JPH0575650B2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention has a paper cassette receiving member removably built into the main body, and each roller is pivotally supported from the paper cassette in the installed state. The present invention relates to an image forming apparatus that transports paper via a pair of downstream feeding rollers, and particularly relates to a release mechanism for a pair of feeding rollers that is linked to the loading/unloading operation of a paper cassette receiving member.

(Prior Art) Conventionally, in a copying machine that has a copy paper cassette receiving member removably built into the copying machine main body,
When a paper jam occurs, the jam removal process is often performed by removing the copy paper cassette receiving member and removing the jammed copy paper. If resist pressure is applied to the pair of rollers, or if the roller pair is pinched, the copy paper may be torn off, which not only makes the jam removal operation difficult, but also wastes the copy paper.

In particular, it has a structure in which a copy paper cassette is built into the main body and a separate cassette is attached to the side of the main body. Paper is fed from the former cassette in a so-called boomerang style, and from the latter cassette. In the so-called straight type copying machine, it is difficult to install an openable/closeable lid for jam removal on the side plate of the main body due to the space constraints of the configuration.
The cassette built into the main body must be removed from the main body. However, if one end of the copy paper remains pinched by the registration roller,
Even if the cassette is removed, it is difficult to remove the copy paper. Furthermore, in the boomerang type paper feeding configuration, since the copy paper is curved (turned) in a U-shape, it is not easy to remove the copy paper unless the registration pressure is released. Furthermore, if the copy paper cassette is of a type in which the ejecting direction is perpendicular to the copy paper feeding direction, it is extremely difficult to remove jams without tearing the jammed copy paper unless the resist pressure is released. be.

(Object of the Invention) The present invention solves the above-mentioned problems, and includes applying a pressure contact force to a pair of feeding rollers in conjunction with the installation and removal operations of a paper cassette receiving member that is removably built into the main body. It is an object of the present invention to provide a mechanism for releasing a pair of feeding rollers, which has a simple structure and can facilitate jam removal work by enabling release.

(Structure of the Invention) The present invention has a paper cassette receiving member removably built into the main body, and in the attached state, the paper cassette is moved from the paper cassette through a pair of downstream feeding rollers, each of which is pivotally supported. In an image forming apparatus in which paper is conveyed by using a paper cassette receiving member, the bottom surface of the paper cassette receiving member and the supporting portion of the main body base on which the paper cassette receiving member is removably placed, in the loading/unloading direction of the paper cassette receiving member. A height giving structure is provided so that the paper cassette receiving member is displaced in height in the vertical direction when the paper cassette receiving member is attached or removed, and the paper cassette receiving member When the paper cassette receiving member is mounted on the main body, the pair of feeding rollers act in a direction that generates pressure contact with each other in accordance with the upward height displacement of the paper cassette receiving member, and when the paper cassette receiving member is removed from the main body. In the release mechanism for the pair of feeding rollers, the pressure contact force is applied in a direction to release the paper cassette receiving member depending on the height displacement of the paper cassette receiving member in the lower direction.

With this configuration, the pressing force between the pair of feeding rollers can be released simply by removing the paper cassette receiving member from the main body.

(Example) An example of the present invention will be described with reference to FIGS. 1 and 2.

A copy paper cassette 2 is placed on the main body base 1 of the copy machine.
A built-in base 3 is used as a support section on which a built-in copy paper cassette receiving member (hereinafter referred to as built-in base) 3 is placed, in which a
Guide rollers 4 and 5 having a height difference are provided at a predetermined interval in the loading/unloading direction (in this embodiment, the front-back direction). These guide rollers 4 and 5 are provided in pairs at predetermined intervals according to the width dimension of the built-in base 3 in a direction perpendicular to the loading/unloading direction, and the guide roller 5 on the back side in the loading/unloading direction is closer to the front. It is set higher than the guide rollers 4 on the side.

Further, the bottom surface of the built-in base 3 that comes into contact with the support formed by the guide rollers 4 and 5 is also formed into steps 3a, 3b, and 3c so as to give height differences in the loading/unloading direction, with the back side being higher than the front side. It's getting expensive.
By moving the built-in base 3 in the removal direction from the attached state to the main body as shown by arrow A in FIG. 2, the built-in base 3 is lowered while maintaining its entire horizontal state. Additionally, at the upper front end of the built-in base 3, there is a pair of push-up rollers 5 that push up a registration roller mounting plate 9, which will be described later.
is supported by the shaft 5a.

Furthermore, between the front side plate 6 and the rear side plate 7 of the main body, one of the registration roller pairs, an upper registration roller 8a, is rotatably supported, and one end of the registration roller mounting plate 9, which supports the registration lower roller 8b, is rotatably supported. It is rotatably supported on a shaft 9a. This registration roller mounting plate 9 is attached to the registration lower roller 8b.
It has an arm portion 9b that supports the resist roller mounting plate 9, and a protrusion portion 9c that extends downward at approximately the midpoint between the shaft support portion of the registration roller mounting plate 9 and the shaft support portion of the registration lower roller 8b. When the lower surface of this protruding portion 9c comes into contact with the push-up roller 5 and the built-in base 3 is installed in a predetermined position on the main body, the push-up roller 5 rotates the registration roller mounting plate 9 with the shaft 9a being a fulcrum. The arm portion 9b is pushed up, and the lower registration roller 8b is brought into pressure contact with the upper registration roller 8a, so that a predetermined registration pressure is obtained.

