JPH06250572A - Cleaning device for photo receptor drum - Google Patents

Abstract

PURPOSE:To prevent foreign matter from getting into round from lateral both outside parts of a cleaning blade with a simple structure, and more perfectly remove the foreign matter adhered to a photoreceplor drum by juxtaposing seal materials for removing the foreign matter adhered around both end parts of the photosensitive drum to the cleaning blade. CONSTITUTION:A cleaning blade 1 is elastically slid on a photoreceptor drum 20 in an area (sheet width Pw) slightly wider than the printing ensuring area A1 of the photoreceptor drum 20. Seal materials 3 are further slid in both lateral outside positions of the cleaning blade 1, or the position closer to the rotating direction of the photoreceptor drum 20 from the sliding position of the cleaning blade 1 in the non-printing area A2 of the photoreceptor drum 20. Thus, foreign matter leaked from both the lateral sides of the cleaning blade 1 and readhered to the non-printing area A2 of the photoreceptor drum 20 is captured by the seal materials 3. Thus, there is no possibility of the foreign matter being adhered to the circumferential surface of the photoreceptor drum 20 passed through a cleaning device 10.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cleaning device for a photosensitive drum in an electrophotographic image forming apparatus, and more particularly to the cleaning device having a cleaning blade.

[0002]

2. Description of the Related Art FIG. 3 is a conceptual diagram of an electrophotographic image forming apparatus. As shown in FIG. 3, in the electrophotographic image forming apparatus, the peripheral surface of the photosensitive drum 20 that is driven to rotate clockwise in the figure is precharged by the charger 30, and a light beam is emitted from the light source device 40. To form an electrostatic latent image, and then the developing device 50
Then, a step of developing the electrostatic latent image into a toner image and transferring the toner image onto the sheet P by the transfer device 60 is performed. Further, after a foreign matter such as toner or paper dust attached to the peripheral surface of the photoconductor drum 20 is removed by a cleaning device 10 provided in the latter stage of the transfer device 60, the photoconductor 70 is provided with an optical neutralizer 70.
The residual potential of 0 is eliminated, and the above steps are repeated again.

FIG. 4 is a front view showing an example of the construction of the cleaning device, and FIG. 5 is a vertical side view of the same.
As shown in FIG. 4, in this cleaning device 10, a cleaning blade 1 made of a flexible material such as silicon rubber or urethane rubber is supported by a holder 2 so that a tip surface 1a thereof projects obliquely downward. , In a region (corresponding to the paper width P _w in the illustrated example) slightly larger than the print-guaranteed region A ₁ of the photoconductor drum 20.
It is configured to elastically contact 0. Further, as shown in FIG. 5, in order to efficiently scrape off the foreign matter S adhering to the peripheral surface of the photoconductor drum 20 on the tip surface 1a, the sliding direction of the cleaning blade 1 onto the photoconductor drum 20 is The body drum 20 is held in the opposite direction of rotation.

In addition to the above structure, there is also provided a cleaning device to which blower means for sucking the foreign matter S scraped off by the cleaning blade 1 is added.
It is mainly installed in a large electrophotographic image forming apparatus.

[0005]

However, in the comparatively small electrophotographic image forming apparatus, the cleaning device is designed to remove the foreign matter S only by the cleaning blade 1 as shown in FIGS. 4 and 5. Will be installed. In such an electrophotographic image forming apparatus, a part of the foreign matter S accumulated at the sliding contact position of the cleaning blade 1 leaks from the left and right side portions of the cleaning blade 1 as indicated by arrows in the figure, and the cleaning blade 1 May be redeposited on the non-printing area A ₂ of the photosensitive drum 20 that does not come into sliding contact with the other surface. Abnormalities such as deterioration of image quality due to exposure and device failure due to scattering of the foreign matter S may occur.

In order to avoid such a situation, a cleaning device having a structure in which the cleaning blade 1 is also brought into sliding contact with the non-printing area A ₂ is conceivable, but another problem arises due to the following reasons. This configuration is difficult to adopt.

That is, an extremely small amount of residual toner which is not removed by the cleaning blade 1 in the print guarantee area A ₁ shown in FIGS. 4 and 5 appropriately reduces the frictional resistance between the tip surface 1a and the photosensitive drum 20. It plays a role as a lubricant to stabilize the sliding direction of the cleaning blade 1 on the photosensitive drum 20. However, when the cleaning blade 1 is also brought into sliding contact with the non-printing area A ₂ where a toner image is not originally formed, the frictional resistance in the non-printing area A ₂ becomes higher than the frictional resistance in the print guarantee area A ₁ . As a result, the front end surface 1a of the cleaning blade 1 is caught in the rotation direction of the photosensitive drum 20 at the sliding contact position with respect to the non-printing area A _2, and the sliding contact direction of the cleaning blade 1 with respect to the photosensitive drum 20 is reversed ( (Indicated by a chain double-dashed line in the figure).

