processing mode) After the saddle stitching processing, the saddle stitching stopper 53 swings to
2. Open the downstream passage. The sheet bundle including the cover sheet K and the recording sheet S subjected to the saddle stitching process passes through the curved passage 61.

The above-mentioned curved passage 61 is provided with relay guide means. The relay guide means includes a movable guide means 57, a fixed guide plate 58, and a sheet post-processing device F, which are swingably supported in the vicinity of the discharge port of the binding unit U.
The drive roller 611 and the fixed guide plate 612 are fixed to the body of the S.

The recording paper S passing through the passage 61 passes through guide means 63 which comprises a lower guide plate (stack table) 631 and an upper guide plate 632 which are fixed diagonally downward and forms a sheet passage 633.

A conveying roller pair 62 composed of a driving roller 621 connected to a driving source and a driven roller 622 pressed against the driving roller 621 is provided at an intermediate portion of the guide means 63.
(Registration roller pair).

After the saddle stitching process, the leading end of the sheet bundle that has entered the guide means 63 through the passage 61 abuts on the outer peripheral surface or the nip position of the conveying roller pair 62 held in a stopped state, and regulates the leading end. Is performed to correct the skew of the sheet bundle (resist processing).

A sheet passage detection sensor (photo sensor) PS2 is disposed on the upstream side of the conveyance roller pair 62 in the sheet conveyance direction, and detects the passage of the leading end of the sheet bundle. After detecting the passage of the leading end of the sheet bundle by the photosensor PS2, the drive roller 621 is driven to rotate after a predetermined time has elapsed by the timer of the control means 90. Drive roller 6
The sheet bundle nipped between the roller 21 and the driven roller 622 is conveyed on a lower guide plate (stack table) 631 and is moved to a folding portion movable stopper member (hereinafter, referred to as a folding portion stopper) 65 in the leading end of the sheet bundle in the conveyance direction. The parts abut and stop at a predetermined position. The folding section stopper 65 can be moved to a predetermined position by setting or detecting the sheet size and driving means.

A central portion of the stopped sheet bundle in the conveying direction,
That is, the projecting unit 66 is positioned diagonally below the saddle stitching position.
Is installed. A folding roller pair 67 and a two-fold sheet conveying means 68 are provided diagonally above the saddle stitching position.

The folding means 60 includes a projecting unit 66,
It is composed of a pair of folding rollers 67, a sheet folding means 68 and the like.

The movable holding member 66 in response to the folding start signal
2 moves straight along the fixedly arranged guide bar 663, and the protrusion plate 661 fixed to the movable holding member 662.
Project above the sheet mounting surface. Projection plate 66
1 has a thin knife shape, the tip of which has an acute angle.

The tip end of the protruding plate 661 that projects straight and diagonally upward in the figure pushes up the center of the sheet bundle composed of the cover sheet K and the recording sheet S, and the nip portion of the folding roller pair 67 through the sheet bundle. Push and swing to separate.

After the tip of the protruding plate 661 has passed through the nip portion, the protruding plate 661 retreats, and the central portion of the sheet bundle is nipped by the folding roller pair 67 to form a fold. This fold substantially coincides with the position where the staples are driven into the sheet bundle by the saddle stitching process.

The folding roller pair 67 is composed of a pair of left and right pressing means which are substantially symmetrical. One pressing means is
First pressing roller 671 connected to and driven by a driving source
And rotatably support the first pressing roller 671;
An arm 672 that can swing about a support shaft 673, and a first pressing roller 671 that is locked to one end of the arm 672;
Fold of a previous stage comprising a spring 674 for urging the second pressing roller in the direction of the nip position, a second pressing roller 676 driven by being connected to a driving source, a pulley coaxial with the first pressing roller 671, and a second pulling roller. And a conveying belt 677 wound around the pulley of the pressing roller 676. The other paired pressing means has the same configuration and is denoted by the same reference numeral.

The central portion of the sheet bundle having a fold formed by being pressed by the pair of rotating first pressing rollers 671 is conveyed while being sandwiched by a pair of conveying belts 677, and a pair of second pressing rollers 676 is provided. The fold is further firmly attached at this position, and is fed to the two-fold sheet conveying means 68.