On the other hand, when the built-in base 3 is moved toward the front side of the main body (in the direction of arrow A in FIG. Because the built-in base 3 moves downward due to the difference, the push-up roller 5
1, and the registration roller mounting plate 9 rotates about the shaft 9a as a fulcrum in the direction of arrow B in FIG.
The state shown by the two-dot chain line in FIGS. 1 and 2 is reached, and the resist pressure is released. In order to restrict the rotation range of the registration roller mounting plate 9, a stopper 10 is provided on the front side plate 6 and the rear side plate 7, with which the arm portion 9b of the registration roller mounting plate 9 comes into contact.

Although the detailed structure is not shown in the drawings, the copy paper 1 stored in the copy paper cassette 2 is provided on the main body side.
The paper feed roller 12 for feeding the copy paper 11 in the copy paper cassette 2 moves from the state indicated by the two-dot chain line to the state indicated by the solid line in conjunction with the installation of the built-in base 3, and the paper feed roller 12 for feeding the copy paper 11 in the copy paper cassette 2
It is configured to be able to feed paper. In addition, the first
In the figure, an arrow C indicated by a chain double-dashed line indicates a boomerang-type feeding path for copy paper.

In this embodiment, the mounting/removal direction of the built-in base 3 (front and back)
Since the configuration is such that the and paper feeding direction are perpendicular to each other, when removing the built-in base 3 during jam processing, if the resist pressure is released by slightly moving the built-in base 3, this resist This prevents the jammed copy paper from tearing when the operator inserts his/her hand into the main body and takes out the jammed copy while the pressure is released.

In this embodiment, the mounting/removal direction of the built-in base 3 is the left-right direction of the main body, and is the same direction as the copy paper feeding direction. A guide roller 4 as a support portion on which the built-in base 3 on the main body base 1 is placed;
A pair of guide rollers 5 are provided at predetermined intervals in the insertion/removal direction with a height difference, and the guide rollers 5 on the mounting side (right side in this embodiment) are better than the guide rollers 5 on the extraction side (left side in this embodiment). It is set higher than 4. The other configurations are the same as those of the previous embodiment.

In this embodiment as well, the resist pressure is released by pulling out the built-in base 3, and since the loading/unloading direction of the built-in base is the same as the paper feeding direction,
Jammed copy paper can be removed very easily.

It should be noted that the present invention is equally applicable to an automatic duplex stock cassette instead of the copying machine cassette 2 described above.

(Effects of the Invention) As described above, according to the present invention, a height difference structure is provided that displaces the paper cassette receiving member in the height direction in accordance with the loading/unloading operation, and one roller of the pair of feeding rollers is pivotally supported. When the paper cassette receiving member is attached to the main body, the pair of feeding rollers acts on the paper in a direction that generates a pressing force against each other in accordance with the height displacement of the paper cassette receiving member in a higher direction;
When the paper cassette receiving member is removed from the main body, the pressing force is applied in a direction that releases the paper cassette receiving member in accordance with the height of the paper cassette receiving member in the lower direction. By taking out the jammed paper, the jammed paper can be removed without tearing, and the jamming process becomes easier.

[Brief explanation of the drawing]

FIG. 1 is a front view of a registration roller release mechanism according to an embodiment of the present invention, FIG. 2 is a right side view of the same, and FIG.
The figure is a front view of another embodiment, and FIG. 4 is a right side view of the same. 1... Body base, 2... Copy paper cassette, 3
... Copy paper cassette receiving member, 4, 5 ... Guide roller (support part), 8a ... Registration upper roller, 8
b...Registration lower roller, 9...Registration roller mounting plate.

Claims (1)

[Claims] 1. An image forming apparatus that has a paper cassette receiving member removably built into the main body, and that transports paper from the paper cassette through a pair of downstream feeding rollers each of which is pivotally supported when the paper cassette is attached. , in the loading/unloading direction of the paper cassette receiving member,
The bottom surface of the paper cassette receiving member and the supporting portion of the main body base on which the paper cassette receiving member is removably placed are provided with a support member so that the paper cassette receiving member is displaced in height in the vertical direction when the paper cassette receiving member is installed or removed. is provided with a height difference imparting structure, and when the paper cassette receiving member is attached to the main body with respect to the loin pivot member of one of the pair of feeding rollers, the height difference is provided in response to the height displacement of the paper cassette receiving member in the higher direction. When the paper cassette receiving member is removed from the main body by causing the pair of feeding rollers to act in a direction that generates pressure contact with each other, in the middle of the process, the above-mentioned pressure is applied in accordance with the downward height displacement of the paper cassette receiving member. A release mechanism for a pair of feeding rollers, characterized in that the pressure contact force is applied in a direction to release the pressure contact force.