The present invention has been made in view of the above-mentioned conventional circumstances, and has a simple structure, which prevents foreign matter from wrapping around from the left and right outer side portions of the cleaning blade and more completely adheres to the photosensitive drum. It is an object of the present invention to provide a cleaning device capable of removing foreign matter.

[0009]

To achieve the above object, the present invention employs the following means. That is, as shown in FIGS. 1 and 2, the cleaning blade 1 slidably contacted with the photosensitive drum 20 causes the photosensitive drum 20 to move.
In the cleaning device 10 for the photoconductor drum adapted to remove the foreign matter S adhering to the peripheral surface of the cleaning drum, the sealing material 3 for removing the foreign matter S adhering to the peripheral surface of at least both ends of the photoconductor drum 20 is used as the cleaning blade. 1 is a cleaning device for the photosensitive drums arranged in parallel with each other.

[0010]

According to the above construction, the foreign material S leaking from the left and right sides of the cleaning blade 1 and reattached to the non-printing area A ₂ of the photosensitive drum 20 is captured by the sealing material 3.

[0011]

1 is a front view of an embodiment according to the present invention,
FIG. 2 is also a vertical side view.

In this embodiment, as shown in FIG. 1, a cleaning blade 1 made of a flexible material is supported by a holder 2 so that a front end surface 1a thereof projects obliquely downward. The cleaning blade 1 is connected to the photosensitive drum 2
In a region (corresponding to the paper width P _w in the illustrated example) slightly larger than the print guarantee region A _{1 of} 0, the seal material 3 is elastically slidably contacted with the photosensitive drum 20, and the seal material 3 is provided on the left and right sides of the cleaning blade 1. It is slidably contacted at both outer positions, that is, in the non-printing area A ₂ of the photosensitive drum 20 and at a position closer to the rotational direction of the photosensitive drum 20 than the sliding contact position of the cleaning blade 1.

The seal member 3 is made of a material that does not damage the photosensitive drum 20, such as a flexible material such as urethane rubber or a raised material such as Bethlon (trade name).
As shown in FIG. 2, from the back surface of the holder 2 to the photosensitive drum 2
It is supported by the seal member holder 4 protruding toward 0 so as to urge it in the normal direction of the peripheral surface at the sliding contact position with respect to the photosensitive drum 20.

According to the above embodiment, the foreign matter S leaking from the left and right side portions of the cleaning blade 1 and reattached to the non-printing area A ₂ of the photosensitive drum 20 due to the operation of the electrophotographic image forming apparatus, It will be captured by the sealing material 3. As a result, there is no risk of foreign matter adhering to the peripheral surface of the photoconductor drum 20 that has passed through the cleaning device 10, and it is possible to prevent deterioration of image quality and abnormalities of the device due to uneven charging or exposure.

The present invention is not limited to the above-described embodiment, and the mounting position of the sealing material may be before the cleaning blade or right next to the cleaning blade. Not only two sealing materials may be attached to the portion, but one sealing material having a width substantially equal to the width of the photosensitive drum may be slidably contacted.

Further, the present invention can be applied to a cleaning device to which a blower means is added, and the material of the sealing material, the specific configuration of the sealing material holder, etc. are applicable to the electrophotographic image forming apparatus. It may be appropriately selected according to

[0017]

As described above, according to the present invention, since the sealing material provided in parallel with the cleaning blade is slidably contacted with both ends of the photosensitive drum, the sliding contact position of the cleaning blade is directed to both the left and right outer sides. The foreign material that leaks out and adheres to the left and right side portions of the photosensitive drum is removed by the sealing material.

As a result, there is no risk that the photosensitive drum which has passed through the cleaning device according to the present invention will be subjected to the subsequent processing with foreign matter adhering thereto. It has the effect of preventing abnormalities.

[Brief description of drawings]

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

FIG. 2 is a vertical sectional side view of an embodiment according to the present invention.

FIG. 3 is a conceptual diagram of an electrophotographic image forming apparatus to which the present invention is applied.

FIG. 4 is a front view of a conventional example.

FIG. 5 is a vertical sectional side view of a conventional example.

[Explanation of symbols]

 1 Cleaning Blade 3 Sealing Material 20 Photosensitive Drum S Foreign Material

Claims (1)

[Claims] 1. A photosensitive drum, wherein a cleaning blade (1) slidably contacting the photosensitive drum (20) removes foreign matter (S) adhering to the peripheral surface of the photosensitive drum (20). In the cleaning device, a sealing material (3) for removing foreign matter (S) adhering to the peripheral surface of at least both ends of the photosensitive drum (20) is arranged in parallel with the cleaning blade (1). Body drum cleaning device.