JP2001322760A - Paper alignment device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To miniaturize a device provided with an alignment device and to reduce the cost. SOLUTION: This paper sheet alignment device is provided with a paper sheet rear end press means having a staple tray 71 for stacking entered paper sheets P and a change-over gate 53, and pressing the floating of the rear end part caused by curl of the paper sheet P entered in the staple tray 71 by the change-over gate 53; and a mobile alignment means having a rear end plate 72 being movable in the front/rear direction of the paper entering direction, and pushing the rear end of the paper sheet P entered in the staple tray 71 by the rear end plate 72 so as to align the paper sheet P in the front/rear direction of the entering direction of the paper sheet P.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet aligning apparatus provided in, for example, a digital multifunction peripheral or an image forming apparatus, for aligning a sheet on which an image is printed, for example, in post-processing such as staples.

[0002]

2. Description of the Related Art Conventionally, for example, a copying machine as an image forming apparatus has been disclosed in Japanese Patent Application Laid-Open Nos. 2-144370 and 10-177282. There is a printer having a paper post-processing device for performing stapling as post-processing. This sheet post-processing apparatus is provided with a sheet aligning apparatus that aligns sheets that have entered the sheet post-processing apparatus after printing before performing stapling processing.

On the other hand, a sheet on which an image has been printed by the image forming apparatus has passed through a fixing device (heat roller) for heating and pressing the toner image onto the sheet, and thus tends to curl. Therefore, simply inserting such a sheet into the aligning device usually makes alignment difficult.

Therefore, conventionally, a decolor for removing the curl of the sheet is provided between the fixing device of the image forming apparatus and the sheet aligning device. For example, as shown in FIG. 13A, the decolorer 201 includes two small-diameter driven rollers 203 made of rubber or plastic on the outer periphery of a large-diameter drive roller 202 made of rubber, and The curl is corrected by the driving roller 202 and the driven roller 203 to remove the curl.
04b. In another example, FIG.
As shown in (b), the decolorer 211 has a configuration including a driving roller 212 made of rubber and a driven roller 213 made of, for example, sponge pressed against the driving roller 212.

[0005]

However, the above-mentioned decolors 201 and 211 are expensive and require delicate adjustment of the pressing force, and are not easy to handle.

The height and direction of the curl generated in the paper vary depending on the paper manufacturing method, the paper cutting direction (so-called vertical and horizontal eyes), the type of the paper, the thickness of the paper, the moisture absorption of the paper, and the like. For this reason, the above decolor 201,
In the case of 211, it is necessary to make very complicated settings according to the above-mentioned conditions, but if this is not performed, it is difficult to sufficiently remove the curl of the sheet. In an extreme case, as shown by the decolor 211 in FIG. 14, for example, the reverse curl of the paper 204a generated in the fixing device becomes a larger curl (paper 204a ′) due to the processing by the decolor 211, and the alignment is performed. A misalignment has occurred in the device.

Further, the provision of the above decolorizers 201 and 211 leads to an increase in the size of the apparatus.

Therefore, according to the present invention, it is possible to reliably align sheets with a simple configuration without using a curl straightening device (decolors 201, 211), and to reduce the size and the size of the device provided with the aligning device. It is an object of the present invention to provide a sheet aligning device that can reduce costs.

[0009]

In order to solve the above-mentioned problems, a sheet aligning apparatus according to the present invention has a sheet stacking section for stacking incoming sheets, and a sheet rear end pressing member. A paper rear end pressing means for pressing the rising of the rear end of the paper entering the paper stacking section due to the curl of the paper by the paper rear end pressing member, and a movable alignment member movable in the front-rear direction in the paper input direction. And a movable aligning means for pushing the rear end of the sheet inserted into the sheet stacking section by the movable alignment member to align the sheet in the front-rear direction in the sheet input direction.

[0010] According to the above arrangement, the paper trailing edge pressing member suppresses the rising of the trailing edge caused by the curl of the paper entering the paper stacking section, and the movable alignment member pushes the trailing edge of the paper to hold the paper. Align in the front-back direction of the paper entry direction.

Therefore, when post-processing such as stapling is performed after the paper is aligned, even if the paper is curled through a fixing device, for example, the curled paper can be directly aligned.

This eliminates the need for expensive decoloring to correct the curl of the sheet, enables the sheet to be reliably aligned with a simple and inexpensive configuration, and provides a sheet post-processing apparatus having an aligning device and an image forming apparatus. An increase in the size of the forming apparatus and the like can be avoided.

In the above-described paper aligning apparatus, the paper trailing edge pressing member is configured such that, when the movable aligning member performs an alignment operation, the paper trailing edge pressing surface is located below the upper end of the movable aligning member. Along with
It may be configured to have a notch for avoiding collision with the movable alignment member that performs the sheet alignment operation.

According to the above configuration, the paper trailing edge pressing position for performing the sheet trailing edge pressing operation of the sheet trailing edge pressing member is set to an appropriate position without being restricted by the height of the movable alignment member. be able to. Further, in a state in which the paper rear end pressing member is disposed at the paper rear end pressing position and the movable alignment member is aligned, collision between the paper rear end pressing member and the movable alignment member can be avoided, and both can be simultaneously operated. Become.
Thus, an appropriate sheet aligning operation by the sheet trailing end pressing member and the movable alignment member can be performed.

In the above-described sheet aligning apparatus, the upper end of the movable aligning member is engaged with a rear end of the sheet that has entered the sheet stacking section and is lifted by the curl of the sheet, thereby preventing the sheet from rising further. A configuration in which a rear end locking portion is formed may be employed.

