JPH0592872A - Paper refeeding tray for image forming device - Google Patents

Abstract

PURPOSE:To facilitate storage to sheets to be stored in a paper refeeding tray and perform the regulation of both side ends to sheets to be refed by providing storage time regulating plates and refeeding time side regulating plates for correcting the direction and lateral position dislocation of the sheets. CONSTITUTION:A paper refeeding tray 6 is provided with storage time side regulating plates 10A and refeeding time side regulating plates 10B in order to correct the direction and lateral position dislocation of a sheet S. These storage time side regulating plates 10A and refeeding time side regulating plates 10B are alternately disposed on both lateral sides of the tray 6, and formed in such a way as to be movable in the direction orthogonal to the advance direction of the sheets S and to act independently. The sheet S is thereby corrected in its direction and lateral position dislocation while being stored in the refeeding tray 6.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a re-feeding tray provided in an image forming apparatus main body of an image forming apparatus such as a copying machine, a printer or a facsimile, which is capable of double-sided image formation and multiple image formation.

[0002]

2. Description of the Related Art In image forming apparatuses such as copiers, printers, and facsimiles, double-sided image formation is performed to form images on both sides of one sheet, or a plurality of images are formed on the same side of one sheet. Some of them enable multiple image formation.

FIG. 8 shows a conventional example of an image forming apparatus (copier) capable of such double-sided image formation and multiple image formation.

The image forming apparatus includes an image forming section 1 for forming an image on a sheet S, a sheet feeding section 2 for feeding the sheet S to the image forming section 1, and an image forming section 1.
The fixing unit 3 for fixing the image of the sheet S formed by
And a sheet discharge section 5 for discharging the sheet S for which image formation has been completed, and a re-feed tray for temporarily stacking and storing the sheets S that have been image-formed once and then fed to the image forming section 1 again. (Intermediate tray) 6 and re-feed sheet guide unit 7 for guiding the re-feed sheet S to the re-feed tray 6
Further, a sheet re-feeding unit 9 for re-feeding the sheets S stacked and stored in the re-feeding tray 6 to the image forming unit 1 is provided.

In this image forming apparatus, when the double-sided image forming mode or the multiple image forming mode is selected,
The sheet S once image-formed by the image forming unit 1 is not discharged to the sheet discharge unit 5 when the fixing process of the image is performed by the fixing unit 3, and the intermediate discharge unit 7A of the re-feed sheet guide unit 7 is discharged. It is stacked and stored on the re-feeding tray 6 via the sheet. When a predetermined number of sheets S are stacked and stored on the re-feeding tray 6, the sheet re-feeding unit 9 separates the sheets S one by one and re-feeds them to the image forming unit 1.

In this way, when the second image is formed on the sheet S, the image is fixed on the sheet S by the fixing unit 3 in the double-sided image forming mode or the double image forming mode. Then, the sheet is discharged to the sheet discharge unit 5.

By the way, when the double-sided image formation or the multiple image formation is performed as described above, from the time the sheet S is fed to the sheet feeding portion 2 to the time when it is stacked and stored on the re-feeding tray 6. The sheet S is often skewed because it has passed through a long conveyance path, and is skewed when it is stacked and stored on the re-feeding tray 6, so that the sheet is re-fed. The orientation of the sheet S on the paper tray 6,
Also, a shift occurs in the lateral position of the sheet S (the traveling direction of the sheet S is the vertical direction).

Therefore, the sheets S stacked and stored on the re-feeding tray 6 are in a state of being separately loaded, and if they are re-fed to the image forming section 1 as they are, skew, feeding failure, jam ( It may cause a paper jam). Further, in the multiple image forming mode, when the re-feeding sheet S has a positional deviation in the lateral direction, the superimposed images are misaligned (lateral misregistration), resulting in defective image formation.

