JP2000044109A - Paper sheet post-processor and image forming device equipped with the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the slid-falling of a transfer paper bundle even if a transfer paper bundle made of large sheets of transfer paper is stacked on a transfer paper bundle made of small transfer paper and stapled transfer paper bundles made of small sheets of transfer paper are stacked in tiers. SOLUTION: Plural sheets of transfer paper ejected from an image forming section are temporality housed. Transfer paper bundles reaching a specified number are ejected to the outside by a middle tray 341, the transfer paper bundles ejected from the middle tray 342 are sequentially stacked by a stack tray 382, the transfer paper bundles stacked on the stack tray 381 are shifted alternately in opposite sorting directions by specified shifting amounts and then sorted by a sorting means 343, and if each sheet of the transfer paper has a first specified size, then the transfer paper bundles are sorted by a specified first shifting amount. On the other hand, if each sheet of the transfer paper has a second size smaller than the first size, then the transfer paper bundles are sorted by a second shifting amount larger than the first shifting amount. For controlling this process, a control means is provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet post-processing apparatus for post-processing transfer paper discharged from an image forming apparatus such as a copying machine or a printer, and an image forming apparatus provided with the sheet post-processing apparatus.

[0002]

2. Description of the Related Art Conventionally, as a paper post-processing device, a transfer paper bundle consisting of a plurality of transfer papers, to which an image is copied (transferred) by an image forming apparatus such as a copying machine and discharged outside, is temporarily stored. An intermediate tray, a sheet processing unit for performing predetermined sheet processing such as stapling on the transfer sheet bundle on the intermediate tray, and a stack tray for sequentially collecting the transfer sheet bundle discharged from the intermediate tray There is.

In such a sheet post-processing apparatus, when a predetermined number of transfer sheets constituting a set of transfer sheet bundles are discharged from an image forming apparatus such as a copying machine onto an intermediate tray, the transfer sheet bundle is formed. Then, the sheet processing is performed, and the transfer sheet bundle subjected to the sheet processing is discharged from the intermediate tray and sequentially accumulated on the stack tray.

In this case, if the sheet processing is staple processing, even if each transfer sheet bundle is stacked at the same position on the stack tray, the separation of the transfer sheet bundle does not become unclear. In the case of (1) or when no paper processing is performed, if the transfer paper bundles are accumulated at the same position on the stack tray, it becomes difficult to distinguish the breaks of the transfer paper bundles forming a set.

For this reason, the sheet post-processing apparatus is provided with means for sorting the transfer paper bundle. When the staple process is not performed, each time the transfer paper bundle is discharged from the intermediate tray, the transfer paper bundle is orthogonal to the discharge direction. The sheets are alternately shifted by a predetermined shift amount in the direction and sorted, and are stacked on the stack tray in the sorted state. The sorting is performed with a constant shift amount regardless of the size of the transfer paper.

[0006]

By the way, in the above-mentioned conventional paper post-processing apparatus, as shown in FIG. 8A, a small size (for example, B
5 size paper a transfer paper stack consisting of the transfer paper size), large size on a plurality of sets of the transfer paper stack P ₁ having undergone stapling process (e.g., a plurality of sets consisting of the transfer paper of B4 size size) which may be integrated on top of the transfer paper stack P _2.

In this case, since the thickness of the stapled portion of the lower transfer paper bundle P ₁ becomes thicker due to the presence of the staple S, the transfer paper bundle P ₁ becomes more inclined toward the upper stage. the transfer paper stack P ₂ of the upper slide down as indicated by some from being integrated in the upper part of the transfer paper stack P ₂ while its periphery is protruding from the transfer paper stack P ₁ of the lower arrow (slip off) Sometimes. Even if the stapling process to the transfer paper stack P ₁ of the lower has not been subjected, since the peripheral portion of the transfer paper stack P ₂ of the upper is to protrude from the transfer paper stack P ₁ of the lower, in an unstable state become integrated is that there is a fear that a part of the upper portion of the transfer paper stack P ₂ is slipping.

Further, as shown in FIG. 8 (b), a small transfer paper (e.g., B5-size size) by the transfer paper stack P ₁ having undergone stapling process a transfer paper stack consisting of the onto the stack tray when integrated, the thickness of the decorated with locations of the staple processing when the number of sets of the transfer paper stack P ₁ increases is thickened by the presence of staple S, the transfer paper stack P ₁ toward the upper inclines, it may transfer paper stack P ₁ of the upper stage slides down as indicated by an arrow.

Such a problem is caused by the fact that the stapled transfer paper bundle is alternately shifted in the reverse direction by a shift amount larger than the normal shift amount to sort the stapled transfer paper bundle. since the position is sufficiently spaced in the transfer paper stack P ₁ consisting of the transfer paper of a small size slope of is not generated, it is considered as resolvable.

[0010] However, since the shift amount of the transfer paper stack P ₁ consisting of the transfer paper of a small size when such increases, the shift amount becomes larger the transfer paper stack P ₂ consisting of the transfer paper of a large size, accordingly sheet post-processing apparatus as well as large, consisting of the transfer paper of a large size on the transfer paper stack P ₁ comprising a transfer sheet smaller size it is necessary to increase the dimension in the sorting direction of the intermediate tray and stack tray Te another problem that the shift amount is large is by integrated state of the transfer paper stack P ₂ when the integration of the transfer paper stack P ₂ becomes unstable occurs.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and even when a transfer paper bundle made up of large transfer papers is stacked on a transfer paper bundle made up of small transfer papers, the transfer paper can be transferred without increasing the size of the apparatus. Paper that can prevent the bundle from slipping down and can prevent the transfer paper bundle from slipping down without increasing the size of the apparatus even when a large number of stacked transfer paper bundles made of small stapled transfer papers are stacked. It is an object to provide an image forming apparatus provided with a post-processing device and a sheet post-processing device.

[0012]

In order to achieve the above object, according to the first aspect of the present invention, there is provided a stack tray for stacking a plurality of transfer paper bundles discharged from an image forming section, and a stack tray. Sorting means for shifting and sorting the transfer paper bundles accumulated on the tray by a predetermined shift amount, such that the shift amount increases when the size of the transfer paper is small, and decreases when the size of the transfer paper is large. Control means for controlling the sorting means so that the shift amount is changed in accordance with the size of the transfer paper.

According to the configuration of the sheet post-processing apparatus, when the size of the transfer sheet is large, the transfer sheet bundle is shifted and sorted by a small shift amount, while when the size of the transfer sheet is small, the transfer sheet bundle is Are shifted and sorted by a large shift amount. Accordingly, even when a transfer paper bundle made of a large transfer paper is stacked on a transfer paper bundle made of a small transfer paper, the lowermost transfer paper bundle made of a large transfer paper is the uppermost transfer paper made of a small transfer paper. Since the sheet comes into contact with both the bundle and the lower-shifted transfer paper bundle, the contact area is increased, and the slipping of the transfer paper bundle composed of large transfer paper is prevented. Even when a large number of stacked transfer paper bundles made of small staple transfer papers are stacked, the stapled portions are separated from each other so that the staples do not overlap each other. Does not occur, and the sliding of the upper transfer paper bundle is prevented.

According to a second aspect of the present invention, in the first aspect, the control means causes the transfer paper bundle to move to a predetermined first size when the size of the transfer paper is a predetermined first size. When the size of the transfer paper is the second size smaller than the first size, the transfer paper bundle is sorted by the second shift amount larger than the first shift amount. The present invention is characterized in that the sorting means is controlled.

According to the configuration of the sheet post-processing apparatus, when the size of the transfer paper is the first size, the transfer paper bundle is the first size.
When the size of the transfer paper is the second size smaller than the first size,
The transfer paper bundle is sorted by being shifted by a second shift amount larger than the first shift amount. Thereby, even when the transfer paper bundle made of the large transfer paper is stacked on the transfer paper bundle made of the small transfer paper, the sliding of the upper transfer paper bundle is prevented,
Even when a large number of stacked transfer paper bundles made of small transfer papers subjected to stapling are stacked, the upper transfer paper bundle is prevented from slipping off.

According to a third aspect of the present invention, in accordance with the first or second aspect, the control means determines a size of the transfer paper according to a result of the determination by the size determining means. Drive signal control means for controlling the driving of the sorting means.

