JPH09114202A - Toner elimination material and toner elimination device for contact type electrostatic charge roller - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a toner elimination material which can eliminate toner left at the recessed part of the surface of a contact type electrostatic charge roller without damaging the surface thereof and which can be used extending over a long term without causing clogging. SOLUTION: This toner elimination device is made to face the contact type electrostatic charge roller R in contact with the photoreceptor drum of an image forming device. The toner elimination device is provided with the elimination material 14 at the end part on the roller R side. The material 14 is set in pressure-contact with the roller R. The material 14 is constituted of a base material 14a and abrasive grains 14b scattered and stuck to the contact surface of the base material 14a. The base material 14a is formed of foamable chloroprene rubber having hardness of 25 deg.. Therefore, the material 14a is porous and provided with elasticity. The size of the grains 14b is formed smaller than the surface roughness of the roller R. The grains 14b are also provided in the recessed part opened on the surface of the base material 14.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION A contact charging roller incorporated in an image forming apparatus such as a copying machine, a facsimile machine, a printer, or the like contacts with the photosensitive drum to rotate in order to charge the photosensitive drum. At this time, the residual toner on the photosensitive drum adheres to the contact charging roller and accumulates in the recesses on the surface of the contact charging roller, causing charging failure and causing image deterioration such as white spots. The present invention relates to such a toner removing material and a removing device using the same.

[0002]

2. Description of the Related Art An example of a conventional toner removing device is shown in FIGS. The toner removing device 1 is provided so as to face a charging roller R that contacts the photosensitive drum D in order to charge the photosensitive drum D. The removing material 2 of the toner removing device 1 contacting the charging roller R is a base material 2a made of sponge felt.
The nonwoven fabric 2b is bonded to the surface of the. Then, when the charging roller R rotates, the toner T attached to the surface is wiped off by the removing material 2. 8 and 9 show another conventional toner removing device. In this toner removing device 3, the base end of an rotatably pivoted arm plate 4 is connected to a DC solenoid 5 via a spring 6, while
The removing material 7 is fixed to the free end. The removing material 7 can be brought into and out of contact with the contact charging roller R by the operation of the DC solenoid 5. In the removing material 7 of the toner removing device 3, abrasive paper 7b is adhered to a base material 7a made of sponge. Then, when the charging roller R rotates while the removing material 7 is in contact with the toner T, the surface of the charging roller R is slightly scraped by the polishing paper 7b, and the toner T attached is removed.

[0003]

In the former one of the above-mentioned conventional toner removing devices, the removing material 2 is the charging roller R.
The toner T accumulated there cannot be wiped off because it does not reach the concave portion of the surface of the. In contrast, the latter is shown in FIG.
As shown in (a) and (b), such toner T can be removed, but as shown in FIG. 11, shavings of the contact charging roller R and toner T are provided between the abrasive grains 7c of the abrasive paper 7b.
Foreign matter such as will enter and cause clogging, and its function cannot be maintained for a long time. FIG.
As shown in (3), the surface of the contact charging roller R is deeply shaved by the abrasive grains 7c, and a charging failure portion (hatched portion in the drawing) is generated in a streak shape, and a streak-shaped image abnormality corresponding thereto is generated.
Therefore, the present invention provides a toner removing material for a contact charging roller and a toner removing device which can remove the toner in the concave portion of the contact charging roller R without damaging the surface thereof, can be used for a long period of time without causing clogging. The task is to do.

[0004]

In order to solve the above-mentioned problems, in the first invention, a removing member 14 for the toner T adhering to the surface of the contact charging roller R that contacts the photosensitive drum D to charge it is provided. , A base material 14a made of a porous foaming resin having elasticity that comes into pressure contact with the contact charging roller R
And an abrasive 14b which is adhered to the surface of the base material 14a and abrades the surface of the contact charging roller R. Second
In the invention described above, abrasive grains 14c smaller than the surface roughness of the contact charging roller R are dispersed in the abrasive 14b. Third
In the invention, the toner removing material 14 can be selectively contacted with and released from the contact charging roller R.

