JP2002362772A - Image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image forming device provided with a paper powder eliminating means capable of continuously keeping the eliminating effect for paper powder attached to a paper feed roller, applicable to the paper feed roller made of an elastic materials such as rubber. SOLUTION: A driving roller 4a is provided with a first paper powder eliminating member 10 and a second paper powder eliminating member 11 in the circumferential direction. The paper powder eliminating member is composed of a foamed body 11b, and an elastic body 11a for pressing the foamed body 11b to the driving roller 4a, and mounted on a part of a main frame 7 (in a case of the second paper powder eliminating member). The paper powder attached to a surface of the driving roller 4a is blocked by the first paper powder eliminating member 10, and subsequently the paper powder remaining on the surface of the driving roller 4a not eliminated is blocked by the second paper powder eliminating member 11.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus including a copying machine, a printer, a facsimile, and a multifunction peripheral thereof, and more particularly, to a paper dust removing member of a paper transport roller.

[0002]

2. Description of the Related Art Conventionally, an image forming apparatus forms an electrostatic latent image on a photoreceptor as a latent image carrier, visualizes the latent image with a developing unit, and transfers the latent image from the latent image carrier onto a sheet by a transfer unit. The visualized image is transferred, and the image is formed by fixing the image on paper by a fixing unit. The paper is loaded on a paper feed cassette and sent out one by one by a paper feed roller. At this time, the paper is rubbed,
Paper dust is generated. The fluff and the generated paper dust adhere to a paper transport roller provided in the paper transport path, a transfer roller as a transfer unit, or a photoconductor. The sticky fluff and paper dust adhere as a low-resistance substance and disturb the latent image on the photoreceptor, especially in an environment of high humidity.

In order to solve such a problem, in an "image forming apparatus" disclosed in Japanese Patent Application Laid-Open No. H11-52641, a paper feed roller is provided near a transfer roller at a substantially central portion of a driven roller of a registration roller pair. A sheet cleaning roller having the same width or a wider width as that described above is arranged to remove fluffing and paper dust on a recording sheet (paper) generated by contact of a paper feed roller. However, in consideration of the rubbing between the sheet and the conveyance guide plate, it is not sufficient to simply install the cleaning roller at a position corresponding to the sheet feeding roller, and it is desirable that the cleaning effect can be obtained over the entire surface of the sheet. Also, in this case, the amount of paper dust generated in the portion corresponding to the paper feed roller is larger than that in the other portions. It is necessary to prevent leakage from the removing means and outflow to the downstream side in the sheet transport direction.

On the other hand, in a "paper dust removing unit of an image forming apparatus" disclosed in Japanese Patent Application Laid-Open No. 6-336348, a paper dust removing unit is provided on a metal roller side of a registration roller pair including a metal roller and a rubber roller. The paper dust removing blade of the paper dust removing unit comes into close contact with the metal roller to remove the paper dust attached to the metal roller. In the conventional image forming apparatus, of the pair of registration rollers including the metal roller and the rubber roller as described above, the metal roller is located on the photoconductor (image surface) side, and the paper dust is removed on the metal roller side. Providing the means was effective in removing paper dust on the image surface of the paper. However, in some recent apparatuses, a roller located on the photoreceptor side is configured by a roller made of an elastic body such as rubber, and a paper dust removing unit having a configuration in which a blade is brought into contact with a conventional roller is used. This is inappropriate because the blades bite into the elastic body, causing problems such as generation of noise and entangling.

[0005]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention can continuously obtain an effect of removing paper dust adhered to a paper conveying roller, and can make a paper made of an elastic material such as rubber. An object of the present invention is to provide an image forming apparatus including a paper dust removing unit that can be applied to a transport roller.

[0006]