According to the configuration of the sheet post-processing apparatus, the size of the transfer sheet discharged from the image forming apparatus is determined, and the driving of the sorting unit is controlled in accordance with the determination result. As a result, even when a large transfer paper bundle is stacked on a small transfer paper bundle, the upper transfer paper bundle is prevented from sliding down, and the small transfer paper made of stapled transfer paper is prevented. Even in the case of stacking only a plurality of bundles, the upper transfer paper bundle is prevented from sliding down.

According to a fourth aspect of the present invention, in the third aspect, the drive signal control means determines that the first shift amount is smaller than the first shift amount when the size of the transfer paper is the first size. A first drive signal output unit that drives the sorting unit so that the second shift amount is equal to the second shift amount when the size of the transfer sheet is the second size. 2 drive signal output means.

According to the configuration of the sheet post-processing apparatus, the sorting means is driven so that the shift amount is small when the size of the transfer sheet is large, and the shift amount is large when the size of the transfer sheet is small. The sorting means is driven as described above. As a result, even when a large transfer paper bundle is stacked on a small transfer paper bundle, the upper transfer paper bundle is prevented from sliding down, and the small transfer paper made of stapled transfer paper is prevented. Even in the case of stacking only a plurality of bundles, the upper transfer paper bundle is prevented from sliding down.

According to a fifth aspect of the present invention, in the invention according to any one of the second to fourth aspects, a transfer paper bundle made of the transfer paper of the second size is accumulated at a lower portion on the stack tray, The present invention is characterized in that the transfer paper bundle made of the first size transfer paper is stacked on the transfer paper bundle made of the second size transfer paper.

According to the configuration of the sheet post-processing apparatus, the second
The transfer paper bundle composed of the transfer papers having the sizes shown in FIG. 3 is sorted by a large shift amount, and the first transfer paper bundle is placed on the sorted transfer paper bundle.
Transfer paper bundles of transfer papers of the following sizes are stacked and stacked. Accordingly, even when the transfer paper bundle made of the large transfer paper is stacked on the transfer paper bundle made of the small transfer paper, the transfer paper bundle formed of the large transfer paper at the upper portion is prevented from slipping.

According to a sixth aspect of the present invention, there is provided an image forming section for transferring an image to a transfer sheet, a stack tray for stacking a transfer sheet bundle composed of a plurality of transfer sheets discharged from the image forming section, Sorting means for shifting and sorting the transfer paper bundle accumulated on the stack tray by a predetermined shift amount;
When the size of the transfer paper is small, the shift amount increases,
And control means for controlling the sorting means such that the shift amount is changed according to the size of the transfer paper so that the shift amount is reduced when the size of the transfer paper is large.

According to the configuration of the image forming apparatus, when the size of the transfer sheet is large, the transfer sheet bundle is shifted and sorted by a small shift amount, while when the size of the transfer sheet is small, the transfer sheet bundle is sorted. It is shifted and sorted by a large shift amount. Accordingly, even when a transfer paper bundle made of a large transfer paper is stacked on a transfer paper bundle made of a small transfer paper, the lowermost transfer paper bundle made of a large transfer paper is the uppermost transfer paper made of a small transfer paper. Since the sheet comes into contact with both the bundle and the lower-shifted transfer paper bundle, the contact area is increased, and the slipping of the transfer paper bundle composed of large transfer paper is prevented. Further, even when a large number of transfer paper bundles made of small transfer papers subjected to the stapling process are stacked in a large number,
Since the staple-processed portions are separated from each other so that the staples do not overlap each other, the inclination of the transfer paper bundle does not occur, and the upper transfer paper bundle is prevented from sliding down.

According to a seventh aspect of the present invention, based on the sixth aspect, the control means is configured to, when the size of the transfer paper is a predetermined first size, transfer the transfer paper bundle to a predetermined first size. When the size of the transfer paper is the second size smaller than the first size, the transfer paper bundle is sorted by the second shift amount larger than the first shift amount. The present invention is characterized in that the sorting means is controlled.

According to the configuration of the image forming apparatus, when the size of the transfer paper is the first size, the transfer paper bundle is shifted and sorted by the first shift amount, and the size of the transfer paper is changed to the first size. In the case of the second size smaller than the size, the transfer paper bundle is shifted and sorted by the second shift amount larger than the first shift amount. As a result, even when a large transfer paper bundle is stacked on a small transfer paper bundle, the upper transfer paper bundle is prevented from sliding down, and the small transfer paper made of stapled transfer paper is prevented. Even in the case of stacking only a plurality of bundles, the upper transfer paper bundle is prevented from sliding down.

The invention according to claim 8 is the invention according to claim 7, wherein the control means determines a size of the transfer paper, and the control means determines the size of the transfer sheet in accordance with a determination result of the size determination means. And a drive signal control means for controlling the driving of the sorting means.

According to the configuration of the image forming apparatus, the size of the transfer sheet discharged from the image forming apparatus is determined, and the driving of the sorting unit is controlled in accordance with the determination result. As a result, even when a large transfer paper bundle is stacked on a small transfer paper bundle, the upper transfer paper bundle is prevented from sliding down, and the small transfer paper made of stapled transfer paper is prevented. Even in the case of stacking only a plurality of bundles, the upper transfer paper bundle is prevented from sliding down.

According to a ninth aspect of the present invention, in accordance with the eighth aspect, the drive signal control means determines that the first shift amount is smaller than the first shift amount when the size of the transfer paper is the first size. A first drive signal output unit that drives the sorting unit so that the second shift amount is equal to the second shift amount when the size of the transfer sheet is the second size. 2 drive signal output means.

According to the configuration of the image forming apparatus, the sorting device is driven so that the shift amount is small when the size of the transfer paper is large, and is large when the size of the transfer paper is small. The sorting means is driven.
As a result, even when a large transfer paper bundle is stacked on a small transfer paper bundle, the upper transfer paper bundle is prevented from sliding down, and the small transfer paper made of stapled transfer paper is prevented. Even in the case of stacking only a plurality of bundles, the upper transfer paper bundle is prevented from sliding down.

The invention according to claim 10 is the invention according to claim 6
In any one of the first to ninth aspects, the transfer paper bundle made of the second size transfer paper is accumulated at a lower portion on the stack tray, and the transfer paper bundle made of the first size transfer paper is stored in the first size. It is characterized in that it is stacked on a transfer paper bundle made of transfer paper of size 2 and is stacked.

According to the configuration of the sheet post-processing apparatus, the second
The transfer paper bundle composed of the transfer papers having the sizes shown in FIG. 3 is sorted by a large shift amount, and the first transfer paper bundle is placed on the sorted transfer paper bundle.
Transfer paper bundles of transfer papers of the following sizes are stacked and stacked. Accordingly, even when the transfer paper bundle made of the large transfer paper is stacked on the transfer paper bundle made of the small transfer paper, the transfer paper bundle formed of the large transfer paper at the upper portion is prevented from slipping.

[0032]

FIG. 1 is a side view schematically showing an internal configuration of an image forming apparatus provided with a sheet post-processing apparatus according to an embodiment of the present invention. In FIG. 1, the image forming apparatus includes a copying machine 1 as an image forming unit, and a sheet post-processing device (finisher) 3 as a sheet post-processing unit disposed on the left side of the copying machine 1.

The copying machine 1 includes a main body 5, a document reading section 7 provided above the main body 5, and an automatic document feeding section 9 provided above the document reading section 7. I have. Main unit 5
Includes an original reading unit 51, an optical unit 52, an image forming unit 54 having a photosensitive drum 53, a fixing unit 55, and a transfer paper conveying unit 56. An operation panel 57 is provided at a position on the upper front side of the main body 5, and a transfer paper discharge unit 58 is provided below the document reading unit 51.

The original reading section 7 includes a first contact glass 71 mounted on the top of the main body section 5 and a second contact glass 72 disposed on the left of the first contact glass 71. I have. This first contact glass 71
The second contact glass 7 forms a stationary original reading area for reading an image by scanning a stationary original with a scanner 512 of the original reading unit 51, which will be described later.
Reference numeral 2 denotes a conveyed document reading area for reading an image by moving the document with respect to the scanner 512 which is stationary at that position.

The automatic document feeding section 9 includes a document placing section 91,
Document discharge section 92, paper feed roller 93, transport roller 94
And a document transport section 95 having
The original set in 1 is fed out by the paper feed roller 93 and transported one by one to the position of the second contact glass 72 one by one by the original transport unit 95, and the original image is placed below the second contact glass 72. Scanner 5 located
The document read by the image reading unit 12 and having the image read out is discharged to a document discharge unit 92. The read document image is stored in a memory 114 described later.

