JP2003171057A - Sheet subsequent treatment device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve the quality of the external appearance of a sheet bundle after binding by improving alignment performance of sheets in the advancing direction when the sheets slantly disposed on a paper mount are lowered by the dead weight of the sheets and abutted on the abutment member for positioning the tips of the sheets in the advancing direction. <P>SOLUTION: This subsequent treatment device stacks the sheets S discharged from an image forming device on a stack part 30 and binds them. This sheet subsequent treatment device is provided with width alignment means 36 aligning the sheet width direction orthogonally crossing with the carrier direction of the sheets S loaded on the stack part 30 and vertical alignment means 70 aligning the carrier direction of the sheets S loaded on the stack part 30. <P>COPYRIGHT: (C)2003,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,
Sheets ejected after image formation from an image forming apparatus such as a printer, a facsimile, and a multi-function peripheral having these functions are sequentially taken into a sheet post-processing apparatus, and post-processing such as binding processing is performed on the sheets and the sheet is ejected. The present invention relates to a sheet post-processing device having a function of discharging to a sheet.

[0002]

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

This paper post-processing apparatus is connected in function to the main body of an image forming apparatus such as a copying machine or a printer, and is driven in response to a sequence operation of a copying or printing process.

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

Regarding such a sheet post-processing apparatus, JP-A-60-142359 and JP-A-60-15846 have already been proposed.
No. 3, 62-239169, and JP-A-62-28.
8002, 63-267667, JP-A-2-27
6691, JP-A-8-319054, JP-B-5-4
It is disclosed in each publication of 1991.

The bookbinding apparatus disclosed in Japanese Patent Application Laid-Open No. 60-183459 has a cover feeding device and performs bookbinding finishing such as punching or stapling after superposing a copy sheet group and a cover sheet. .

[0007]

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

(1) The sheet discharged from the image forming apparatus is conveyed and introduced into the stacking section, and the sheet is placed on the sheet placing table which is inclined and lowered by the weight of the sheet. When the sheet is brought into contact with the abutting member that positions the sheet, the leading end of the falling sheet hits the abutting member and bounces back, causing unevenness of the leading end of the sheet. If the binding process is performed with this irregularity, the appearance quality of the sheet bundle deteriorates.

(2) When the stapled sheet bundle is held and moved by the discharge claws fixed to the rotating discharge belt to be discharged, when the discharge claws are retracted from the sheet bundle conveying path, the discharge is performed. The claws interfere with the rear end portion of the sheet bundle in the traveling direction, causing damage to the sheet bundle, and deteriorating the finished appearance quality of the sheet bundle.

(3) When the sheet discharged from the image forming apparatus is accommodated in the stacking section by the transporting means, the sheet is dropped on the sheet mounting table inclined in the stacking section, and the sheet below the sheet is dropped by its own weight. When the sheet is abutted against the abutting member for positioning and aligned in the sheet conveying direction, the sheet abuts against the abutting member and rebounds, causing misalignment in the sheet conveying direction. In particular, if the paper transportation speed by the transportation means is high,
When the amount of pop-out discharged from the conveying means and reaching the sheet stacking table in which the stacking section is arranged in a slanted state becomes large, the sheet is lowered on the sheet stacking table and comes into contact with the lower sheet positioning abutting member. The amount of bounce is large. Further, in particular, when transporting small-sized paper, for example, A4 size paper or 8.5 × 11 inch size paper (1 inch is 25.4 mm), in order to ensure high-speed processing productivity, the stacking unit The time from the discharge of the final sheet to the binding process is short, and the binding process is executed before the rebound of the sheets is converged, so that the finish appearance quality of the sheet bundle deteriorates due to the sheet misalignment.

[0011]

The above-mentioned problems in the center folding process are solved by the following sheet post-processing device.

(1) In a sheet post-processing device that stacks sheets discharged from the image forming apparatus in a stacking unit and performs binding processing, a sheet width direction orthogonal to the sheet transport direction of the sheets placed in the stacking unit A sheet post-processing apparatus comprising: a width aligning unit that aligns the sheet and a vertical aligning unit that aligns the sheet conveying direction of the sheets placed on the stacking unit.