According to the above arrangement, the rear end portion of the paper is locked by the rear end locking portion of the movable alignment member.
It is possible to reliably prevent the rear end of the curled sheet from rising during the alignment operation. Thereby, a better alignment operation by the movable alignment member can be performed.

In the above-described paper aligning apparatus, the paper trailing edge pressing member may have a paper trailing edge pressing position in which the paper trailing edge pressing surface is located below the upper end of the movable aligning member when the movable aligning member performs an aligning operation. And a notch for avoiding collision with the movable alignment member that performs the sheet alignment operation, and the upper end of the movable alignment member has A paper trailing edge engaging portion is formed to engage with the trailing edge raised by the curl and prevent further lifting, and after the paper trailing edge pressing member is disposed at the paper trailing edge pressing position, the movable alignment is performed. A configuration may be provided that includes a control unit that controls the paper trailing end pressing unit and the movable alignment unit so that the alignment operation by the members is performed.

According to the above arrangement, at the time of the aligning operation by the movable alignment member, first, the paper rear end pressing member is disposed at the paper rear end pressing position. As a result, the trailing edge of the paper that has entered the paper stacking section, which has been lifted by the curl, is pressed down. Thereafter, an alignment operation is performed by the movable alignment member. At this time, the rear end portion of the sheet is pressed by the sheet rear end pressing member and is located below the upper end portion of the movable alignment member. And locked. Therefore, even if the paper is curled, the paper can be transferred from the paper trailing end pressing member to the movable alignment member, and the paper can be reliably aligned by the movable alignment member.

In the above sheet aligning device, the movable aligning member can be held in a rising state at the time of performing the aligning operation, and in a falling state in which the movable aligning member has fallen forward from the rising state in the sheet feeding direction. The movable aligning means holds the movable aligning member in the collapsed state when the aligning operation of the received sheet is completed, and drives the movable aligning member so that the rear end of the aligned sheet is pressed down by the upper end thereof. The configuration may be as follows.

According to the above arrangement, the movable aligning member is held in a collapsed state when the aligning operation of one sheet has been completed, and the upper end of the movable aligning member holds the rear end of the aligned sheet. Hold down.

Thus, it is possible to prevent the next sheet that has entered the sheet stacking section from colliding with the movable alignment member, and the rear end of the sheet once aligned rises again, and the next sheet is aligned with the sheet stacking section. The paper entering the paper can be prevented from colliding with the paper, or entering between the paper and the paper below it, and the order of pages being switched can be prevented.

In the above-described sheet aligning apparatus, the sheet trailing edge pressing member may be constituted by a switching member for switching a sheet input direction between the direction of the sheet stacking section and the other direction.

According to the above configuration, since the sheet trailing edge pressing member is also used as the switching member, an independent sheet trailing edge pressing member is provided to suppress an increase in the number of components and a situation in which control is complicated. Can be.

[0024]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIGS. The image forming apparatus
As shown in FIG. 2, an image forming apparatus main body 1 and a paper stack 2 are provided. The image forming apparatus main body 1 includes a document reading unit 3, a paper post-processing device 4, A tray 5, an image forming unit 6, and a paper feeding unit 7 are provided.

As shown in FIG. 3, the document reading section 3 has a document table 11 made of transparent glass or the like on the upper surface, and a scanner optical system 12 below the document table 11. The scanner optical system 12 includes an exposure light source 13, a plurality of reflecting mirrors 14, an imaging lens 15, and a CCD 16.

The exposure light source 13 irradiates a document placed on the document table 11 with light. The reflected light from the original is passed through an image forming lens 15 by a reflecting mirror 14 to a CCD
(Photoelectric conversion element) 16.

As shown in FIG. 3, the image forming section 6 has a photosensitive member 17 which is formed in a drum shape and rotates in the direction of an arrow. In the direction of the arrow around the photoreceptor 17,
Developing device 18, transfer charger 19, cleaning device (not shown), static eliminator 20, main charger 21, and laser scanning unit (hereinafter referred to as LSU 22)
22.

The document image data read by the CCD 16 is supplied to the LSU 22 after image processing. The LSU 22 irradiates the document image data as laser light onto the surface of the photoconductor 17 to form an electrostatic latent image.
The developing device 18 develops the electrostatic latent image into a visible image using toner. The transfer charger 19 develops the photoconductor 1
The toner image formed on the surface of the sheet 7 is transferred to the sheet P. The cleaning device removes residual toner on the surface of the photoconductor 17. The charge removing device 20 removes residual charges on the surface of the photoconductor 17. The main charger 21 charges the photoconductor 17 to a predetermined potential.

The paper supply section 7 has a paper cassette 31 containing paper P. At the leading end position of the paper cassette 31 in the paper output direction, an intake roller 32 for outputting the paper P and a paper separation roller 33 are provided.
The sheet separating roller 33 includes a roller that rotates in one direction and a roller that rotates in the reverse direction, and prevents double feeding of the sheet P. Note that, instead of this configuration, a configuration including a roller and a friction sheet member may be used.

As a paper transport path, a paper output path 34 on the cassette side is provided in the paper supply unit 7. In the case where the sheet P flows from the upstream side to the downstream side in the sheet transport path, the sheet separating roller 33 is provided at an upstream end of the cassette side sheet output path 34. The image forming unit 6 includes a manual paper feed path 35 and a main transport path 3 as a paper transport path.
6, a reverse transport path 37 and a paper discharge transport path 38 are provided,
The sheet post-processing device 4 is provided with a post-processing conveyance path 39.

At the upstream end of the manual paper feed path 35, a paper separating roller 40 is provided, and at this position, a manual paper feed tray 41 and a call-in roller 42 are provided.

