JPS60244737A - Paper feeder - Google Patents

Abstract

PURPOSE:To prevent paper dust from going out of a paper feeder, by bringing a paper dust remover into contact with a paper conveying roller. CONSTITUTION:The tip of a paper dust remover 9 is brought into contact with a paper conveying roller 8b which is one of two paper conveying rollers 8a, 8b which are provided in a pair and can be rotated. The remover 9 removes paper dust from the paper conveying roller 8b to prevent the paper dust from moving onto a photosensitive body. The inadequate cleaning of the photosensitive body, that of the roller of a fixation unit and the contamination of an image are thus prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a paper feeding device that can be used in electrophotographic copying machines, facsimile machines, light printing machines, and the like.

Conventional configuration and its problems In recent years, electrophotographic copying machines and facsimile machines have become rapidly popular.
At the same time, high quality images are also desired.

A conventional paper feeding device will be described below with reference to the drawings. FIG. 1 is a side sectional view of a conventional paper feeding device used in an electrophotographic copying machine, in which 1 is a paper feeding cassette, and 2 is paper stored in the paper feeding cassette 1. As shown in FIG. 3 is a paper push-up device, 4 is a paper feed cassette bottom plate, 6a and 5b are paper feed rollers, and 6 is a double feeding prevention member. 7a and 7b are paper feed guide plates, and 8a and ab are a pair of paper conveyance rollers.

The operation of the conventional paper feeding device configured as described above will be described below. A paper feed cassette 1 stores therein a large number of sheets of paper 2, which are stacked on a bottom plate 4 of the paper feed cassette. The paper push-up device 3 comes into contact with the paper feed cassette bottom plate 4 and plays the role of always bringing the topmost paper into contact with the paper feed opening roller 6a with stable pressure, regardless of the amount of paper. 5a,
5b is a paper feed roller made of a material with high frictional force such as rubber and has a one-sided clutch built into it; 5a and 5b
are connected by gears etc. The paper feed rollers 5a, sb
As the paper 2 rotates, the paper 2 is sent out from the paper feed cassette 1. The double feed prevention device 6 is made of a material with high friction such as rubber, and when multiple sheets of paper 2 are mistakenly fed from the paper feed cassette 1, the frictional force between the device 6 and the paper feed roller 5b causes the gap between the sheets to increase. Overcoming the frictional force, only the paper on the paper feed roller 5b side is fed into the paper feed guide Iiyama. Reference numerals 7a and 7b are paper feed guide plates, and the paper is fed between the two guide plates by a paper feed roller using a paper conveyance roller. The paper feed rollers 5a and 5b are such that the leading edge of the paper 2 is connected to the paper transport rollers 8a and sb.
When it reaches , it stops rotating.

The paper conveying rollers 8a, ab are a pair of rubber, metal, or a combination of rubber and metal, and correct the inclination of the leading edge of the paper being fed, and align it with the leading edge of the image on the photoreceptor (not shown). Rotation is started at the right timing so that the leading edge of the paper is aligned, and the paper is transported.

At this time, the paper feed rollers 5a and sb rotate together with the paper by the action of the one-sided clutch. A transfer unit (not shown) is attached to the paper sent to the photoconductor side by 8a and 8b.
The image on the photoreceptor is transferred.

However, in the above configuration, the paper powder held by the paper 2 (the cut surface of the paper or the paper feed rollers 5a, 6b)
, double feed prevention device 6, paper feed guide plates 7a, 73, paper transport rollers 8a, 8b, paper fibers generated by paper-to-paper contact and friction) are transferred onto the photoreceptor during transfer, causing damage to the photoreceptor. This method has problems such as poor cleaning, smearing of images, and poor IJ-coating of the rollers of the fixing device.

OBJECTS OF THE INVENTION It is an object of the present invention to provide a paper feeding device that effectively removes paper dust as described above.

Structure of the Invention The paper feeding device of the present invention is configured such that a paper dust removing member is brought into contact with at least one of a pair of rotatable paper transport rollers, thereby removing paper dust from the paper transport roller. , can prevent paper dust from transferring onto the photoreceptor.

DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 2 shows a side sectional view of a paper feeding device according to an embodiment of the present invention. In FIG. 2, 1 is a paper feed cassette, and 2 is paper stored in the paper feed cassette 1. 3 is a paper pushing device, and 4 is a bottom plate of a paper feeder. sa, 5
b is a paper feed roller, 6 is a double feeding prevention member, 7a and 7b are paper feed guide plates, and 8a and sb are a pair of paper conveyance rollers. The above is the same as the conventional example shown in FIG. Reference numeral 9 denotes a paper dust removing member which constitutes the main part of the present invention.

The operation of the paper feeding device of this embodiment configured as described above will be described below.