(2) In the sheet post-processing device in which the sheets discharged from the image forming apparatus are stacked on the stacking unit, the binding process is performed, and the stack of sheets is discharged by the discharge belt rotating in the stacking unit. An ejecting member that is held so as to be swingable and that abuts against an end portion of the sheet bundle when the discharge belt rotates, and a cutout portion that is formed in the sheet stacking table of the stacking unit. In the process of discharging the bundle of sheets by rotating the discharge belt, the pushing member stands up by being rocked by the sheet mounting table and pushes out the bundle of sheets, and the pushing member pushes the notch. A sheet post-processing apparatus, wherein the sheet post-processing apparatus swings and falls when it reaches a sheet, and retracts from an end portion of the sheet bundle.

(3) In a sheet post-processing apparatus for stacking sheets discharged from the image forming apparatus in a stacking unit by a transporting unit and performing a binding process, the transport linear velocity for transporting the sheet to the stacking unit is set to the sheet A sheet post-processing apparatus, which is variably controlled according to the size of the sheet.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION Next, an embodiment of a sheet post-processing apparatus of the present invention will be described with reference to the accompanying drawings.

[One Embodiment of Image Forming Apparatus] FIG. 1 is an overall configuration diagram of an image forming system including an image forming apparatus A, an image reading apparatus B, and a sheet post-processing apparatus (hereinafter referred to as a post-processing apparatus) C. .

In the image forming apparatus A, a charging means 2, an image exposing means (writing means) 3,
The image forming unit has the developing unit 4, the transfer unit 5A, the charge removing unit 5B, and the cleaning unit 6. The image forming unit uniformly charges the surface of the image carrier 1 by the charging unit 2 and then performs exposure scanning based on the image data read from the original by the laser beam of the image exposing unit 3 to form a latent image. Then, the latent image is reversely developed by the developing means 4 to form a toner image on the surface of the image carrier 1.

On the other hand, the paper S fed from the paper storage means 7A is sent to the transfer position. At the transfer position, the toner image is transferred onto the paper S by the transfer means 5A. After that, the electric charge on the back surface of the sheet S is erased by the charge eliminating unit 5B to be separated from the image carrier 1, conveyed by the intermediate conveying unit 7B, subsequently fixed by heating by the fixing unit 8, and ejected from the paper ejecting unit 7C. .

When images are formed on both sides of the paper S,
The sheet S heated and fixed by the fixing unit 8 is branched from the normal sheet discharge path by the transport path switching plate 7D, switched back in the reverse transport section 7E to reverse the front and back sides, and then passes through the image forming section again. Form an image on the back of S,
After passing through the fixing unit 8, the paper is ejected from the paper ejection unit 7C to the outside of the apparatus. The paper S discharged from the paper discharge unit 7C is processed by the post-processing device C.
Is sent to the receiving section 11 of.

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

On the upper part of the image forming apparatus A, an image reading apparatus B equipped with an automatic original feeding apparatus of a moving original reading type is installed.

[Construction of Post-Processing Apparatus] The post-processing apparatus C connected to the image forming apparatus A includes an entrance conveying section 10, a shift processing section 20, a stacking section 30, a stapling means (binding means) 40,
It is composed of a cover sheet feeding section 50 and a sheet discharging section 60.

The entrance conveyance section 10 conveys the sheet S discharged from the image forming apparatus A to each processing section. Shift processing unit 20
Shifts the sheet S conveyed from the entrance conveyance section 10 into a shift process and discharges the sheet S to an elevating and lowering tray 62, which will be described later. Accumulator 30
Stacks the sheets S conveyed from the entrance conveyance section 10 and performs stapling processing by stapling means 40 described later. The cover sheet feeding unit 50 feeds a cover sheet (hereinafter referred to as a cover sheet) K and conveys it to the shift processing unit 20 or the stacking unit 30.

