JP2002002987A - Sheet feeding apparatus and image forming apparatus - Google Patents

Abstract

(57) [Problem] To stably feed a sheet P irrespective of the type and thickness of a sheet P to be used, while having a configuration having a feed tray in an upright state as a basic form of the apparatus. To do. SOLUTION: In a sheet feeding apparatus 3 having a storage means 30 for storing a sheet and a feeding means 100 for feeding a sheet from the storage means 30, the storage means 30 and the feeding means 100 are arranged in a device. Is rotatable between a substantially upright position and a substantially horizontal position, and can be fed in any of the postures.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet feeding apparatus for feeding sheets stored in storage means by feeding means, and a copying machine, a printer, a facsimile equipped with the sheet feeding apparatus, or any of these. The present invention relates to an image forming apparatus such as a multifunction peripheral having the functions of

[0002]

2. Description of the Related Art FIG. 5 shows a conventional image forming apparatus 400.
5 and 6, the image forming apparatus 400 is designed to reduce the occupied floor area. That is, the width of the image forming apparatus 400 does not depend on the length of the sheet P by setting the feeding tray 401 upright with respect to the apparatus, thereby saving space. As a result, there is no need to prepare an extra space in a narrow space such as an office.

[0003]

However, in the image forming apparatus 400 having the above structure, when the sheet is left for a long period of time in the standing state as shown in FIG. 5, the sheet P bends so as to undulate in the transport direction. There is a risk. Due to this phenomenon, the frictional force is locally reduced in a certain portion between the sheets P, causing double feeding at the time of feeding.

[0006] As shown in FIG.
When the sheet is fed, it is sharply bent, so that the sheet P is stressed, and in the case of a thin sheet, a curl occurs at the leading end, which is a distant factor that causes troubles and poor separation in the image forming transfer process. In addition, it was a distant cause of the jam due to the tip curl itself. Further, in the case of a thick sheet, the sheet is so stiff that it cannot cope with a sharp bend, and there is a possibility that a jam or breakage or damage of the sheet itself may occur. In this case, there are cases where restrictions such as removing a thick sheet are added to the specifications of a printable sheet.

Further, as shown in FIG. 6C, the leading end of the sheet P waiting on the feed tray 401 is bent by its own weight, which may cause a jam.

Accordingly, an object of the present invention is to stably feed a sheet P irrespective of the type and thickness of the sheet P to be used, while having a configuration in which the feeding tray 401 is in a standing state as a basic form of the apparatus. Is to be able to do.

[0007]

In order to achieve the above object, a typical configuration according to the present invention is a sheet having storage means for storing a sheet and feeding means for feeding the sheet from the storage means. In the feeding device, the storage unit and the feeding unit are rotatable between a substantially upright position and a substantially horizontal position with respect to the device, and can be fed in any of the postures. And

Further, the feeding means includes a rotating body for feeding the sheet, a supporting means for supporting a leading end of the stacked sheets so as to be able to freely contact and separate from the rotating body, and only a necessary sheet. And separating means for holding the remaining sheet by friction for feeding by the rotating body.

Further, in accordance with the rotation of the storage means and the feeding means, the support means changes the force of bringing the sheet into contact with the rotating body.

[0010] Further, as the storage means and the feeding means are moved from the substantially upright position to the substantially horizontal position with respect to the apparatus, the force of the support means for bringing the sheet into contact with the rotating body increases. .

[0011] The present invention is characterized in that the sheet storage capacity of the storage means changes in conjunction with the rotation of the storage means and the feeding means.

The sheet storage capacity of the storage means is increased as the storage means and the feeding means are moved from a substantially upright position to a substantially horizontal position with respect to the apparatus.

An image forming means for forming an image on a sheet; a feeding means for feeding the sheet to the image forming means;
In the image forming apparatus having:
A sheet feeding device according to any one of the above configurations is provided.

According to the above-described structure, while the device has a storage device in a standing position as a basic form of the device, the storage device and the feeding device are selected according to the type and thickness of the sheet to be used, the required output quality, and the quality. The posture is switched by rotating the means from a substantially upright position to a substantially horizontal position, and feeding can be performed in any of the postures.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of a sheet feeding apparatus to which the present invention is applied and an image forming apparatus having the same will be described in detail with reference to the drawings.

(First Embodiment) First, a first embodiment of the present invention will be described.

FIG. 1 is a schematic configuration diagram of an image forming apparatus provided with a sheet feeding device. FIG. 2 is a diagram in which the storage means 30 and the feeding means 100 of the sheet feeding apparatus of FIG. 1 are rotated.