The paper output path 34 on the cassette side and the manual paper supply path 35
And one end of the reversing conveyance path 37 are joined and connected to the upstream end of the main conveyance path 36. The main transport path 36 extends upward, merges with the other end of the reverse transport path 37 near the downstream end, and further branches downstream into a paper discharge transport path 38 and a post-processing transport path 39. I have.

A registration roller 43 is provided at an upstream end of the main conveyance path 36, and a pre-registration detection switch (not shown) for detecting passage of a sheet is provided at a position upstream of the registration roller 43. I have. In the image forming apparatus, the registration roller 43 performs alignment between the toner image on the photoconductor 17 and the paper P based on the detection signal of the pre-registration detection switch.

The transfer charger 19 in the main transport path 36
A fixing device 44 for heating and pressing the toner image on the sheet P is provided at a downstream position of the fixing device 44. This fixing device 44
Has a pair of fixing rollers and a fixing paper detection switch (not shown) for detecting the passage of a sheet through the fixing rollers.

At the downstream end of the paper discharge conveyance path 38, the paper P
A paper discharge roller 45 for discharging the paper to the main body tray 5 is provided.
The discharge roller 45 is located upstream of the discharge roller 45.
Is provided with a paper discharge detection switch (not shown) for detecting the passage of the paper in the.

Further, a paper discharge conveyance path 38 and a post-processing conveyance path 39
A switching gate 46 for switching the traveling direction of the sheet P to any one of these directions is provided at the branching point.

The post-processing transport path 39 guides the sheet P to the sheet post-processing device 4, as shown in FIG. A plurality of transport rollers 47 are provided at an intermediate position of the post-processing transport path 39, and a paper discharge roller 48 is provided at a downstream end. In addition, at the position on the upstream side of the paper discharge roller 48,
A paper detection switch 49 for detecting paper input to the paper post-processing device 4 is provided.

The sheet post-processing apparatus 4 has an escape transport path 51 serving as a non-post-processing transport path at an upper position on the downstream side of the discharge roller 48, and has a post-processing section 52 at a lower position. I have. The escape transport path 51 and the post-processing section 52
A switching gate (paper trailing edge pressing member, paper trailing edge pressing means) 53 for switching the traveling direction of the paper P to one of these directions is provided at the branch position.

The escape transport path 51 is used to discharge a sheet of paper P, such as special paper or small size paper, for which stapling is prohibited, or to discharge a large amount of paper P not to be stapled. This escape transport path 5
When 1 is selected, the switching gate 53 is switched to the state b shown by the two-dot chain line.

On the other hand, the post-processing section 52 is used for performing post-processing, that is, stapling, and sorting sheets P by offsetting the tray. When the post-processing section 52 is selected, the switching gate 53 is switched to the state a indicated by the solid line.

A first discharge path 54 and a second discharge path 55 of the sheet stack 2 are connected to the downstream end of the escape conveyance path 51, and the sheet stack 2 is connected to the downstream end of the post-processing section 52. Are connected. First discharge path 5
4 and a branch portion to the second discharge path 55, a switching gate 57 for switching the traveling direction of the paper P to one of these directions.
Is provided. The sheet P is guided to the first discharge path 54 when the switching gate 57 is in the state a indicated by the solid line, and is guided to the second discharge path 55 when the switch gate 57 is in the state b indicated by the two-dot chain line.

The first discharge path 54 has a conveying roller 58 and discharges the paper P to the first paper stack tray 59.
The second discharge path 55 has a paper discharge roller 60 and discharges the paper P to the second paper stack tray 61. The second paper stack tray 61 can move up and down, and can be offset and moved in a horizontal direction orthogonal to the paper discharge direction to the second paper stack tray 61.

Escape transport path 51 of sheet post-processing device 4
Is composed of general rubber rollers, and has a plurality of transport rollers 62 arranged in the transport direction of the paper P. These transport rollers 62 are arranged at a pitch shorter than the length in the transport direction of the minimum size paper P set to be capable of being discharged to the first paper stack tray 59 and the second paper stack tray 61. Escape transport path 51
Is composed of a roller pair in which rollers are pressed against the transport roller 62, an upper paper guide 63 and a lower paper guide 64. The lower paper guide 64 also functions as an upper paper guide in the post-processing unit 52.

In the post-processing section 52, a staple tray (sheet stacking section) 71 is disposed substantially horizontally. As shown in FIG. 4, the staple tray 71 has a rear end plate (movable alignment member, movable alignment means) 72, a side regulating plate 7
3. A tip stopper 74 and a stapler 75 are provided.

The rear end plate 72 is movable in the front-rear direction of the sheet conveyance direction. The rear end plate 72 pushes the rear edge of the sheet P that has entered the staple tray 71 and presses it against the front end stopper 74, thereby moving the sheet P back and forth. The alignment of the directional positions is performed.

The side regulating plate 73 is provided for the staple tray 7.
1 is provided on one end side in the paper width direction orthogonal to the paper transport direction. On the staple tray 71, a sheet side edge regulating portion 76 rising upward is formed on the side opposite to the one end side, facing the side regulating plate 73.
The side regulating plate 73 is movable in the sheet width direction orthogonal to the sheet conveying direction, and presses a side edge of the sheet P entered on the staple tray 71 and presses the sheet P against the sheet side edge regulating section 76, and The position of P in the paper width direction is aligned.

The tip stopper 74 is provided for the staple tray 7
1 is provided at the front end side in the sheet conveyance direction, and regulates and positions the alignment position of the sheets on the staple tray 71, that is, the front end position of the sheets to be stapled. The leading end stopper 74 is movable to a regulation position shown in FIG. 11 and a retracted position retreated downward from the upper surface of the staple tray 71.