The paper discharge unit 60 directly discharges and stores the paper S discharged from the image forming apparatus A through the entrance conveyance unit 10 without post-processing, a shift process or an end. An elevating and ejecting tray 62 for accommodating a bound sheet bundle,
It has a pair of discharge rollers 63 and a swing means 64.

[Paper Conveying Path of Post-Processing Apparatus and Upper Mechanism] FIG. 2 is a schematic view showing the paper conveying path of the post-processing apparatus C,
FIG. 3 is a sectional view showing the upper mechanism of the post-processing apparatus C.

In the post-processing apparatus C, the receiving section 11 for the sheets S carried out from the image forming apparatus A has a sheet discharging section 7C of the image forming apparatus A.
It is installed by adjusting the position and height to match with.

The conveying path for the sheet S connected downstream of the entrance roller pair 12 of the receiving section 11 in the sheet conveying direction has three systems: an upper first conveying path, an intermediate second conveying path, and a lower third conveying path. The sheet S is fed to one of the transport paths by selecting the angle occupied by the switching means G1 and G2.

(Paper discharged to the upper discharge tray 81) The image-formed paper S discharged from the image forming apparatus A is received by the receiving unit 11
And is conveyed by the pair of entrance rollers 12 and the entrance sensor PS1 for entrance passage detection detects the length of the paper S in the carrying direction. The sheet S passes through the passage 13 on the right side of the upper switching unit G1, and is nipped by the driving roller 14A and the driven roller 14B of the upper conveying roller pair 14,
After being conveyed and further nipped and conveyed by the conveying roller pair 15, the conveying roller pair 15 nips and discharges the sheet onto the upper sheet discharge tray 61 at the upper outside of the machine, and the sheets are sequentially stacked (first conveying path).

In this paper conveying process, the switching means G1
Is swung by the drive of the solenoid SD1, the passage 17 is closed, and the passage 13 is opened so that the sheet S can pass to the upper sheet discharge tray 61.

A maximum of about 200 sheets of paper S can be accommodated in the upper paper ejection tray 61, and the operator can easily take out the paper from the upper portion of the post-processing apparatus C.

(Shift processing or non-sorting) When this conveyance mode is set, the switching means G1 keeps the passage 13 closed and the passage 17 open while the solenoid SD1 is off, and the passage of the sheet S Allows 17 passages.

The image-formed sheet S discharged from the image forming apparatus A passes through the receiving portion 11 and the inlet roller pair 12, and passes through the passage 17 formed in an open state below the switching means G1. The sheet is sandwiched by the pair of transport rollers 18, passes through the passage 21 above the diagonally lower switching unit G2 that is the second transport path, is sandwiched by the pair of transport rollers 22, and passes through the passage 23, and then the pair of transport rollers (shift). (Roller pair) 24, and a discharge roller pair 63 composed of an upper drive roller 63A and a lower drive roller 63B is used to raise and lower the sheet discharge tray 62 outside the machine.
The sheet is discharged and placed on the upper side (second transport path). Reference numeral 64 denotes a swinging unit that swings the upper drive roller 63A with respect to the lower drive roller 63B so that the upper drive roller 63A can be sandwiched and separated.

A maximum of about 3000 sheets of paper S can be accommodated in the elevating and discharging tray 62.

[Binding Process] (Sheet Conveying) The image-formed sheet S which has been subjected to the image forming process in the image forming apparatus A and sent to the receiving section 11 of the post-processing apparatus C has the inlet roller pair 12, Switching means G
The sheet passes through the passage 17 below 1, is sandwiched by the pair of conveying rollers 18, and is conveyed to the third conveying path.