The two-folded sheet conveying means 68 comprises a lower conveying belt 681 and an upper conveying belt 682 for pressing and conveying the sheet bundle. The lower transport belt 681 is stretched between a driving roller 683 and a driven roller 685 and is rotatable. The upper transport belt 682 is stretched between a driving roller 684 and a driven roller 686 and is rotatable.

The sheet bundle sent to the two-fold sheet conveying means 68 is divided into a lower conveying belt 681 and an upper conveying belt 682.
, And is conveyed by being pinched between them, and discharged onto a fixed paper discharge tray 82 outside the machine.

FIG. 6 is a schematic diagram showing the transport path of the cover sheet K and the recording sheet S, the saddle stitching of the sheet bundle, and the folding process.
FIG. 7A is a perspective view of a booklet that has been subjected to saddle stitching and half-fold post-processing, and FIG. 7B is a perspective view illustrating a state in which the post-processed booklet is opened on both sides.

The cover K is placed on the sheet feeding tray 41 of the cover sheet feeding means 40 with the first surface (the first page p1 and the eighth page p8) facing upward. The cover sheet K fed from the sheet feeding tray 41 by the sheet feeding means is conveyed through the fourth conveying path and the third conveying path, and is put on the first surface (p1,
It is placed with p8) facing down.

Next, the recording paper S on which the image has been transported out of the image forming apparatus A is placed on the first side (the third page p3 and the sixth page p3).
The sheet is introduced into the sheet post-processing apparatus FS with 6) facing down. The recording paper S is transported from the entrance transport unit 70 to the third transport path, and is placed on the cover K placed on the intermediate stacker 35 with the first surface facing down.

On the intermediate stacker 35, the cover sheet K and the recording sheet S
And the staple means 50 drives the staple SP to perform saddle stitching.

The sheet bundle subjected to the saddle stitching process passes through the fifth transport path, is placed at predetermined positions on the guide plate (stack base) 64 and the lower guide plate 631 (stack base), and stops. At this time, the sheet bundle is such that the recording paper S is on the first side (p3,
p6) on the upper side, and the cover K on the upper side is the first side (p1, p
8) is placed in a state of facing upward.

Next, the two-fold processing is performed by the pushing-up operation of the protruding unit 66 and the driving rotation of the pair of folding rollers 67, and subsequently, the two-fold sheet conveying means 6.
The paper is pinched and conveyed by the printer 8 and discharged onto a fixed paper discharge tray 82 outside the machine.

In the booklet created by the saddle stitching process and the folding process, the first surface (p1, p8) of the cover K faces outward, the second surface (p2, p7) on the back surface, and further on the inside. The first side (p3, p6) of the recording paper S, which is the contents, and the second side (p4, p5) of the recording paper S are arranged inside the first side (p3, p6). Page alignment is possible.

In the operation section of the image forming apparatus A, the booklet creation auto mode is selected and set, and
When the printing is started, the above-described image process is executed by the control unit of the image forming apparatus A, and the recording sheet S carrying the image is subjected to the saddle stitching processing together with the cover K by the sheet post-processing apparatus FS. A folding process is performed, and a booklet is continuously created and discharged.

In the operation section of the sheet post-processing apparatus FS,
Select and set the booklet creation manual mode.
When the cover K and one recording sheet S on which an image is formed are stacked on the sheet 1 and the feeding operation is started, the control unit of the sheet post-processing apparatus FS converts the cover K and the recording sheet S into the sheet post-processing apparatus. By the FS, the saddle stitching process and the half-folding process are performed, and one booklet is created and discharged.

FIG. 8 shows the discharge belt 38 and the discharge roller pair 26 of the intermediate placing means 30 and the driving roller 6 of the folding means 60.
FIG. 3 is a configuration diagram of a drive system that drives a pair of conveying rollers 11, a pair of conveying rollers 62, and an elevating discharge tray 81.

The motor M2 is connected to the timing belts B1, B
The upper drive roller (hereinafter referred to as upper roller) 26A of the discharge roller pair 26 is rotated via the second pulley 28 and the intermediate pulley 28A, and the lower drive roller of the discharge roller pair 26 is driven via the timing belts B3 and B4 and the intermediate pulley 28B. (Hereinafter referred to as lower roller) 26B is rotated. Motor M1
Further, the drive pulley 37A is rotated via the intermediate pulley 28B and the timing belt B5, and the discharge belt 38 is rotated.