For this reason, conventionally, the sheet re-feeding tray 6 has a sheet driven by a driving force of a motor or the like as sheet state correcting means for correcting the orientation of the sheet S and the positional deviation of the sheet S in the lateral direction. A side regulating side plate 10 that moves in a direction orthogonal to the traveling direction of S is provided.

The side regulating side plate 10 moves to a position corresponding to the sheet size that enters the refeed tray 6, and when the sheet S is stored, it waits at a position slightly wider than the sheet size and the sheet S is recharged. The jogging operation for facilitating storage in the paper tray 6 and moving from there to the sheet restriction position is repeated for each sheet, and the sheets S are stacked and stored on the re-feed tray 6, and both side edges of the sheets S are stored. It regulates and corrects the orientation of the sheet S and the positional deviation of the sheet S in the lateral direction.

Now, a method of feeding the sheets S stacked and stored on the re-feeding tray 6 will be described.

First, the sheets S stacked and stored on the re-feeding tray 6 are separated and fed one by one. For this, the tip of the sheet S is hooked by a claw portion and the elasticity of the sheet S causes The claw separation method for separating, the duplo method for separating the sheet S by the frictional force between the friction pad and the sheet S, and the feed roller 11 rotating in the sheet conveying direction as in the case of the sheet refeeding unit 9 of the present example. And a retard roller 12 which receives a rotational driving force through a torque limiter (not shown) and rotates in the sheet returning direction.
When the sheet is fed by the feeding roller 13, there is a retard separation system in which the sheet other than the topmost sheet is returned to separate the sheet.

The sheet S separated and fed by these separation methods is sent to the image forming section 1 by the pair of conveying rollers 15.

Then, as a method of sending out the sheets S stacked and stored on the re-feeding tray 6, the sheets S are sequentially transferred from the topmost sheet.
There are an upper separation system that separates and feeds the sheets one by one, and a lower separation system that separates and feeds the sheets one by one starting from the bottom sheet (in this example).

In the case of the upper separation method, since a predetermined number of sheets S on which the image has been formed for the first time are all stacked and stored on the re-feed tray 6, the sheets S are separated and fed, so that re-feeding is performed. The second image forming operation cannot be started until the last sheet S is stacked and stored on the tray 6. Therefore, it takes a long time until the sheet S is discharged out of the machine after the second image formation is completed, and particularly in a high-speed image forming apparatus, the production in the double-sided image forming mode and the multiple image forming mode is performed. Productivity is reduced.

On the other hand, in the case of the lower separation system, the sheets S stacked and stored on the re-feed tray 6 while sequentially stacking and storing the sheets S on which the first image is formed on the re-feed tray 6. Since it is possible to separately feed sheets, it is not necessary to start the second image forming operation after waiting for the last sheet S to be stacked and stored on the re-feeding tray 6 as in the upper separation method. ..

Therefore, in the case of the lower separation system, the first and second image forming operations can be continuously performed, and the productivity is not reduced in the double-sided image forming mode and the multiple image forming mode.

[0018]

[Problems to be Solved by the Invention] However, in this way,
In the case of the lower separation method with high productivity in the double-sided image forming mode and the multiple image forming mode, the sheet S is placed on the re-feeding tray 6.
Sheets stacked and stored, and the sheet S from the re-feed tray 6
When the re-feeding tray 6 having the conventional side regulating side plate 10 is used, the following problems occur.

That is, for example, the sheet S is the re-feed tray 6
If the operation of the side regulation side plate 10 is adjusted to the timing of being stored in the sheet S, the position for regulating the sheet S for re-feeding is displaced to the outside of the regular position, so that the sheet S
Of the sheet S and the lateral misalignment of the sheet S cannot be corrected, and the sheet S to be re-fed is skewed.

On the other hand, if the operation of the side regulating side plate 10 is adjusted to the re-feeding timing of the sheet S, the position of the side regulating side plate 10 when the sheet S is stored comes inside the normal position when the sheet S is stored. Therefore, the sheet S discharged from the intermediate discharge unit 7A of the re-feed sheet guide unit 7 may be skewed, and the sheet S may hit the side regulation side plate 10 on the re-feed tray 6 to cause a storage failure. It will cause you to come.