The original placing section 91 is provided with a pair of transport guide members 96 for transporting the placed original while regulating the position in the width direction (direction orthogonal to the transport direction). I have. In addition, the document placing section 91, a document width sensor S _W located upstream of the paper feed roller 93, the document passes the sensor S _D located downstream of the paper feed roller 93 is disposed. The document width sensor S _W is for detecting a width size of the document placed on the document placing portion 91,
For example, the position of the transport guide member 96 is detected. The document passing sensor _SD detects the passage of the document fed by the paper feed roller 93, and detects the leading edge position and the trailing edge position of each document each time the document is fed. It was done.

The automatic document feeder 9 is configured to be openable and closable with respect to the first contact glass 71 with the end on the depth side in the drawing as a rotation fulcrum. The configuration also serves as a presser for a document to be placed.

The document reading means 51 includes a guide rail 511 disposed in the left and right direction, and a scanner 512 as an image reading means disposed reciprocally in the left and right direction along the guide rail 511. . Scanner 512
A light source including LEDs or the like for illuminating the original surface, an image reading unit including a CCD or the like, a mirror for guiding the original image to the image reading unit, and the like are provided. Usually, a first contact glass 71 and a second contact glass 72 are provided. Is to wait at a home position, which is an intermediate position of.

That is, when an original is placed on the first contact glass 71 and the start button is turned on, the scanner 512 drives the drive motor (not shown) to move the original from the home position to the leading end position of the original. (The right end in the figure). Then, the scanner 512 scans the original surface by moving from the leading end position to the trailing end position (left end in the drawing) of the original with the light source turned on, and reads an image line by line. The read image is subjected to predetermined data processing, converted into a digital signal, and stored in a memory 114 described later. When the reading of the document image is completed, the scanner 512 turns off the light source and returns to the home position.

The scanner 512 is connected to the original placing section 91.
When the original is set and the start button is turned on, the drive motor (not shown) is driven to move from the home position to the position of the second contact glass 72 while the original is transported by the original transport unit 95. Being second
When the original image passes through the contact glass 72, the original image 1
Read every line. The read image is stored in the memory 114 in the same manner as described above. Scanner 5
At 12, the image returns to the home position after the image reading of all the originals set on the original placing portion 91 is completed.

The optical unit 52 exposes the original image read from the memory 114 to the photosensitive drum 53, and converts a modulation signal generated based on the image data into a laser beam and outputs the laser beam. And a reflection mirror for reflecting the laser light from the light emitting section toward the photosensitive drum 53.

The image forming section 54 is provided at the upper portion of the peripheral surface of the photosensitive drum 53, a developing section provided downstream of the charger, and a downstream section of the developing section. It has a cleaning unit and the like. The photoreceptor drum 53 is rotated in the direction of the arrow by the rotation of a drive motor (not shown), and an electrostatic area is formed at a position facing the charger. An electrostatic latent image is formed, and the electrostatic latent image is developed into a toner image at a position facing the developing unit. A transfer roller is disposed at a position facing the photosensitive drum 53. The photosensitive drum 53 on which the toner image is formed transfers the toner image to transfer paper at a position facing the transfer roller, and is provided with a cleaning unit. The toner remaining on the surface at the opposing position is removed. The transfer paper on which the toner image has been transferred is fixed to the fixing unit 55.
Is heated and fixed.

The transfer paper transport section 56 includes a plurality of paper feed cassettes 561 each containing a stack of transfer papers P having different sizes, and a paper feed roller 562 for drawing out the transfer paper P in the paper feed cassette 561 to the outside. The transfer paper drawn from the paper feed cassette 561 is guided to the photosensitive drum 53,
The transfer paper on which the toner image is formed on the photosensitive drum 53 is transferred to the paper post-processing device 3 or the transfer paper discharge unit 5 via the fixing unit 55.
8 is provided.

[0044] so that the transfer sheet sensor S _P on the downstream side position of the fixing unit 55 in the transfer sheet conveyance path 563 are disposed to count the number of copies. A bypass paper feed unit 564 is provided above the paper feed cassette 561. When transfer paper is set in the bypass paper feed unit 564, the transfer paper is sequentially fed out by the paper feed roller 565. It is conveyed to the photosensitive drum 53 side.

When only a part of the original placed on the first contact glass 71 or the original set on the original placing portion 91 is copied, the copied transfer paper is transferred to the transfer paper discharge portion 58. Is discharged. The transfer paper copied by selecting the sort mode or the group mode is supplied to the discharge port 59.
Is discharged to the sheet post-processing device 3 side. Here, the sort mode refers to a mode in which transfer sheets are aligned and discharged in the order of pages when a plurality of originals are copied in a plurality of copies, and the group mode refers to each page when a plurality of originals are copied in a plurality of copies. This is a mode in which the number of copies is output for each copy.

Therefore, in the sort mode, one set of transfer sheets is constituted by the number of transfer sheets equal to the number of originals, and in the group mode, one set of transfer sheets is formed by the number of transfer sheets equal to the number of copies. A bundle is formed. Therefore, in the case of the sort mode, the number of sets of the transfer sheet bundle is equal to the number of copies, and in the case of the group mode, the number of sets of the transfer sheet bundle is equal to the number of documents.

The operation panel 57 has a start button 571
And a size designation key 572 for designating a transfer paper size;
Various setting keys 5 such as a copy number setting key 573 including ten keys for setting the number of copies, a sheet processing setting key 574 for specifying staple processing, and a mode selection key for selecting one of the sort mode and the group mode.
75, and a display unit 576 for displaying settings such as the transfer paper size and the number of copies.

The paper post-processing device 3 is provided with a discharge port 5 of the copying machine 1.
9, a transfer entrance 32 into which the transfer paper discharged from the transfer paper 9 is introduced, and a transfer paper transport unit 32 that transports the transferred transfer paper to the downstream side.
And an intermediate tray portion 34 for temporarily storing a plurality of transfer papers carried in from the carry-in entrance 31 and discharging a predetermined number of transfer paper bundles to the outside, and a lower end portion of the intermediate tray portion 34. The paper processing section 37 provided, the stack tray section 38 for accumulating the transfer sheet bundle discharged (transferred) from the intermediate tray section 34, and the conveyance for discharging the transfer sheet bundle of the intermediate tray section 34 to the stack tray section 38. An outlet 39 is provided.

The transfer paper transport section 32 transports the transfer paper carried in from the carry-in entrance 31 to the intermediate tray section 34, and includes a common transport path 321 and a main transport path 322 branched from the common transport path 321 and a bypass. And a transport path 323. The common transport path 321 includes a transport roller pair 324 that transports the transfer paper loaded from the transport entrance 31 to the downstream side,
A direction switching valve 325 for transporting the transfer paper transported by the transport roller pair 324 to one of the main transport path 322 and the bypass transport path 323 is provided.

The direction switching valve 325 is switched by a solenoid (not shown) to one of a position indicated by a solid line and a position indicated by a chain line. Conveyance path 32
2, the transfer paper is fed to the bypass conveyance path 323 when it is switched to the position indicated by the chain line.

In the main transport path 322, four pairs of transport rollers 326, arranged in order from the upstream side to the downstream side,
327, 328, 329, and direction switching valves 330, 331, 332 disposed between each pair of transport rollers. Each of the direction switching valves 330, 331 and 332 is switched by a solenoid (not shown) to one of a position indicated by a solid line and a position indicated by a chain line. At that position, the sheet is discharged to the intermediate tray portion 34, and when the position is switched to the position indicated by the dashed line, the transfer sheet is further transported downstream.

In the bypass conveying path 323, the conveying rollers 3
33 are provided. The bypass conveyance path 323 is used when the sheet processing unit 37 performs the sheet processing on the transfer sheet bundle stored in the intermediate tray unit 34 or when the intermediate tray unit 3
This is selected while the transfer paper bundle No. 4 is being discharged to the stack tray section 38, and temporarily stores the transfer paper discharged from the copying machine 1 during the operation thereof. The stack of transfer sheets in the intermediate tray section 34 is
8, the transfer paper stored in the bypass conveyance path 323 is discharged to the intermediate tray unit 34.

