JP2000272810A - Sheet-treating equipment and image-forming equipment having sheet-treating equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable positive matching even to a sheet having a curl. by preventing the dislocation of a loading sheet in sheet-treating equipment. SOLUTION: A sheet P transported by means of a pair of transport rollers 5 is loaded on a matching tray 8. In butting the extreme part to a sheet extremity stopper 11 for matching the transport direction, the rear end of the sheet is lifted, using the sloped surface of a sheet rear end pressing rib 9 to guide the rear end of the sheet to the pushing direction in the transport direction. Thus, the loaded sheet is prevented from dislocation in the transport direction to enhance the matching and to optimize binding treatment for a sheet bundle.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a sheet processing apparatus,
More particularly, the present invention relates to, for example, a sheet processing apparatus for aligning and binding a sheet bundle and an image forming apparatus including the apparatus.

[0002]

2. Description of the Related Art Conventionally, a sheet binding apparatus (sheet processing apparatus) for aligning a plurality of sheets and binding an end portion of a sheet bundle formed by the alignment is as follows. Was common.

A sheet on which an image is created by the image forming apparatus main body is discharged at a predetermined timing from a predetermined discharge port of the image forming apparatus main body. The sheet is received from the receiving port of the sheet binding device, and the sheet transporting roller sandwiches the sheet and transports the sheet to the sheet binding section. After that, a predetermined number of sheets are stacked on the sheet stacking unit on which sheets to be bound are stacked.

[0004] The stacked sheets are aligned in the sheet conveying direction and the sheet width direction orthogonal to the conveying direction before the sheet binding process is performed. After the sheet bundle is aligned, the sheet binding means performs the binding operation of the designated sheet bundle.
Note that such sheet binding processing may be performed at a position where the sheet bundle is aligned, or may be such that the aligned sheet bundle is transported together with the bundle to the sheet binding position and the sheet binding processing is performed at the position.

In the aligning operation, normally, a rotating member such as a belt, a roller, a paddle or the like, or a reciprocating member in the sheet conveying direction is arranged on an abutting portion provided on the leading end side in the sheet conveying direction, and is contacted with the rear end of the sheet. The sheet conveyance direction is aligned by abutting the sheet edge with a pressing member or the like that contacts and presses the sheet edge against the abutting portion.Furthermore, the alignment in the sheet width direction, which is a direction orthogonal to the sheet conveyance direction, reciprocates in the sheet width direction. This is performed by an alignment plate that is movable and that operates to sandwich the sheets stacked on the sheet stacking unit from both sides.

The stapled sheet bundle is provided at a position where a user can take out the sheet bundle by a discharge means such as a roller pair for conveying the sheet bundle, a belt member, or a conveying member which pushes out the sheet bundle. The sheet is discharged onto a sheet discharge tray of the sheet processing apparatus.

By repeating the above operation for the required number of sheet bundles, the sheet bundles are sequentially discharged onto the sheet discharge tray and stacked.

[0008]

However, in the above-mentioned conventional example, the following improvements are desired.

In a sheet processing apparatus for performing a predetermined process on a sheet, it is necessary to accurately align a sheet before processing, on which an image is formed and conveyed to the sheet processing apparatus. Therefore, before performing a predetermined processing operation, a sheet stacking unit for temporarily stacking the conveyed sheets is provided,
The matching operation is performed at that position.

However, due to factors such as the sheet conveyance state and the type of sheet, it may not be possible to perform sufficient alignment.

For example, if the ends (leading end and trailing end) of the sheet in the sheet conveying direction have curls, even if the sheet is to be aligned in the sheet conveying direction, the sheet does not correctly hit the contact portion, Will be reduced.

Further, when the sheet is discharged to the sheet stacking section, the sheet is greatly displaced in a direction different from the discharge direction due to the force of discharge, and deviates from a position on the sheet stacking section which enables appropriate alignment operation. Sometimes.

In order to solve these problems, it is conceivable to provide a curl removing member for removing the curl of the sheet during sheet conveyance or a large aligning device. However, by providing such a member, the sheet processing apparatus becomes large. And the product cost also rises significantly.
This was inconsistent with the user's desire for lower costs.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problem, and it is intended to prevent a sheet carried into a sheet stacking means from being displaced, and to reliably perform sheet alignment and binding processing even for a curled sheet. It is an object of the present invention to provide a sheet processing apparatus capable of performing such sheet processing as described above, and an image forming apparatus including the sheet processing apparatus.

[0015]

According to the present invention, there is provided a discharge unit for conveying and discharging a sheet on which an image is formed, a sheet stacking unit on which the sheets discharged by the discharge unit are stacked, An abutting reference member provided on a sheet leading end side in a direction in which a sheet is discharged onto the sheet stacking unit and against which the leading end of the sheet discharged on the sheet stacking unit is abutted; And a biasing member that is provided on a rear end side of the sheet in a direction in which the sheet is discharged, and biases the sheet discharged from the discharge unit toward the abutting reference member.