According to one aspect of the present invention, there is provided a paper feed cassette for loading paper, a paper feed roller for feeding paper from the paper feed cassette, and An image forming apparatus, comprising: an image carrier; and a transfer unit configured to transfer an image formed on the latent image carrier to the sheet, wherein a transfer position between the latent image carrier and the transfer unit is higher than a transfer position. An image forming apparatus is provided in which a plurality of paper dust removing members are provided on the circumference of a paper transport roller positioned upstream in the paper transport direction. According to a second aspect of the present invention, there is provided a paper feed cassette for loading paper, a paper feed roller for feeding paper from the paper feed cassette, a latent image carrier, and an image formed on the latent image carrier. An image forming apparatus having a transfer unit that transfers a sheet to the sheet, wherein a circumference and a shaft of a sheet conveyance roller positioned upstream in a sheet conveyance direction from a transfer position between the latent image carrier and the transfer unit. An image forming apparatus provided with a plurality of paper dust removing members in the direction. According to a third aspect of the present invention, there is provided the image forming apparatus according to the first or second aspect, wherein the paper dust removing member includes a foam and an elastic member for pressing the foam against a sheet conveying roller. I do. According to a fourth aspect of the present invention, in the image forming apparatus according to the third aspect, the paper transporting roller is a registration roller, and a roller formed of an elastic member in the registration roller pair is provided on the latent image carrier side. In the configuration located
An image forming apparatus is provided in which a plurality of the paper dust removing members are provided on a roller formed of the elastic body. According to a fifth aspect of the present invention, in the image forming apparatus according to any one of the first to fourth aspects, at least one of the plurality of paper dust removing members provided on the circumference of the paper transport roller is attached and detached. An image forming apparatus that can be used.

[0007]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic configuration diagram of a sheet feeding unit and an image forming unit of the image forming apparatus according to the present invention. From the paper (S) loaded in the paper feed cassette (1), only the uppermost paper is fed one by one by the paper feed roller (2) and the separation pad (3). The paper that has reached the registration rollers (4a, 4b) is sent to the photosensitive member (5), which is a latent image carrier, after the leading edge thereof is aligned, and is transferred to the transfer roller (6), which is a transfer unit.
An image is formed at the nip portion. Here, the paper feed roller (2) is installed at the center of the paper (S) in the transport direction. However, when the sheet is conveyed based on the end face of the sheet (S), the sheet may not be at the center. The registration rollers (4a, 4a,
b) is a roller having a length equal to or greater than the maximum paper width (normally corresponding to A3 vertical feed) in the present embodiment. The material of the roller 4a used as the driving roller includes a rubber roller (with a metal core), a metal roller coated with a high friction resin, and the like. The material of the driven roller 4b that rotates is a metal roller, a resin roller, a rubber roller, or the like. Further, there is a roller in which these rollers are provided separately.

According to the image forming apparatus of the present invention, a plurality of paper dusts are removed on the circumference of a paper transport roller located on the upstream side in the paper transport direction from the transfer position where the image on the photoreceptor (5) is transferred onto the paper. A member is provided. FIG. 2 is a diagram illustrating a configuration in which a paper dust removing member is provided on a driving roller of a registration roller. Here, the registration roller has a configuration in which a rubber roller is used as the driving roller (4a) and a metal roller is used as the driven roller (4b) on the same side (image surface) as the photoconductor (5). The drive roller (4a) has a first
Paper dust removing member (10) and second paper dust removing member (1)
1) is provided. The paper dust adhering to the surface of the drive roller (4a) is first blocked by the first paper dust removing member (10), and subsequently, the paper dust on the surface of the drive roller (4a) that has not been removed is removed from the second paper dust. It is configured to be blocked by the removing member (11). With such a configuration, paper powder adhering to the drive roller (4a) is removed by rubbing due to contact between the paper (S) and the paper feed roller (2) or rubbing due to contact with the conveyance guide plate, and the photosensitive drum is exposed to light. The surface of the body (5) can be prevented from being soiled by paper dust.

A paper dust removing member (10, 11) as described above.
Is not limited to the drive roller (4a) of the registration roller, but may be, for example, a paper transfer roller (12) in FIG. It can be installed on a paper transport roller located on the upstream side in the transport direction. However, the photoconductor (5)
In order to more effectively prevent the surface from being stained, the paper transport roller on which the paper dust removing members (10, 11) are installed is located on the same side as the photoconductor (5) of the registration roller located immediately before the transfer position. Most preferably, the driving roller (4a) is located.

The structure of the paper dust removing member according to the present invention is as follows. As shown in FIG. 2, the second paper dust removing member (11) includes a foam (11) at the tip of the elastic body (11a).
b) is attached to a part of the main body frame (7). The paper dust removing member (11) is attached to the main body frame (7) by bonding with double-sided tape, screwing, push rivets, or the like.
Further, as the elastic body (11a), a film made of a resin such as PET, a SUS thin plate, or the like can be used. As the foam (11b), foamed polyurethane, foamed CR, or the like can be used, and a driving roller (4
A material that has a low coefficient of friction is desirable in order to be resistant to abrasion with a) and to reduce noise. Elastic body (1
It is common to use a double-sided tape or an adhesive for joining the foam 1a) and the foam 11b. Furthermore, it is desirable that the second paper dust removing member (11) is mounted such that the end contacting the drive roller (4a) faces upward. Thereby, paper dust accumulated on the paper dust removing member (11) is easily separated from the drive roller (4a).