When a sheet S of a size larger than A4 or B5 is conveyed in the third conveying path, the solenoid SD2 is driven, the sheet S passes through the passage 31A below the switching means G2, and the downstream side is passed. It is nipped and conveyed by the conveying roller pair 32. The paper S is driven by the drive roller 3 further downstream.
Registration roller pair 3 including 4A and driven roller 34B
4 is sandwiched and sent out, is discharged to the space above the inclined sheet placing table 35, contacts the sheet placing table 35 or the upper surface of the sheet S placed on the sheet placing table 35, and slides up, and then the resist After the rear end portion of the sheet S in the traveling direction is discharged from the roller pair 34, the sheet S starts to descend due to its own weight, slides down on the inclined surface of the sheet stacking table 35, and the end binding protrusion near the stapling means 40. The leading end of the sheet S in the traveling direction contacts the sheet abutting surface of the abutting member 41 and stops.

In the third conveying path, small size sheets S of A4 size, B5 size, etc. are efficiently and continuously conveyed to improve copy productivity, so that the passage 31A below the switching means G1 is provided. A parallel passage 31B and a switching means G3 are provided.

Solenoid SD2 for switching means G2,
When the solenoid SD3 for the switching means G3 is driven together, the tip ends of the switching means G2, G3 both swing in the counterclockwise direction shown in the figure, closing the passages 21 and 31A and opening the passage 31B.

The leading end of the first sheet S sent out from the conveying roller pair 18 passes through the passage 31B and comes into contact with the peripheral surface of the registration roller pair 34 in the rotation stopped state to stop.

Next, the solenoid SD3 is de-energized, the tip of the switching means G3 swings clockwise, closing the passage 31B and opening the passage 31A. The leading end portion of the second sheet S sent out from the transport roller pair 18 passes through the passage 31A, comes into contact with the peripheral surface of the registration roller pair 34 in the rotation stopped state, and stops.

The registration roller pair 34 is driven and rotated at a predetermined timing, and the two sheets S are nipped and conveyed at the same time, and are discharged onto the sheet mounting table 35. The third and subsequent sheets are discharged one by one.

(Alignment) 36 is a width alignment means composed of a pair of width alignment members provided on both side surfaces of the sheet mounting table 35.
At least one of the width aligning members of the width aligning means 36 is movable in a direction orthogonal to the paper transport direction, and when the paper S is received on the paper loading table 35, it is opened wider than the paper width, and the paper is loaded. When descending on the table 35 and abutting against the end-stitching abutting member 41 and stopping, the side edges of the paper S in the width direction are tapped to align the width of the paper S (width alignment). At this stop position, when a predetermined number of sheets S are stacked and aligned on the sheet mounting table 35, the stapling means 40 performs a binding process to bind the sheets S.

(Binding Means) FIG. 4A is a plan view of the binding means for carrying out the binding process at two locations near the side edges of the sheet bundle Sa of various sizes.

Paper S of various sizes (for example, A4 shown in the figure)
The side edge portions of the B, B5, and A6 sizes are brought into contact with the end-stitching abutting member 41 to regulate the position in the transport direction.

The stapling means 40 is arranged at a position symmetrical with respect to the center line CL in the direction orthogonal to the sheet conveying direction.
It has a pair of staplers (binding machines) 401 and 402. Two
The staplers 401 and 402 of the set are sheets S of various sizes.
The staples SP1 and SP2 are struck at two centrally-distributed locations in the paper width direction in the vicinity of the side edge of the stapler.

FIG. 4B is a plan view of the binding means for performing the binding process at one corner of the sheet bundle Sa of various sizes.

The two sets of staplers 401 and 402 simultaneously move in the sheet width direction corresponding to sheets S of various sizes. The stapler 401 stops at a position near the corner of the sheet and is then driven to rotate by about 45 ° to strike the binding staple SP1.

(Paper discharge) A cutout is formed in a part of the paper stacking surface of the paper tray 35, and a plurality of discharge belts 38 wound around the drive pulley 37A and the driven pulley 37B rotate. Driven possible. A discharging claw (pushing member) 39 is integrally formed with a part of the discharging belt 38, and the tip end portion thereof draws an elliptical locus as indicated by a dashed line in the drawing. The stapled sheet bundle Sa is fed to the discharge belt 3
The rear end portion of the sheet bundle Sa is held by the ejecting claws 39 of No. 8 and is placed on the ejecting belt 38, slid on the placing surface of the sheet placing table 35 and pushed up obliquely upward, and the ejecting roller pair 63 is ejected. Proceed to the clamping position. 6 pairs of rotating discharge rollers
The sheet bundle Sa sandwiched by 3 is discharged and stacked on the elevating and discharging tray 62.

