JPH05278878A - Paper sheet feeding device of image forming device - Google Patents

Abstract

PURPOSE:To eliminate generation of excessive wears or the like of a roller by providing a mechanism to release the action of an external paper sheet feeding device for small-sized paper sheets when two kinds of paper sheet feeding roller devices are arranged in order to cope with handling of smaller- and larger-sized paper sheets in a paper sheet feeding device to be provided in a paper sheet feeding tray of the like. CONSTITUTION:A paper sheet feeding device to be arranged in a paper sheet feeding part from a paper sheet feeding tray or the like consists of an inner side paper sheet feeding device 10 and an outer side paper sheet feeding device 20, and the respective devices are provided with a mechanism to be used also as a paper sheet separating mechanism. In the outer side paper sheet feeding device 20, a mechanism to separate a retard roller 23 from a driving roller 21 by means of a solenoid 26 by the information to feed the smaller sized paper sheets is arranged, enabling paper-feeding only by means of the inner side paper sheet feeding device 10.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet feeding device arranged in a sheet feeding portion of an electrophotographic copying machine, and more particularly to a sheet feeding tray such as a universal tray capable of feeding various sizes of sheets. In a paper feeding device provided with two types of paper feeding roller devices, it is possible to cancel the paper feeding action of the outer paper feeding device for small-sized paper and prevent wear of the roller member. Related to the device.

[0002]

2. Description of the Related Art In an image forming apparatus using an electrophotographic system such as an electrophotographic copying machine or a laser printer, a toner image formed on an image bearing member such as a photosensitive drum is transferred to a sheet and the toner image is transferred. A means for fixing a sheet to be carried by a fixing device to make a copy is used. As the paper feeding means used in the image forming apparatus, a paper feeding tray, a paper feeding cassette or the like for accommodating fixed-size paper is used, but in addition, a universal tray or the like capable of accommodating paper of any size is also used. Be done. In a paper feeding device provided for a paper feeding tray or the like that accommodates only the standard size paper, the paper feeding roller is arranged at a position corresponding to the paper size, and the paper feeding action can be performed in a good state. I am trying.

In addition to the paper feed tray that stores the standard size sheets, the universal tray is configured to accommodate a plurality of types of sheets, from small size sheets to large size sheets. Therefore, it is proposed to use a wide roller, as shown in Japanese Utility Model Laid-Open No. 61-191335, in order to send out a sheet of any size from the tray in a state in which skew feeding does not occur. Has been done. In the sheet feeding device of the conventional example, a wide sheet feeding roller is provided at a position such that the sheet of the smallest size used in the image forming apparatus extends over the side opposite to the reference line for conveying the sheet. It is said that the sheet feeding roller can exert the sheet feeding action in a good state even for a large size sheet.

[0004]

However, as shown in the above-mentioned conventional example, when a wide paper feed roller is used and a small size paper is fed, one side of the paper feed roller becomes the paper. A state occurs in which they are engaged and the other side slides on the retard roller or the friction pad. And
At the portion not in contact with the paper, the roller is abraded by the retard roller or the like, which causes a problem such as excessive wear of the roller. Further, since a part of the sheet feeding roller slides on the friction pad or the like, it is necessary to increase the driving force for the sheet feeding roller, which causes a problem that the driving mechanism for the sheet feeding device becomes large. Further, when a state where only a part of the paper feed roller is excessively worn occurs, the paper fed by the paper feed roller may be obliquely fed or the like. Then, it is difficult to correct the sheet fed in the oblique state to a normal state in the middle of the sheet conveyance path, which leads to a problem that a defective copy is easily formed.

Therefore, in order to solve the above-mentioned problems, it has been proposed to provide two sheet feeding roller devices in the sheet feeding device as shown in FIG. In the example shown in FIG. 7, the paper feeding device arranged on the paper feeding side of the paper feeding tray 1 corresponds to the inner paper feeding device 5 arranged at a position corresponding to the small-sized paper P1 and the large-sized paper. The outer sheet feeding device 6 is disposed, and a mechanism for driving the two sheet feeding roller devices 5 and 6 by using one drive shaft 7 is configured. As for the papers sent out from the paper feed tray 1 by the paper feed device, small size papers are fed only by the inner paper feed device 5, and large size papers are fed by the two paper feed roller devices 5 and 6. Therefore, the sheet sent out toward the sheet conveying path 2 is not fed obliquely in the state where it is supplied to the conveying roller device 8 and the subsequent conveying operation is normally performed.