Such a problem can be solved by staggering the operation of the side regulating side plate 10 at the time of storing the sheet and the operation of the side regulating side plate 10 at the time of sheet re-feeding independently. However, in that case, the operation of storing one sheet S and then re-feeding one sheet S is not performed, and the operation of re-feeding the sheet S while storing the sheet S is not performed. Only that much time is required, and productivity is reduced.

Therefore, the present invention has been made in view of the above-mentioned circumstances, and it waits at a position where it is easy to store the sheets to be stored in the refeed tray, and the sheets are reloaded from the refeed tray. Provided is a sheet re-feed tray of an image forming apparatus, which is provided with a sheet state correction unit that regulates both side edges of a sheet to be fed and corrects the sheet orientation and the lateral position shift of the sheet. The purpose is to do.

[0023]

In order to achieve the above-mentioned object, the present invention has a side regulating side plate for storage for correcting the orientation of the seat (S) and the lateral displacement of the seat (S). (10A) and the side regulating side plate (10
B) and are included.

The side regulating side plate (10) for storing
A) and the side regulating side plate (10B) for re-feeding are characterized by operating independently of each other.

Furthermore, the side regulating side plate (1
The height of 0B) is the side regulation side plate (10) for storage.
It is characterized in that it is set lower than the height of A).

[0026]

According to the above structure, the sheet (S) stored in the refeed tray (6) and the sheet (S) refeed from the refeed tray (6) operate independently. Storing side regulating plate (10A) and refeeding side regulating plate (10A)
Individually regulated by B).

This makes it easy to store the sheets (S) stored in the refeed tray (6), and
For the sheet (S) re-fed from the re-feed tray (6), both side edges of the sheet can be regulated.

The reference numerals in parentheses are for reference to the drawings, and do not limit the configuration in any way.

[0029]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows an image forming apparatus (copier) provided with a re-feed tray according to the present invention, and FIGS. 2 to 4 show the re-feed tray.

In this image forming apparatus, the same members as those of the image forming apparatus of the above-mentioned conventional example are designated by the same reference numerals, and the description of those which are functionally and structurally the same will be omitted.

The image forming apparatus comprises an image forming apparatus main body 16
A document processing device 19 for feeding the documents set on the uppermost part of the document to the platen glass 17 one by one.

The refeed tray 6 has a sheet S orientation,
Also, a side regulation plate 10A for storage and a side regulation plate 1 for refeeding are provided for correcting the lateral misalignment of the sheet S.
0B is provided.

The storage side regulating plates 10A and the re-feeding side regulating plates 10B are alternately arranged on the left and right side portions of the tray 6, respectively. The storage side regulating plate 10A and the re-feeding side regulating plate 10B are movable in a direction orthogonal to the traveling direction of the sheet S and operate independently of each other. This operation is performed by the driving force of a motor or the like.

The height of the refeeding side regulating plate 10B is set lower than the height of the storing side regulating plate 10A. This is to prevent the sheets S stored in the re-feed tray 6 from being obstructed.

The re-feed tray 6 also has an intermediate discharge section 7
A sheet stopper 20 is provided for guiding the sheets S discharged from A onto the re-feeding tray 6 and stacking them. The sheet stopper 20 is rotatably attached about a support shaft 21, and is biased by a biasing spring 22 so that the leading end portion 20A contacts the upper surface of the tray 6.

The sheet stopper 20 is connected to the wire 23.
When the electromagnetic solenoid 25 is turned on, the electromagnetic solenoid 25 is turned upward around the support shaft 21 against the biasing spring 22 (see FIG. 4). At this time,
The front end portion 20A of the sheet stopper 20 is separated from the upper surface of the tray 6 by a distance t.

In FIGS. 1 to 4, reference numeral 26 is a sheet S.
Is a pair of paper discharge rollers provided in the intermediate discharge unit 7A for discharging.

