JPH1026916A - Image carrier cleaning device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent rugged flaw from occurring on the photosensitive surface of an image carrier and to suppress generation of stripes on the image to extend a life of the image carrier, by constituting a loop shaped fiber by bundling plural short fibers and specifying a ratio of a Denier number of this loop shaped fiber to the number of filaments of single fibers composing the loop shaped fiber. SOLUTION: Each fiber 5 of fur brush 2 is an insulating polyester fiber, and is attached to a fur brush main body 8 in a looped form, and one piece of the fiber 5 is composed by bundling plural single fibers 6. A ratio D/F of a Denier number D expressing a thickness of the fiber 5 to a filament number F expressing the number of the single fibers 6 is made 4<D/F<9, and a flocking fiber density of the fiber 5 is made 450 loops/in<2> or less. Consequently, a contact area between the tip of the fur brush 2 and a photosensitive surface 4 is wide, so that the surface 4 wears uniformly, and each fiber 5 becomes disentangled as time passes and each of the single fiber is brought into contact with the surface 4.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image carrier cleaning apparatus for an image forming apparatus such as an electrophotographic copying machine, a facsimile, a laser printer, and the like.

[0002]

2. Description of the Related Art A conventional cleaning apparatus of this kind is constructed in the same manner as the embodiment of the present invention shown in FIG. 1, and includes an image carrier 1 and a fur brush 2 which rubs the photosensitive surface of the image carrier 1. And a cleaning blade 3 pressed against the surface. In such a case, the image carrier 1 rotates in the direction of the arrow, and the toner 7 remaining on the photosensitive surface after the transfer step is formed.
Is scraped off with a fur brush 2, and the remaining toner is scraped off with a cleaning blade 3.

[0003]

However, such a fur brush 2 is usually made of one piece of polyester, nylon,
It is composed of loop-like single fibers such as rayon,
The tip portion scrapes off the photosensitive surface 4 of the image carrier 1 and causes the entire surface to be worn, thereby generating irregular flaws on the surface,
Variations in the thickness of the photosensitive surface due to the flaws cause local unevenness in the sensitivity of the photosensitive member, causing streaks on the image and shortening the life of the image carrier.

Accordingly, an object of the present invention is to solve the problems of the conventional image carrier cleaning device as described above,
An object of the present invention is to provide an image carrier cleaning device that does not cause flaws on the photosensitive surface of the image carrier by the fur brush, and therefore does not cause streaks on an image.

[0005]

In order to achieve the above object, the present invention is directed to a conventional image carrier cleaning apparatus as described above.
The fur brush has individual fibers in a loop shape. One loop fiber is formed by bundling a plurality of single fibers, and the denier number (D) of the loop fibers and the loop fibers are formed. The ratio (D / F) of the single fiber to the number of filaments (F) is 4 <D / F <9, and the invention according to claim 2 is the invention according to claim 1, wherein The flocking density of loop fibers is 450 per unit area.
Loop / square inch or less.

[0006]

In the image carrier cleaning apparatus of the present invention as described above, the toner remaining on the photosensitive surface of the image carrier after the transfer step is scraped off with a fur brush, similarly to this type of conventional cleaning apparatus. Further, the fur brush is scraped off by a cleaning blade. At this time, the fur brush has individual fibers in a loop shape, and one loop-like fiber is formed by bundling a plurality of single fibers, and the loop-like fiber is formed. The ratio between the denier number (D) and the filament number (F) of the single fiber, that is, the thickness (D / F) of the single fiber is
Since 4 <D / F <9, the contact pressure and frictional force between the tip of the fur brush and the surface of the image carrier decrease, and at the same time, the number of single fibers increases. And the photosensitive surface of the image carrier is not uniformly worn and scratched. Further, since the flocking density of the fibers is 450 loops / square inch per unit area, clogging due to residual toner between the fibers is prevented.

[0007]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. The difference between this embodiment and the conventional cleaning device is the configuration of the fur brush 2. The individual fibers 5 of the fur brush 2 are attached to the fur brush main body 8 in a loop shape as shown in FIG. 2 by an insulating polyester fiber.
As shown in the figure, the plurality of single fibers 6 are bundled.
The ratio of the denier number (D) indicating the thickness of the fiber 5 to the filament number (F) indicating the number of the single fibers 6, that is, the thickness (D / F) of the single fiber 6 is set to 4 <D / F <9. age,
The flocking density of the fiber 5 is represented by the number of loops per unit area (1 square inch), which is 450 loops / 1 square inch or less.