Further, the biasing member is provided on the sheet stacking means.

Further, the urging member has an urging surface with which the trailing end of the sheet discharged from the discharging means abuts, and the urging surface is inclined downward toward the abutting reference member. Surface.

Further, the sheet stacking means of the sheet stacking means is substantially horizontal.

Further, the biasing member is a plurality of ribs provided at intervals in a sheet width direction orthogonal to the sheet discharging direction.

The urging member has an urging surface on which the trailing end of the sheet discharged to the sheet stacking means is stacked.
The urging surface has an inclined surface that is lowered toward the abutting reference member.

Further, the sheet stacking means of the sheet stacking means is substantially horizontal on the side of the abutting reference member.

[0022] Further, there is provided a conveying means for contacting the sheet discharged onto the sheet stacking means by the discharging means and conveying the sheet in the direction of the abutting reference member.

Further, the conveying means is a belt which rotates in a sheet conveying direction.

Further, the sheet is discharged from the discharging means onto the sheet stacking means, and after the leading end of the sheet comes into contact with the abutting reference member, the width aligning means aligns in the sheet width direction orthogonal to the sheet conveying direction. It is characterized by having.

The width aligning means is a plate member provided opposite to both ends in the width direction of the sheet so as to contact an end portion in the sheet width direction. It is characterized in that one of the members moves in a direction to sandwich the sheet and aligns in the sheet width direction.

Further, a roller member rotatable in the sheet conveying direction and having a substantially conical shape on the opposite side to the plate member is provided on a surface of the plate member which comes into contact with a sheet end. It is characterized in that the upper side of the sheet side is pressed during the sheet alignment operation by the plate member.

Further, the aligning operation of the width aligning means is performed every time a sheet is stacked on the sheet stacking means.

Further, there is provided a sheet binding means for performing a process for binding sheets stacked on the sheet stacking means.

Further, a tip holding member is provided near the abutting reference member and presses the leading edge of the sheet in contact with the abutting reference member in the direction of the sheet stacking means.

Further, the urging member is provided integrally with the sheet stacking means.

[0031]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a sheet processing apparatus embodying the present invention and an image forming apparatus provided with the apparatus will be described in detail with reference to the drawings.

FIG. 1 shows an example of an image forming apparatus provided with a sheet processing apparatus according to the present invention. The image forming apparatus may be a copier or a printer using an electrophotographic process, or a copier or a printer using an inkjet image recording method as long as it forms an image on a sheet.
Means for forming an image is not limited. In this embodiment, a copying machine using an electrophotographic process will be exemplified.

The image forming apparatus main body (copier main body) 900 includes a platen glass 906 as a document placing table on which a document is placed for reading an image, and a light source 90 for irradiating the document.
7. An image reading unit having a lens system 908 for collecting light reflected by the original, an image reading unit having an automatic original feeder 940 for realizing automatic feeding of the original, and a sheet for forming an image are stored. A sheet cassette 910 as a sheet storage means detachably provided in the apparatus main body;
911, a sheet feeding member 941 that separates and feeds the sheets stored in the sheet cassette one by one, and synchronizes the fed sheet with an image forming timing to form the image forming unit 9.
02, a photosensitive drum 914 for forming an electrostatic latent image, a developing means 915 for developing the electrostatic latent image on the drum 914, and a toner formed on the photosensitive drum 914. An image forming unit 902 having a transfer unit 916 for transferring an image to a sheet, a separating unit 917 for separating the transferred sheet, a conveying belt 920 for conveying the sheet on which the image is transferred, and a fixing unit for fixing the image on the sheet A fixing device 904 as means is provided.

A sheet processing apparatus A embodying the present invention is provided below the copying machine 900 as the image forming apparatus.
Is arranged. The sheet processing apparatus A will be described later in detail.

An image forming operation in the copying machine will be described.

When a signal for starting image formation is input from a user or an external terminal to a control unit (not shown) of the copying machine 900, a sheet feeding member 941 is fed from the sheet cassettes 910 and 911.
Feeds the sheet S. On the other hand, the light source 907 irradiates the original D placed on the platen glass 906 with light while moving. The light reflected by the original D is transmitted through the lens system 9
The light is irradiated onto the photosensitive drum 914 via the reference numeral 08. The surface of the photosensitive drum 914 is uniformly charged in advance by a primary charger 919, and an electrostatic latent image is formed by irradiation with light. Next, the electrostatic latent image is developed by the developing device 915 to form a toner image on the photosensitive drum 914.

The skew of the sheet S fed by the sheet feeding member 941 is corrected by the registration rollers 901, and the timing of the image forming operation is synchronized with the timing of the image forming operation.
Sent to 2. In the image forming unit 902, the photosensitive drum 91
The toner image of No. 4 is transferred to the sheet S that has been sent by the transfer charger 916, and the sheet S to which the toner image has been transferred is charged by the separation charger 917 to a polarity opposite to that of the transfer charger 916. It is separated from the photosensitive drum 914.

