JPH07209968A - Destatixizer - Google Patents

Abstract

PURPOSE:To secure a linear and sure electrostatic charge removing area in accordance with the edge part of an original e.g. by linearly forming the upstream side part of a light irradiation area to the surface of a photosensitive body in the rotational direction of the photosensitive body over the axial center part of the photosensitive body in respect to a destaticizer to be used for an image forming device such as a copying machine. CONSTITUTION:A light shielding plate 13 is constituted from the downstream side edge part of a glid plate 13 constituting an electrifier 12 in the rotational direction (an arrow 10 direction) of a photosensitive drum 7 and the upstream side parts of irradiation areas 9a of light from plural light emitting elements 9 in the arrow 10 direction are linearly divided over the axial center direction (an arrow 8 direction) of the drum. Consequently light irradiation areas to the surface of the drum 7 can be linearly formed over the axial center direction and a charge removing area is also linearly and surely formed correspondingly to the linear light irradiation area.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a static eliminator used in an image forming apparatus such as a copying machine.

[0002]

2. Description of the Related Art Generally, in this type of image forming apparatus, an electrostatic latent image is formed on a photosensitive drum 1 (see FIG. 3) by exposing and scanning an original placed on an original table with an optical system. Is formed. Then, the electrostatic latent image is visualized by developing the surface of the photosensitive drum 1 with a developing device. By the way, in this case, in order to prevent unnecessary adhesion of toner to a region (predetermined region) other than a region corresponding to the document on the photosensitive drum 1 prior to the developing process by the developing device, the predetermined region is prevented. Is removed by the static eliminator 2. That is, the photosensitive drum 1
The surface of the photosensitive drum 1 uniformly charged by a charger (not shown) located on the upstream side in the direction of rotation (direction of arrow 3) of FIG. The charges in the other predetermined regions are removed. As shown in FIG. 1, the static eliminator 2 is provided with a plurality of light emitting elements 4, 4, ... Arranged side by side at appropriate intervals in the axial direction of the photoconductor drum 1. Light emitting element 4,
The charges are removed by irradiating the surface of the photosensitive drum 1 with light from 4 ,.

[0003]

By the way, in the static eliminator 2, in order to irradiate light over the entire area of the photosensitive drum 1 in the axial direction, one of the circular irradiation areas 4a by the light emitting elements 4 is formed. The portions are overlapped with each other and are continuous in the axial direction of the photosensitive drum 1. Therefore, the edge portion formed by these irradiation areas has a wave shape continuous in the axial direction of the photoconductor drum 1, and linear and clear charge removal is performed corresponding to the edge portion of the light irradiation area. The area cannot be secured. Therefore, the present invention has been devised in view of the above circumstances, and the irradiation area of the light on the surface of the photosensitive drum 1 is made linear along the axial direction thereof, and is linear in correspondence with the edge portion of the document. The purpose of the present invention is to provide a static eliminator capable of ensuring a static and clear static erasing region.

[0004]

In order to achieve the above-mentioned object, the main means adopted by the present invention is, as its gist, a plurality of means arranged in parallel in the axial direction of the photoconductor at appropriate intervals. A static eliminator comprising a light emitting element for irradiating light from the plurality of light emitting elements onto the surface of the photoconductor to remove electric charges in a predetermined region of the surface of the photoconductor charged by a charger, It is arranged on the upstream side in the rotation direction of the photoconductor, partially blocks the light from the plurality of light-emitting elements, and defines a portion of the irradiation area on the surface of the photoconductor by the light on the upstream side in the rotation direction of the photoconductor. The static eliminator according to the present invention is provided with a light shielding plate that linearly partitions the photosensitive member in the axial direction.

[0005]

In the static eliminator according to the present invention, the light irradiation area of the plurality of light emitting elements is linearly divided in the axial direction of the photoconductor by the action of the light shielding plate. It is possible to secure a linear and clear charge elimination region depending on the portion.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments embodying the present invention will be described below with reference to the accompanying drawings for the understanding of the present invention. The following embodiments are examples of embodying the present invention and are not intended to limit the technical scope of the present invention. 1 is a perspective view of a main portion of a static eliminator according to an embodiment of the present invention, and FIG. 2 is a perspective view of a main portion of a static eliminator according to another embodiment of the present invention. In the static eliminator 5 according to this embodiment, as shown in FIG. 1, a plurality of light emitting elements 9, 9, ... Are provided in the casing 6 at appropriate intervals in the axial direction of the photosensitive drum 7 (direction of arrow 8). It is installed side by side. Then, the irradiation areas 9a, 9 by the light from the plurality of light emitting elements 9, 9 ,.
.. are connected so that both end portions in the direction of the arrow 8 overlap each other, and cover the entire surface of the photosensitive drum 1 in the axial direction. A light shielding plate 11 is provided on the upstream side of the plurality of light emitting elements 9, 9, ... In the rotation direction (direction of arrow 10) of the photosensitive drum 7. The light blocking plate 11 includes a plurality of light emitting elements 9, 9,
The effect of partially blocking the light from the ... Eggplant In this embodiment, the edge portion of the grid plate 13 constituting the wire electrode type charger 12 on the downstream side in the direction of the arrow 10 constitutes the light shielding plate 11. The static eliminator 5 according to this embodiment is configured as described above.