(Driving System of Stacking Unit and Paper Discharging Unit) FIG. 5 is a configuration diagram showing a driving system of the stacking unit 30 and the paper discharging unit 60.

The stepping motor M1 rotates the upper drive roller 63A of the discharge roller pair 63 via the timing belts B1 and B2 and the intermediate pulley P1, and also discharges the discharge roller pair 63 via the timing belts B3 and B4 and the intermediate pulley P2. The lower drive roller 63B is rotated.
The stepping motor M1 further rotates the drive pulley P3 via the intermediate pulley P2 and the timing belt B5,
The discharge belt 38 stretched between the drive pulley P3 and the driven pulley P4 is rotated.

The stepping motor M2 includes a driving roller 34A and a driven roller 34 arranged at the entrance of the stacking unit 30.
The registration roller pair 34 made of B is rotated, and further, the auxiliary transport belt 34D for transporting the rolled-in paper and the auxiliary transport roller 34E are rotated via the roller 34C.

[Cover Sheet Feeding] The cover sheet feeding section 50 is provided with a sheet feeding tray 5.
1, a movable bottom plate 52 and a lifting lever 53, and a cover sheet feeding means including a feeding roller 54, a sheet feeding roller 55, a separating roller 56 and the like (see FIG. 3).

One cover sheet K fed from the cover sheet feeding section 50 passes through the passage 57, passes through the position where the driving roller 14A and the driven roller 14C of the conveying roller pair 14 are held,
After passing through the passage 19 and the conveying roller pair 18, the conveying roller pair 32, the passage 33, and the registration roller pair 34 of the third passage
After that, the sheet reaches the sheet placing table 35.

The transport roller pair 14 is the drive roller 1 at the center.
4A and two driven rollers 14B and 14C that are in pressure contact with the drive roller 14A. When the drive roller 14A is driven to rotate to the left in the figure, the driven roller 14B rotates to the right and conveys the sheet S conveyed from the path 13 upward. At the same time, the driven roller 14C also rotates to the right to convey the cover sheet K conveyed from the passage 57 to the passage 19 below. Therefore, by the drive rotation of the drive roller 14A, the first
It is possible to simultaneously transport the paper S on the transport path and the cover sheet K on the fourth transport path in opposite directions.

[Vertical Alignment Means] FIG. 6 is a sectional view of the stacking unit 30 and the vertical alignment means 70.

Above the stacking unit 30, a vertical aligning unit 70 for aligning the sheet conveying direction of the sheets S placed on the stacking unit 30.
Are arranged.

(First driving means for vertical alignment means) The stepping motor M3 rotates the timing belt B6 which stretches the pulleys P5 and P6. The moving body 72 fixed to the timing belt B6 by the locking member 71 slides on the guide rod 73 and reciprocates. A vertical alignment pressing member 75 is fixed to the rotary shaft 74 fixed to the moving body 72, and the vertical alignment pressing member 75 can reciprocate together with the moving body 72.

The vertical alignment pressing member 75 is retracted to the initial position corresponding to the paper size. The sheet S nipped and conveyed by the pair of registration rollers 34 flies above the sheet mounting table 35 and is ejected. The leading end of the ejected paper S contacts the abutting surface 75a of the vertical alignment pressing member 75, and is placed on the surface of the paper placing table 35 that is inclined. Paper S
Switches back, and then descends on the sheet stacking table 35, and the trailing edge of the sheet S that has been carried in abuts against the edge-stitching abutting member 41 and stops.

Vertical alignment pressing member 75 installed at the initial position
Means that the small size paper S flies over the paper loading table 35,
It is prevented that it reaches a long distance, and is quickly brought into contact with the end-stitching abutting member 41.