The motor M1 drives and rotates the driving pulley 83A through the illustrated gear train, and rotates the wire 84 that winds the driving pulley 83A and the upper driven pulley 83B. The base of the elevating sheet discharge tray 81 is fixed to a part of the wire 84 by a locking member 85.

In the elevating sheet discharge tray 81, the rollers 86A and 86B rotatably supported at the base thereof slide on the rail member 87, and the wire 84 is rotated by the motor M2. It is possible to go up and down.

The motor M9 rotates the intermediate drive roller 624 via a drive transmission system (not shown). The intermediate drive roller 624 is connected to the drive roller 621 via a timing belt.
To rotate. Further, the intermediate drive roller 624 is connected to the drive roller 6 of the relay guide means via another timing belt.
11 is rotated.

FIG. 9 is a plan view of a main part showing a drive system of the binding unit U and the discharge roller pair 26.

In FIG. 9, the motor M1 drives the upper roller 26A and the lower roller 26B of the discharge roller pair 26 to rotate, and also rotates the two discharge belts 38. The motor M4 moves the two upstream width aligning means 36. The motor M5 performs stapling by moving the two stapling means 50 in parallel and rotationally. The motor M6 moves the downstream width aligning means 56. In addition, the edge binding stopper 51
Are driven by a motor (not shown). The saddle stitching stopper 53 is also driven by a motor (not shown).

FIGS. 10A to 10C are cross-sectional views showing a process of discharging a small-size sheet bundle after the edge binding process to the elevating discharge tray 81. FIG.

Here, the small-sized recording paper S is a sheet having a length in the transport direction smaller than a distance L from the sheet abutting front end surface of the end binding stopper 51 to the nip position of the discharge roller pair 26. For example, A4 vertical (297 mm in length in the transport direction), A4 horizontal (210 mm), B5 vertical (182 mm), 11 × 8.5 inch vertical (279 m)
m), a size such as 11 × 8.5 inches wide (216 mm) is referred to as a small-size recording sheet S.

FIG. 10A is a cross-sectional view showing a state in which the stapling process is performed in the vicinity of the rear end side edge of the small-sized recording paper bundle S.

The trailing end of the recording paper bundle S placed on the intermediate stacker 35 is
1A, and the both sides of the recording paper bundle S are pressed by the upstream width aligning means 36 to be width-aligned.
Are stapled. In this state, the leading end of the small-sized recording paper bundle S is located at a position separated from the discharge roller pair 26.

FIG. 10B shows a state in which the stapled recording paper bundle S is rotated by the discharge claw 3 of the discharge belt 38 which has started rotating.
8A is a cross-sectional view illustrating a state in which the recording paper bundle S is sent obliquely upward by 8a and the leading end of the recording paper bundle S is abutted against the outer peripheral surface of the discharge roller pair 26.

In the process of transporting the recording paper bundle S, the upstream width aligning means 36 is retracted from both side surfaces of the recording paper bundle, and the recording paper bundle is pushed out only by the discharge claw 38a, and is pushed onto the surface of the intermediate stacker 35. Are slid and moved, so that skewing easily occurs during the movement.

When the upper edge surface of the leading end portion of the recording paper bundle S is pressed against the outer peripheral surface of the discharge roller pair 26 held in a stopped state, the skew of the transported recording paper bundle is corrected. Is done.

FIG. 10C shows that the skew-corrected recording paper bundle S is conveyed by the discharge roller pair 26 and is moved up and down the discharge tray 8.
FIG. 2 is a cross-sectional view showing a state of being housed in 1.

A large-size recording paper (for example, A3 size vertical (420 mm), 14 × 8.5 inch vertical (356 m
m), 17 × 14 inches (431 mm), etc.) When the S is loaded on the intermediate stacker, the upper roller 26A is oscillated by a motor (not shown) to move away from the nip position with the lower roller 26B. The recording paper bundle S is moved so as to pass through the leading end of the stack of recording papers S. After a predetermined number of recording papers S are stacked, edge binding processing is performed on the recording paper bundle S.