As shown in FIG. 5, the rear end plate 72 has a plate shape extending in the sheet width direction orthogonal to the sheet conveyance direction. At the upper end of the rear end plate 72, the rear end of the sheet P protrudes forward in the sheet conveying direction, engages with the rear end of the curled sheet P, and prevents the rear end of the sheet P from rising further. A portion 72b is formed.

The rear end plate 72 is driven by a rear end plate driving mechanism (movable alignment means) 81 shown in FIG. The rear end plate drive mechanism 81 includes a base member 82, a slide member 83, a first helical gear 84,
A second helical gear 85 and a pressurizing spring 86 are provided. In addition, a stepping motor 87, a first belt 88, a second belt 8
9, a first pulley 90, a second pulley 91, and a third pulley 92. Further, as a driving unit for rotating the rear end plate 72, a solenoid 93, a solenoid arm 94,
Connecting arm 95, shaft arm 96, square shaft 97
And a return spring 99. In addition, an origin sensor 98 is provided.

The second belt 89 includes the staple tray 71
On the lower surface side, a second pulley 91 and a third pulley 92 are provided, and are arranged in the sheet transport direction. The base member 82 is connected to the second belt 89.

The second pulley 91 is disposed at a rear position in the sheet transport direction, and the third pulley 92 is disposed at a front position. The first pulley 90 and the second pulley 91 are provided on the same shaft and rotate integrally. The first pulley 90 is connected to a rotation shaft of the stepping motor 87 by a first belt 88. Therefore, the rotation of the stepping motor 87 causes the base member 82 to move in the front-rear direction in the sheet conveyance direction.

A square shaft 97 is disposed in the space between the opposing outward and return paths of the second belt 89 in the sheet transport direction. The rear end of the square shaft 97 is connected to a solenoid 93 via a shaft arm 96, a connection arm 95, and a solenoid arm 94. Accordingly, driven by the solenoid 93, the square shaft 97 rotates around its axis.

A first helical gear 84 is fitted to the square shaft 97 so as to be movable in the sheet conveying direction and to rotate integrally with the square shaft 97. The second bevel gear 85 meshes with the first bevel gear 84. Second bevel gear 8
Reference numeral 5 designates a paper width direction orthogonal to the paper conveyance direction as an axial direction, and is rotatably attached to the slide member 83 by its shaft 85a. A rear end plate 72 extending in the sheet width direction is fixed to the shaft 85a.

The slide member 83 is provided on the base member 82 and is movably provided in the sheet transport direction with respect to the base member 82 via a pressurizing spring 86. Therefore, the rotation of the stepping motor 87 causes the rear end plate 72 to move in the front-rear direction in the sheet conveyance direction.
The movable amount of the slide member 83 with respect to the base member 82 is determined by the length of the elongated hole 83b formed in the slide member 83.
Are restricted by a structure in which a pin 82a provided on the base member 82 is inserted.

In the rear end plate driving mechanism 81, the moving section including the rear end plate 72 moves rearward in the sheet conveying direction by rotating the stepping motor 87 clockwise. At this time, when the detection piece 83a provided at the rear end of the slide member 83 is detected by the origin sensor 98,
The rear end plate 72 has reached the home position,
The stepping motor 87 is stopped.

On the other hand, by rotating the stepping motor 87 counterclockwise by an arbitrary number of pulses, the rear end plate 72 can be moved to an arbitrary position corresponding to the number of pulses.

In this case, the rear end plate 72, that is, the slide member 83, usually moves integrally with the base member 82 by the compression repulsive force of the pressurizing spring 86. However, in the aligning operation by the rear end plate 72, the paper P may be pushed more than necessary due to variations in the paper size (normally, about ± 1 mm between lots). in this case,
If the paper P is larger than the specified size, the paper P may be damaged by a strong pushing force of the rear end plate 72. Therefore, in order to avoid such a situation, when an excessive pressing force is applied to the paper P, FIG.
As shown in FIG. 7, the rear end plate 72 is stopped by the compressing operation of the pressurizing spring 86. Thereby, the paper P can always be aligned with an appropriate pushing force, and the paper P is not damaged.

When the solenoid 93 is turned on to perform a retreating operation, the solenoid arm 94 rotates to pull the connecting arm 95, and the shaft arm 96, that is, the square shaft 9 is rotated.
7 rotates 90 degrees. As a result, the first helical gear 84 and the second helical gear 85 rotate 90 degrees, and the rear end plate 72 falls as shown in FIG. The tilt angle in this case can be appropriately set by adjusting the rotation angle of the square shaft 97 or the like. This operation is possible even when the moving part of the rear end plate driving mechanism 81 including the rear end plate 72 is moving.

On the other hand, when the solenoid 93 is turned off,
Return spring 99 connected to solenoid arm 94
, The square shaft 97 reversely rotates to the original position. As a result, the rear end plate 72 is raised.

In the moving part of the rear end plate driving mechanism 81, the second helical gear 85 is the second helical gear 8 shown in FIG.
It is also possible to use 5 '. This second bevel gear 8
5 'forms a gear by pin arrangement. In such a configuration, the second helical gear 85 'and the rear end plate 72 can be integrally formed by, for example, injection molding, and the manufacture is easy.

That is, in the injection molding of the second helical gear 85 shown in FIG. 5, when extracting the product from the mold, a method of extracting the product while rotating the product from the mold can be considered. Therefore, when the second helical gear 85 and the rear end plate 72 are integrally formed, the above-mentioned extraction cannot be performed, and the two cannot be integrally formed. On the other hand, in the second bevel gear 85 'in which the bevel gear has a pin arrangement, it is not necessary to remove the product by rotation, and the two can be integrally formed by injection molding.

