JPH0996928A - Automatic both-side paper feeding device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an automatic both-side paper feeding device which prevents oblique feeding in the case of feeding a paper again. SOLUTION: A transfer paper 2 on an intermediate tray 5 is successively drawn by a drawing roller 9 and a feed roller 8 from the transfer paper on a lower part, and the drawn transfer paper 2 is carried by a carrying roller 11 for new image forming processing. In the case of the carriage, a pair of jogger fences 10 provided on the right and the left of the tray 5 can be opened and closed in a width direction with respect to the specified width of the paper 2, so that the position of the paper 2 is specified. The jogger fences 10 are closed before the specified time of the start of paper re-feeding and are opened after the specified time of the start of the paper re-feeding so that the paper 2 is aligned. Since the fences 10 are closed only during the paper re-feeding, such trouble as skew can be prevented in the case of the paper re-feeding, and carrying characteristic in the case the transfer paper enters the intermediate tray can be enhanced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic double-sided sheet feeding device such as a copying machine.

[0002]

2. Description of the Related Art Conventionally, an automatic double-sided sheet feeding device applied to an image forming apparatus such as a copying machine or a printer generally opens a jogger fence while transfer paper is being discharged onto an intermediate tray, and then opens the jogger fence after stacking. The method of closing and the method of always jogging at a fixed timing are taken.

[0003]

However, if the jogger fence is opened at the time of re-feeding, there is a tendency for skewing before reaching the grip roller, resulting in an oblique feed state. SUMMARY OF THE INVENTION It is an object of the present invention to provide an automatic double-sided sheet feeding device that prevents oblique feeding at the time of re-feeding.

[0004]

In order to achieve the above object, the automatic double-sided sheet feeding device of the present invention temporarily stacks the transfer paper having the image formed on one surface on the intermediate tray, and This is an automatic double-sided paper feeder that re-feeds one sheet at a time from the bottom of the transfer paper of the job and forms an image on the other surface of the transfer paper. A jogger fence for regulating the position of the transfer paper is provided, and the jogger fence is closed before the first predetermined time before the start of refeeding and the jogger fence is closed after the second predetermined time after the start of refeeding. It is characterized by opening.

After opening the jogger fence, it is preferable to close the jogger fence after a third predetermined time. Furthermore, the third predetermined time may be set according to the length of the transfer paper in the paper feed direction.

[0006]

Therefore, according to the automatic double-sided sheet feeding device of the present invention, the transfer sheets having the image formed on one side are temporarily stacked on the intermediate tray, and the lowermost sheet of the transfer sheets of one job is stacked. The sheets are sequentially re-fed one by one to form an image on the other surface of the transfer sheet. In this re-feeding, the jogger fence can be opened and closed in the width direction with respect to the specified width of the transfer sheet, and regulates the position of the transfer sheet. Position regulation is by closing the jogger fence a first predetermined time before the start of refeeding and opening the jogger fence after a second predetermined time after the start of refeeding.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of an automatic double-sided sheet feeding device according to the present invention will be described in detail with reference to the accompanying drawings. 1 to 6, there is shown an embodiment of the automatic double-sided sheet feeding device of the present invention. 1 to 4 show the operation procedure of the embodiment in a sectional view of an automatic double-sided sheet feeding device, and FIGS. 5 and 6 show an operation example of a jogger fence in a timing diagram.

The automatic double-sided sheet feeding device of this embodiment is provided with the transfer sheet 2
Discharge roller 1 for discharging the sheet onto the intermediate tray 5, the shifting roller 3, the pressure plate 4, the intermediate tray 5, the back fence 6, the separation belt 7, the feed roller 8, the calling roller 9, and the transfer paper 2.
It has a jogger fence 10 and a conveyance roller 11 that regulate the width direction of the.