When the final sheet S stacked on the sheet mounting table 35 comes into contact with the end-stitching abutting member 41,
The vertical alignment pressing member 75 is driven by the stepping motor M3 to move diagonally downward, presses the leading end of the sheet bundle Sa in the transport direction, and causes the trailing end of the sheet bundle Sa in the transport direction to act as the end-binding abutting member 41. The sheet bundle Sa is brought into contact with each other to align the sheets. The stapling means 40 performs a binding process on the bundle of sheets Sa that have been aligned.

(Second drive means for vertical alignment means) Moving body 7
The stepping motor M4 mounted on
The rotary shaft 74 is rotated via Z2, and the vertical alignment pressing member 75 fixed to the rotary shaft 74 is rockably rotated.

After the stapling means 40 binds the sheet bundle Sa, the vertical alignment pressing member 75 is driven by the stepping motor M4 and swung upward by about 90 ° to open the sheet bundle conveying path. The sheet bundle Sa for which the binding process has been completed is conveyed by pushing the rear end portion thereof up to the ejection claws 39 of the ejection belt, sandwiched by the ejection roller pair 63, and ejected onto the elevating ejection tray 62.

[Extrusion and discharge of sheet bundle] FIG. 7 shows sheet bundle Sa.
Sectional view showing the rotation of the pushing means 390 for pushing and discharging
FIG. 8 is a perspective view showing the rotation of the pushing means 390. Figure 9
FIG. 9A is an enlarged cross-sectional view showing the final position where the pushing member 391 of the pushing means 390 stands up and pushes out the sheet bundle Sa.
(B) is an enlarged cross-sectional view showing a state in which the pushing member 391 is tilted and retracted.

A guide plate 39 is provided below the paper table 35.
2 is installed in parallel with the paper table 35. A notch 392a is formed in the portion near the upper end of the guide plate 392 and near the drive roller 34A.

A support shaft 38a fixed to a part of the discharge belt 38 rotatably supports the pushing member 391.
A roller 393 is provided on the side surface of the pushing member 391 of the pushing means 390.
Is rotatably supported.

In the process of ejecting the bundle of sheets Sa by rotating the ejecting belt 38, the pushing member 391 rolls up the roller 393 on the upper surface of the guide plate 392, is prevented from rocking, and stands up.
The sheet bundle Sa is pushed out.

When the push-out member 391 reaches the cutout portion 392a, the roller 393 falls into the cutout portion 392a, and the push-out member 391 integrated with the roller 393 swings and falls due to its own weight to eject the sheet bundle Sa. Retreat from the rear end in the direction. Thereafter, the pushing member 391 is supported by and suspended from the discharge belt 38, and advances below the bottom surface side of the guide plate 392 together with the discharge belt 38, and is stopped at the initial position.

[Control of Paper Conveying Speed to Stacking Section] In the stacking section 30 shown in FIG. 3, the sheet S sandwiched between the registration roller pair 34 including the driving roller 34A and the driven roller 34B and discharged is discharged onto the sheet loading table 35. After being discharged to the upper space of the sheet and placed on the sheet mounting table 35, the sheet is lowered on the inclined surface of the sheet mounting table 35, and the leading end of the sheet S in the descending direction abuts on the end-binding abutting member 41. Stop.

In the drive system of the integrated unit 30 shown in FIG. 5,
The stepping motor M2 drives and rotates the registration roller pair 34. The control means variably controls the drive rotation speed of the stepping motor M2 in response to the size setting signal of the paper S, and makes the paper transport linear speed of the registration roller pair 34 variable.

Small size paper S, for example, A4 size paper or 8.5 × 11 inch size paper (1 inch is 25.4 m
m) is post-processed, the linear velocity of the sheet conveyance of the registration roller pair 34 is decelerated, and the distance and arrival time for the small-sized sheet S to come in contact with the sheet mounting table 35 are shortened.

Reduced linear velocity of small-size paper (first
The sheet S discharged by the linear velocity V1 of the sheet is placed at a short distance on the sheet loading table 35, and then descends on the inclined sheet loading table 35 for a short distance and in a short time to eject the end-binding stitch. Since it abuts against the abutting member 41, there is no occurrence of sheet misalignment due to rebound when abutting, and alignment is promptly performed.

Particularly, in the post-processing apparatus C connected to the image forming apparatus A capable of high-speed processing, after the final sheet S is discharged by the registration roller pair 34, it comes into contact with the end-stitching abutting member 41. Since the transport time until the sheets are aligned and bound is short, the distance to reach the ground on the sheet placement table 35 and the arrival time can be shortened, thereby ensuring productivity of high-speed processing and preventing sheet misalignment. It is effective in improving the finished appearance quality of Sa.

On the other hand, when a large size sheet S, for example, A3 size sheet or 11 × 17 inch size sheet (1 inch is 25.4 mm) is post-processed, it is discharged by the pair of registration rollers 34. In this case, since the excess distance of the sheet S is small and the sheet S is quickly grounded on the sheet placing table 35 due to its own weight, the linear velocity (second linear velocity) V2 of the large-size sheet of the registration roller pair 34 is increased. Stable sheet ejection and sheet alignment are performed with the sheet being maintained at a high speed.

The sheet discharging speed of the registration roller pair 34 driven by the stepping motor M2 is, for example, a large-size sheet conveying linear velocity (second linear velocity) V2 of 600 mm.
/ Sec, the small-size sheet conveying linear velocity (first linear velocity) V1 is set to 500 mm / sec.

In the embodiment of the present invention, the post-processing device connected to the copying machine is shown. However, the present invention is also applicable to the post-processing device connected to an image forming apparatus such as a printer or a light printing machine. Applicable.

[0075]

As described above, the following excellent effects can be obtained by the sheet post-processing apparatus of the present invention.

(1) When the inclined sheet placing table is lowered by its own weight and the sheet is brought into contact with an abutting member for positioning the leading end portion of the sheet in the sheet advancing direction, the sheet is dropped. The rear end portion in the direction is pressed and aligned by the vertical aligning and pressing member of the vertical aligning means, and the leading end of the paper is pressed against the end-stitching abutting member, whereby the consistency in the traveling direction of the paper is improved. The appearance quality of the sheet bundle is improved.

(2) When the binding-processed sheet bundle is held and moved by the pushing member fixed to the rotating discharge belt and the sheet is discharged by being moved, the pushing member is retracted from the sheet-bundle conveying path. As a result, it is possible to prevent the rear end of the sheet bundle in the sheet traveling direction and the pushing member from interfering with each other when the sheet bundle is discharged, thereby causing damage to the sheet bundle and deteriorating the finished appearance quality of the sheet bundle.

(3) When the small size paper is conveyed onto the paper placing table, the paper conveyance linear velocity is set to the low first linear velocity V1.
By limiting the protrusion distance and time of small-size paper by decelerating the paper to abut, it quickly abuts the end-stitching abutting member, prevents rebound, and prevents misalignment in the paper advancing direction. The consistency of the bundle is improved, and the finished appearance quality of the sheet bundle after the binding process is improved. Also,
By increasing the linear velocity for transporting large-sized sheets to the sheet mounting table to the high second velocity V2, stable ejection of large-sized sheets was realized.

[Brief description of drawings]

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

FIG. 2 is a schematic diagram showing a sheet conveyance path of a post-processing device.

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

FIG. 4 is a plan view of a binding unit that performs binding processing on two locations near a side edge portion or one location on a corner of a sheet bundle of various sizes.

FIG. 5 is a configuration diagram showing a drive system of a stacking unit and a paper discharge unit.

FIG. 6 is a cross-sectional view of a stacking unit and a vertical alignment unit.

FIG. 7 is a cross-sectional view showing the rotation of a pushing unit that pushes out a bundle of sheets.

FIG. 8 is a perspective view showing the rotation of the pushing means.

FIG. 9 is an enlarged cross-sectional view showing a final position where the pushing-out member of the pushing-out unit stands up and pushes out the sheet bundle, and an enlarged cross-sectional view showing a state where the pushing-out member falls and is retracted.