The switching gate 53 shown in FIG. 2 also functions as a sheet rear end pressing member. The function is such that even if the sheet P entering the staple tray 71 is curled when passing through the fixing device 44, the leading end of the switching gate 53 can be aligned by the rear end plate 72. Presses the rear end of the sheet P.

For this purpose, the switching gate 53 has the shape shown in FIG. That is, the switching gate 53 is formed with a plurality of notches 53a on the tip end side.
By having 3a, the tip side has an uneven shape. Corresponding to this uneven shape, the rear end plate 72 has an uneven shape on the upper end side by forming a notch 72a on the upper end side.

Due to the above-mentioned shapes, the rear end plate 72 advances from the home position (the position shown by the solid line) to the alignment position (the position shown by the two-dot chain line) for aligning the paper P, as shown in FIG. At the same time, when the switching gate 53 is lowered to the paper trailing edge pressing position (state b shown in FIG. 2), the lower surface of the leading end of the switching gate 53 (paper trailing edge pressing surface 53b described later) is moved to the upper end of the rear end plate 72. It can be arranged at a position below the part.

Therefore, the depth of the notch 53a in the switching gate 53 is determined by the rear end plate 7 for aligning the sheet P.
The depth of the notch portion 72 a in the rear end plate 72 is set according to the advance position of the rear end plate 72.
The height is set in accordance with the height position of the front end of the rear end plate 72 that can appropriately press the rear end of the curled paper P so that the alignment can be performed more easily.

The switching gate 53 has a length corresponding to the length of the paper P entering the staple tray 71 in the paper width direction orthogonal to the paper entering direction, and the corners of the paper P are curled. It also exerts an appropriate pressing function on the bent paper P).

The above-mentioned switching gate 53 is provided in the state shown in FIG.
As shown in (b), the switching gate is driven by a switching gate driving mechanism (paper trailing edge pressing means) 104. In the switching gate drive mechanism 104, the switching gate 53 is
1, the shaft member 101 is provided with a solenoid connecting arm 102, and the solenoid connecting arm 102 is connected to the rod 100 of the solenoid 100.
a. The shaft member 101 is provided with a return spring 103. The return spring 103 is for returning the switching gate 53 to a state before the solenoid 100 is turned on, and is composed of a torsion coil spring.

When the solenoid 100 is turned on and the rod 100a retreats, the switching gate 53 presses the rear end of the sheet (the position indicated by the solid line in FIG. 10A, the state b).
And presses the rear end portion of the curled sheet P on the sheet rear end pressing surface 53b, which is the lower surface thereof. On the other hand, when the solenoid 100 is turned off, it is driven by the return spring 103 to rotate to the return position (the position indicated by the two-dot chain line in FIG. 10A, state a).

In this embodiment, the switching gate 53, the staple tray 71, the rear end plate 7
2. The sheet regulating device is constituted by the side regulating plate 73, the leading end stopper 74 and their driving mechanisms.

In the above configuration, the toner image formed on the photosensitive member 17 in the image forming section 6 shown in FIG.
For example, after being transferred to the sheet P supplied from the sheet cassette 31 by the transfer charger 19, the sheet is fixed to the sheet P by the fixing device 44.

The paper P is stapled (post-processing).
When the sorting is performed by the offset of the tray, or when a large amount of paper is discharged, the switching gate 46 shown in FIG. The state is switched to state a.
As a result, the paper P is transferred from the main transport path 36 to the post-processing transport path 3.
It is led to 9.

Next, when the above-mentioned paper P is a sheet for which stapling processing of special paper or small size paper is prohibited,
Alternatively, when the stapling process is not performed, the switching gate 53 is switched to the state b. As a result, the paper P is transferred to the escape conveyance path 51.
It is led to.

Thereafter, for example, the small-size paper P is guided to the switching gate 57 switched to the state a, and is discharged to the first paper stack tray 59. For example, a large amount of paper P is switched to the state b. The sheet is guided to the switching gate 57 and discharged to the second sheet stack tray 61.

On the other hand, the switching gate 53 is switched to the state a, for example, when a large-sized sheet P is stapled, and when the sheets P are sorted by tray offset. As a result, the sheet P enters the post-processing unit 52.

The sheets P entered into the post-processing section 52 are stacked on the staple tray 71 shown in FIG. At this time, the leading end stopper 74 has risen to the regulation position shown in the figure, and every time the paper P enters, the rear end plate 72 advances from the retracted position to the alignment position corresponding to the paper size and the paper P The paper P is aligned in the paper transport direction by pressing the rear end and pressing the front end of the paper P against the front end stopper 74. Similarly, each time the sheet P enters, the side regulating plate 73 advances from the retracted position to an alignment position corresponding to the sheet size, and pushes one side edge of the sheet P to push the other side edge of the sheet P. Is pressed against the sheet side edge regulating portion 76 to align the sheet P in the width direction orthogonal to the sheet conveying direction.

The rear end plate 72 and the side regulating plate 73 perform the above-mentioned alignment operation almost simultaneously, and after the alignment operation, are retracted to the respective retracted positions for receiving the next sheet P. Note that, when the above-described alignment operation is performed a plurality of times for one sheet of paper P, it is possible to reduce misalignment between the papers P and to perform more excellent alignment.

In the aligning operation by the rear end plate 72, first, as shown in FIG. 1A, the switching gate 53 for guiding the sheet P to the post-processing section 52 in the state a is operated by the post-processing section. 52, the solenoid 100 is turned on
By switching to N, the state is switched to the state b (the position where the trailing edge of the sheet is pressed). Thereafter, as shown in FIG. 1B, the rear end plate 72 advances from the retracted position to the matching position.

