JPS60230680A - Image forming device - Google Patents

Abstract

PURPOSE:To prevent scattering of removed brush hair into a machine with simple constitution by disposing a sponge member which rubs the surface of an image carrying body on the down stream side of a conductive fur brush. CONSTITUTION:The sponge member 15 which rubs the surface of a photosensitive body is provided on the down stream side of a conductive brush 8 of an image forming device. The member 15 is positioned by means of a double- coated adhesive tape, etc. to the recess provided to a cap 7 and is further grasped and attached by an electrifier 2. The photosensitive body 2 rubs with the conductive brush hair 10 of the cleaning brush 8 rotating in the direction opposite to the rotating direction of the body 2 in a cleaning position B, by which the remaining toner on the body is cleaned. The removed and cut conductive brush hair 10 is carried to the down stream side but is thoroughly dammed up by the sponge member 15, by which the hair is prevented from scattering to the outside of a cleaning device 5.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to an image forming apparatus having a conductive bristle brush that rubs the surface of a photoreceptor.

[Prior art and its problems]

In conventional electrophotographic copying machines, a toner image formed on a photoreceptor by a known electrophotographic process is transferred onto transfer paper by a transfer device, but at this time, 100% of the toner image on the photoreceptor is transferred onto the transfer paper. Instead of 9 usually 20-40%
A certain amount of toner remains untransferred on the photoreceptor. Therefore, it is necessary to remove the toner remaining on the photoreceptor after transfer so as not to affect the next new process, and a cleaning device is provided for this purpose.

A fur brush cleaning device is known as this cleaning device. In this method, a rotating conductive bristle brush to which a bias is applied is rubbed against the surface of the photoreceptor to remove residual toner on the photoreceptor. However, bristle brushes are constantly subjected to sudden bending stress, and when used for long periods of time, hair brushes may come off or break.
The removed or cut brush hairs are carried downstream as the photoreceptor rotates, causing various problems.

For example, it may adhere to the wires in the charger and cause abnormal discharge, it may enter the developing device and cause partial image defects, it may adhere to the transfer paper and make unsightly copies, and it may also adhere to the downstream side of conveyance. For example, it adheres to the heat roll of a certain fuser and contaminates it. However, it is difficult due to the structure of the bristle brush to completely eliminate hair removal and cutting.

Therefore, a member is required to prevent the removed brush bristles from being transported and scattered inside the machine. Conventionally, when cleaning fur brushes, it has been widely used to attach Mylar film, etc. to prevent toner from scattering.
This effect only prevents toner scattering, and no matter how strongly the Mylar film is brought into contact with the photoconductor, it has no effect at all in blocking the removed brush bristles, and on the contrary, it gradually damages the photoconductor. It was not possible to prevent the removed brush hair from scattering into the cabin.

[Purpose of the invention]

SUMMARY OF THE INVENTION In view of the above-mentioned conventional drawbacks, it is an object of the present invention to provide an image forming apparatus that has a simple structure and prevents removed brush hair from scattering inside the machine.

[Key points of the invention]

In order to achieve the above object, the present invention provides an image forming apparatus having a conductive bristle brush that rubs the surface of an image carrier.
The present invention is characterized in that a sponge member for rubbing the surface of the image carrier is disposed downstream of the conductive bristle brush.

[Embodiments of the invention]

Embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 1 is a block diagram of an image forming apparatus showing an embodiment of the present invention.

A photoreceptor 1 serving as an image carrier is rotatably provided in the direction of the arrow shown in the figure, and a charger 2.
Transfer device 3. Static elimination lamp 4. Cleaning devices 5 are arranged in sequence, and furthermore, an exposure device, a developing device, a fixing device, and a paper feeding device (not shown) are arranged at predetermined positions.

In the cleaning device 5, a cleaning holder 981, a collection roll 11, and a blade 12 are disposed inside a cleaner assembly consisting of a casing 6 and a lid 7 while maintaining their respective positional relationships. As shown in FIG. 2, the cleaning brush 8 and recovery roll 11 are rotationally driven by gears 1B and 19 attached to respective shaft portions 16 and 17 meshing with a drive gear 20.

The configuration of the cleaning brush 8 is as follows.

As shown in FIGS. 3 and 4, the warp threads 21. Conductive brush bristles 10 are bundled and woven into a base fabric consisting of weft threads 22, and these are adhered to the conductive core 9 via a conductive adhesive layer 23, so that the conductive core 9 and the conductive brush bristles are bonded to each other through a conductive adhesive layer 23. There is complete electrical continuity with IO. Brush weaving methods include ■ weaving and W weaving, and in the ■ weaving shown in Figure 3, a bundle of conductive brush bristles 10 is tied and fixed at only one place on a base fabric made up of warp threads 21 and weft threads 22. It is
In addition, the W weave shown in FIG. 4 has conductive brush hairs 1 on the base fabric.
A bundle of 0 is tied and fixed in three places. The material of the conductive brush bristles 10 is desirably a conductive rayon material, especially a conductive rayon material with a specific resistance of 107 to 10" Ω crn.
A bundle of ~300 pieces is used. The density of the brush bristles 10 is desirably 150,000 bristles/1 nch' to 220,000 bristles/1 nch'. The conductive core 9 may be a general drawn or extruded tube made of aluminum or stainless steel, or a paper tube which has been appropriately conductive treated. The material of the collection roll 11 is aluminum, stainless steel, etc.

Further, the blade 12 is clamped and fixed between blade holders 13 and 14, and its tip end portion is in pressure contact with the collection roll 11, and is made of a rubber-like elastic material with a hardness of 60° to 80°, particularly wear resistance, ozone resistance, etc. From this point of view, urethane rubber is used.