As described above, by forming the individual fibers 5 of the fur brush 2 into a loop, the contact portion between the tip of the fur brush 2 and the photosensitive surface 4 of the image carrier 1 has a width as shown in FIG. And the surface 4 is uniformly worn, and the individual fibers 5 are loosened over time.
The main body contacts the surface 4 of the image carrier 1.

Further, by reducing the thickness of the single fibers 6 as described above, the contact pressure between the fur brush 2 and the photosensitive surface 4 of the image carrier 1 is reduced, and the number of the single fibers 6 is increased. The contact area is increased and the surface 4
The occurrence of uneven flaws and streaks on an image can be reduced.

In FIG. 5, when a difference between the film thicknesses of the adjacent concave and convex portions of the photosensitive surface 4 of the image carrier 1 cut by the fur brush is Rmax, a halftone portion corresponding to the unevenness of the surface 4 is provided. In this invention, if Rmax after rotating the image carrier 1 for 100 hours is 1 μm,
Streaks on the image can be ignored.

FIG. 6 shows the thickness (D / F) of the single fiber 6.
Rmax after 100 hours of rotation is shown. When the flocking density is fixed at 300 loops / square inch, 250 D / 48F (D / F = 5.
Rmax by the brush of 2) becomes the smallest, and
It is improved compared to D / 24F (D / F = 10.4). D
When /F<3.5, Rmax becomes larger than before, but it is considered that this is because the residual toner is clogged between the fibers and the toner scrapes the photoreceptor. By using the fur brush 2 in which the thickness of the single fiber 6 is 4 <D / F <9, Rmax after 100 hours of use can be suppressed to 1 μm or less, so that the occurrence of streaks on the image is reduced. You can see that.

FIG. 7 shows Rmax according to the flocking density when the thickness of the single fiber 6 is fixed at 250 D / 48F, that is, D / F = 5.2.
(100 hours) change. The higher the flocking density, the more R
The maximum tends to be large, which is considered to be due to the fact that the residual toner is easily clogged between the fibers. Therefore, it can be seen that the unevenness flaws on the photosensitive surface 4 can be reduced by the brush 2 having 450 loops / square inch or less.

[0013]

As described above, the present invention provides a fur brush in which individual fibers are formed into a loop, and one loop-shaped fiber is formed by bundling a plurality of single fibers. (D) and the ratio (D / D) of the number of filaments (F) of the monofilament constituting the loop-shaped fiber
F) is 4 <D / F <9, and the thickness of the single fiber is thin, so that the contact pressure between the tip of each single fiber constituting the fur brush and the photosensitive surface of the image carrier and By reducing the frictional force, the wear of the tip of the single fiber is suppressed, and at the same time, the number of contact portions by the single fiber is increased, and the photosensitive surface of the image carrier is uniformly abraded while keeping the Rmax at or below a predetermined value. As a result, there is an effect that uneven scratches are not generated on the photosensitive surface of the image carrier, so that streaks on the image are suppressed, and the life of the image carrier is extended. In addition, the flock density of the looped fibers of the fur brush
Since it is 450 loops / square inch or less, clogging of the residual toner between the fibers is prevented, and furthermore, there is an effect that generation of a flaw on the surface of the image carrier can be effectively prevented.

[Brief description of the drawings]

FIG. 1 is a front view of an embodiment of the present invention.

FIG. 2 is an enlarged view of a part of the fur brush.

FIG. 3 is an enlarged perspective view of a part of one of the fibers.

FIG. 4 is an enlarged view showing a contact state between the image carrier and the fur brush according to the first embodiment.

FIG. 5: Surface roughness and ID of the image carrier after 100 hours of rotation
FIG.

FIG. 6 is a correlation diagram between D / F and a difference Rmax in film thickness.

FIG. 7 is a correlation diagram between a loop / square inch and a film thickness difference Rmax.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Image carrier 2 Fur brush 3 Cleaning blade 4 Photosensitive surface 5 Fiber 6 Single fiber 8 Brush body

Claims (2)

[Claims] 1. An image carrier cleaning apparatus for an electrophotographic image forming apparatus, comprising: an image carrier; a fur brush rubbing the surface of the image carrier; and a cleaning blade pressed against the surface. The brush has a loop shape in which individual fibers are looped. One loop-shaped fiber is formed by bundling a plurality of single fibers, and the denier number (D) of the loop-shaped fiber and the single fiber constituting the loop-shaped fiber The ratio (D / F) to the number of filaments (F) is 4 <D / F <
9. An image carrier cleaning device according to claim 9, wherein 2. The image carrier cleaning device according to claim 1, wherein the flocking density of the loop-shaped fibers is 450 loops / square inch or less per unit area.