The intermediate tray section 34 is inclined and disposed so that the upper side is located on the stack tray section 38 side and the lower end side is located on the copying machine 1 side. An intermediate tray (tray main body) 341 for temporarily storing transfer paper, a transfer unit 342 for discharging a transfer paper bundle formed of a predetermined number of transfer papers stored on the intermediate tray 341 to the outside, and an intermediate tray 341 And a sorting unit 343 for shifting (shifting) the transfer paper bundle stored in the printer 1 by a predetermined shift amount in the left-right direction (the width direction orthogonal to the transfer paper conveyance direction). A discharge path 40 is provided above the intermediate tray 34, and a discharge roller pair 41 is provided at the end of the discharge path 40.

FIG. 2 is a plan view of the intermediate tray section 34. That is, the conveying means 342 is bridged between the upper pulley 344 disposed at the upper end of the intermediate tray 341 and the lower pulley 345 disposed at the lower end thereof, and reaches the predetermined number of sheets. Intermediate tray 3
The stack of transfer paper bundles on the stack tray section 3
It has a transport belt 346 for discharging to the 8 side, and a transport belt drive motor 347 connected to the drive shaft of the lower pulley 345.

The transport belt 346 is provided at the center of the left belt 3 along the transfer paper transport direction (the direction of arrow A).
48 and a right belt 349. Each belt 34
8, 349 are arranged so as to surround the peripheral surface of the intermediate tray 341, and the portion existing on the surface side of the intermediate tray 341 is depressed in a vertical groove 350 formed on the surface of the intermediate tray 341. The portion that is provided and is present on the back side of the intermediate tray 341 is bridged over the tension roller 351 (FIG. 1).

The conveyor belt 346 has a hook-shaped receiving portion 352 for receiving the lower end surface of the transfer sheet at a position existing on the surface side of the intermediate tray 341.
The receiving portion 352 is rotatably driven by the conveyor belt drive motor 347 so as to move between a lower end position indicated by a solid line and an upper end position indicated by a chain line. That is, the receiving portion 352
When the transfer paper is discharged onto the intermediate tray 341, it is at the lower end position, which is the home position. When the transfer paper bundle on the intermediate tray 341 is discharged onto the stack tray 371, the lower end position is the home position. Will move to the position.

The sorting means 343 is disposed on the left side of the intermediate tray 341 in the direction of transfer of the transfer sheet, and is a long left side for shifting the transfer sheet bundle to the right side in the drawing with respect to the discharge direction. A width shifting member 353, left member moving means 354 for moving the left width shifting member 353 in the left-right direction (width direction),
An elongated right width shifting member 355 arranged on the right side of the intermediate tray 341 along the transfer paper transport direction and for shifting the transfer paper bundle to the left side in the drawing with respect to the discharge direction. Right member moving means 356 for moving the width shifting member 355 in the left-right direction (width direction).

The left width shifting member 353 has a support shaft 357 mounted vertically on the bottom face fitted in a left slide hole 358 formed in the intermediate tray 341 and extending in the left-right direction.
It is movable between the left end and the center.

The left member moving means 354 is a rack 35 on which the support shaft 357 of the left width shifting member 353 is mounted on the upper surface.
9 and the pinion 360 meshed with the rack 359
And a left member drive motor 3 for driving the pinion 360
61, the left member driving motor 361 rotates in both the forward and reverse directions so that the rack 359
As a result of the movement along 58, the left width shifting member 353 reciprocates between the left end side and the center side.

A left member sensor _SH is disposed on the left edge of the back side of the intermediate tray 341, and a left width shifting member 353 is provided.
Detects the end of the rack 359 when it moves to the home position which is the leftmost position, and the left width shifting member 3 is determined based on the home position.
The movement distance of 53 is managed.

The right width shifting member 355 has a support shaft 362 mounted upright on the bottom face fitted in a right slide hole 362 formed in the intermediate tray 341 and extending in the left-right direction.
It is movable between the right end and the center.

The right member moving means 356 is a rack 36 on which the support shaft 362 of the right width shifting member 355 is mounted on the upper surface.
4 and the pinion 365 meshed with the rack 364
And a right member drive motor 3 for driving the pinion 365
66, and the right member drive motor 366 rotates in both the forward and reverse directions, so that the rack 364 is moved to the right slide hole 3.
As a result of moving along 62, the right width shifting member 355 reciprocates between the right end side and the center side.

A right member sensor _SM is disposed on the right side edge of the back side of the intermediate tray 341, and a right width shifting member 355 is provided.
Detects the end of the rack 364 when it moves to the home position, which is the position on the rightmost side.
55 movement distances are managed.

The paper processing section 37 is provided with an intermediate tray 34.
A pair of staplers 371 and 37 at a predetermined interval
2 for stapling the edges of the transfer sheet bundle discharged onto the intermediate tray 341. Note that the staplers 371 and 372 are provided with drive motors 373 and 374, respectively, and one stapler 371 (or the other stapler 372) is used to perform stapling on one edge of the transfer paper bundle. When the stapling process is performed on two edges of the transfer paper bundle, both staplers 371 and 372 are used.

Returning to FIG. 1, the stack tray section 38 includes a stack tray (tray main body) 381 and a moving means 382 for reciprocating the stack tray 381 in the vertical direction (the direction of arrow B). The moving means 382 includes a moving belt 385 bridged over the upper roller 383 and the lower roller 384, and the moving belt 385
Moving belt drive motor 38 which is driven to rotate via 84
6 is provided.

[0066] Further, in the example the vicinity of the upper roller 383, a position sensor S _T for detecting whether the stack tray 381 is in the uppermost position, to detect the accumulation height of the transfer paper stack on the stack tray 381 integrated and height sensor S _S is disposed. The integrated height sensor S _S is formed of, for example, a light reflection type photo interrupter, and the position sensor S _T
Is composed of, for example, a light transmission type photo interrupter.

That is, when the transfer paper bundle is not discharged onto the stack tray 381,
1 rises to the uppermost position (initial position) and stack tray 3
So that the stack tray 381 is detected to be in the uppermost position by the light shielding plate attached to 81 blocks the optical path of the position sensor S _T.

[0068] Also, a moving belt drive motor 386 by a height sensor S _S integrated with the transfer paper stack is discharged onto the stack tray 381 detects that it is driven in a direction to lower the stack tray 381. Accordingly, the distance between the upper surface of the transfer sheet bundle on the stack tray 381 and the outlet 39 is substantially equal to the distance between the upper surface of the stack tray 381 and the outlet 39 when the transfer sheet bundle is not discharged. , So that the transfer sheet bundle is reliably discharged from the intermediate tray 341. Thus, the stack tray 381 so that the optical path of the position sensor S _T, which has been blocked by the light shielding plate is formed by lowering a result, the transfer paper stack is determined to be discharged onto the stack tray 381 Will be.

FIG. 3 is a block diagram showing a control configuration centering on the operation of the sheet post-processing apparatus 3 according to the present invention. In FIG. 1, a control unit 11 is provided on the copying machine 1 side, and performs a predetermined calculation or control process.
And a ROM 11 storing a predetermined processing program
1 and a RAM 112 for temporarily storing processing data. The control unit 13 is provided on the sheet post-processing device 3 side, and performs a predetermined calculation or control process.
PU 130, ROM 131 storing a predetermined processing program, and RAM temporarily storing processing data
132. These control units 11 and 13
Connected via respective input / output units 113 and 133,
By performing the bidirectional communication, the operations of the copying machine 1 and the sheet post-processing device 3 are controlled.

[0070] Further, the CPU110 of the control unit 11, a start button 571, the transfer sheet size designation key 572, the number of copies setting key 573, the sheet processing setting key 574, document width sensor S _W, the document passes the sensor S _D, the transfer sheet Sensor _SP ,
The left member sensor S _H , the right member sensor S _M , the position sensor S _T, and the integrated height sensor S _S are connected and a predetermined signal is input thereto. Left member drive motor 361, right member drive motor 366, stapler drive motors 373, 374
The moving belt drive motor 386 is connected to the transport belt 346, the left width shifting member 353, the right width shifting member 355,
Each operation of the staplers 371 and 372 and the moving belt 385 is controlled.