In the image forming apparatus according to the present embodiment, a reader unit 1 for scanning a document and reading the information is arranged on the upper part of the main body. The reader unit 1 has a document table glass, a document illumination lamp, a mirror, an imaging lens, and a CCD. The document is placed on a platen glass and checked by a lamp. The reflected light is guided by an optical element such as a mirror, and the image reflected light is converted into an electric signal by a CCD through a lens.

A printer unit 2 for forming an image on a sheet is disposed below the leader unit 1, and a sheet feeding device 3 for feeding a sheet P for forming an image is attached. .

The printer unit 2 includes a process cartridge
The process cartridge 10 is rotatably supported, a photosensitive drum 11 rotatably supported, a primary charging unit 12 for uniformly charging the surface of the photosensitive drum 11,
Developing means 13 for developing the electrostatic latent image formed on the photosensitive drum 11 is integrally provided. Process cartridge
A laser scanner unit 20 is disposed above the light source 10. A light beam emitted and emitted from a semiconductor laser (not shown) scans and rotates a polygon mirror 21 and a folding mirror.
By 22, the photosensitive drum 11 is exposed and scanned. An electrostatic latent image is formed on the photosensitive drum 11 by exposure, and is made visible as a toner image by the developing unit 13. Then, the original image is reproduced on the sheet by transferring the toner image onto a sheet as a recording medium fed by the feeding roller 61 which is a rotating body. The sheet to which the toner image has been transferred reaches the fixing unit 70 through the conveyance path 62, where the toner image is fixed. As a result, all the steps of image formation are completed, and the sheet is discharged from the discharge unit 80 to the outside of the apparatus.

As described above, the sheet feeding device 3 attached to the printer unit 2 includes a storage unit 30 for storing sheets, and a feeding unit 10 for feeding sheets from the storage unit 30.
It is composed of 0. The feeding unit 100 includes a feeding roller 61 as a rotating body that feeds the sheet, a supporting unit 40 that supports the leading end of the stacked sheets so as to be able to freely contact and separate from the feeding roller 61, and In order to feed only the required sheet by the feed roller 61, the feeding roller 61 comprises a separation unit 50 that holds the remaining sheets by friction.

The storage means 30 includes a tray 32 capable of stacking and storing a plurality of sheets P, a side guide 31 for holding the sheets P without causing lateral displacement, and a housing.
Consists of 33. The support means 40 is provided with the side guide 31.
A medium plate 41 as a pickup guide is provided below the center plate, and the medium plate 41 is configured to be swingable about a shaft 42. Middle plate 41
Is urged by the middle plate pressure spring 43 so as to contact the feed roller 61. As a result, the sheet on the middle plate 41 comes into contact with the feed roller 61 and is fed out by the feed roller 61.

The separation means 50 includes a separation pad 51 and a pressure spring 52
Consists of The separation pad 51 as a separating friction member is pressed against a feed roller 61 as a rotating friction member. Further, the feed roller 61 and the separation pad 51 are made of rubber having a high friction surface such as silicon rubber or EPDM. In addition, it is not always necessary to make the whole the rubber material,
At least the surface should be made of rubber. Further, at least the feed roller 61 may be made of a rubber material.

The separation pad 51 is pressed against the feed roller 61 by a pressing spring 52 at a constant pressure. At the time of feeding, only the uppermost sheet of the sheet P is fed by the two functions of the feeding force of the feeding roller 61 for the uppermost sheet of the sheet P and the blocking force of the separation pad 51 for the sheet P. Each condition is set. Therefore, when there is an unseparated sheet among the sheets fed out by the feed roller 61 as described above, only the necessary sheet (in this embodiment, the highest sheet) is fed by the feed roller 61. Fed,
Other sheets are held by the separation pad 51.

The storage means 30 and the feeding means 100 configured as described above rotate around the same axis as the rotation axis of the feeding roller 61 between the substantially standing position shown in FIG. 1 and the substantially horizontal state shown in FIG. It is configured to be movable, and can be fed in any of its postures.

FIG. 2 shows an embodiment at a certain angle after the storage means 30 and the feeding means 100 are rotated. At the time of the rotation operation, the seat 43a of the intermediate plate pressing spring 43 slides on the guide portion 44a formed on the guide member 44 fixed to the bottom of the main body. The guide portion 44a has an arc shape having an imaginary center at the upper right portion of the feed roller 61 in FIG. Accordingly, the supporting means 40 is moved in synchronization with the rotation of the storage means 30 and the feeding means 100.
, The force of contact with the sheet changes. More specifically, as the storage means 30 and the feeding means 100 are moved from the substantially standing position to the substantially horizontal position with respect to the apparatus, the middle plate pressing spring 43
Is increased.