However, as shown in FIG.
When one paper feed roller device is arranged, since two paper feed rollers feed paper for a large size paper, the paper can be delivered well, but for small size paper. Is in a state in which the roller member of the outer paper feeding device 6 on the outer side idles. That is, when feeding a small size sheet, a state occurs in which the drive roller of the outer sheet feeding device 6 rotates only while being strongly rubbed by the retard roller and the like. Then, the drive roller is strongly rubbed against the retard roller supported at the fixed position, so that the wear of these rollers becomes large, and in addition, the driving force for the drive shaft is wasted. Occur.

In addition to the above-mentioned problems, as shown in FIG. 8, in the electrophotographic copying machine 50 and the like, a manual feed tray is provided on the side of the apparatus main body 51, separately from the paper feed mechanism from the paper feed tray. 52 is arranged, and O is inserted from the manual feed tray.
A mechanism for feeding HP sheets and the like is provided. The manual feed tray 52 is provided on the side of the main body of the apparatus so as to be openable and closable, and is provided with a mechanism that can be fixedly held while leaning against the side of the main body 51 when not in use.

However, as shown in FIG. 8, when the manual feed tray is arranged, it is greatly protruded to both sides of the apparatus main body together with the discharge tray for storing the copy, so that the installation area of the electrophotographic copying machine is large. There is a drawback that Further, although the manual feed tray is leaned against the side of the main body in a folded state when not in use, the holding action of the paper in the tray is inaccurate, and if some impact is applied. There is also a problem that the tray swings easily. Further, even when a sheet feeding device having a mechanism as shown in FIG. 7 is arranged on the manual feed tray, excessive abrasion of rollers occurs when feeding small-sized sheets, There is a problem that it is necessary to set a large driving force.

[0009]

SUMMARY OF THE INVENTION The present invention solves the above-described problems of the conventional sheet feeding device, and when two sheet feeding roller devices are arranged, when feeding a small size sheet, An object of the present invention is to provide a device that releases the nip of the outer sheet feeding device and prevents an unnecessary driving action on the outer sheet feeding device.

[0010]

According to the present invention, there is provided a paper feed tray for accommodating a large number of paper sheets, and a friction rotating member arranged at a paper feeding portion of the paper feed tray. The present invention relates to a sheet feeding device configured to feed one side of a sheet to be stored along a sheet feeding reference guide. In the paper feed roller device of the present invention, the rotary friction member is composed of an inner paper feed device adapted to the smallest size paper and an outer paper feed device adapted to the largest size. A mechanism for arranging a mechanism for canceling the feeding action with respect to the outer sheet feeding device, and a mechanism for canceling the sheet feeding action for the outer sheet feeding device when a sheet of a size not corresponding to the outer sheet feeding device is fed. Is provided. Further, in the present invention, the outer paper feeding device adapted to the maximum size sheet is provided with a retard roller swingably, and when feeding a small size sheet, the pressing of the retard roller against the drive roller is released. A mechanism can be provided.

As described above, since the sheet feeding device is configured by providing the two types of sheet feeding roller devices, in the present invention, the large sheet size is stabilized by the two sheet feeding rollers. Since the paper feeding operation can be performed, the paper is not obliquely fed, and a stable paper feeding operation can be performed. Further, when feeding a small size sheet, the feeding action in the outer side feeding device is canceled, so that the retard roller is not pressed against the driven roller. It is possible to prevent excessive wear and the like of the member. Therefore, in the paper feed roller device of the present invention, since the roller member that is not in contact with the paper is not excessively driven, it is possible to directly rub the drive roller and the retard roller or the retard pad in the paper feed roller device. Therefore, the driving force for the roller member can be reduced.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A sheet feeding device of an image forming apparatus of the present invention will be described with reference to the illustrated example. The example shown in FIG. 1 is similar to the case of the conventional example shown in FIG.
1 illustrates a configuration of a portion that feeds a sheet from the sheet feeding path to the sheet feeding path 2. The sheet feeding device provided in the sheet feeding portion of the sheet feeding tray 1 includes an inner sheet feeding device 5 and an outer sheet feeding device 6. Composed of. The inner sheet feeding device 5 and the outer sheet feeding device 6 are arranged such that a driving roller and a retard roller face each other, and constitute a sheet feeding mechanism and a sheet separating mechanism. In the paper separating mechanism of the present invention, a retard roller or a retard pad can be arranged so as to oppose the paper feeding roller as in the case of the conventional paper feeding device. An example in which a retard roller is combined with a drive roller as a paper roller has been described.