The main structure of the first paper dust removing member (10) is the same as that of the above-mentioned second paper dust removing member (11). The difference is that the first paper dust removing member (10) is attached to a part of the main body frame (7) by a detachable bracket (9). Bracket (9)
As an example of the attachment method, a method using a clip (8) as shown in FIGS. 2 and 3 is exemplified, but the method is not limited to this. With such a detachable configuration, when paper dust accumulates on the first paper dust removing member (10), it can be removed and cleaned together with the bracket (9). Thereby, the paper dust removing effect can be continuously obtained.

As described above, by providing a plurality of paper dust removing members on the circumference of the driving roller (4a), one of them can be provided only in a place where a large amount of paper dust is generated. For example, a central portion where the paper feed roller (2) is located is cited as an example. A first paper dust removing member (10) is arranged at a central portion where a large amount of paper dust is likely to be generated, and the paper dust is efficiently removed, and the accumulated paper dust is removed together with the bracket (9) for cleaning. The paper dust removing effect can be maintained.

FIG. 2 shows an example in which two paper dust removing members are provided. However, as shown in FIG.
a) A configuration in which three or more locations are provided on the circumference may be employed. If there are many places where paper dust occurs,
As shown in (1), a plurality of paper dust removing members may be provided in the axial direction of the driving roller (4a).

[0014]

As described above, according to the present invention, the foam is formed on the circumference of the paper transport roller located on the upstream side in the paper transport direction from the transfer position where the image on the photosensitive member is transferred onto the paper. By providing a plurality of paper dust removing members including an elastic member that presses the foam against the paper carrying roller, the paper dust adhered to the paper carrying roller can be reliably removed, and the removing effect can be continuously obtained. It is possible to provide a simple image forming apparatus. It is particularly effective to install the paper dust removing member on the drive roller of the registration roller. Even in a registration roller in which the drive roller is made of an elastic body such as rubber, the configuration of the paper dust removal member allows
It is possible to provide an image forming apparatus that removes paper dust attached to a driving roller and prevents the surface of a photoconductor from being stained with paper dust.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a sheet feeding unit and an image forming unit of an image forming apparatus according to the present invention.

FIG. 2 is a diagram illustrating a configuration in which a paper dust removing member is provided on a driving roller of a registration roller.

FIG. 3 is a diagram illustrating a method of attaching a bracket of a detachable paper dust removing member.

FIG. 4 is a diagram in which a plurality of paper dust removing members are arranged on a circumference of a driving roller.

FIG. 5 is a diagram in which a plurality of paper dust removing members are arranged in an axial direction of a driving roller.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 paper feed cassette 2 paper feed roller 3 separation pad 4a drive roller 4b driven roller 5 photoreceptor 6 transfer roller 7 body frame 8 clip 9 bracket 10 first paper dust removing member 11 second paper dust removing member 11a elastic body 11b Foam 12 Paper transport roller 13, 14 Paper dust removing member S Paper

Claims (5)

[Claims] 1. A paper feed cassette for loading paper, a paper feed roller for feeding paper from the paper feed cassette, a latent image carrier, and an image formed on the latent image carrier is transferred to the paper. An image forming apparatus having a transfer unit that performs a transfer operation between the latent image carrier and the transfer unit. An image forming apparatus comprising a plurality of image forming apparatuses. 2. A paper feed cassette for loading paper, a paper feed roller for feeding paper from the paper feed cassette, a latent image carrier, and an image formed on the latent image carrier is transferred to the paper. An image forming apparatus having a transfer unit that performs paper transfer along a circumference and an axial direction of a sheet conveyance roller positioned upstream in a sheet conveyance direction from a transfer position between the latent image carrier and the transfer unit. An image forming apparatus comprising a plurality of removing members. 3. The image forming apparatus according to claim 1, wherein the paper dust removing member includes a foam and an elastic member that presses the foam against a paper conveying roller. . 4. The image forming apparatus according to claim 3, wherein the paper transport roller is a registration roller, and a roller formed of an elastic member among the registration roller pair is located on the latent image carrier side. An image forming apparatus, wherein a plurality of the paper dust removing members are provided on a roller composed of the elastic body. 5. The image forming apparatus according to claim 1, wherein at least one of the plurality of paper dust removing members provided on a circumference of the paper transport roller is detachable. An image forming apparatus comprising: