JPH10104999A - Electrophotographic photoreceptor drum - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electrophotographic photoreceptor drum having an effective vibration suppressing action and simplified in structure by charging a hard elastic vibration suppressing material making pressure contact with a cylinder in a wide area into the cylinder. SOLUTION: A small piece 1a of a thermally expansible resin material having a forming agent preliminarily kneaded thereto is sealed into a photoreceptor drum 2, and the resulting photoreceptor drum 2 is dipped in a photosensitive layer applying solution 3. It is then lifted up, and heated and dried by a dryer to form a photosensitive layer on the surface of the drum 2, and the small piece 1a of the resin material is formed and expanded by use of this heating, whereby an integrated block-like vibration suppressing material 1 whose surface makes pressure contact with the drum inner surface is provided. Thus, the chattering of a cleaning blade can be solved, and since the vibration suppressing material is filled in the drum in the process of applying the photosensitive layer, an effective vibration suppressing action can be provided without reducing the working property.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a photosensitive drum for electrophotography such as a copying machine, a printer, and a facsimile.

[0002]

2. Description of the Related Art In a photosensitive drum for electrophotography, a toner cleaning operation for scraping off toner remaining on the drum surface without being completely transferred onto a sheet through a cleaning blade is always performed. However, due to variations in the hardness, friction coefficient, contact angle, pressure force, and roundness and eccentricity of the photosensitive drum, the cleaning blade jumps without smooth sliding on the photosensitive drum surface. The occurrence of chattering often causes a problem such that the photosensitive drum resonates and emits an unpleasant sound, causing a so-called cleaning blade squeal. However, as a countermeasure against such a problem, a vibration suppressing material made of a small piece of lead or the like is attached to the inner peripheral surface of the photosensitive drum via an adhesive tape so as to absorb resonance (Japanese Unexamined Patent Publication No. Hei 3-459).
No. 81) is known.

Meanwhile, the vibration suppressing material which should absorb resonance has a wide range of elasticity as a condition for preventing the propagation of vibration, similarly to a vibration isolating material used in general equipment, and has a wide range of load and vibration. It is necessary to have sufficient strength and durability to support a vibration source without causing permanent set. For this reason, it is desirable that the vibration suppressing material provided inside or on the inner surface of the photosensitive drum is not a small piece or the like, but a hard elastic material that is pressed against the inner surface of the drum with as large a surface as possible. Also, the means for fixing the vibration suppressing material to the inner surface of the drum requires time and effort for mounting, and unlike bonding with an adhesive which may be peeled off after mounting, it is surely secured by the pressing force of the vibration suppressing material itself. It is preferred that the form be retained.

[0004]

SUMMARY OF THE INVENTION The present invention satisfies the above-mentioned requirements of the prior art, eliminates chattering of the cleaning blade, and has an effective vibration suppressing action without lowering workability. Another object of the present invention is to provide a simple photosensitive drum for electrophotography.

[0005]

That is, according to the present invention, in a photosensitive drum for electrophotography having a photoconductive layer on the outer peripheral surface of a cylindrical support, a hard elastic vibration pressed against a large surface inside the cylinder. An electrophotographic photosensitive drum characterized by being filled with a suppressing material is provided, that is, the present invention forms the vibration suppressing material with a hard elastic body which is pressed against a wide surface on the inner surface of the photosensitive drum, The attachment to the inner surface of the drum is simultaneously performed by this pressing force.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to the drawings, an embodiment of the present invention will be described. In the embodiment shown in FIG. 1, a vibration suppressing material 1 is formed as a one-piece rigid foam tightly packed inside a photosensitive drum 2. FIG. ing. 2A and 2B show an example of the formation order. That is, as shown in FIG. 2A, a small piece 1a of a heat-expandable resin material in which a foaming agent is previously kneaded is enclosed in the photosensitive drum 2 and then the photosensitive drum 2
Is immersed in a photosensitive layer coating solution 3 as shown in FIG.
Next, this is heated and dried by a lifting dryer to form a photosensitive layer on the surface of the photosensitive drum 2, and at the same time, by utilizing the heating at this time, the small piece 1 a of the resin material is foamed and expanded, and the surface is pressed against the inner surface of the drum. An integrated block-shaped vibration suppressing material 1 is obtained. In this case, the expansion elastic resin material 1a used was thermator R (trade name) manufactured by Nitto Denko Corporation.

[0007]

According to the first aspect of the present invention, since the vibration suppressing material is filled into the photosensitive drum in a pressed state, the chatter of the cleaning blade can be eliminated. In the electrophotographic photosensitive drum according to the second aspect, since the vibration suppressing material can be filled in the photosensitive drum during the photosensitive layer coating step, effective vibration can be achieved without lowering workability. An inhibitory action can be provided. As a result, the chattering noise of the cleaning blade was eliminated, and the contamination of the horizontal tier of the image due to poor cleaning was eliminated.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a photosensitive drum in which a thermally expandable resin material is densely filled to form a vibration suppressing material.

FIGS. 2A and 2B are explanatory diagrams showing the order of formation.

[Explanation of symbols]

 1. Vibration suppression material 2. Photoconductor drum

Claims (2)

[Claims] 1. An electrophotographic photosensitive drum having a photoconductive layer on the outer peripheral surface of a cylindrical support, characterized in that the inside of the cylinder is filled with a hard elastic vibration-suppressing material that is pressed against a wide surface. Photoconductor drum for electrophotography. 2. The electrophotographic photosensitive drum according to claim 1, wherein said vibration suppressing material is made of a heat-expandable material.