In the paper feed mechanism of the present invention, one side of the paper feed tray 1 and the paper transport path 2 is set as the paper feed reference guide 3, and one side surface of the paper is used as the reference guide 3. The image is conveyed along with, and the operation such as image transfer is performed. Further, in the paper feeding device of the present invention, the inner paper feeding device 5 is arranged at a position inside the side line distant from the reference guide 3 so as to correspond to the smallest size paper P1, and to accommodate small size paper. Make it compatible with paper feeding. Further, an outer sheet feeding device 6 is arranged outside the center line 4 of the sheet conveying path so that it can be adapted to feed a large size sheet. Therefore, when feeding a large-sized sheet, the two sheet feeding roller devices 5 and 6 are capable of simultaneously exerting the action of feeding and separating the sheets, thereby preventing double feeding of the sheets and The action of sending out toward the transport path is performed.

The sheet feeding device arranged in the sheet feeding section from the sheet feeding tray 1 can be constructed as shown in FIG. 2. In the example shown in FIG. 2, for convenience of explanation. Unlike the case of FIG. 1, the inner sheet feeding device is shown by reference numeral 10,
The outside paper feeder is shown at 20. In the example shown in FIG. 2, the drive rollers 11 and 21 are attached to the drive shaft 1 with respect to the two paper feed roller devices 10 and 20 that form the paper feed device.
2 and the retard roller 1 with respect to the drive roller
3 shows a mechanism for pressing the sheets 3 and 23 to configure the sheet separating mechanism.

In the inner sheet feeding device 10, the drive shaft 1
A retard roller 13 is provided so as to face the drive roller 11 provided on the second roller 2. The retard roller 13 is supported by a support shaft 16 provided on a support bracket. Also,
A spring 17 is arranged with respect to the support bracket 14, and is oscillated by the spring via a shaft 15 to press the retard roller 13 toward the drive roller 11, thereby providing a predetermined nip pressure between the rollers. Is set. The retard roller 13 is
As in the case of the retard roller provided in the conventional paper separating mechanism, the roller member is non-rotatably provided, or
Any supporting mechanism such as providing via a reversing mechanism can be applied.

Apart from the inner sheet feeding device 10, the outer sheet feeding device 20 is arranged outside the central portion of the sheet conveying path.
Is a combination of a drive roller 21 provided on the drive shaft 12 and a retard roller 23, and constitutes a mechanism for carrying a sheet and performing a separating action. As shown in FIG.
The retard roller 23 is provided on the support bracket 24 via a support shaft 25, is swingably supported on the shaft 15 supporting the bracket, and the spring 27 presses the retard roller 23 against the drive roller 21. It constitutes the mechanism to do. Further, a drive mechanism by a solenoid 26 is arranged on the bracket of the retard roller shown in FIG. The solenoid 26 has a shaft 2
9 is connected to a substantially L-shaped link 28, an end portion of the link 28 engages with the bracket 24, and the retard roller 23 supported by the bracket is connected to the drive roller 21.
Try to get close to and away from.

As shown in FIG. 2, the outer paper feeder 20 of the present invention is provided with a sensor S for detecting the paper size at a predetermined position of the paper feed tray. When the paper set in the paper feed tray 1 is of a small size that cannot be detected by the sensor S, the solenoid is energized by a paper out signal from the sensor S. Then, via the link 28, the support bracket 24
Is swung in the clockwise direction via the support shaft 15 to separate the retard roller 23 from the drive roller 21.
When the paper is sent out by 0, the outer paper feeding device 20 is prevented from exerting the function of conveying the paper. When the solenoid is de-energized, the retard roller 23 is pressed against the drive roller 21 by the force of the spring, and the paper separating action can be exerted.