Next, the operation of the image forming apparatus provided with the re-feeding tray 6 of the present invention will be described.

When the double-sided image forming mode or the multiple image forming mode is selected on the operation unit (not shown), the predetermined number of copies is set, and the copy start key is turned on,
The sheet S is fed from the sheet feeding unit 2. Then, after the image is formed on the sheet S by the image forming unit 1,
When the image fixing process is performed in the fixing unit 3, the sheet is not discharged to the sheet discharge unit 5 but is stacked and stored on the re-feed tray 6 from the intermediate discharge unit 7A through the re-feed sheet guide unit 7. ..
At this time, the electromagnetic solenoid 25 is off, and the sheet stopper 20 is in contact with the upper surface of the tray 6.

Sheet S discharged from the intermediate discharge section 7A
Is the re-feed tray 6 along the surface of the sheet stopper 20.
It hits the top and is loaded. At this time, the storage side regulation side plate 10A and the re-feeding side regulation side plate 10B are on standby at a position slightly outside the sheet size in a direction orthogonal to the traveling direction of the sheet S, and the sheet S is The sheet is easily guided to the sheet stopper 20 and the refeed tray 6.

When the sheet S is stored in the re-feed tray 6, the storage side regulating side plate 10A and the re-feeding side regulating side plate 10B with respect to the advancing direction of the sheet S by respective drive sources (not shown). As shown in FIG. 2, it moves a little in the orthogonal direction to the sheet size position, then returns to the original storage position and prepares for storage of the next sheet S. Then, the intermediate discharge part 7
The sheet S discharged from A is similarly fed to the sheet stopper 2
When the sheets are stacked on the front sheet S along the 0 plane, the storage side regulation side plate 10A and the re-feeding side regulation side plate 10B are also in a direction orthogonal to the traveling direction of the sheet S at this time as well. Further, the sheet S is on standby at a position slightly smaller than the sheet size, and the sheet S is easily guided to the sheet stopper 20 and the refeed tray 6.

As shown in FIG. 5, when the sheet S is stored in the re-feed tray 6, the storage side regulating side plate 10A and the re-feeding side regulating side plate 10B are driven by respective drive sources (not shown). A small amount of movement is made to a sheet size position in a direction orthogonal to the traveling direction of S, and then the original storage position is returned to prepare for storage of the next sheet S.

When the sheets are stored in the tray 6 for re-feeding, the side regulating side plate 10A for storing and the side regulating side plate 10B for re-feeding move as described above, and the sheet S is fed to the tray 6 for re-feeding.
The orientation of the sheet S and the positional deviation of the sheet S in the lateral direction are corrected while being stored on the upper side.

In this way, the sheets S on which the first image is formed are stacked and stored in the re-feed tray 6, and immediately before the first image formation is completed for the set number of sheets S, In the sheet refeed tray 6, preparation for sheet refeed is started, and the sheet refeed side regulation side plate 10B, which has been moving in the same manner as the sheet replenishment side regulation side plate 10A until now, is re-feed timing. The combined movement is performed independently of the storage side regulating side plate 10A.

At the same time that the second document is guided onto the platen glass 17 by the document processing device 19, the side-regulating side plate 10B for re-feeding moves a little outside from the side-regulating position corresponding to the size of the sheet S, If the jogging operation of returning to the position corresponding to the sheet size is repeated once or several times to completely correct the orientation of the sheet S and the lateral position shift (lateral registration) of the sheet S, the side for re-feeding The regulation side plate 10B stops at a side regulation position that matches the size of the sheet S, and regulates the lateral registration of the sheet S.
At this time, as shown in FIG. 6, the electromagnetic solenoid 25 is turned on, the sheet stopper 20 is released, and as described above,
The distance t from the upper surface of the tray 6 is resisted against the urging force of the urging spring 22.
However, the sheet S can be passed.