In this embodiment, the amount of interference of the conductive brush bristles 10 with the photoreceptor 1 and collection roll 11 is t! +, (12 (see Figure 5) is β+=1.0~2.0m, jl!shi=1.0~1
．． 5 cranes, and the length h of the brush bristles 10 (FIGS. 3 and 4) is h=4 to 6111. on the other hand.

A sponge member 15 that rubs the surface of the photoreceptor 1 is provided downstream of the cleaning brush 8 .

In this embodiment, the sponge member 15 is positioned in a recess provided in the lid 7 using double-sided adhesive tape or the like.

Furthermore, it is attached while being clamped by a charger 2.

For example, the standard cell size of the sponge member 15 is 40.
A foamed sponge of 1 nch' or more is used.

Next, the operation of the image forming apparatus having the above configuration will be explained.

As the photoreceptor weight rotates, the surface of the photoreceptor 1 is first uniformly charged by the charger 2, and then an optical image of the original is exposed to form an electrostatic latent image, and this electrostatic latent image is developed by the developer. and becomes a toner image. At a transfer position A, the toner image formed on the photoreceptor 1 is transferred onto a transfer paper P fed from a paper feeding device by the electrostatic attraction action of the transfer device 3.

The transfer paper P onto which the toner image has been transferred is separated from the photoreceptor 1 by a separating means (not shown), and the image is fixed by a fixing device. The toner remaining untransferred on the photoconductor 1 after the transfer is irradiated with light by the static elimination lamp 4 as the photoconductor 1 rotates in the direction shown. Due to this light irradiation, the residual charge on the photoreceptor 1 during the charging and transfer process is rapidly reduced, and the electrostatic adhesion between the surface of the photoreceptor 1 and the residual toner is almost eliminated, making it easier for the residual toner to separate from the photoreceptor 1. .

Next, at the cleaning position B, the photoreceptor 1 rubs against the conductive bristles 10 of the cleaning brush 8 rotating in the opposite direction to the photoreceptor 1, and the residual toner on the photoreceptor 1 is cleaned. A bias having a polarity opposite to that of the residual toner is applied to the brush bristles 1O through the conductive core 9.

This bias is a low bias value of about 50 to 200 square meters. Therefore, the residual toner on the photoreceptor 1 is removed from the photoreceptor 1 by physical scraping by the rubbing of the brush bristles 10 and by the action of electrostatic attractive force by applying a bias.

The residual toner that has moved from the photoconductor 1 to the brush bristles 10 is removed from the collection roll 1 as the cleaning brush 8 rotates in the direction shown in the figure.
It is carried to the point of contact with 1.

Since a bias voltage of the same polarity as the bias applied to the brush bristles 10 and 200 to 500 mm higher than this is applied to the collection roll 11, the residual toner retained on the brush bristles 10 is transferred to the collection roll 11. It moves onto the second collection roll 11 due to the electrostatic attraction force due to the bias and the physical sliding force between the brush bristles 10 and the collection roll 11. The residual toner that has moved onto the collection roll 11 is scraped off by the blade 12.

In the cleaning process, as described above, since the cleaning brush 8 is slidingly rotating in the opposite direction to the photoreceptor 1 at the rubbing portion with the photoreceptor 1, the conductive bristles 10 are constantly subjected to sudden bending stress. When used for a long period of time, the binding force between the conductive brush bristles 10 and the base fabric may become loose, causing hair loss or the conductive bristles 10 to break off at their bent portions. The conductive brush bristles 10 that have been removed or cut in this way are carried to the downstream side as the photoreceptor 1 rotates. It is completely blocked by the sponge member 15. Therefore, the conductive brush bristles 10 are completely blocked by the cleaning device 5.
It will not scatter to the outside and enter the charger 2, transfer device 3, etc. and cause trouble.

In this embodiment, a foamed sponge with a standard cell size of 40 cells/inch or more is used as the sponge member 15. According to this, even if it comes into strong contact with the photoreceptor 1, hair removal can be performed without damaging the photoreceptor 1 at all. However, the material of the sponge member 15 is not particularly limited to this. [Effects of the Invention] As explained above in detail, the image forming apparatus of the present invention has a simple structure, does not damage the surface of the photoreceptor at all, and completely prevents removed brush bristles from scattering inside the damming machine, so that the image forming apparatus of the present invention can reduce the amount of hair removed. A stable image can be formed without being affected by brush bristles.

[Brief explanation of the drawing]

Fig. 1 is a block diagram showing an embodiment of the present invention, Fig. 2 is a perspective view of the main parts of the present invention, Figs. 3 and 4 are block diagrams showing how to weave conductive brush bristles, and Fig. 5. FIG. 2 is a configuration diagram showing the positional relationship between a photoreceptor, a cleaning brush, and a collection roll. 1... Photoreceptor, 5... Cleaning device, 8.
・Cleaning brush. 10... Conductive brush bristles, 15... Sponge member. Patent Applicant: Casio Computer Co., Ltd. Yoshiyuki Osuga, Patent Attorney, ID Co., Ltd.

Claims (2)

[Claims] (1) An image forming apparatus having a conductive bristle brush that rubs the surface of the image carrier, characterized in that a sponge member that rubs the surface of the image carrier is disposed downstream of the conductive bristle brush. Image forming device. (2) The standard cell size of the sponge member is 40 pieces/
The image forming apparatus according to claim 1, wherein the image forming apparatus is a foamed sponge of 1 nch' or more.