The trailing end of the recording paper bundle S is
The first sheet abuts against the sheet abutting surface 51A, and the leading end is conveyed after being stapled while being held between the pair of discharge rollers 26. Therefore, there is no possibility that the recording paper bundle S skews.

FIG. 11 is a block diagram of the control means 90 for controlling the driving of the discharge roller pair 26 and the transport roller pair 62.

The sheet passage sensor PS1 shown in FIGS. 2 and 3
Detects the length of the recording sheet S in the transport direction, and the control unit 90 determines the sheet size. If it is determined that the sheet size is any of the specific small sizes smaller than the above L, after the stapling process, the discharge belt 38 is moved for a predetermined time (a first set time by the timer 91) corresponding to each sheet size. Drive and stop. At the end of the drive, the leading end of the recording paper bundle S is pressed against the outer peripheral surface or the nip position of the discharge roller pair 26 in the rotation stopped state, the leading end of the recording paper bundle S is aligned, and the skew is corrected. .

Further, after a lapse of a predetermined time (a second set time by the timer 91), the discharge belt 38 is driven again, and the discharge claw 38a pushes up and conveys the rear end portion of the recording paper bundle S, and at the same time, the discharge roller pair 26 Also starts driving, and conveys the recording paper bundle S while nipping it, and discharges it onto the elevating discharge tray 81.

The leading end of the sheet bundle conveyed after the saddle stitching process contacts the outer peripheral surface or the nip position of the conveying roller pair 62 held in a stopped state, and the leading end is regulated.
The skew of the sheet bundle is corrected (resist processing).

A sheet passage detection sensor (photo sensor) PS2 arranged upstream of the folding means 60 in the sheet conveying direction.
After detecting the passage of the leading end of the sheet bundle by the control unit 90, after a lapse of a predetermined period of time measured by the timer 91 of the control unit 90, the driving roller 621 whose rotation has been stopped is driven to rotate, and is conveyed by being pinched with the driven roller 622. It is transported on the plate 64. The leading end of the sheet bundle comes into contact with the folding portion stopper 65 stopped at a predetermined position corresponding to the sheet size.

In the embodiment of the present invention, a sheet post-processing apparatus connected to a copying machine has been described. However, a sheet post-processing apparatus connected to an image forming apparatus such as a printer or a facsimile or a light printing machine or the like is used. Is also applicable.

[0106]

According to the first aspect of the sheet post-processing apparatus of the present invention, the binding processing section and the folding section are formed in a two-stage configuration, and the stack base of the folding section is arranged at a gentle inclination.
It is formed on the entire height corresponding to the image forming apparatus. Further, even if the sheet bundle is skewed and conveyed on the stack table, the skew of the sheet bundle is corrected by the registration operation control for stopping the driving of the conveying roller pair, and the sheet bundle stops accurately by contacting the folding portion stopper. This prevents the sheet bundle from being folded obliquely.

According to the second aspect, after the rear end of the sheet on which the image is formed by the image forming apparatus is abutted against the stopper, and the stapling process is performed at two or one positions near the side edge of the rear end of the sheet. When the processed sheet bundle is conveyed by the conveying means and is discharged onto the discharge tray while being nipped by the discharge rollers, a specific small-size sheet bundle is scattered on the elevating discharge tray, and The alignment is prevented from being reduced.

[Brief description of the drawings]

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

FIG. 2 is a schematic diagram illustrating a sheet conveyance path of a sheet post-processing apparatus.

FIG. 3 is a sectional view showing an upper mechanism of the sheet post-processing apparatus.

FIG. 4 is a sectional view showing a lower mechanism of the sheet post-processing apparatus.

FIG. 5 is a plan view showing a two-point end binding process, a corner end binding process, and a saddle stitching process.

FIG. 6 is a schematic diagram illustrating a conveyance path of a cover sheet and a recording sheet, a saddle stitching of a sheet bundle, and a folding process;

FIG. 7 is a perspective view of a booklet that has been subjected to saddle stitching and half-fold post-processing, and a perspective view illustrating a state in which the post-processed booklet is opened on both sides.

FIG. 8 is a configuration diagram of a drive system of the sheet post-processing apparatus.