Then, the feeding roller 13 and the feed roller 11 rotate to convey the sheet S downstream, and the retard roller 12 rotates in the direction to return the sheet S via the torque limiter. As a result, the lowermost sheet of the sheets S stacked on the re-feed tray 6 is nipped by the nip portion A between the feed roller 11 and the retard roller 12 and tends to be conveyed downstream. At this time, the sheet S stacked on the lowermost paper is also conveyed along with the lowermost paper and is nipped by the nip portion A between the feed roller 11 and the retard roller 12. However, as shown in FIG. Pushed back to the upstream side,
As shown in FIG. 6, after all, only one sheet S is nipped and conveyed by the feed roller 11 and the retard roller 12,
It is sent to the pair of transport rollers 15.

By this operation, the sheets S stacked on the re-feeding tray 6 are separated one by one and sent to the image forming section 1 to be subjected to the second image formation, and the fixing section 3 forms the images on the sheets S. When it is fixed on the sheet, the sheet is discharged to the sheet discharging section 5.

At this time, the sheet S re-fed from the re-feeding tray 6 is conveyed to the image forming unit 1 at a timing immediately after the first image formation is completed, and the image forming unit 1 performs continuous operation in two steps. Since the second image formation is performed, productivity does not decrease in the double-sided image formation mode and the multiple image formation mode.

Even during the re-feeding operation, the storage side regulating side plate 10A performs the jogging operation independently of the movement of the re-feeding side regulating side plate 10B. For example, when the sheet re-feeding side regulation side plate 10B is at the sheet regulation position, the sheet S is guided to the sheet re-feeding tray 6 by the storage side regulation side plate 10A, and the sheet replenishment side regulation side plate 10A The lateral registration of the sheet S is corrected by the jogging operation. However, in some cases, the side regulation side plate 10B for re-feeding may hit, but the lateral registration is further corrected and stored during the jogging operation of the side regulation side plate 10B for re-feeding. Are stored in the re-feeding tray 6 while correcting the lateral registration, and the sheets S are sequentially transferred.
Will be loaded on top of.

[0051]

As described above, the re-feeding tray of the image forming apparatus of the present invention is provided with the side regulating side plate for storage for correcting the orientation of the sheet and the lateral misalignment of the sheet. Since the refeeding side regulation side plate is provided, the regulation of the sheets stored in the refeed tray and the regulation of the sheets refed from the refeed tray can be individually performed.

Therefore, it is easy to store the sheets stored in the re-feed tray, and it is possible to regulate both side edges of the sheets re-fed from the re-feed tray. Therefore, it is possible to support the lower separation method, which excels in productivity.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional side view of an image forming apparatus (copier) including a re-feeding tray according to the present invention.

FIG. 2 is a perspective view of a refeed tray according to the present invention.

FIG. 3 is a perspective view of a refeed tray according to the present invention.

FIG. 4 is a vertical cross-sectional side view of the refeed tray.

FIG. 5 is a schematic vertical cross-sectional side view for explaining an operation when a sheet is re-fed from the re-feed tray.

FIG. 6 is a schematic vertical sectional side view for explaining an operation when a sheet is re-fed from the re-feed tray.

FIG. 7 is a schematic vertical sectional side view for explaining an operation when a sheet is re-fed from the re-feed tray.

FIG. 8 is a vertical cross-sectional side view of an image forming apparatus (copying machine) of a conventional example.

[Explanation of symbols]

 10A Side regulating plate for storage 10B Side regulating side plate for refeeding S sheet

Claims (3)

[Claims] 1. An image forming apparatus comprising: a storage side regulating side plate for correcting a sheet orientation and a sheet lateral displacement, and a sheet re-feeding side regulating side plate. Refeed tray. 2. The re-feeding tray of the image forming apparatus according to claim 1, wherein the storage side regulating side plate and the re-feeding side regulating side plate operate independently of each other. 3. The image forming apparatus according to claim 1, wherein the height of the refeeding side regulating side plate is set lower than the height of the storing side regulating side plate. Refeed tray.