As described above, at the time of the aligning operation by the rear end plate 72, the switching gate 53 is first switched to the state b, so that the curl is caused by the fixing process in the fixing device 44 and the rear end of the sheet P is lifted. The part is a switching gate 5
3 is pressed down by the rear end pressing surface 53b. When the rear end plate 72 advances to the alignment position in this state,
The rear end plate 72 can reliably press the rear end of the sheet even on a curled sheet.

At this time, the rear end of the sheet P is pressed down by the switching gate 53 and is positioned below the sheet rear end locking portion 72b of the rear end plate 72. Locked at the stop 72b. Therefore,
Even if the sheet P is curled, the sheet P can be transferred from the switching gate 53 to the rear end plate 72, and the rear end plate 72 can surely align the sheet P.

Therefore, at the time of the stapling process, the variation of the leading end of each sheet P in the sheet bundle accumulated on the staple tray 71 is reduced, and the collapse of the sheet bundle is reduced.

As described above, when the paper P is aligned by the switching gate 53 and the rear end plate 72, the unevenness of the front end portion and the rear end plate 72 of the switching gate 53 causes
The front end of the switching gate 53 can be located below the upper end of the rear end plate 72. Thereby, the rear end plate 7
The switching gate 53 can provide the function of pressing the rear end of the curled sheet without reducing the height of the sheet 2, that is, without deteriorating the alignment function of the rear end plate 72.

After the completion of the alignment of the one sheet of paper P,
To accept the next sheet P, the solenoid 100 is turned off.
At F, the switching gate 53 returns to the state a. Further, as shown in FIG. 1C, the rear end plate 72 avoids interference with the next incoming paper P and presses the rear end of the paper P that has just been aligned. It retreats in the retreat direction and falls forward (paper rear end pressing position). In this state, the rear end plate 72 presses the rear end of the sheet P by the upper end portion, that is, the front convex portion 72b.

In the above state, the leading end of the sheet P is
2 until it has completely passed through the upper end. afterwards,
As shown in FIG. 1A, the rear end plate 72 rises and moves to the retracted position.

Thereafter, when the aligning operation of the last sheet P is completed, the stapling process is performed by the stapler 75 with the sheet bundle positioned by the rear end plate 72 and the side regulating plate 73.

When the stapling process is completed, the leading end stopper 74 is retracted to the retracted position, and the stapled sheet bundle is pushed out by the rear end plate 72 to a position where the sheet can be ejected by the ejection roller 60 shown in FIG. The paper is discharged onto the second paper stack tray 61 by the paper discharge rollers 60.

The sheet post-processing apparatus including the sheet aligning apparatus includes a control device (control means) shown in FIG.
This control device includes a CPU 121, a ROM 122, and an RA.
M123 is provided. The CPU 121 has a rear end plate 72.
A stepping motor 87 for moving the
A solenoid 93 for driving the rear end plate 72 between a falling state and a rising state, a solenoid 100 for switching the switching gate 53, a side regulating plate driving section 124, a leading end stopper driving section 125, a stapler 75, an origin sensor 98, and a paper detection switch 49 are provided. It is connected. CPU121
Is based on the program stored in the ROM 122 and the detection results of the origin sensor 98, the paper detection switch 49, etc., as described above,
2. Control the operations of the side regulating plate 73, the tip stopper 74, and the stapler 75.

Next, a series of operations in the case of performing the stapling process of the sheet post-processing device 4 will be described with reference to the flowchart of FIG.

In the sheet post-processing apparatus 4, when the stapling process in the post-processing section 52 is selected, first, the switching gate 53 is arranged in the state a (S1), and the rear end plate 72 is arranged in the retracted position. (S2).

In this state, when the sheet P enters the staple tray 71 (S3), as shown in FIG. 1A, the switching gate 53 is placed in the state b (S4). S
For example, the determination of the paper input in the
9 can be detected by the paper detection at 9 and the timing at the CPU 121.

Thereafter, the rear end of the sheet P is aligned by the rear end plate 72, and as shown in FIG.
The side edges of the paper P are aligned (S5).

Next, as shown in FIG. 1C, the rear end plate 72 is tilted to the paper rear end pressing position (S6), and the switching gate 53 is placed in the state a (S7).

Thereafter, it is determined whether or not one job (partial copy of a plurality of sheets and alignment of the plurality of sheets P) has been completed (S8). Here, the end of one job is determined, for example, from the image forming apparatus body 1 to the CPU 1.
This can be achieved by detecting information such as the number of copies transmitted to the printer 21 and detecting the number of sheets inserted based on the detection of sheets by the sheet detection switch 49.

If the result of this determination is that one job has not been completed, the next sheet P is awaited, and when the leading end of the next sheet P passes through the rear end plate 72 (S9), the rear end plate 72 Is moved to the retreat position (S10), and the process proceeds to S3 to repeat the subsequent processes. The determination as to whether or not the leading end of the sheet P has passed the rear end plate 72 in S9 can be made, for example, by detecting the sheet with the sheet detection switch 49 and measuring the time with the CPU 121.

On the other hand, if one job has been completed in S8, stapling is performed by the stapler 75 (S1).
1) The sheet bundle is discharged to the second sheet stack tray 61 (S12).

In the paper aligning apparatus of the present invention, when the movable alignment member has a long length of inserted paper, the movable alignment member may
In order to prevent the trailing edge of the sheet from rising, the sheet may be retracted in the opposite direction to the sheet entering direction to correct the trailing edge of the sheet due to curling, and then the sheet may be aligned at the sheet aligning position. .

According to the above configuration, it is possible to reliably correct the rear end curl of a long sheet to be discharged and to align the discharged sheet.