Then, the separated sheet S is conveyed to the fixing device 904 by the conveying belt 920, and heat and pressure are applied by the fixing device 904 to fix the image on the sheet S. The sheet S on which the image is fixed is discharged out of the apparatus by a discharge roller pair 905, or conveyed from the apparatus main body 900 to the entrance 1 of the sheet processing apparatus A by a main body discharge roller (main body discharge means) 921.

(First Embodiment) Next, a sheet processing apparatus according to the present invention will be described in detail as a first embodiment of the present invention. FIG. 2 is a vertical sectional side view of the sheet processing apparatus A.

As shown in the figure, a sheet processing apparatus A embodying the present invention is disposed below a copying machine main body 900 indicated by a virtual line. Reference numeral 2 denotes an entrance conveying roller pair arranged at the entrance of the sheet. Reference numeral 3 denotes an entrance sensor for detecting that the sheet P has entered the sheet binding apparatus A as a sheet processing apparatus. Reference numeral 4 denotes a conveying sheet P. A guide plate 5 for guiding to the sheet processing section, a discharge roller pair as discharge means for conveying and stacking the sheet P to the sheet processing section, and a sheet position detecting lever 6 disposed near the conveyance roller pair 5 are shown.

Reference numeral 7 denotes an upper sheet guide plate when the sheet is discharged by the discharge roller pair 5. The upper sheet guide plate 7 guides the sheet P to the alignment tray 8, which will be described later. Reference numeral 8 denotes an alignment tray which is provided substantially horizontally and serves as a sheet stacking means for temporarily stacking the sheets P discharged by the discharge roller pair 5 and aligning the sheets.

Reference numeral 9 denotes a sheet rear end urging rib as an urging member for urging the rear end of the sheet discharged onto the alignment tray 8 in the transport direction, and the sheet P is pushed out in the discharge direction ( (Biased) as shown in FIG. Note that a plurality of sheet rear end urging ribs 9 are provided at intervals in the sheet width direction orthogonal to the sheet conveyance direction on the alignment tray 8. Providing a plurality of sheet rear end urging ribs 9 at intervals can reduce frictional resistance with the rear end of the sheet that comes into contact. The sheet rear end urging rib 9 will be described later in detail.

Reference numeral 10 denotes an alignment tray 8 by a discharge roller 5.
A transport belt as transport means for transporting the sheet P discharged upward to a downstream side in the transport direction, wherein the contact area between the sheet and the belt 10 increases as the number of stacked sheets increases. Belt. The conveyance belt 10 abuts the leading end of the sheet discharged onto the alignment tray 8 and a sheet leading end stopper 1 serving as a reference member.
In order to hit the sheet 1, the sheet rotates while contacting the sheet. However, even after the leading edge of the sheet strikes the sheet leading end stopper 11, the sheet contacts the uppermost sheet and rotates in the transport direction to urge the sheet.

However, the conveyance belt 10 may cause the sheet P to climb over the stopper 11 after hitting the sheet front end stopper 11 or to buckle between the sheet front end stopper 11 and the conveyance belt 10. For the purpose of preventing jam, after the sheet P collides with the sheet leading end stopper 11, only a sheet conveying force enough to cause a slip with the conveying belt 10 is applied.

Reference numeral 12 denotes a conveyance guide for receiving the sheet P from the guide 7 and guiding the sheet P to the conveyance belt 10;
Is a static elimination brush attached to the conveyance guide and for neutralizing the sheet P. The tip of the brush is always in contact with the uppermost sheet on the alignment tray 8, and the sheet P is in contact with the static elimination brush 13. In order to prevent the sheet from returning in the direction opposite to the sheet conveyance direction, the sheet is arranged at an angle that becomes a counter with respect to the sheet return direction.

Reference numeral 14 denotes a sheet bundle conveying upper roller which is disposed at a position substantially coincident with the axial direction of the conveyor belt 10 and at a position shifted from the conveyor belt 10. The sheet bundle conveying upper roller 14 is held by a horizontally extending arm 15 a of a two-armed lever 15, and the bundle conveying roller solenoid 4
3 (FIG. 8) can be moved up and down by turning on and off.

Reference numeral 16 denotes a lower roller of the sheet bundle transport disposed at a position facing the upper roller 14 of the sheet bundle transport with the sheet P interposed therebetween. The sheet bundle conveying lower roller 16 is rotated by being transmitted with driving by a bundle conveying motor 55 (FIG. 8).

Reference numeral 17 denotes a stacking detection lever for detecting that sheets are stacked on the alignment tray 8, and reference numeral 18 denotes a curl pressing lever 18 as an abutting reference member for suppressing curling at the leading end of the sheet. It is arranged in multiple directions. Reference numeral 19 denotes a bundle discharge upper roller for discharging the sheet bundle from the alignment tray 8. Reference numeral 21 denotes a bundle discharge lower roller provided opposite to the sheet discharge upper roller 19. The upper bundle discharge roller 19 is configured to be displaceable by the rotation of the lever 20 supporting the upper bundle discharge roller 19 so that the upper bundle discharge roller 19 can be separated from and brought into contact with the lower bundle discharge roller 21.