Therefore, when the charge of the predetermined area on the surface of the photoconductor drum 7 uniformly charged by the charger 12 is removed by using the charge removal device 5, the light irradiation area on the surface of the photoconductor drum 7 is removed. It is not linear in the axial direction, and for example, a linear and clear charge removal area can be secured in accordance with the edge portion of the document. By the way, here
The object for ensuring the linear charge removal area is not limited to the above-mentioned document edge portion,
For example, the static eliminator can be applied even when static elimination is performed corresponding to a predetermined designated area in a document and the edge portion thereof is clearly partitioned. FIG. 2 shows a static eliminator according to another embodiment having a light shielding plate 14 or 15 having the same function as the light shielding plate 11. That is, the light shielding plate 14 is provided by extending the lower end of the casing 6 on the upstream side in the direction of the arrow 10 so as to block each irradiation region 9a, and is shown by a solid line in the figure. On the other hand, the light-shielding plate 15 includes the charger 12
The lower end of the casing 16 on the downstream side in the direction of the arrow 10 is extended so as to block the irradiation region 9a, and is shown by a chain double-dashed line in FIG. In the static eliminator provided with the light shielding plate 14 or 15, as in the case of the static eliminator 5, the action of the light shielding plate 14 or 15 causes the light irradiation areas 9a, 9a, ... The upstream portion in the direction of arrow 10 can be made linear over the direction of arrow 8, and a linear and clear charge elimination region can be secured in accordance with the edge portion of the document.

[0008]

As described above, the present invention is provided with a plurality of light emitting elements arranged in parallel in the axial direction of the photoconductor at appropriate intervals, and the light from the plurality of light emitting elements is supplied to the photoconductor. A static eliminator that removes electric charges in a predetermined region of the surface of the photoconductor that is irradiated by the surface and charged by a charger, is disposed upstream of the plurality of light emitting elements in the rotation direction of the photoconductor, and is disposed from the plurality of light emitting elements. A light-shielding plate for partially blocking the light of the above and linearly partitioning a portion of the irradiation area on the surface of the photoconductor on the upstream side of the rotation direction of the photoconductor in the axial direction of the photoconductor. Since this is a characteristic static eliminator, it is possible to make the upstream side in the rotation direction of the photoconductor in the light irradiation area on the photoconductor surface linear along the axial direction of the photoconductor. Linear and clear corresponding to the part It is possible to secure a neutralizing region of the Do charge.

[Brief description of drawings]

FIG. 1 is a perspective view of a main part of a static eliminator according to an embodiment of the present invention.

FIG. 2 is a perspective view of a main part of a static eliminator according to another embodiment of the present invention.

FIG. 3 is a perspective view of a main part of a conventional static eliminator.

[Explanation of symbols]

 5 ... Static eliminator 6, 16 ... Casing 7 ... Photosensitive drum 9 ... Light emitting element 9a ... Irradiation area 11, 14, 15 ... Shading plate 12 ... Charger 13 ... Grid plate

Claims (2)

[Claims] 1. A photoconductor comprising a plurality of light emitting elements arranged in parallel in the axial direction of the photoconductor at appropriate intervals, and irradiating light from the plurality of light emitting elements onto the surface of the photoconductor to charge the same by a charger. In the static eliminator for removing charges in a predetermined area on the surface of the photoconductor, the static elimination device is arranged upstream of the plurality of light emitting elements in the rotation direction of the photoconductor and partially blocks light from the plurality of light emitting elements. A static eliminator provided with a light-shielding plate that linearly partitions a region on the surface of the photoconductor on the upstream side in the rotation direction of the photoconductor by light, in the axial direction of the photoconductor. 2. The static eliminator according to claim 1, wherein the light shielding plate is composed of an edge portion of the charger on the downstream side in the rotation direction of the photoconductor.