In the example shown in FIGS. 2 and 3, when feeding a large size sheet, the sensor S outputs a signal indicating that the sheet has been detected, so that the outer sheet feeder 20 is shown. The two roller members 2
1, 23 are brought into contact with each other so as to separate the sheets and carry them. In the example shown in FIG. 2, there is a case where a mechanism for detecting the paper size is provided for the paper feed tray and the nip of the paper in the outer paper feeder is released by a signal from the detection mechanism. Although shown, it is also possible to use a means by which the operator inputs information on the size of the paper stored in the paper feed tray by using the keys of the control panel or the like.

In the sheet feeding device of the present invention, the retard roller of the outer sheet feeding device is moved by moving the side guides as shown in FIG. 4 in order to release the nip of the roller device in the outer sheet feeding device. It is possible to configure a mechanism for swinging. In the example shown in FIG. 4, the guide member 3 on the reference line side and the regulating member by the side guide 30 are arranged for the paper stored in the paper feed tray, and the side guide 30 allows the side portion of the paper to move. It is possible to use means for performing the operation of releasing the nip of the outer sheet feeding device by the side guide when the regulation is performed.

The side guide 30 has an operating member 31.
And the bracket 2 of the outer paper feeding device.
The actuated member 32 corresponding to No. 4 has a pressing surface 3 on its side.
3 is formed. The actuating member 31 slides on the pressing surface 33 to move the actuated member 32 to the shaft 34.
Is swung counterclockwise about the shaft, and the bracket supporting the retard roller is swung about the shaft 15.
Release the pressure contact state of the two rollers. In the example shown in FIG. 4, as the mechanism for releasing the pressing of the retard roller by the side guide, any cam-shaped member or the like can be used in addition to the illustrated mechanism.

In the outside paper feeding device of the present invention, the retard roller is oscillated as described above to form the gap between the two roller members, and as shown in FIG. It is also possible to provide a mechanism for allowing the fixing and free rotation. In the example of the outer paper feeder 20 shown in FIG. 5, a mechanism for holding the retard roller 40 in a fixed position is provided in the state where the paper is separated, and therefore, the shaft 41 of the roller 40 is cammed with respect to the cam. Member 4
2 is provided. A link 45 driven by a solenoid 46 is provided on the cam surface 43 of the cam member 42, and when the link is in contact with the cam surface 43, the retard roller 40 is held at a fixed position.

In the outside paper feeder 20 shown in FIG. 5, a solenoid 46 is arranged to drive the link, and when the solenoid is energized to move the plunger 47 to the right side of the drawing, the link is supported. Is released,
The cam member 42 is swung to the position indicated by the phantom line, and the engagement with the cam member 42 is released. And the retard roller 4
In the state where the lock of the link to 0 is released, the retard roller 40 rotates in accordance with the drive roller even if the drive roller 21 is driven. Therefore, the retard roller idles in the state where no paper is inserted. Therefore, if the outer paper feeding device shown in FIG. 5 is applied to the outer paper feeding device shown in FIG. 2, the retard roller will idle for small-sized paper. The roller member of the paper device is not worn unnecessarily, and no extra driving force is required.

The sheet feeding device of the present invention configured as described above can be used not only as a sheet feeding means from a general sheet feeding tray but also as a sheet feeding means from a manual feeding tray. Further, as shown in FIG. 6, the paper feeding device of the present invention can be applied to a case where the manual feed tray is arranged on the side surface of the copying machine body as a vertical type. In the example shown in FIG. 6, in order to accommodate a plurality of sheets in a standing state, a vertical manual feed tray 55 is arranged, and a paper feeding device 56 is provided below the manual feed tray 55.