In the paper aligning apparatus according to the present invention, when the movable alignment member has a short length of the input paper, the movable alignment member is opposite to the paper discharge direction immediately after the paper is input to prevent the trailing edge of the paper from floating. It is also possible to adopt a configuration in which the sheet is retracted in the direction to correct the floating due to the curl of the trailing edge of the sheet, and thereafter, the sheet is aligned with the input side wall at the leading end position of the sheet in order to align the sheet.

According to the above configuration, when the input paper is of a small size, the rear end curl of the paper can be reliably corrected and the paper can be aligned.

In the above-described paper aligning apparatus, the movable aligning member can be tilted and raised by a pair of screw gears provided in the drive unit of the movable aligning member, and a shaft to which one of the screw gears is attached and whose angle change becomes clear. (For example, a polygon such as a quadrangle, a star, or a spline) may be employed.

According to the above configuration, the tilt of the movable alignment member can be controlled by the rotation of the shaft, and the drive source can be installed outside the unit.

[0101]

As described above, the sheet aligning apparatus of the present invention has a sheet stacking section for stacking the sheets that have been inserted, and a sheet rear end pressing member, and the sheet that has entered the sheet stacking section. And a movable alignment member movable in the front-rear direction of the paper input direction. And a movable alignment unit that pushes the rear end of the sheet that has entered the stacking unit to align the sheet in the front-rear direction of the sheet entry direction.

According to the above arrangement, when post-processing such as stapling is performed after the paper is aligned, even if the paper is curled through a fixing device, the curled paper is directly aligned. Can be.

As a result, an expensive decoloring for correcting the curl of the sheet is not required, the sheet can be surely aligned with a simple and inexpensive configuration, and a sheet post-processing apparatus having an aligning device and an image forming apparatus. An increase in the size of the forming apparatus and the like can be avoided.

In the above-described paper aligning apparatus, the paper trailing end pressing member is configured such that, when the movable aligning member performs the aligning operation, the paper trailing end pressing surface is located below the upper end of the movable aligning member. Along with
It may be configured to have a notch for avoiding collision with the movable alignment member that performs the sheet alignment operation.

According to the above configuration, the paper trailing edge pressing position for performing the sheet trailing edge pressing operation of the sheet trailing edge pressing member is set to an appropriate position without being restricted by the height of the movable alignment member. be able to. Further, in a state in which the paper rear end pressing member is disposed at the paper rear end pressing position and the movable alignment member is aligned, collision between the paper rear end pressing member and the movable alignment member can be avoided, and both can be simultaneously operated. Become.
Thus, an appropriate sheet aligning operation by the sheet trailing end pressing member and the movable alignment member can be performed.

In the above sheet aligning apparatus, the upper end of the movable aligning member is engaged with the rear end of the sheet that has entered the sheet stacking section by the curl of the sheet, and prevents the sheet from further floating. A configuration in which a rear end locking portion is formed may be employed.

According to the above configuration, the rear end of the paper is locked by the paper rear end locking portion of the movable alignment member, thereby reliably preventing the curled rear end of the paper from floating during the alignment operation. be able to. Thereby, a better alignment operation by the movable alignment member can be performed.

In the above-described paper aligning apparatus, the paper trailing edge pressing member may be such that the paper trailing edge pressing surface is located below the upper end of the movable aligning member when the movable aligning member performs the aligning operation. And a notch for avoiding collision with the movable alignment member that performs the sheet alignment operation, and the upper end of the movable alignment member has A paper trailing edge engaging portion is formed to engage with the trailing edge raised by the curl and prevent further lifting, and after the paper trailing edge pressing member is disposed at the paper trailing edge pressing position, movable alignment is performed. A configuration may be provided that includes a control unit that controls the paper trailing end pressing unit and the movable alignment unit so that the alignment operation by the members is performed.

According to the above arrangement, at the time of the aligning operation by the movable alignment member, first, the rear end portion raised by the curl of the sheet entering the sheet stacking section is pressed by the sheet rear end pressing member. An alignment operation is performed by the alignment member. At this time, the rear end portion of the sheet is pressed by the sheet rear end pressing member and is located below the upper end portion of the movable alignment member. And locked. Therefore, even if the paper is curled, the paper can be transferred from the paper trailing edge pressing member to the movable alignment member, and the paper can be reliably aligned by the movable alignment member.

In the above sheet aligning device, the movable aligning member can be held in a rising state when performing the aligning operation, and in a falling state in which the movable aligning member has fallen forward from the rising state in the sheet feeding direction. The movable aligning means holds the movable aligning member in the collapsed state when the aligning operation of the received sheet is completed, and drives the movable aligning member so that the rear end of the aligned sheet is pressed down by the upper end thereof. The configuration may be as follows.

According to the above configuration, it is possible to prevent the next sheet entering the sheet stacking section from colliding with the movable alignment member, and the rear end of the once aligned sheet rises again, and It is possible to prevent the next sheet entering the stacking section from colliding with the sheet, or from entering the sheet and the sheet below it, and changing the page order.

In the above-described sheet aligning apparatus, the sheet trailing edge pressing member may be constituted by a switching member for switching the sheet input direction between the direction of the sheet stacking section and the other direction.

According to the above configuration, since the paper trailing edge pressing member is also used as the switching member, an independent paper trailing edge pressing member is provided to suppress an increase in the number of components and a situation in which control is complicated. Can be.

[Brief description of the drawings]

FIG. 1A is an explanatory view showing a pressing operation of a rear end portion of a curled sheet by a switching gate in a sheet aligning apparatus according to an embodiment of the present invention; FIG.
FIG. 1A is an explanatory view showing a sheet aligning operation by a rear end plate after the operation of FIG. 1A, and FIG. 1C is a switching gate and a rear end plate when receiving the next sheet after the operation of FIG. FIG. 4 is an explanatory diagram showing the operation.