[Explanation of symbols]

30 accumulation section 35 paper loading table 38 Discharge belt 39 Discharge claw (extruded member) 390 Extruding means 391 Extruded member 392 guide plate 393 Coro 40 Staple means (binding means) 41 End binding butting member 60 Paper output section 70 Vertical alignment means 72 Mobile 73 Guide rod 74 rotation axis 75 Vertical alignment pressing member A image forming apparatus C Paper post-processing device (post-processing device) V1 Small size paper transport linear velocity (first linear velocity) V2 Large size paper transport linear velocity (second linear velocity)

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) B65H 31/30 B65H 31/30 3F108 31/34 31/34 43/00 43/00 G03G 15/00 534 G03G 15/00 534 (72) Inventor Hiroyuki Wakabayashi 2970 Ishikawa-cho, Hachioji, Tokyo Konica stock company (72) Inventor Masahiro Kaneko 2970 Ishikawa-cho, Hachioji, Tokyo Konica stock company (72) Inventor Tadahiro Takahashi Tokyo Tokyo City Hibarigaoka 3-chome 3 (72) Inventor Yasumasa Nakamura 1-2-26 Matsubara-cho Akishima-shi, Tokyo F-term (reference) 2H072 CA01 CA05 GA08 HB10 JA03 3F048 AA02 AA04 AA05 AB01 BA07 BB03 EB24 EB29 3F049 BA02 EA10 LA14 LB03 3F054 AA01 AC02 AC03 AC05 BA04 BG04 BG11 BH05 BH07 BH13 BH14 BJ08 3F102 AA09 AA13 AB01 AB04 BA09 BB02 BB04 EA14 EB01 EB02 3F108 GA02 GA03 GA04 GB01 GB07 HA39

Claims (6)

[Claims] 1. A sheet post-processing apparatus that stacks sheets discharged from an image forming apparatus in a stacking unit and performs binding processing.
Width alignment means for aligning a paper width direction orthogonal to the paper transport direction of the paper placed on the stacking portion, and vertical alignment means for aligning the paper transport direction of the paper loaded on the stacking portion. A sheet post-processing device characterized by the above. 2. The vertical alignment means is supported by a leading end abutting member for positioning a leading end portion of a sheet placed in the stacking section in a sheet traveling direction, and reciprocally movable in a sheet transport direction of the stacking section, The sheet post-processing apparatus according to claim 1, further comprising a vertical alignment pressing member that presses a rear end portion of the sheet in the sheet advancing direction to bring the front end portion of the sheet into contact with the front end abutting member. 3. The first alignment means comprises a first drive means for reciprocally moving the vertical alignment pressing member in the sheet transport direction in accordance with the length of the sheet placed in the stacking section in the sheet transport direction.
The sheet post-processing apparatus according to claim 1, further comprising a second driving unit that retracts the bound sheet bundle from the sheet transport path when the sheet bundle is discharged. 4. A sheet post-processing apparatus that stacks sheets discharged from an image forming apparatus in a stacking unit, performs binding processing, and discharges a bundle of sheets by a discharge belt that rotates in the stacking unit. And a push-out member that is swingably held and abuts against the end portion of the sheet bundle when the discharge belt rotates, and a cutout portion formed in the sheet stacking table of the stacking unit. In the process of discharging the bundle of sheets by rotating the discharge belt, the pushing member stands up by being rocked by the sheet mounting table and pushes out the bundle of sheets,
The sheet post-processing apparatus, wherein the push-out member swings and falls when it reaches the cutout portion, and retracts from an end portion of the sheet bundle. 5. A sheet post-processing apparatus that stacks sheets discharged from an image forming apparatus in a stacking unit by a transport unit and performs a binding process by setting a transport linear velocity for transporting the sheets to the stacking unit. A sheet post-processing device that is variably controlled according to size. 6. The sheet post-processing according to claim 5, wherein the control of the transport linear velocity sets the transport linear velocity of the large size sheet higher than the transport linear velocity of the small size sheet. apparatus.