[0005]

Embodiments of the present invention will be described with reference to the drawings. In FIG. 1 and FIG. 2, a contact charging roller R for charging the photosensitive drum D in the image forming apparatus is provided close to the photosensitive drum D. The toner removing device 10 is provided facing the contact charging roller R. The toner removing device 10 has an arm plate 11 whose center portion is rotatably attached. The base end of the arm plate 11 is connected to the DC solenoid 12 via a spring 13. By energizing the DC solenoid 12, the arm 11 is rotationally displaced within a certain range. A removing material 14 is fixed to the free end of the arm 11. The removing material 14 is brought into pressure contact with the contact charging roller R at a position rotated counterclockwise in the drawing. As shown in FIG. 3A, the removing material 14 is used as the base material 1
4a and abrasive grains 14b scattered and adhered to the contact surface of the base material 14a. The base material 14a has a hardness of 25
It is made of expanded chloroprene rubber, and is therefore porous and elastic. The abrasive particles 14b are contact charging rollers R
The grain size is smaller than the roughness of the surface. The abrasive grains 14b are
As shown in FIG. 3 (b), it is also adhered to the inside of the recess opening in the surface of the base material 14.

When the contact charging roller R rotates together with the photosensitive drum D while the removing material 14 of the toner removing device 10 is in contact, the toner T and other foreign matters on the surface of the contact charging roller R are attracted to the removing material 14. . That is, the removing material 14 is
From the state shown in FIG. 4A, the solenoid 12 and the spring 1
Rotation of the arm plate 11 via the contact charging roller R
Then, it comes into contact with the surface while being pressed under pressure and elastically deformed as shown in FIG. When the contact charging roller R rotates in this state, the abrasive particles 14b slightly scrape off the surface of the contact charging roller R to remove the toner T adhering thereto. At this time, the toner T accumulated in the concave portion on the surface of the contact charging roller R is also removed by the close contact of the removing material 13. Since the particle size of the polishing particles 14b is smaller than the roughness of the surface of the contact charging roller R, the surface is ground substantially uniformly without scratches as shown in FIG. 3 (c). Further, after the removal, the surface of the removing material 13 is changed from the state shown in FIG. 5 (a) to the concave portion on the surface of the base material 14 as shown in FIG. They do not adhere very much to the outside, so they do not clog between the abrasive grains.

[0007]

As described above, in the present invention, the toner accumulated in the concave portion of the surface of the contact charging roller R can be removed without causing clogging of the contact surface, and the function is maintained for a long time. be able to. In addition, at that time, the surface of the contact charging roller R is not scratched in a streak shape, and it is possible to prevent deterioration of image quality due to charging failure, and it is possible to maintain a good image state for a long period of time.

[Brief description of the drawings]

FIG. 1 is a side view of a toner removing device according to the present invention.

FIG. 2 is a front view of a toner removing device.

FIG. 3A is a front view of a toner removing material, and FIG. 3B is a partially enlarged view.

FIG. 4A is a partially enlarged view of the toner removing material before contact,
(B) is a partially enlarged view of the toner removing material at the time of contact, and (c) is a partially enlarged view of the toner removing material after the toner is removed.

5A is a partially enlarged view of the toner removing material before toner removal, and FIG. 5B is a partially enlarged view of the toner removing material after toner removal.

FIG. 6 is a side view of a conventional toner removing device.

FIG. 7 is a partially enlarged view of the toner removing material.

FIG. 8 is a side view of another conventional toner removing device.

FIG. 9 is a front view of the toner removing device.

10A is a partially enlarged view of a toner removing material before toner removal, and FIG. 10B is a partially enlarged view of a toner removing material after toner removal.

FIG. 11 is an enlarged view of the abrasive after removing the toner.

FIG. 12 is an enlarged view of the contact charging roller after toner removal.

[Explanation of symbols]

 10 Toner Removal Device 11 Arm Plate 14 Removal Material 14a Base Material 14b Abrasive Grains

Claims (3)

[Claims] 1. A material for removing toner adhering to the surface of a contact charging roller that contacts a photosensitive drum and charges the photosensitive drum, which is made of a porous foaming resin having elasticity that comes into pressure contact with the contact charging roller. A toner removing material for a contact charging roller, comprising a base material and an abrasive material adhered to the surface of the base material and polishing the surface of the contact charging roller. 2. The toner removing material for a contact charging roller according to claim 1, wherein the abrasive is made by scattering abrasive particles smaller than the surface roughness of the contact charging roller. 3. A toner removing device for a contact charging roller, wherein the toner removing material according to claim 1 can be selectively brought into contact with or separated from the contact charging roller.