By setting the storage means 30 and the feeding means 100 in the posture shown in FIG. 2, the storage means 30 and the sheet conveying path downstream of the feeding roller have a linear relationship that is not substantially bent.
The configuration can cope with the feeding of a thick sheet without any problem.
Although a thick sheet or the like is a sheet having a low surface friction coefficient, in the configuration of the present invention, as described above, the storage means 30 and the feeding means 100 are moved from the substantially standing position to the substantially horizontal position with respect to the apparatus. As the pressing force of the middle plate pressing spring 43 urged by the feed roller 61 increases, the stable sheet feeding can be performed even for a sheet having a low surface friction coefficient such as a thick sheet. It is possible.

(Second Embodiment) Next, a second embodiment of the present invention will be described.

FIG. 3 is a schematic configuration diagram of an image forming apparatus provided with the sheet feeding device 3. FIG. 4 is a diagram in which the storage means 30 and the feeding means 100 of the sheet feeding apparatus 3 of FIG. 3 are rotated.

In this embodiment, members having the same functions and configurations as those of the first embodiment are denoted by the same reference numerals, and description thereof is omitted.

In this embodiment, in addition to the features of the first embodiment, the sheet storage capacity of the storage means 30 is changed in conjunction with the rotation of the storage means 30 and the feeding means 100. Specifically, the sheet storage capacity of the storage means 30 is configured to increase as the storage means 30 and the feeding means 100 are moved from a substantially upright position to a substantially horizontal position with respect to the apparatus.
The details will be described below.

In the present embodiment, the storage means 30 includes a side guide 31, a tray 32, a housing 33, and a rotating lever 34.
Having. The support means 40 includes a middle plate 41, a middle plate pressing spring.
43, and a middle plate pressure spring seat plate 47. Feeding means 10
Reference numeral 0 denotes a feed roller 61, the support means 40, and the separation means 50.

The separation pad 51 and the rotating lever 34 are fed rollers.
It is rotatable around the same axis as the 61 rotation axis. Further, the housing 33 is rotatable around a shaft 45 of the main body. The housing 33 has a shaft
An elongated hole 46a for guiding the shaft 46, a shaft 48 and a shaft 49 are formed, and a middle plate pressure spring seat plate 47 is arranged in a form supported by the shaft 46 and the shaft 48 at two points. The middle plate 41 is supported by a shaft 49,
Further, the sheet is pressed by the middle plate pressing spring 43 to come into contact with the feed roller 61. The separation pad 51 and the pressure spring 52 are provided for the rotating lever 34.

When the rotating means 34 rotates the storage means 30 and the feeding means 100 with the rotating lever 34, the separating pad 51 and the pressing spring 52 provided on the rotating lever 34 cause the feeding roller 61 to rotate. It rotates around the same axis as the rotation axis. Also a rotating lever
A shaft 46 provided on 34, a shaft 48 and a shaft 49 formed in the housing also rotate about the same axis as the rotation axis of the feed roller 61. The housing 33 rotates about the shaft 45 in conjunction with the movement of the shaft 46. In addition, the middle plate pressure spring seat plate 47 supported at two points by the shafts 46 and 48 also interlocks to change the posture with respect to the device from substantially upright to substantially horizontal. Further, the position of the middle plate 41 supported by the shaft 49 is changed similarly to the above-described middle plate pressing spring seat plate 47.

FIG. 4 shows an embodiment at a certain angle after the storage means 30 and the feeding means 100 are rotated. The middle plate 41 and the middle plate pressing spring seat plate 47 are in a positional relationship in which the pressing force of the middle plate pressing spring 43 increases. Also, in conjunction with the aforementioned rotation, the middle plate
The interval between the feed roller 41 and the tray 32 and the feed roller 61 is increased.
Therefore, by rotating the storage means 30 and the feeding means 100 to the posture shown in FIG. 4, the storage means 30 and the sheet conveyance path downstream of the feeding roller have a linear relationship that is not substantially bent,
The height at which the sheets can be stacked and stored in the storage means 30 changes greatly. For this reason, in the present embodiment, the storage means 30 and the feeding means
The closer the 100 is to the device from a substantially upright position to a nearly horizontal position,
The sheet feeding capacity is improved, and the sheet storage capacity can be increased.