FIG. 9 is a main part plan view showing a driving system of a binding unit and a discharge roller pair.

FIG. 10 is a cross-sectional view illustrating a process of discharging a small-sized sheet bundle after the edge binding process to an elevating discharge tray.

FIG. 11 is a block diagram of control means for controlling driving of a discharge roller pair and a conveyance roller pair.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 Fixed paper discharge tray (top tray) 20 Shift processing conveyance part (large capacity paper discharge conveyance part) 26 Discharge roller pair 30 Intermediate placement means 35 Intermediate stacker 36 Width alignment means (upstream width alignment means) 38 Discharge belt 38a Discharge Claws 40 Cover feeding means 50 Stapling means 51 Movable stopper member for end stapling (end stapling stopper) 53 Movable stopper member for saddle stitching (saddle stapling stopper) 55 Saddle stapling stopper unit 56 Width alignment member (Downstream width adjustment means) 57 movable guide means 58 fixed guide plate 60 sheet bundle folding means (folding means) 61 passage 611 drive roller 612 fixed guide plate 62 transport roller pair (register roller pair) 621 drive roller 622 driven roller 623 sheet passage 63 guide means 631 lower Guide plate (stack base) 632 Upper guide plate 64 Guide Plate (stack base, sheet bundle placement member) 65 Folding section movable stopper member (folding section stopper, sheet positioning means) 70 Inlet conveyance section (conveyance means) 81 Elevating paper discharge tray 82 Fixed paper discharge tray 90 Control means FS After sheet Processing device (finisher) K Cover (cover sheet) M1, M2, M4, M5, M6, M9 Motor PS1 Sheet passing sensor PS2 Sheet passing detection sensor (photo sensor) S Recording paper (recording paper bundle) SP Staple needle

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Masaru Otsuka Konica Corporation, 2970 Ishikawa-cho, Hachioji-shi, Tokyo Koji Yoshie 2970 Ishikawacho, Hachioji-shi, Tokyo Konica Corporation F term (reference) 3F108 AA01 AC02 AC03 BA03 CD01 EA09 GA02 GA03 GA04 GB01 GB03 HA02 HA36 HA39 HA44 HA54

Claims (3)

[Claims] 1. A sheet stacking unit capable of stacking a plurality of sheets, a staple unit for a saddle stitching process for stapling a central portion of a sheet stacked on the sheet stacking unit in a conveying direction, and the saddle stitching process. In a sheet post-processing apparatus including a conveying unit that conveys a completed sheet bundle and a sheet bundle folding unit that folds a center portion of the saddle-stitched sheet bundle in two, the conveying unit includes a saddle-stitched processed sheet bundle. A conveying roller pair that conveys the sheet bundle toward the sheet positioning unit of the sheet bundle folding unit; the conveying roller pair is held in a stopped state when the sheet enters, and the saddle stitched sheet The leading end of the sheet bundle is brought into contact with the outer peripheral surface of the pair of conveying rollers to correct the sheet conveyance skew, and after a lapse of a predetermined time, the pair of conveyance rollers is driven to correct the sheet skew. A sheet post-processing apparatus for transporting the sheet bundle to a sheet positioning unit of the sheet bundle folding unit. 2. A sheet passing detection sensor is provided upstream of the pair of conveying rollers in the sheet conveying direction, and driving of the pair of conveying rollers is started after a lapse of a predetermined time after the sensor detects the passage of the leading end of the sheet. The sheet post-processing apparatus according to claim 1, wherein: 3. A sheet stacking section on which a plurality of sheets can be stacked, staple means for binding one end of the sheets stacked on the sheet stacking section, and conveying and discharging means for conveying the sheet bundle after the binding processing. And a discharge roller pair for nipping the sheet bundle conveyed by the conveying and discharging means and discharging the sheet bundle to an elevating discharge tray outside the machine, wherein the discharge roller pair comprises a sheet bundle having undergone the binding process. When is discharged, is held in a stopped state, the leading end of the bound sheet bundle is brought into contact with the outer peripheral surface of the pair of discharge rollers, to correct the transport bending of the sheet bundle, and after a predetermined time, A sheet post-processing apparatus for driving the discharge roller pair to convey the sheet bundle and discharging the sheet bundle to the elevating sheet discharge tray.