The discharge roller 1 having the above structure is a rotary roller that discharges the transfer paper 2 on which the image forming process on one side is completed onto the intermediate tray 5. The approaching roller 3 has a rubber-made rotating roller provided at one end and a bearing at the other end, and the rotating roller moves up and down around the bearing. The rotating roller serves as a position regulating plate for the leading end portion of another transfer sheet that does not move the pressure plate 4 while pressing the transfer sheet discharged onto the intermediate tray from above and moving the transfer sheet with each rotation roller.

The pressure plate 4 is a plate for applying a predetermined pressing force to the transfer paper 2 on one side of which the image forming process on the intermediate tray 5 is completed. This pressing force is applied in order to transfer from the lower part of the plurality of transfer papers 2 one by one in order from the intermediate tray 5. Therefore, the intermediate tray 5 is configured to be movable up and down. The intermediate tray 5 is a tray for temporarily accommodating the transfer sheet 2 on which the image forming process on one side is completed.

The back fence 6 is a mechanism portion formed so as to be movable left and right in the intermediate tray 5. By this left-right movement, the transfer sheet 2 discharged onto the intermediate tray 5 is moved to the right in the figure for the next step. Separation belt 7
Is a belt for separating only the first transfer sheet 2 on the intermediate tray 5 from the second and subsequent sheets.

The feed roller 8 is a roller for feeding the transfer paper 2 on one side of which the image formation is completed on the intermediate tray 5 in a predetermined order to form an image on the other side. The calling roller 9 is a roller for pulling out the lowest transfer sheet 2 on the intermediate tray 5 and guiding it to the feed roller 8.

A pair of jogger fences 10a and 10b provided on the left and right of the intermediate tray 5 are a mechanism portion for regulating the width direction of the transfer paper 2. FIG. 4 shows a planar arrangement relationship and a conceptual operation direction of the jogger fences 10a and 10b, and a transfer motor (not shown) performs a jogging operation between a transfer paper width and a wider width.

The transport roller 11 is a roller that sequentially transports the transfer paper 2 for image formation. The transfer paper 2 on the intermediate tray 5 is sequentially drawn from the lower transfer paper by the calling roller 9 and the feed roller 8, and the drawn transfer paper is carried by the carrying roller 11 for a new image forming process.

An operation procedure example in the image forming apparatus of the present embodiment constituted by the above-mentioned respective parts will be described with reference to the drawings. In FIG. 1, the transfer sheet 2 which has been image-formed on one surface discharged from the discharge roller 1 is abutted against the pressure plate 4 which is descending by a shift roller 3 which rotates counterclockwise. Stacked on 5.

After the completion of one job, the pressure plate 4 is raised and the back fence 6 is moved to the right, whereby the stacked transfer papers 2 are transferred to the nip portion between the separation belt 7 and the feed roller 8 (FIG. 2). . Next, the pressing plate 4 is lowered to press and press the transfer paper 2, and the calling roller 9 is rotated clockwise.
The lowermost sheet of the stacked transfer sheets 2 is conveyed by the feed roller 8 which rotates in the clockwise direction similarly to the above. The second and subsequent sheets of transfer paper that move due to the frictional resistance that accompanies this conveyance are returned by the separation belt 7 that rotates clockwise.

At this time, the back fence 6 moves to the original position, and the transfer paper 2 for the next job is similarly stacked on the already stacked transfer paper 2 (FIG. 3).
The width direction of the transfer paper 2 is jogger fences 10a, 10b.
Are aligned by performing a jogging operation with a specified width of the transfer paper and a width wider than that (FIG. 4).

The timing of the above operation is shown in FIGS.
It will be described based on. The “refeed clutch” shown in FIGS. 5 and 6 is turned on when the transfer sheet 2 is pressed and pressed by the pressure plate 4.
This means the start of conveyance of the lowermost sheet of the transfer sheets 2 stacked by the calling roller 9 and the feed roller 8. Further, the opening and closing of the “jogger fence” indicates movement (open) in a direction wider than the specified width and movement (closed) in the specified width direction.