The paper feeding device 56 is, for example, as shown in FIG. 2, the inside paper feeding device 10 for small size paper.
Can be configured by combining the mechanism corresponding to the outer sheet feeding device 20 with respect to a large-sized sheet. For the outer sheet feeding device, a mechanism for swinging the retard roller can be provided. Can be placed. Then, as described above, when setting a large-sized paper on the vertical manual feed tray, one side surface of the large-sized paper can be positioned with respect to the side guide in the fixed position. To do. In addition, by arranging two types of paper feed members in the width direction of the paper with respect to the vertical manual feed tray,
It is possible to hold and position the sheet in the tray and to feed the sheet from the tray in a good state.

Further, in the present invention, as shown in FIG. 6, when the vertical type manual feed tray is arranged on the side of the copying machine body, the manual feed tray can be provided at a fixed position. Therefore, unlike the conventional device shown in FIG. 8, it is not necessary to open and close the manual feed tray. Therefore, even when the manual feed tray is used, the manual feed tray 55 does not largely project to the side of the main body of the copying machine, and the floor area occupied by the electronic copying machine can be reduced. In addition, as described above, the paper feeding device provided on the manual feed tray is
By arranging one paper feed roller device and configuring the nip releasing means in the one paper feed roller device, the paper separating action and the paper feeding action can be satisfactorily exhibited.

[0026]

As described above, the sheet feeding device of the image forming apparatus of the present invention is provided with the two types of sheet feeding roller devices to constitute the sheet feeding device. It is possible to perform a stable paper feeding operation with respect to the above paper by the two paper feeding rollers. Then, the sheet is not obliquely fed, and a stable feeding operation can be performed. Further, when feeding a small size sheet, the feeding action in the outer side feeding device is canceled, so that the retard roller is not pressed against the driven roller. It is possible to prevent excessive wear and the like of the member. Therefore, in the paper feed roller device of the present invention, since the roller member that is not in contact with the paper is not excessively driven, it is possible to directly rub the drive roller and the retard roller or the retard pad in the paper feed roller device. Therefore, the driving force for the roller member can be reduced.

[Brief description of drawings]

FIG. 1 is a plan view showing a configuration of a sheet feeding device according to the present invention.

FIG. 2 is a perspective view showing a configuration of a paper feeding device of the present invention.

FIG. 3 is a side view showing a configuration of a drive mechanism for the outer side sheet feeding device.

FIG. 4 is a perspective view showing the configuration of another embodiment of the paper feeding device of the present invention.

FIG. 5 is a side view of another example of the locking mechanism of the retard roller with respect to the outside paper feeding device.

FIG. 6 is a side view showing the configuration of a vertical manual feed tray.

FIG. 7 is a plan view showing a configuration of a conventional paper feeding device.

FIG. 8 is a side view of a conventional copying machine.

[Explanation of symbols]

1 paper feed tray, 2 paper feed path, 3 paper feed reference guide, 10 inner paper feed device, 11 drive roller, 13 retard roller, 14 support bracket, 20 outer paper feed device, 21 drive roller,
23 retard roller, 24 support bracket,
26 Solenoid, 30 Side Guide, 31
Operating member, 32 operated member, 33 pressing surface, 40 retard roller, 42 cam member,
45 link, 46 solenoid, 50 electronic copying machine, 55 vertical manual feed tray, 56 paper feeder.

Claims (2)

[Claims] 1. A paper feed tray for storing a large number of paper sheets,
A paper feeding device including a friction rotating member arranged at a paper feeding portion of the paper feeding tray, and configured to feed one side of the paper stored in the paper feeding tray along a paper feeding reference guide. In the mechanism described above, the rotating friction member includes an inner sheet feeding device that accommodates the smallest size sheet and an outer sheet feeding device that accommodates the largest size, and a mechanism for canceling the feeding action to the outer sheet feeding device. A sheet feeding device for an image forming apparatus, wherein when feeding a sheet of a size that does not correspond to the outer sheet feeding device, the sheet feeding action on the outer sheet feeding device is released. 2. The outer sheet feeding device adapted to the large size sheet is provided with a retard roller swingably, and releases the pressing force of the retard roller against the driving roller when feeding the small size sheet. The sheet feeding device of the image forming apparatus according to claim 1, further comprising a mechanism.