The CPU 110 has a rewritable memory 114 for storing a document image and a passage time of the document based on the leading edge position signal and the trailing edge position signal of the document output from the document passage sensor _SD. Timer 1 to measure
15 is connected, the sheet processing determining means 116, the document number counting means 117, the copy number counting means 11
8, bundle number discriminating means 119, set number counting means 120,
Each unit includes a transfer paper size determining unit 121 and a bundle determining unit 122. The CPU 130 includes a sorting operation determining unit 134, a sorting direction determining unit 135, a width shifting member drive signal output unit 136, a transport belt drive signal output unit 137, a moving belt drive signal output unit 138,
And stapler drive signal output means 139.

The sorting operation discriminating means 134 includes a first
And the sorting direction determining means 135 includes a first direction determining means 143 and a second direction determining means 144.
In addition, the width shifting member drive signal output unit 136 includes the first drive signal output unit 145 and the second drive signal output unit 14.
6, the first drive signal output means 145 includes a first signal output means 147 and a second signal output means 148.
The second drive signal output unit 146 includes a third signal output unit 149 and a fourth signal output unit 150.

Here, the paper processing determination means 116 determines whether or not the stapling processing is set for the transfer paper bundle. The document number counting means 117 determines whether or not the original placed on the Counting the number of sheets,
The copy number counting means 118 continuously counts the number of copies made by the copying machine 1 from the first page to the last page for each set of transfer paper bundles.

The number-of-bundles discriminating means 119 determines whether or not the number of transfer papers discharged to the intermediate tray 341 has reached the number of sheets constituting a set of transfer paper bundles. A counter for counting the number of sets of transfer paper bundles discharged onto the intermediate tray 341;
Reference numeral 21 denotes whether the size of the transfer paper to which the document image is to be transferred is a first size (for example, B4 size) or a second size (for example, B5 size) smaller than the first size. The bundle determination unit 122 determines whether the transfer paper bundle discharged from the intermediate tray 341 is the last set of transfer paper bundles.

The sorting operation discriminating means 134 performs the first sorting operation (sorting operation on the first set of transfer paper bundles of a plurality of sets of transfer paper bundles) when the sorting means 343 sorts the transfer paper bundles. The first motion discriminating means 141 determines whether or not the transfer paper on which the document image is transferred by the transfer paper size discriminating means 121 is a second size (for example, B5 size). Is determined, it is determined whether or not this is the first sorting operation. The second operation determining unit 144 determines whether the transfer paper on which the original image is to be transferred by the transfer paper size determining unit 121 is the first.
(For example, B4 size), it is determined whether or not it is the first sorting operation.

The sorting direction determining means 135 determines whether the sorting direction of the previous transfer paper bundle by the sorting means 343 is one side (for example, the right side in FIG. 2) or the other side (for example, the left side in FIG. 2). The first direction discriminating means 14
Numeral 3 is for determining the sorting direction of the previous transfer paper bundle when the transfer paper is the second size, and the second direction determining means 144 is for determining the previous sorting direction when the transfer paper is the first size. The sorting direction of the transfer paper bundle is determined.

The width shifting member drive signal output means 136 outputs a drive signal for rotating the left member drive motor 361 and the right member drive motor 366 of the sorting means 343, and the first drive signal output means 145. Outputs a drive signal when the transfer paper is the second size. The second drive signal output unit 146 outputs
In this case, a drive signal is output in the case of the size.

That is, the first drive signal output means 145
The first signal output unit 147 of the first operation determination unit 141 determines that the first sorting operation is the first sorting operation, and the first signal output unit 147 is larger than the shift amount when the transfer paper is the first size. A drive signal for driving the left member drive motor 361 and the right member drive motor 366 to shift the transfer paper bundle to one side by the shift amount of 2 is output.
When the first direction discriminating unit 143 determines that the previous sorting direction is one side, the second signal output unit 148 is larger than the shift amount when the transfer paper is the first size. The left member drive motor 361 and the right member drive motor 3 shift the transfer paper bundle to the other side by the shift amount.
A drive signal for driving the drive 66 is output.

The third signal output means 149 constituting the second drive signal output means 146 outputs the transfer paper when the second operation determination means 142 determines that it is the first sorting operation. A drive signal for driving the left member drive motor 361 and the right member drive motor 366 so as to shift the transfer paper bundle to one side by a first shift amount smaller than the shift amount when the size is 2. The fourth signal output means 150 performs a shift when the transfer paper is of the second size when the second direction determination means 144 determines that the previous sorting direction of the transfer paper bundle is one side. A drive signal for driving the left member drive motor 361 and the right member drive motor 366 is output so as to shift the transfer paper bundle to the other side by a first shift amount smaller than the amount.

The conveyor belt drive signal output means 137 is provided with a conveyor belt drive motor 347 for driving the conveyor belt 346.
, A driving signal for rotating and driving the transfer belt bundle in a direction in which the transfer paper bundle is discharged.
Outputs a drive signal for rotating the moving belt driving motor 386 for driving the moving belt 385 in the direction in which the stack tray 381 is lowered. The stapler driving signal output unit 139 outputs the driving signal when the stapling process is set. When the number of transfer papers on the intermediate tray 341 reaches the number of transfer papers constituting the set of transfer papers, the stapler 3
A drive signal for rotating the drive motors 373 and 374 of 71 and 372 is output.

Next, an example of the overall operation of the image forming apparatus provided with the sheet post-processing device configured as described above will be schematically described. That is, in the copying machine 1, for example, a sort mode is selected by the mode selection key 572 of the operation panel 57, while a predetermined number of copies is set by the copy number setting key 573, and staple processing is set by the sheet processing setting key 574. For example, after the first document group including a predetermined number of documents of a small size (for example, B5 size), which is the second size, is placed on the document placing portion 91, the position of the transport guide member 96 is adjusted. The start button 571 is turned on.

As a result, the scanner 512 moves from the home position to the position of the second contact glass 72, while the original fed by the paper feed roller 93 is sequentially placed on the second contact glass 72 by the automatic original feeder 95. The document is conveyed, the document image is read by the scanner 512 and stored in the memory 114. The document for which the image reading has been completed is discharged to the document discharge unit 92. At this time, the size of the original placed on the original placing section 91 is automatically determined based on signals output from the original width sensor _SW and the original passage sensor _SD . The transfer paper size designation key 572
When the transfer paper size is set, the set size has priority over the automatically determined size.

The original image stored in the memory 114 is read out from the memory 114 at a predetermined timing to form a toner image on the photosensitive drum 53, and this toner image is supplied to the sheet feeding cassette 561 corresponding to the original size. Small size (for example, B5
(Size) transfer paper. The transfer paper on which the toner image has been transferred is fixed at the fixing unit 55, and is then discharged to the discharge port 5.
Then, the sheet is discharged to the sheet post-processing device 3 from the side 9.

In the sheet post-processing apparatus 3, the directional control valve 325 is initially switched to the position shown by the solid line, and the transfer sheet carried in from the carry-in port 31 is transferred to the main transport path 3
22. Therefore, the transfer paper discharged from the discharge port 59 of the copying machine 1 is transferred to the carry-in port 31.
From the main transport path 322
It is led to. In the main transport path 322, one of the direction switching valves 330 to 332 is switched to the position indicated by the solid line corresponding to the transfer paper size (the other direction switching valves are switched to the position indicated by the chain line). .), The transfer paper is discharged onto the intermediate tray 341 via the direction switching valve. During the operation of discharging the transfer paper onto the intermediate tray 341, the left and right width shifting members 353, 35 are arranged so that the transfer paper is discharged to the center in the width direction on the intermediate tray 341.
5 have been moved to respective predetermined positions near the center.

Then, when the number of transfer papers constituting the transfer paper bundle forming the set of the transfer papers discharged onto the intermediate tray 341 reaches the number of the transfer paper bundles, the stapler 371, 37 is attached to the transfer paper bundle.
The stapling process is performed by 2. Then, the transfer paper bundle is transferred to the intermediate tray 341 by the left and right width shifting members 353 and 355, and the size of the transfer paper constituting the transfer paper bundle is larger than the second size (for example, the first size).
(B4 size), is shifted by a second shift amount larger than the first shift amount, is sorted in the left-right direction, and is then conveyed upward by the conveyance belt 346 to the discharge path 4.
0 and the stack tray section 3 by the discharge roller pair 41
It is discharged to the 8 side. These left and right width shifting members 353,
The details of the sorting operation by the sorting means 343 provided with 355 will be described later.

During the discharging operation of the transfer paper bundle by the transfer belt 346, the direction switching valve 325 is switched to the position shown by the dashed line, and the transfer paper carried in from the carry-in port 31 is sent to the bypass conveyance path 323. The paper is temporarily stored in the bypass conveyance path 323. After the transport belt 346 returns to the home position, the transfer paper stocked in the bypass transport path 323 is transferred to the intermediate tray 3.
It is discharged on 41. For this reason, the copying operation in the copying machine 1 can be continued even during the discharging operation of the transfer sheet bundle by the transport belt 346.

A plurality of sets of transfer paper bundles sequentially discharged from the intermediate tray 341 are sequentially transferred onto the stack tray 381 and accumulated in a state where they are sorted in the left-right direction. Then, at the stage where a plurality of sets of transfer paper bundles corresponding to the number of copies are accumulated, the copying operation and the sorting operation of the first document group are completed. It should be noted that the stack tray 381 is
Each time the transfer paper bundle is discharged from above, the transfer paper bundle is lowered by a predetermined distance.

Subsequently, while the number of copies is reset by the copy number setting key 573 (when the number of copies is different from that of the first document group), the setting of the staple processing is canceled by the sheet processing setting key 574, and the large first number is set. Size (for example, B
After placing a second document group consisting of a predetermined number of documents (4 size) on the document placing portion 91, the start button 571 is turned on. As a result, the copying operation is started, and the transfer sheet bundle of the second document group in a state where the stapling process has not been performed is sequentially transferred onto the transfer sheet bundle of the first document group on the stack tray 381. The sheets are sorted in the left-right direction with the first shift amount smaller than the second shift amount.
Then, when a plurality of sets of transfer paper bundles corresponding to the number of copies are accumulated, the copying operation and the sorting operation of the second original group are completed.

The stapling process may be applied to the transfer sheet bundle of the second original group. When performing the stapling process on the transfer paper bundle of the second original group,
The sorting operation is not performed. That is,
In the present embodiment, when the transfer paper constituting the transfer paper bundle has the small second size, the transfer paper bundle is sorted regardless of the presence or absence of the stapling process. If the first size is large,
When the stapling process is not performed, sorting is performed on the transfer paper bundle, and when the stapling process is performed, the sorting is not performed. Further, the stack tray 381 is lowered by a predetermined distance each time the transfer paper bundle is discharged.

FIGS. 4 and 5 are flowcharts for explaining the sorting operation of the transfer sheet bundle by the sorting means 343. That is, when the start button 571 is turned on after the first original group is placed on the original placing section 91 and the above-mentioned predetermined copying conditions are set, copying is started, and the number of copies C Is counted (step S
1). This count, the transfer sheet is performed by the number of copies counting means 118 by receiving an output signal from the sensor S _P, from the first page of the transfer sheet constituting the transfer paper stack to be set to the last page each set It is counted continuously every time. This count value is updated and stored in the RAM 112 every time the copy number counting means 118 counts.

Next, the number-of-copies discriminating means 11 determines whether or not the number of copies C counted by the number-of-copies counting means 118 has reached the number of transfer papers constituting a set of transfer paper bundles.
9 (step S3). This determination is made by comparing the number of transfer papers constituting the set of transfer paper bundles. If the determination is negative, the process returns to step S1, and the subsequent operations are repeatedly executed.

As described above, the number of transfer sheets constituting a set of transfer sheet bundles is equal to the number of documents in the sort mode, and equal to the number of copies in the group mode. Further, the number of sets of transfer paper bundles is equal to the number of copies in the case of the sort mode, and is equal to the number of documents in the case of the group mode.
Therefore, in the case of the sort mode, the number of documents is counted by the document number counting means 117 by receiving a signal output from the document passage sensor _SD , and the count value is used as a transfer sheet forming a set of transfer paper bundles. When the number of copies is set by the copy number setting key 573, the set number is stored in the RAM 112 as the number of sets of transfer paper bundles.

In the group mode, when the number of copies is set by the number-of-copies setting key 573, the number of copies is stored in the RAM 112 as the number of transfer sheets constituting a set of transfer sheets. The number of documents is counted by document number counting means 117 by receiving a signal output from document passage sensor _SD , and this count value is stored in RAM 112 as the number of sets of transfer paper bundles.

When the determination in step S3 is affirmative (that is, when the number of copies C reaches the number of transfer papers constituting the set of transfer paper bundles), the number K of sets of transfer paper bundles is increased by the set number counting means. 120 (step S
5). This count value is updated and stored in the RAM 112. When the determination in step S3 is affirmative, it is determined that the staple processing is set by the paper processing determination unit 116 based on the signal from the paper processing setting key 574, and the stapling processing is performed on the intermediate paper tray 341. The stapling process is performed for the stapling process.

Next, the transfer paper size determining means 121 determines whether or not the size of the transfer paper on which the document image has been transferred is a second size smaller than the first size (step S7). The transfer paper size is determined by comparing the width dimension of the document and the length dimension in the transport direction with the transfer paper size stored in the ROM 111 in advance. The width dimension of the document is determined based on the signal output from the document width sensor S _W. The length of the original in the longitudinal direction is determined based on the leading end position signal and the trailing end position signal of the original outputted from the original passage sensor _SD, and the passage time of one original is measured by the timer 115. It is determined by the product of the passed transit time and the known document feed speed by the paper feed roller 93.

If the determination in step S7 is affirmative, the sorting operation to be performed by the sorting means 343 is the first sorting operation (sorting operation for the first set of transfer paper bundles of a plurality of transfer paper bundles). It is determined by the first operation determining unit 141 whether or not the operation is performed (step S9).
This determination is performed, for example, by determining whether or not the number of sets K of the transfer paper bundle counted in step S5 is one. That is, when the number of sets K is 1, it is determined that this is the first sorting operation.

If the determination is affirmative in step S9, the left and right width shifting members 353 and 353 of the intermediate tray 341 are set.
55 is the first size when the transfer paper size is the first size.
The drive signal for driving the left member drive motor 361 and the right member drive motor 366 to move to one side (for example, right side) with the second shift amount larger than the shift amount of It is output (step S11). Thereby, each member drive motor 361,3
The transfer paper bundle P discharged to the center on the intermediate tray 341 shown in FIG.
Due to 53 and 355, the sheet is shifted to one side shown in FIG. 6B by the second shift amount, and the transfer paper bundle P is sorted to one side.

Thereafter, a drive signal for driving the transport belt drive motor 347 to discharge the transfer paper bundle sorted to one side to the stack tray 381 is output by the transport belt drive signal output means 137 (step S1).
3). As a result, the transport belt 346 is driven to rotate, and the transfer paper bundle is transported upward, and is discharged to the stack tray 381 side. At this time, the discharge roller pair 40 is also driven to rotate in a direction to discharge the transfer paper bundle to the stack tray 381 side. When the discharge of the transfer paper bundle is completed, the transport belt drive motor 347 drives the transport belt 346 in the reverse direction to return to the home position. Also, left and right width shifting members 3
Reference numerals 53 and 355 also return to the original positions at which the transfer paper discharged from the copying machine 1 can be stored.

Next, the count of the number of copies C is cleared (step S15), and subsequently, it is determined by the bundle determining means 121 whether or not the last set of transfer paper bundles (step S1).
7). This determination is based on the counted number K of sets of transfer paper bundles.
And the number of sets of the first document group stored in advance (corresponding to the number of copies in the case of the sort mode). If the determination is negative, step S
Returning to step 1, the subsequent operations are repeatedly executed for the next set of transfer paper bundles.

If the determination in step S9 is negative (that is, in the case of the sorting operation for the second and subsequent sets of transfer papers in the first document group), it is determined whether the previous sorting direction is one side or not. It is determined by the first direction determining means 143 (step S19). If the determination is affirmative, the left shift member 353 and the right shift member 355 of the intermediate tray 341 are shifted to the second width larger than the first shift amount when the size of the transfer paper is the first size. A drive signal for driving the left member drive motor 361 and the right member drive motor 366 to move to the other side (for example, the left side) by the shift amount is output by the second signal output means 148 (step S21).

As a result, each member drive motor 361, 3
The transfer paper bundle P discharged to the center on the intermediate tray 341 shown in FIG.
Due to 53 and 355, the sheet is shifted to the other side shown in FIG. 6C by the second shift amount, and the transfer paper bundle P is sorted to the other side. Thereafter, the process proceeds to step S13, and the subsequent operations are repeatedly executed. When the transfer paper bundle is formed of the second transfer paper having a small size, the transfer paper bundle is sorted regardless of whether or not the stapling process is performed on the transfer paper bundle.