In the relationship of the above operation, FIG. 5 shows that the jogger fence is closed before the re-feeding for a fixed time A [ms].
The timing example of the operation of opening the jogger fence 10 after a fixed time B [ms] in which the re-fed transfer paper 2 is gripped by the transport roller 11 is shown.

The operation timing shown in FIG. 6 is the jogger fence 10 after a fixed time B [ms] in which the re-fed transfer paper 2 is gripped by the conveying roller 11, that is, after the transfer paper feed direction is determined. Is opened, and the jogger fence 10 is closed after a fixed time C [ms] of the re-feeding timing. C [m for a certain time to close this jogger fence 10
The time length of [s] is variable according to the paper length of the transfer paper.

In the above operation, the following effects are produced. (1) To close the jogger fence only during refeed,
It is possible to prevent problems such as skew during re-feeding, and it is possible to improve the transportability when the transfer sheet enters the intermediate tray. (2) Since the jogging operation is performed for a fixed time in accordance with the timing of re-feeding, it is possible to prevent problems such as skew during re-feeding with simple control. (3) Since the jogging operation is performed according to the refeed timing and the sheet length of the transfer sheet, it is possible to prevent problems such as skew during refeed with relatively simple control, and transfer to the intermediate tray. It is possible to improve the transportability when the paper enters.

The above embodiment is one example of the preferred embodiment of the present invention, but the present invention is not limited to this, and various modifications can be made without departing from the gist of the present invention.

[0023]

As is apparent from the above description, in the automatic double-sided sheet feeding device of the present invention, during refeeding, the jogger fence can be opened and closed in the width direction with respect to the specified width of the transfer sheet, and the refeeding is performed. The jogger fence is closed a first predetermined time before the start and the jogger fence is opened a second predetermined time after the start of refeeding. Therefore, by closing the jogger fence before starting re-feeding and opening it after starting re-feeding, it is possible to prevent the transfer paper from being positionally regulated and being re-feeded in the correct direction, and to prevent problems such as skew during re-feeding. it can.

[Brief description of drawings]

FIG. 1 is a sectional view of an automatic double-sided sheet feeding device showing an operation procedure example 1 of an embodiment of the automatic double-sided sheet feeding device of the present invention.

FIG. 2 is a sectional view of an automatic double-sided sheet feeding device showing an operation procedure example 2;

FIG. 3 is a sectional view of an automatic double-sided sheet feeding device showing an operation procedure example 3;

FIG. 4 is a plan view showing a configuration example of a jogger fence.

FIG. 5 is a timing diagram 1 showing an operation example of a jogger fence.

FIG. 6 is a timing diagram 2 showing an operation example of a jogger fence.

[Explanation of symbols]

 1 Ejection Roller 2 Transfer Paper 3 Crawler Roller 4 Pressure Plate 5 Intermediate Tray 6 Back Fence 7 Separation Belt 8 Feed Roller 9 Calling Roller 10 Jogger Fence 11 Conveyor Roller

Claims (3)

[Claims] 1. A transfer sheet having an image formed on one surface thereof is temporarily stacked on an intermediate tray, and the transfer sheets of the stacked one job are sequentially re-fed one by one from the bottom sheet, and the transfer is performed. In an automatic double-sided paper feeding device for forming an image on the other surface of a paper, the transfer paper has a jogger fence that can be opened and closed in a width direction with respect to a specified width, and regulates the position of the transfer paper. An automatic double-sided paper feeding device, characterized in that the jogger fence is closed a first predetermined time before the start of paper, and the jogger fence is opened after a second predetermined time after the start of refeeding. 2. The automatic double-sided sheet feeding apparatus according to claim 1, wherein after opening the jogger fence, the jogger fence is closed after a third predetermined time. 3. The automatic double-sided sheet feeding apparatus according to claim 3, wherein the third predetermined time is set according to the length of the transfer sheet in the sheet feeding direction.