Reference numeral 22 denotes a discharge sensor provided near the bundle discharge roller pair 19, 21; 23, a discharge stacking tray for stacking sheets discharged from the alignment tray 8; and 24, discharge onto the discharge stacking tray 23. This is a full-load detection lever that detects the loaded state of the sheets P that have been placed.

Reference numeral 25 denotes a conveyor belt holder for regulating both sides of the conveyor belt 10 with a predetermined distance, and reference numeral 26 denotes a plate member of a width aligning means for moving and aligning the sheet in a sheet width direction which is a direction orthogonal to the sheet conveying direction. Matching plate, 2
Reference numeral 7 (FIG. 5) denotes a substantially conical rotatable roller (roller member) provided on a surface of the alignment plate 26 which comes into contact with the sheet. Reference numeral 28 denotes a width adjustment unit provided opposite the alignment plate 26. A side plate of the apparatus as a plate member, 29 is a conical rotatable roller (roller member) provided on the facing surface of the side plate 28, 30, 31
Is a sheet reference surface provided on the side plate 28.

Reference numeral 32 indicated by a virtual line denotes a staple device as sheet binding means for binding sheets. The sheet binding means 32 is arranged so that a predetermined position of the sheet bundle can be bound in a direction parallel to the sheet conveying direction.

In FIG. 3, a frame 47 of the transport belt holder 25 is held on a support shaft 45, and the support shaft 45 is brought into contact with the transport belt 10 and a roller 46 for rotating the transport belt 10 (FIG. 4). ) Is provided.

In the frame 47, the conveying belt 10 is displaced in the same direction by the action of the sheet P moved by an alignment operation in the sheet width direction described later, and the alignment plate 26 ends the alignment operation and separates from the sheet. In this case, the transport belt 10 is provided to regulate the transport belt 10 in order to prevent the sheet P from shifting due to the restoring force of the transport belt 10 that has been displaced to return to the original position.

Next, the sheet processing operation according to the above configuration will be described with reference to FIGS. First, a flow from when an image-formed sheet P is conveyed toward the sheet binding device A and stacked on the alignment tray 8 will be described.

The sheet P discharged from the image forming apparatus main body 900 is conveyed in the direction of the sheet binding apparatus A with its leading end being held between the entrance conveying rollers 2. At this time, the entrance sensor 3 detects that the sheet P is being conveyed in the direction of the sheet binding device A, and the detection information is transmitted to the CPU 61. The sheet P is a guide plate 4
The paper is conveyed in the direction of the alignment tray 8 by the discharge roller pair 5 and is discharged while being guided. The sheet position detection lever 6 can detect whether or not the sheet P has been completely discharged by the discharge roller pair 5.

When the sheet P is conveyed onto the alignment tray 8 by the discharge roller pair 5, the leading end of the sheet is
0, and enters the nip formed by the alignment tray 8 and is conveyed to the downstream side by the conveyance force given by the conveyance belt 10 and the conveyance roller pair 5, and the sheet rear end is ejected by the discharge roller pair. Exhausted from 5

When the leading edge of the sheet strikes the sheet leading end stopper 11, the conveying force of the conveying belt 10 is small, so that the proof stress of the sheet striking the sheet leading end stopper 11 overcomes the conveying force, and the conveying belt 10 It will slip on the surface. As a result, the sheet P always waits on the alignment tray 8 while receiving a light conveyance force in the conveyance direction.

Next, the alignment of the sheets P stacked on the alignment tray 8 in the width direction will be described with reference to FIG.

As described above, the sheet leading end stopper 11
After the sheet P abutting on the alignment tray 8 enters the standby state on the alignment tray 8, the alignment plate 26 moves upward from the standby position 26A indicated by the dashed line to the side plate 28 of the apparatus. The sheet P stacked on the alignment tray 8 by this movement comes into contact with the alignment plate 26 and abuts the reference surface 3 provided on the side plate 28.
It is pushed to the position where it comes into contact with 0 and 31 securely. The above-described operation of the matching plate 26 is performed by rotation of a drive motor 49 (FIG. 5) included in the matching plate driving mechanism 50 shown in FIG.

Note that the sheet P may have curls in the sheet width direction orthogonal to the sheet conveying direction. When the sheet P having a curl as shown in FIG. 5 is pressed against the abutting reference surfaces 30 and 31 by the operation of the alignment plate 26, the side end of the sheet P is pressed by the action of the curl. It slides in the curl direction (upward) along 31.

In such a situation, the sheet alignment deteriorates. In the present invention, the aligning plate 26 and the side plate 28 are provided with rollers 27 and 29 which are rotatable and whose free ends are conical. It is. Even when the sheet P curled by the rollers 27 and 29 is aligned, the side edge of the sheet can be prevented from slipping above a predetermined height where the rollers are provided, and the alignment in the sheet width direction is improved. Can be improved.

Further, since the free ends of the rollers 27 and 29 which are not held by the alignment plate 26 and the side plate 28 have a conical shape, even if the sheet P is curled, the end of the sheet P is maintained at a predetermined height. It can be easily guided. In addition, roller 2
Since the seats 7 and 29 are configured to be rotatable, the sheet P
No resistance in the transport direction.

Regarding the alignment of the sheet P, the operation of the alignment plate 26 will be further described.

The width of the sheet P varies.
Since the state in which the sheet P is curled differs for each sheet, the distance between the alignment plate 26 and the abutment reference surfaces 30, 31 during alignment is set to be shorter than the sheet width of the sheet size to be conveyed. Is set to

Also, when aligning a thick sheet having a strong stiffness or when aligning a large number of sheets, the aligning plate 26 is moved to a position smaller than the sheet width, so that a large load is applied to the drive motor 49 of the aligning plate 26. The load may shorten the life of the drive motor 49 or cause the motor to step out due to the load during the matching operation.

Therefore, an elastic member (not shown) is disposed between the matching plate 26 and the driving mechanism 50, and when the matching plate 26 receives a load exceeding a predetermined value, the direction opposite to the matching direction (the direction of the standby position). ) Is configured to escape.

The above-described aligning operation is performed every time the set number of sheets P for performing the sheet binding process are discharged and stacked on the aligning tray 8, and are sequentially aligned.

Next, the alignment operation in the sheet conveying direction will be described with reference to FIG.

As described above, the sheet P is discharged onto the alignment tray 8, conveyed by the conveying belt 10, and is brought into a state where it abuts against the sheet leading end stopper 11.
Some sheets P on which images have been formed are curled in the sheet conveying direction. Even in a sheet having a curl at the leading end, there is a possibility that the consistency of the sheet may deteriorate as in the case of a sheet having a curl in the sheet width direction.

For this reason, in the present embodiment, the leading end of the curl holding lever 18 is used so that the sheet P having a curl at the leading end can be properly aligned.
Is pressed down from above.

The curl press lever 18 whose end is supported by the support shaft 41 is turned on / off by a curl press lever solenoid 48.
It is configured to be displaced by an OFF operation between a position where the sheet is pressed and a position where the sheet is separated from the sheet. The plurality of curl pressing levers 18 are arranged in the width direction of the sheet P, and press the leading end curl of the sheet so that the leading end of the sheet abuts the sheet leading end stopper 11 substantially perpendicularly, thereby ensuring the leading end alignment. Is possible.

During the sheet stacking operation and the aligning operation, the solenoid 48 of the curl holding lever 18 is turned off.
Therefore, it is in contact with the alignment tray 8 by its own weight.
The transport belt 10 side of the curl press lever 18 has a tapered surface so that the sheet P discharged onto the alignment tray 8 can easily enter between the curl press lever 18 and the alignment tray 8. Conveyed sheet P
Can be slid into the lower part of the curl holding lever 18.

Next, the operation of the sheet rear end urging rib 9 for urging the sheet rear end when the image-formed sheet is discharged from the discharge roller pair 5 onto the alignment tray 8 and stacked is shown in FIG. It will be described using FIG.

FIG. 6 shows that the sheet P is discharged from the discharge roller pair 5 and falls on the alignment tray, and the sheet leading end stopper 1 is moved.
1 shows a state where the sheet is being conveyed by a conveying belt to one side. The sheet P is discharged onto the alignment tray 8 by the discharge roller pair 5, and at this time, the discharge roller pair 5
At the moment when the rear end of the sheet P comes out of the nip portion, a force acts on the sheet P to return in the direction opposite to the sheet conveying direction due to the effect of the sheet stiffness and bending. Further, there is also a case where the impact is dropped to the rear of the aligning tray 8.

The leading edge of the sheet is sandwiched between the transport belt 10 and the alignment tray 8, and a transport force is applied from the transport belt 10 in the direction of the sheet distal stopper 11, but as described above, the transport force of the transport belt 10 is extremely high. Therefore, the sheet P may return in the reverse direction from the sheet conveyance direction due to the rear end of the sheet being shifted rearward or losing the force to return.

In such a situation, the transport belt 1
0 and the leading end side of the sheet nipped by the alignment tray 8 is shifted in the direction opposite to the conveying direction, so that a sufficient conveying force cannot be obtained from the conveying belt 10 and the sheet cannot be conveyed. Further, in the worst case, the front end of the nipped sheet comes out of the nip portion between the conveyance belt 10 and the alignment tray 8 in the direction opposite to the conveyance direction.

In such a situation, the consistency in the sheet conveying direction is deteriorated. Such a phenomenon is more conspicuous for a thick sheet, a large-sized sheet, a sheet having a large coefficient of friction between sheets, and when a large number of sheets are stacked on the alignment tray 8.