(Other Embodiments) In the above embodiment,
Although the sheet feeding apparatus for feeding the sheet to be recorded has been illustrated, the present invention is not limited to this. For example,
The same effect can be expected by applying the present invention to another sheet feeding device such as a sheet feeding device for feeding a sheet such as a document to be read.

Also, in the above-described embodiment, the sheet feeding device integrally provided in the image forming apparatus has been exemplified.
The present invention is not limited to this, and similar effects can be expected even if the present invention is applied to a sheet feeding device detachable from the image forming apparatus. .

[0038]

As described above, according to the present invention,
The storage means and the feeding means are rotatable with respect to the apparatus from a substantially upright position to a substantially horizontal position, and can be fed in any of the postures. Despite the configuration having the means, the storage means and the feeding means are rotated from substantially upright to substantially horizontal according to the type and thickness of the sheet to be used and the required quality and quality of output, and the posture is switched. , Can be fed in any of these postures. This makes it possible to cope with the feeding of a thick sheet without any problem.

Further, by changing the contact force of the supporting means with the rotating body in conjunction with the rotation of the storage means and the feeding means, the reliability of the overall sheet feeding is further improved.

Further, by changing the sheet storage capacity of the storage means in conjunction with the rotation of the storage means and the feeding means, the sheet storage capacity can be increased as compared with the standing state.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of an image forming apparatus including a sheet feeding device (first embodiment).

FIG. 2 is a diagram in which a storage unit and a feeding unit of the sheet feeding device are rotated.

FIG. 3 is a schematic configuration diagram of an image forming apparatus including a sheet feeding device (second embodiment).

FIG. 4 is a diagram in which a storage unit and a feeding unit of the sheet feeding device are rotated.

FIG. 5 is a diagram of a conventional image forming apparatus.

FIG. 6 is a cross-sectional view of a conventional image forming apparatus and an enlarged view thereof.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Leader part 2 ... Printer part 3 ... Sheet feeding apparatus 10 ... Process cartridge 11 ... Photoconductor drum 12 ... Primary charging means 13 ... Developing means 20 ... Laser scanner unit 21 ... Polygon mirror 22 ... Folding mirror 30 ... Storage means 31 … Side guide 32… Tray 33… Housing 34… Rotating lever 40… Support means 41… Medium plate 42… Shaft 43… Medium plate pressing spring 43a… Seat 44… Guide member 44a… Guide 45… Shaft 46… Shaft 46a … Long hole 47… Medium plate pressure spring seat plate 48… Axis 49… Axis 50… Separation means 51… Separation pad 52… Pressure spring 61… Feed roller 62… Conveyance path 70… Fixing means 80… Ejection means 100… Feeding means 400: image forming apparatus 401: feeding tray

Continuing on the front page (72) Inventor Masakazu Mori 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Hideki Mori 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. F-term (reference) 3F343 FA02 FB02 FC01 GA03 GB01 GC01 GD01 HD09 HD18 JA01 JD08 JD33

Claims (7)

[Claims] 1. A sheet feeding apparatus comprising a storage unit for storing sheets and a feeding unit for feeding sheets from the storage unit, wherein the storage unit and the feeding unit are substantially upright with respect to the device. A sheet feeding device that is rotatable between a horizontal position and a substantially horizontal position, and is capable of feeding in any posture. 2. The sheet feeding device according to claim 1, wherein the sheet feeding unit includes a rotating unit configured to feed the sheet, a supporting unit configured to support a leading end of the stacked sheets so as to be able to freely contact with and separate from the rotating unit, And separating means for frictionally holding the remaining sheet for feeding by the rotating body.
The sheet feeding device as described in the above. 3. The sheet feeding device according to claim 2, wherein the support unit changes a force of bringing the sheet into contact with a rotating body in conjunction with the rotation of the storage unit and the feeding unit. Feeder. 4. The force with which the supporting means contacts the rotating body with the sheet increases as the storage means and the feeding means are moved from a substantially upright position to a substantially horizontal position with respect to the apparatus. The sheet feeding device according to claim 3. 5. The sheet feeding device according to claim 2, wherein a sheet storage capacity of the storage unit changes in conjunction with rotation of the storage unit and the feeding unit. 6. The sheet storage capacity of the storage unit increases as the storage unit and the feeding unit are moved from a substantially upright position to a substantially horizontal position with respect to the apparatus.
The sheet feeding device as described in the above. 7. An image forming apparatus comprising: an image forming unit that forms an image on a sheet; and a feeding unit that feeds the sheet to the image forming unit, wherein the feeding unit is used as the feeding unit. An image forming apparatus comprising the sheet feeding device according to any one of the preceding claims.