FIG. 2 is a schematic overall configuration diagram of an image forming apparatus including the sheet aligning device shown in FIG.

FIG. 3 is an overall configuration diagram showing the paper image forming apparatus main body shown in FIG. 2 in further detail;

FIG. 4 is a perspective view illustrating a configuration of a post-processing unit illustrated in FIG. 2;

FIG. 5 is a perspective view illustrating a configuration of a rear end plate driving mechanism illustrated in FIG. 4;

FIG. 6 is a perspective view showing an operation of alleviating damage to a sheet in a moving portion of the rear end plate driving mechanism shown in FIG. 5;

FIG. 7 is a perspective view showing an operation of setting the rear end plate in a falling state in the rear end plate driving mechanism shown in FIG. 5;

FIG. 8 is a perspective view showing a configuration of a moving unit in a rear end plate driving mechanism including a second helical gear different from the second helical gear shown in FIG. 5;

9 is a perspective view showing the shape of the switching gate shown in FIG. 2 and the rear end plate shown in FIG. 4, and the positional relationship between the two at the time of the alignment operation.

10 (a) is a front view showing a configuration for driving the switching gate shown in FIG. 9, and FIG. 10 (b) is a side view thereof.

FIG. 11 is a schematic block diagram illustrating a configuration of a control device that controls the operation of the sheet aligning device of the present embodiment.

FIG. 12 is a flowchart showing a control operation by the control device shown in FIG. 11;

13A is a perspective view showing an example of a decolorer for correcting curl of a sheet, and FIG.
It is a perspective view showing other examples of the decolor shown in (a).

FIG. 14 is a perspective view illustrating an example in which the curl of the sheet is further increased by the decoloring process illustrated in FIG.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Image forming apparatus main body part 2 Paper stack part 3 Document reading part 4 Paper post-processing device 6 Image forming part 17 Photoreceptor 44 Fixing device 49 Paper detection switch 51 Escape transport path 52 Post-processing part 53 Switching gate (paper rear end pressing member) 53a Notch section 53b Paper rear end pressing surface 71 Staple tray (paper stacking section) 72 Rear end plate (movable alignment member, movable alignment means) 72a Notch section 72b Paper rear end locking section 73 Side regulating plate 74 Leading end stopper 75 Stapler 76 Paper side edge regulating portion 81 Rear end plate drive mechanism (movable alignment member, movable alignment means) 87 Stepping motor 93 Solenoid 98 Origin sensor 100 Solenoid 103 Return spring 104 Switching gate drive mechanism (After paper) Edge holding means) 121 CPU (control means)

 ──────────────────────────────────────────────────の Continued on the front page (72) Inventor Yusuke Nagano 22-22, Nagaikecho, Abeno-ku, Osaka-shi, Osaka Inside Sharp Corporation (72) Inventor Koji Aoki 22-22, Nagaikecho, Abeno-ku, Osaka-shi, Osaka Incorporated (72) Inventor Takashi Makiura 22-22 Nagaikecho, Abeno-ku, Osaka City, Osaka F-term (reference) 3F054 AA01 AC01 BA01 BG03 BH02 BH05 BH07

Claims (6)

[Claims] A sheet stacking section for stacking the sheets that have been inserted, and a sheet trailing edge pressing member, which lifts the trailing end of the sheet that has entered the sheet stacking section due to curling of the sheet. A paper rear end pressing means for pressing by the end pressing member, and a movable alignment member movable in the front-back direction of the paper input direction;
A sheet aligning device comprising: a movable aligning unit that pushes a rear end portion of the sheet inserted into the sheet stacking unit by the movable alignment member to align the sheet in the front-rear direction of the sheet inserting direction. 2. The paper rear end pressing member is disposed at a paper rear end pressing position where a paper rear end pressing surface is located below an upper end portion of the movable alignment member during an alignment operation by the movable alignment member. 2. The sheet aligning apparatus according to claim 1, further comprising a notch for avoiding collision with the movable aligning member that performs the sheet aligning operation. 3. An upper end portion of the movable alignment member engages with a trailing end portion of the sheet that has entered the sheet stacking portion and is lifted by a curl of the sheet, and prevents the sheet from rising further. 2. The sheet aligning device according to claim 1, wherein the sheet aligning device is formed. 4. The paper rear end pressing member is disposed at a paper rear end pressing position where a paper rear end pressing surface is located below an upper end portion of the movable alignment member during an alignment operation by the movable alignment member. A notch portion for avoiding a collision with the movable alignment member performing the sheet alignment operation, and an upper end portion of the movable alignment member is lifted by the curl of the sheet entering the sheet stacking portion. Engage with the rear end,
A paper trailing edge locking portion for preventing further lifting is formed, and after the paper trailing edge pressing member is disposed at the paper trailing edge pressing position, the paper aligning operation by the movable alignment member is performed. 2. The sheet aligning apparatus according to claim 1, further comprising control means for controlling the rear end pressing means and the movable aligning means. 5. The movable aligning member is capable of holding a rising state when performing the aligning operation and a falling state in which the movable aligning member is tilted forward from the rising state in the sheet feeding direction. Holding the movable alignment member in the collapsed state when the alignment operation of one input sheet is completed,
The sheet aligning apparatus according to any one of claims 1 to 4, wherein the upper end drives the rear end of the aligned sheet so as to press it. 6. The paper trailing edge pressing member according to claim 1, wherein the paper trailing end pressing member comprises a switching member for switching a paper feeding direction between the direction of the paper stacking section and the other direction. A sheet aligning device according to any one of the above.