Therefore, by holding the rear end of the sheet P discharged from the discharge roller pair 5, it is possible to prevent the sheet P from returning in the direction opposite to the conveying direction, and to urge the sheet P in the conveying direction. A sheet rear end urging rib 9 is provided. As shown in FIG. 6, the sheet abutting surface which is the urging surface of the sheet rear end urging rib 9 is an inclined surface 9a, and the rear end of the sheet P discharged from the discharge roller pair 5 is an inclined surface. Contact 9a. By lifting the rear end of the sheet as shown in the figure, it is possible to prevent the sheet from returning rearward due to a drop impact or the like.

Further, the inclined surface 9a, which is the urging surface, has a function that the rear end of the sheet slides down onto the alignment tray 8 along the inclined surface 9a. The inclined surface 9a is the sheet leading end stopper 1.
1, the sheet P that has contacted the inclined surface 9 a slides in the sheet conveying direction. Thus, even if the conveyance belt 10 has a slight conveyance force, the sheet P can be smoothly conveyed because the sliding force of the sheet becomes the conveyance force, and the leading end can be abutted against the sheet leading end stopper 11. As a result, it is possible to improve the consistency in the sheet conveying direction, and it is not necessary to provide a special aligning device such as an aligning plate, which can contribute to downsizing of the device and reduction in product cost.

By repeating the above-described operations, a predetermined number of sheets to be subjected to the binding process are stacked on the alignment tray 8. The alignment operation of the predetermined number of final sheets is the same as the alignment operation of the other sheets. Has been changed.

For the sheets other than the predetermined number of the last sheets, the above-described alignment operation in the sheet width direction is performed twice. That is, when aligning the sheet P in the sheet width direction, after the alignment plate 26 is moved from the standby position to the predetermined alignment position, the alignment plate 26 is returned to the opening direction once, and then the alignment plate 26 is again aligned in the predetermined alignment position. It has been moved to the position. By performing the alignment operation of the alignment plate 26 twice, the alignment of the sheet P can be further improved.

On the other hand, the last sheet is
After being discharged upward, the alignment plate 26 performs the alignment operation four times. Thus, before the sheet bundle on the alignment tray 8 is bound by the staple device 32, the alignment of the sheet bundle in the width direction can be finally ensured, and the reliability of the apparatus can be improved.

In this embodiment, the number of normal alignment operations (P) is set to two, and the number of alignment operations (Q) after the last sheet is discharged is set to four. There is no limitation, and any material that satisfies (P) <(Q) may be used.

The above is the description of the alignment operation of the sheet P on which an image has been formed.

Next, the binding process of the sheet bundle stacked on the alignment tray 8 by the above-described series of alignment operations will be described.

When a predetermined number of sheets to be subjected to the binding process are discharged onto the alignment tray 8 and the above-described alignment operation is completed, the upper bundle transport roller 14 shown in FIG. 7 operates the bundle transport roller solenoid 43 (FIG. 8). 7 moves in the direction of the alignment tray 8 (the direction of the arrow A in FIG. 7), and pinches the sheet bundle P together with the bundle conveyance lower roller 16.

Next, the sheet leading end stopper 11 is moved by the operation of the stopper solenoid 52 (FIG. 8).
Is rotated in the direction of arrow B about the rotation center axis 11a of
Release the abutting sheet tip. In addition, the curl press lever 18 which has been in contact with the uppermost sheet P by its own weight is used.
Is displaced to a position separated from the sheet P when the curl holding lever solenoid 48 is turned on. Thereafter, at a predetermined timing, the bundle transport upper and lower rollers 14 and 16 are driven by the bundle transport motor 55 (FIG. 8) to start rotating, and the sheet bundle P
Are bundled and conveyed toward the staple 32 side (the direction of arrow C in FIG. 7).

The transport speed V2 during the transport of the sheet bundle P
The rotation speed of the bundle transport motor 55 (FIG. 8) is set so that the transport speed is lower than the transport speed V1 when the sheet P is transported onto the alignment tray 8. This is performed in order to prevent misalignment during conveyance of the sheet bundle P, that is, so-called bundle deviation. When the leading end of the sheet bundle P reaches a predetermined position, the upper roller 19 for discharging the bundle moves in the direction of arrow A in FIG.
The sheet bundle P is nipped together with the bundle discharge lower roller 21.

The bundle discharge speed of the pair of bundle discharge rollers 19 and 21 due to the rotation of the bundle discharge motor 56 (FIG. 8) is equal to the bundle transfer speed of the pair of bundle transfer rollers 14 and 16; In a relationship. Therefore, the sheet bundle is conveyed to a predetermined position for performing the binding process without loosening and without shifting. When the bundle is conveyed to a predetermined position, the bundle discharge roller pair 19 and 21 and the bundle conveyance roller pair 1
The rotation of 4 and 16 is stopped, and the conveyance of the sheet bundle is stopped.
When the conveyance is stopped, the stapling device 32 driven by the stapler driving device 57 (FIG. 8) starts the sheet binding process. Here, a case where two binding processes are performed on the sheet bundle P will be described as an example.