In this embodiment, the paper conveyance roller 8a is a rubber roller, and the roller 8b is a metal roller that rotates in the direction of the arrow at the same peripheral speed as that of a photoreceptor (not shown). In this embodiment as well, 8a and 8b are connected by gears, and pressure is applied between them to sandwich and rotate the paper and send it to the photoreceptor side. The role of these paper conveyance rollers 8a and ab is as follows.
This involves correcting the inclination of the leading edge of the paper and aligning the leading edge of the image on the photoreceptor with the leading edge of the paper. Therefore, rotation is started in response to an instruction from an image leading edge detecting means (not shown) on the photoreceptor, and is stopped after paper feeding is completed. At this time,
The paper feed rollers sa and sb are rotated according to the movement of the paper by a built-in one-sided clutch. Reference numeral 9 denotes a paper dust removing member that is in contact with the outer periphery of the paper conveying roller 8b, and has a diameter of 75 μm.
It is a polyethylene terephthalate film (trade name: Tetron, manufactured by Toshiku Co., Ltd.) with a thickness of . The distal end of the paper dust removal member 9 is brought into contact with the metal paper conveyance roller 8b to scoop up paper dust on the rotating paper conveyance roller.

Note that paper dust and the generation of paper dust have been explained in the conventional example, so the explanation here will be omitted. The generated paper dust is transferred to the paper conveyance roller 8a.

Although it has the property of adhering to the surface of 8b, it does not adhere to it because it is sold in a certain quantity. This is thought to be because, when the amount exceeds a certain level, the paper actually carries away paper dust. Therefore, as described in this embodiment above, by bringing the paper dust removal member into contact with the paper conveyance roller, paper dust on the paper conveyed from the paper feeding device can be removed. In the above embodiment, the paper dust removal member 9 was made of a polyethylene terephthalate film with a thickness of 76 μm, but it is not limited to this, and any material having appropriate elasticity and a function of scooping out paper dust may be used. Anything is fine. For example, various plastic films and metal plates can be used.

Next, other embodiments of the present invention will be described with reference to the drawings.

FIG. 3 shows a side sectional view of a paper feeding device according to another embodiment of the present invention. In this embodiment, the other paper conveying roller 8
A paper dust removing member 1o, which will be described later, is brought into contact with a. Paper powder is more likely to adhere to the rubber paper conveyance roller 8a than to the metal roller 8b due to the fine irregularities on its surface, the adhesiveness of rubber, and its charging properties. However, this does not stick beyond a certain point and is eventually taken out by the paper. Since a rubber roller has a high frictional force, it is difficult to use a film-like roller as a paper dust removing member as in the above-mentioned embodiment and to touch the tip of the film to remove paper dust. The paper dust removing member 1o in this embodiment has a diameter of 12
Each 100 μm stainless steel fibers are made into a bundle with 0.
They are arranged in rows at a density of 75 ML pitch. By bringing this into contact with the paper conveying roller 8a, paper dust is collected by the stainless steel fibers that are the paper dust removal member 10, and a paper dust removal effect is obtained. In the above embodiment, the paper dust removal member 1o is made of stainless steel fibers with a diameter of 12 μm, but the present invention is not limited to this, and any material can be used as long as it has the function of damming paper dust. good. For example, a flocked member, a plastic film, or a metal plate can be used in such a manner that the abdomen of the paper dust removing member is in contact with the paper conveying roller 8a.

Furthermore, another embodiment of the present invention will be described with reference to FIG. In this embodiment, a paper dust removing member 12 made of felt having a thickness of 3 mm is brought into pressure contact with a metal paper conveying roller 8b. Paper dust adhering to the metal paper conveyance roller 8b is collected by felt fibers, and a paper dust removal effect is obtained.

In the above embodiment, the paper dust removal member 12 is made of felt, but it is not limited to felt, and may be any material that has the function of wiping paper dust off the surface of the paper conveyance roller. Anything is fine.

For example, a nonwoven fabric or a sponge-like member can be used.

Effects of the Invention As is clear from the above description, the present invention is configured so that the paper dust removal member comes into contact with the paper conveyance roller of the paper feeder, so that it is possible to prevent paper dust from being taken out of the paper feeder. Therefore, poor cleaning of the photoreceptor, especially when applied to electrophotographic copiers.

Excellent effects can be obtained in that it is possible to prevent stains on images and poor cleaning of the rollers of the fixing device. Furthermore, since paper dust is removed from the paper conveyance roller, there is no slippage between the paper and the paper conveyance roller, and the position of the leading edge of the image on the photoreceptor and the leading edge of the paper is always stable.

Furthermore, the effect of the present invention is doubled by using a pair of paper transport rollers in combination with a paper dust removing member. For example, one of the paper conveyance rollers.

By using an elastic member having an edge and using a fibrous member for the other paper conveyance roller, the paper dust removal effect of the pair of paper conveyance rollers can be achieved at the same time.

[Brief explanation of the drawing]

FIG. 1 is a side sectional view of a conventional paper feeding device, and FIG. 2 is a side sectional view of a conventional paper feeding device. FIGS. 3 and 4 are side sectional views of paper feeding devices according to embodiments of the present invention, respectively. s a , s b - paper conveyance roller, 9, 10.12.
・-Paper dust removal member.

Claims (5)

[Claims] (1) A paper feeding device characterized in that a paper dust removing member is brought into contact with at least one of a pair of rotatable paper conveying rollers. (2) The paper feeding device according to claim (1), wherein the paper dust removing member is an elastic member having edges. (3) The paper feeding device according to claim (1), wherein the paper dust removing member is a fibrous member. (4) The paper feeding device according to claim (1), wherein the paper dust removing member is a felt-like member. (5) A paper feeding device according to claim (1), characterized in that an elastic member is brought into contact with one of the pair of paper conveyance rollers, and a fibrous member is brought into contact with the other.