On the other hand, when the determination is negative in step S7 (that is, when the second original group is placed on the original placing section 91 and the size of the transfer paper is larger than the second size) Case), the second operation determining unit 142 determines whether or not the sorting operation to be performed by the sorting unit 343 is the first sorting operation (sorting operation for the first set of transfer paper bundles of the plurality of transfer paper bundles). It is determined (step S23). This determination is performed by determining whether or not the number of sets K of the transfer paper bundle counted in step S5 is 1 as described above.

If the determination is affirmative in step S23, the left shift member 353 and the right shift member 355 of the intermediate tray 341 are smaller than the second shift amount when the size of the transfer paper is the second size. Left member drive motor 361 to move to one side (for example, right side) by the first shift amount
Then, a drive signal for driving the right member drive motor 366 is output by the third signal output unit 149 (step S25). Thereby, each member drive motor 361,
The transfer paper bundle P discharged to the center on the intermediate tray 341 by driving the 366 is shifted to one side by the first shift amount by the left and right width shift members 353 and 355 (FIG. 6).
(A), (b)), the transfer paper bundle P is sorted to one side. Thereafter, the process proceeds to step S13, and the subsequent operations are repeatedly executed.

If the determination is negative in step S23 (ie, in the case of the sorting operation for the second and subsequent sets of transfer papers of the second original group), it is determined whether the previous sorting direction is one side or not. It is determined by the second direction determining means 144 (step S27). If this determination is affirmative, the left shift member 353 and the right shift member 355 of the intermediate tray 341 are shifted by the first shift smaller than the second shift amount when the transfer paper size is the second size. Left member drive motor 3 to move it to the other side (eg, left side)
A drive signal for driving the motor 61 and the right member drive motor 366 is output by the fourth signal output means 150 (step S29).

Thus, each member drive motor 361,3
The transfer paper bundle P discharged to the central portion on the intermediate tray 341 by driving the intermediate paper 341 is shifted to the other side by the first shift amount by the left and right width shift members 353 and 355 (FIG. 6A,
(C)), the transfer paper bundle P is sorted to the other side. Thereafter, the process proceeds to step S13, and the subsequent operations are repeatedly executed. If the determination is affirmative in step S17, the count of the number of sets K is cleared (step S31), and the copying operation and the sorting operation for the document group placed on the document placing section 91 are completed.

The present invention is constructed as in the above embodiment, so that even when a transfer paper bundle made up of large transfer papers is stacked on a transfer paper bundle made up of small transfer papers, the apparatus can be increased in size. It is possible to prevent the transfer paper bundle from slipping down, and to prevent the transfer paper bundle from slipping down without increasing the size of the apparatus even when a large number of transfer paper bundles composed of small stapled transfer papers are stacked. I can do it.

That is, in the sorting operation in the above embodiment, as shown in FIG.
Second size transfer paper stack P ₁ of the lower, which is integrated into previously on 1 small in size (e.g., B5-size size) if composed of transfer paper, often with a shift amount that the transfer paper stack P ₁ While being sorted by the second shift amount a, sorting is performed,
Big first size of the transfer paper stack P ₂ of the upper to be integrated on top thereof in size (e.g., B4 size paper size) if composed of transfer paper, shift the transfer paper stack P ₂ is the second Sorting is performed with a first shift amount b (b <a) smaller than the amount a. In the case in which the transfer paper stack P ₂ of the top as described above were subjected to the stapling process is not performed sorting the first shift amount b is set to zero.

As a result, in the lower transfer paper bundle P ₁ , even if stapling is performed, the staples S are located at positions separated from each other. sheet bundle P _2, the lower of the transfer sheet in a wide range of width R that is formed by the transfer paper stack in its lowermost and uppermost transfer paper stack of transfer paper stack P ₁ of the lower and the transfer paper stack thereunder to contact the bundle P _1, contact area is increased sliding of the upper part of the transfer paper stack P ₂ is prevented. As for the width R, an appropriate value is experimentally determined according to the paper quality and size of the transfer paper.

[0109] Also, because it is sorted by the transfer paper stack P ₂ is small shift of the upper, the transfer paper stack while also a stable be one transfer paper stack P ₁ of the lower consists transfer paper smaller It would be integrated on the P _1, also so that the slipping can be effectively prevented from this point. The shift amount of the transfer paper stack P ₂ consisting of the transfer paper of a large size,
For those less than the shift amount of the transfer paper stack P ₁ consisting of the transfer paper of a small size, it is not necessary to increase the intermediate tray 341 and the stack tray 381, device will not be large.

[0110] Further, since the sorting operation in the embodiment, as shown in FIG. 7 (b), the transfer paper stack P ₁ consisting of the transfer paper of a small size to be sorted by the second shift amount a, the stack tray even if only the transfer paper stack P ₁ is integrated onto the 381, now the transfer paper stack does not tilt since it exists at a position where the staple S has been separated from each other,
The transfer paper stack P ₁ is the transfer paper stack in the upper be many stages integrated is prevented from slipping.

Note that the present invention is not limited to the above-described embodiment, and various modifications as described below can be adopted.

(1) In the above embodiment, the sorting operation by the left and right width shifting members 353 and 355 is performed by moving the left and right width shifting members 353 and 355 to one side and the other side as shown in FIG. The transfer paper bundle accommodated in the central portion of the intermediate tray 341 is divided into one side position and the other side position separated from the center position, and the left and right width shifting members 353 and 355 are arranged. Can be moved only to one side or the other side to sort the central position, which is the storage position, and the position on one side or the other side.

That is, the transfer sheet bundle stored in the center position of the intermediate tray 341 is discharged onto the stack tray 381 as it is (that is, without shifting the transfer sheet bundle to one side or the other side), and the next. The transfer sheet bundle may be shifted to one side or the other side by the left and right width shifting members 353 and 355, and then discharged onto the stack tray 381. When the sorting direction of the transfer paper bundle is alternately reversed in such a method, the operation of the left and right width shifting members 353 and 355 can be shortened, and the sorting operation can be speeded up.

The state in which the transfer sheet bundle is not shifted to one side or the other side is a state in which no drive signal is output from any of the signal output means. The sorting means 343 by means 136 (first to fourth signal output means 147 to 150);
Of course is controlled.

(2) In the above embodiment, the sorting operation of the transfer paper bundle is performed by the sorting means 34 provided in the intermediate tray portion 34.
3, the sorting means can be provided on the stack tray section 38 side. For example, the entire stack tray section 38 is orthogonal to the discharge direction of the transfer paper bundle (the direction penetrating the paper surface in FIG. 1).
The slide mechanism is configured by a rack and a pinion or the like, and this slide mechanism is
1 can be realized by performing a sliding operation in the left and right direction in relation to the discharging operation of the transfer paper bundle from above. In this case, the CPU 130 or the like may be provided with a function realizing unit as a slide mechanism unit driving signal output unit instead of the width shifting member driving signal output unit 136.

(3) In the above embodiment, the case where the size of the transfer paper is two is described. However, the size of the transfer paper may be three or more. In this case, the shift amount may be changed for each size, or the shift amount may be changed for each group in a plurality of groups.

(4) In the above embodiment, the shift amount a of the transfer paper bundle made of the transfer paper of a small size is fixed regardless of the thickness of the transfer paper bundle. It is also possible to change it according to. That is, when the thickness of the transfer paper bundle is large, the shift amount a is reduced somewhat because the stiffness of the transfer paper bundle is increased and the force for supporting the transfer paper bundle formed of the large-sized transfer paper on the upper part is increased. Thus, the width R shown in FIG. 7A can be reduced.

(5) In the above embodiment, the function realizing means provided in the CPU for performing the sorting operation of the transfer paper bundle are the CPU 110 of the copying machine 1 and the CPU of the sheet post-processing device 3.
130, the CPU 110 of the copying machine 1 and the CPU 1 of the sheet post-processing device 3 are provided.
It is also possible to provide only one of them. Further, even when the CPU 110 of the copying machine 1 and the CPU 130 of the sheet post-processing apparatus 3 are respectively provided with the sharing, the sharing can be appropriately changed.