The sheet bundle is first stapled at one end. Thereafter, the sheet bundle is again transferred to the bundle transport roller pair 14, 15
The bundle is conveyed by the pair of bundle discharge rollers 19 and 21 and 2
The sheet is conveyed to the staple position of the location. After stopping the conveyance of the sheet bundle at that position, the second stapling is performed by the stapling device 32. Thus, the sheet bundle P is subjected to the binding processing at two places. The staple device 32 has a known configuration and operation, and a description thereof will not be repeated.

When the stapling operation is completed, the sheet bundle P is transported again by the bundle transport roller pairs 14 and 15 and the bundle discharge roller pairs 19 and 21, and the trailing end of the sheet bundle is kicked out by the lower bundle discharge roller 21. Is discharged onto the discharge stacking tray 23.

As described above, the sheet bundle for which the sheet binding process is set is repeatedly aligned, bundle-conveyed, bound, and discharged, and is sequentially stacked on the discharge stacking tray 23.

As described in detail in this embodiment, the provision of the sheet rear end urging rib 9 for urging the rear end of the sheet discharged onto the alignment tray 8 in the sheet front end direction is simplified. With such a configuration, it is possible to enhance the consistency in the sheet conveyance direction, which is effective for reducing the size and cost of the apparatus.

(Second Embodiment) FIG. 9 is a diagram showing a second embodiment of the present invention which is different from the above-described first embodiment. In the same drawing, an urging member 40 is provided at the rear end side in the transport direction of the sheets P stacked on the alignment tray 8 and has a shape for lifting the rear end of the sheets P stacked on the alignment tray 8 upward. As the rear end lifting rib. The configurations of the sheet processing apparatus and the image forming apparatus other than the sheet rear end lifting rib 40 are the same as those of the first embodiment described above and have the same functions, and thus the description thereof is omitted.

By providing the sheet rear end lifting rib 40 having the above-described structure on the sheet rear end side of the alignment tray 8, the sheet P discharged from the discharge roller pair 5 is moved backward similarly to the sheet rear end urging rib 9 described above. The rear end portion of the sheet P is lifted by the inclined surface 40a, which is an urging surface, as compared with the front end portion against the force of the sheet P shifting backward. Therefore, the sheet P is prevented from moving in the direction opposite to the conveyance direction due to the sheet stiffness and the resistance due to the inclination of the sheet rear end lifting rib 40. Thereby, the sheet P is urged in the direction of the sheet leading end stopper 11, so that the consistency of the sheet P is improved.

Although the present invention has been described in detail above, the sheet rear end urging rib 9 and the sheet rear end as the urging members described in the first and second embodiments have been described. The lifting rib 40 may be formed integrally with the alignment tray 8.

The inclined surface 9a and the inclined surface 40a as the urging surfaces of the urging member described in the present embodiment have a substantially straight cross-sectional shape, but these inclined surfaces are curved. It does not matter.

By performing the above-described configuration and control of the sheet processing apparatus, the rear end of the sheet discharged onto the alignment tray 8 can be urged toward the sheet front end stopper 11 for adjusting the sheet conveying direction with a simple configuration. As a result, the consistency in the sheet conveying direction can be improved.

Conventionally, in the sheet processing apparatus, the alignment tray is inclined to the discharge roller side or the opposite side with respect to the horizontal plane to align the sheets using gravity, but the alignment tray is inclined. This has led to an increase in the size of the sheet processing apparatus, particularly in the height direction.

In the present invention, since the rear end of the sheet can be urged toward the front end of the sheet with a simple configuration, the alignment tray 8 can be provided in a substantially horizontal state as described in the embodiment. This makes it possible to reduce the size of the sheet processing apparatus in the height direction. Even if the sheet processing apparatus is disposed below the image forming apparatus as in the present embodiment, the operability of the image forming apparatus itself is not reduced, and the space is saved. A low-cost sheet processing apparatus can be provided.

[0101]

As described above, in the configuration of the sheet processing apparatus, by providing the urging member for urging the sheet toward the reference member, the trailing end of the sheet discharged onto the sheet stacking means can be adjusted. It is possible to urge the sheet in the direction of the abutting reference member that aligns the conveyance direction with a simple configuration, and it is possible to enhance the consistency in the sheet conveyance direction.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional front view showing an example of an image forming apparatus main body including a sheet processing apparatus according to the present invention.

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

FIG. 3 is a perspective view of a transport belt holder.

FIG. 4 is a side view showing a matching portion at the front end of the sheet.

FIG. 5 is a perspective view showing an alignment unit in the sheet width direction.

FIG. 6 is a side view of an urging member that urges the rear end of the sheet.

FIG. 7 is a side view of the leading end alignment unit showing a state of discharging a sheet bundle.