(6) In the above embodiment, the sorting operation is performed at the steps shown in the flowcharts of FIGS. 4 and 5, but the sorting operation is necessarily performed at the steps shown in the flowcharts of FIGS. No need. That is, as described above, in order to prevent the sorting in the case where the stapling process is performed on the transfer sheet bundle formed of the transfer sheet having the large first size, the stapling process is performed when the determination in step S7 is negative. Is set, and if it is determined that staple processing is not set, the steps after step S23 are executed, but it is determined that staple processing is set. Sometimes direct step S
13 may be performed.

(7) In the above embodiment, the center position in the sorting direction when the transfer paper bundle made of small transfer papers is sorted, and the center position in the sorting direction when the transfer paper bundle made of large transfer papers is sorted. However, if these two center positions are made to coincide with each other, a large transfer paper bundle composed of a large transfer paper is stacked on a transfer paper bundle composed of a small transfer paper. It is possible to more effectively prevent the transfer paper bundle made of from slipping off.

(8) In the above embodiment, a copying machine is used as an image forming unit for transferring an image to a transfer sheet. However, a printer is used as an image forming unit for transferring an image to a transfer sheet. It is also possible.

[0122]

As described above, according to the sheet post-processing apparatus of the first to fifth aspects, the shift amount increases when the size of the transfer paper is small, and decreases when the size of the transfer paper is large. Control means for controlling the sorting means so that the shift amount is changed according to the size of the transfer paper, so that a transfer paper bundle made of a large transfer paper is placed on a transfer paper bundle made of a small transfer paper. This makes it possible to prevent the transfer paper bundle from slipping down without increasing the size of the apparatus even when stacking paper, and to increase the size of the apparatus even when stacking only a large number of transfer paper bundles made of small transfer paper subjected to stapling. This makes it possible to prevent the transfer paper bundle from slipping off without any trouble.

According to the image forming apparatus of the present invention, when the size of the transfer paper is small, the shift amount is large, and when the size of the transfer paper is large, the shift amount is small. Control means for controlling the sorting means so that the shift amount is changed according to the shift amount, so that even when a transfer paper bundle made up of large transfer papers is stacked on a transfer paper bundle made up of small transfer papers, the apparatus can be used. Slipping of the transfer paper bundle can be prevented without increasing the size, and even when multiple transfer paper bundles consisting of small stapled transfer papers are stacked in multiple stages, the transfer paper bundle can slide down without increasing the size of the device. Can be prevented.

[Brief description of the drawings]

FIG. 1 is a side view schematically showing an internal configuration of an image forming apparatus provided with a sheet post-processing apparatus according to an embodiment of the present invention.

FIG. 2 is a plan view showing a configuration of an intermediate tray in the sheet post-processing device of the image forming apparatus shown in FIG.

FIG. 3 is a block diagram showing a control configuration centering on a sorting operation of a transfer paper bundle in the image forming apparatus shown in FIG. 1;

4 is a flowchart for explaining a sorting operation for a transfer sheet bundle in a sheet post-processing apparatus of the image forming apparatus shown in FIG. 1;

5 is a flowchart for explaining a sorting operation for a transfer sheet bundle in a sheet post-processing apparatus of the image forming apparatus shown in FIG. 1;

6A and 6B are diagrams for explaining a sorting operation for a transfer sheet bundle in the sheet post-processing device of the image forming apparatus shown in FIG. 1, wherein FIG. 6A illustrates a position of the transfer sheet bundle on an intermediate tray during storage; (B) is a diagram showing the position of the transfer paper bundle on the intermediate tray in a state of being sorted to one side, and (c) is a diagram showing the position of the transfer paper bundle on the intermediate tray in a state of being sorted to the other side.

7A and 7B are diagrams schematically illustrating a sorting state of a transfer sheet bundle on a stack tray that has been sorted by a sheet post-processing device of the image forming apparatus illustrated in FIG. 1; FIG. FIG. 7B is a diagram illustrating a case where transfer paper bundles made of large transfer papers are stacked and stacked on a bundle, and FIG. 8B is a diagram illustrating a case where only a transfer paper bundle made of small transfer papers and subjected to staple processing is stacked.

FIG. 8 is a diagram schematically illustrating a sorting state of a transfer sheet bundle on a stack tray that has been sorted by a conventional sheet post-processing apparatus, where (a) is a transfer sheet bundle of small transfer sheets that has been stapled; FIG. 7B is a diagram illustrating a case where transfer paper bundles made of large transfer papers are piled up and stacked on the top, and FIG. 7B is a diagram showing a case where only a transfer paper bundle made up of staple processing made up of small transfer papers is stacked.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Copier (image forming part) 3 Paper post-processing apparatus (paper post-processing part) 11, 13 Control part (control means) 121 Transfer paper size discriminating means (size discriminating means) 134 Sorting operation discriminating means 135 Sorting direction discriminating means 145 First drive signal output means (drive signal control means) 146 Second drive signal output means (drive signal control means) 341 Intermediate tray 343 Sorting means 381 Stack tray

Claims (10)

[Claims] A stack tray for stacking a plurality of transfer paper bundles formed from a plurality of transfer papers discharged from an image forming unit; and a transfer paper stack stacked on the stack tray, which is sorted by a predetermined shift amount and sorted. Sorting means for changing the shift amount according to the size of the transfer paper so that the shift amount increases when the size of the transfer paper is small, and decreases when the size of the transfer paper is large. And a control means for controlling the means. 2. The method according to claim 1, wherein the control unit is configured to transfer the transfer paper bundle to a predetermined first size when the size of the transfer paper is a predetermined first size.
When the size of the transfer paper is the second size smaller than the first size, the transfer paper bundle is sorted by the second shift amount larger than the first shift amount. 2. The sheet post-processing apparatus according to claim 1, wherein said sheet sorting device controls said sorting means. 3. The apparatus according to claim 2, wherein said control means includes a size discriminating means for discriminating a size of said transfer paper, and a drive signal control means for controlling driving of said sorting means in accordance with a discrimination result of said size discriminating means. The sheet post-processing device according to claim 1 or 2, wherein: 4. The first drive signal output means for driving the sorting means so as to have the first shift amount when the size of the transfer paper is the first size. And second drive signal output means for driving the sorting means so as to have the second shift amount when the size of the transfer paper is the second size. Item 6. A paper post-processing device according to Item 3. 5. A transfer paper bundle made of the second size transfer paper is stacked on a lower portion of the stack tray, and a transfer paper bundle made of the first size transfer paper is transferred to the second size transfer paper. 5. The sheet post-processing device according to claim 2, wherein the sheet post-processing device is stacked on a transfer paper bundle made of paper. 6. An image forming unit for transferring an image to transfer paper,
A stack tray for accumulating a transfer paper bundle composed of a plurality of transfer papers discharged from the image forming unit; a sorting unit for shifting and sorting the transfer paper bundle accumulated on the stack tray by a predetermined shift amount; When the size of the transfer paper is small, the shift amount is increased, and when the size of the transfer paper is large, the sorting unit is controlled such that the shift amount is changed according to the size of the transfer paper so that the shift amount is reduced. An image forming apparatus comprising a sheet post-processing device, comprising: a control unit. 7. The method according to claim 1, wherein the control unit is configured to transfer the transfer paper bundle to a predetermined first size when the size of the transfer paper is a predetermined first size.
When the size of the transfer paper is the second size smaller than the first size, the transfer paper bundle is sorted by the second shift amount larger than the first shift amount. 7. An image forming apparatus comprising a sheet post-processing apparatus according to claim 6, wherein said apparatus controls the sorting means. 8. The image processing apparatus according to claim 1, wherein the control unit includes a size determination unit configured to determine a size of the transfer sheet, and a drive signal control unit configured to control driving of the sorting unit according to a determination result of the size determination unit. An image forming apparatus comprising the sheet post-processing device according to claim 7. 9. The first drive signal output means for driving the sorting means so as to have the first shift amount when the size of the transfer paper is the first size. And a second drive signal output means for driving the sorting means so as to have the second shift amount when the size of the transfer paper is the second size. An image forming apparatus comprising the sheet post-processing device according to claim 8. 10. A transfer paper bundle made of the second size transfer paper is stacked on a lower portion of the stack tray, and a transfer paper bundle made of the first size transfer paper is transferred to the second size transfer paper. The image forming apparatus according to any one of claims 7 to 9, wherein the image forming apparatus is provided with a sheet post-processing apparatus.