FIG. 8 is a block diagram according to control of the present invention.

FIG. 9 is a side view of an urging member according to a modification of the present invention.

[Explanation of symbols]

 Reference Signs List 5 discharge roller pair (discharge means) 8 alignment tray (sheet stacking means) 9 sheet rear end urging rib (urging member) 9a inclined surface of sheet rear end urging rib 10 conveyance belt (conveyance means) 11 sheet front end stopper ( Abutment reference member) 18 curl holding lever 26 alignment plate (width alignment means) 27, 29 roller (roller member) 28 side plate (width alignment means) 32 staple device (sheet binding means) 40 sheet rear end lifting rib (biasing member) 40a) Slope of the rear end lifting rib of the sheet

Continued on the front page. (72) Inventor Yasuyoshi Hayakawa 3-30-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Inc. (72) Inventor Tomoyuki Araki 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon stock Inside the company (72) Inventor Masayoshi Fukatsu 3-30-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Inc. (72) Inventor Atsushi Ogata 3-30-2 Shimomaruko, Ota-ku, Tokyo F-term in Canon Inc. (Reference) 3F054 AA01 AC01 BA02 BG08 BG11 BH05 BH07 DA01

Claims (18)

[Claims] A discharge unit that conveys and discharges a sheet on which an image is formed; a sheet stacking unit on which the sheets discharged by the discharge unit are stacked; and a sheet loaded from the discharge unit onto the sheet stacking unit. An abutting reference member provided on the leading end side of the sheet in the discharging direction and against which the leading end of the sheet discharged onto the sheet stacking unit is abutted; and a direction in which the sheet is discharged from the discharging unit onto the sheet stacking unit. And a biasing member provided on the rear end side of the sheet and biasing the sheet discharged from the discharge means in the direction of the abutting reference member. 2. The sheet processing apparatus according to claim 1, wherein said urging member is provided on said sheet stacking means. 3. The urging member has an urging surface with which the trailing end of the sheet discharged from the discharge means abuts, and the urging surface is inclined downward toward the abutting reference member. 3. The sheet processing apparatus according to claim 2, wherein the sheet processing apparatus is a surface. 4. The sheet processing apparatus according to claim 3, wherein a sheet stacking surface of said sheet stacking means is substantially horizontal. 5. The sheet processing apparatus according to claim 3, wherein the urging member is a plurality of ribs provided at intervals in a sheet width direction orthogonal to the sheet discharging direction. 6. The urging member has an urging surface on which the trailing end of the sheet discharged to the sheet stacking means is stacked, and the urging surface is inclined downward toward the abutting reference member. The sheet processing apparatus according to claim 1, wherein the sheet processing apparatus has a surface. 7. The sheet processing apparatus according to claim 6, wherein a side of the sheet stacking surface of the sheet stacking unit closer to the abutting reference member is substantially horizontal. 8. The sheet processing apparatus according to claim 1, further comprising a conveying unit that abuts a sheet discharged onto the sheet stacking unit by the discharging unit and conveys the sheet toward the abutting reference member. . 9. The sheet processing apparatus according to claim 8, wherein the conveying unit is a belt that rotates in a sheet conveying direction. 10. A width aligning means for aligning a sheet in a sheet width direction orthogonal to a sheet conveying direction after a sheet is discharged from said discharging means onto said sheet stacking means, and a leading end of said sheet comes into contact with said abutting reference member. The sheet processing apparatus according to claim 1, further comprising: 11. The width adjusting means is a plate member provided opposite to both end portions in the sheet width direction so as to contact an end portion in the sheet width direction, and both or any of the plate members is provided. The sheet processing apparatus according to claim 10, wherein one of the sheets is moved in a direction to sandwich the sheet to align the sheet in the sheet width direction. 12. A roller member that is rotatable in a sheet conveying direction and has a substantially conical shape on the side opposite to the plate member, on a surface of the plate member that is in contact with a sheet end. The sheet processing apparatus according to claim 10, wherein an upper side of a sheet is pressed during a sheet alignment operation by the plate member. 13. The sheet processing apparatus according to claim 10, wherein the aligning operation of the width aligning unit is performed every time a sheet is stacked on the sheet stacking unit. 14. The sheet processing apparatus according to claim 1, further comprising a sheet binding unit that performs a process of binding sheets stacked on the sheet stacking unit. 15. The apparatus according to claim 1, further comprising a leading end pressing member provided near the abutting reference member and configured to press a leading end of the sheet abutting on the abutting reference member toward the sheet stacking unit. Sheet processing equipment. 16. The sheet processing apparatus according to claim 1, wherein said urging member is provided integrally with said sheet stacking means. 17. An image forming apparatus comprising: the sheet processing apparatus according to claim 1; and image forming means for forming an image on a sheet based on image information. apparatus. 18. The sheet processing apparatus according to claim 17, wherein the sheet processing device is disposed below the image forming unit.
A sheet processing apparatus as described in the above.