JP3625927B2 - Electrophotographic photoreceptor - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an electrophotographic photosensitive member, and more particularly, to a conduction means between a substrate of an electrophotographic photosensitive member having a photosensitive layer formed on the outer surface of a cylindrical conductive substrate and a rotating shaft (drum shaft).
[0002]
[Prior art]
In order to form an electrostatic charge image on the electrophotographic photosensitive member prior to development, the surface charge on the exposed portion is released well by uniformly charging the surface of the photosensitive layer and then performing imagewise exposure. It is necessary.
As means for this, (1) the photoconductor substrate and the rotating shaft penetrating through the center of the flange are connected through a metallic leaf spring (Japanese Patent Laid-Open No. 62-229273), and (2) the flange A metal plate having a plurality of legs protruding in a linear shape is fixed to the tip of a portion that is press-fitted to a base end (Japanese Patent Laid-Open No. 4-2370885).
According to the above (1), the conductive flange spring is used to elastically press the inner surface of the photosensitive drum and the outer surface of the drum shaft to hold the drum flange. It is easy to perform good cleaning with less swelling. Further, according to the above (2), the flange can be press-fitted and fitted to the end portion of the base of the photosensitive member, and can be firmly fixed without bonding with an adhesive.
[0003]
[Problems to be solved by the invention]
However, as described in (1) and (2) above, when the ground member is a metal plate, there is a problem that abnormal noise and wear of the sliding portion occur when sliding with the rotating shaft.
An object of the present invention is to provide an electrophotographic photosensitive member that eliminates these defects and can be used for a long period of time.
[0004]
[Means for Solving the Problems]
In order to achieve the object, the present inventor has repeatedly studied from various angles. As a result, the conductive brush is attached to the flange, and the conductive brush is attached to the photoreceptor substrate (the back surface of the cylindrical conductive substrate) and the rotating shaft. It has been found that if they are brought into contact with each other, conventional inconveniences are eliminated and good results are obtained. The present invention has been made based on this.
Therefore, according to the present invention,
(1) In an electrophotographic photosensitive member in which a resin flange is press-fitted inside a cylindrical conductive substrate having a photosensitive layer formed on the surface, and a metal rotating shaft is provided through the center of the flange, the flange is conductive. An electrophotographic photosensitive member, wherein a brush is mounted in contact with the back surface of the cylindrical conductive substrate and the rotating shaft;
Is provided.
[0005]
Moreover, according to the present invention,
(2) In (1), one end of the conductive brush is focused by a plate-like conductive substrate, and the plate-like conductive substrate is brought into contact with the back surface of the cylindrical conductive substrate. Electrophotographic photosensitive member,
(3) In the above (1), the conductive brush is sandwiched between the plate-like electrode plate and the flange, and all or part of the peripheral edge of the plate-like electrode plate is placed on the back surface of the cylindrical conductive substrate. An electrophotographic photoreceptor characterized by contact,
(4) The electrophotographic photosensitive member according to (1), wherein the conductive brush is converged by a thermosetting conductive tape,
(5) The electrophotographic photosensitive member according to (1), wherein the tip of the conductive brush in the direction of the rotation axis is cut into an arc shape in accordance with the shape of the rotation shaft,
Is provided.
[0006]
DETAILED DESCRIPTION OF THE INVENTION
In FIG. 1, a conductive brush 5 is attached to a resin-made (polycarbonate, etc.) flange 1 with an adhesive tape 6, one end of the adhesive tape is in contact with the rotating shaft 2, and the other end is photosensitive. The state in contact with the inner wall of the body base 4 is shown. The conductive brush 5 is obtained by bundling a large number of SUS, carbon and the like processed into a diameter of 5 to 15 μm, preferably 7 to 12 μm.
[0007]
However, as shown in FIG. 1, simply contacting the conductive brush 5 with the rotating shaft 2 and the photoreceptor substrate 4 may result in a weak contact force and an intended resistance value may not be obtained. Therefore, for example, if a conductive brush is sandwiched with a plate-like conductive base material and the base material is bitten into the inner wall of the photosensitive member base when the flange is press-fitted, it becomes satisfactory.
FIG. 2 shows a state in which a plate-like conductive base material 7 is bent and a conductive brush 5 is sandwiched between the plates and attached to the flange 1 so as to meet such requirements. At this time, the flange 1 is provided with a boss, and a hole previously formed in the conductive base material 7 is fitted into the flange 1 to be fitted therein. When this is press-fitted into the photoreceptor base 4, the end of the conductive substrate 7 is in contact with the inner wall of the photoreceptor base 4. An aluminum plate or the like is used for the conductive substrate 7.
[0008]
Further, by simply bringing the conductive brush 5 shown in FIG. 2 and the plate-like conductive base material 5 sandwiching the conductive brush into contact with the photoreceptor substrate, there is some degree of stability over time of conduction. It does not mean that anxiety remains. Therefore, in the present invention, it is advantageous to adopt the configuration as shown in FIG.
FIG. 3 shows a state in which the electrode plate 3 is attached from above the conductive brush 5 attached to the flange 1. The attachment at this time is preferably performed by providing a boss on the flange 1 and fitting the electrode plate 3 cut and raised 3 ′ thereon. When pressed into the photoreceptor base 4, the conductive brush 5 is sandwiched by the leaf spring force of the electrode plate 3, and the contact state is stable over time.
[0009]
In addition, as shown in FIG. 1, the contact force between brushes is weak only by sticking the conductive brush 5 to the flange 1 with the general sticking tape 6, and the dispersion | variation in resistance value is large. As a solution, it is preferable to focus the conductive brush 5 with the conductive thermosetting tape 8 to reduce the variation in resistance value.
FIG. 4 shows a state where the conductive brush 5 is attached to the flange 1 with the conductive thermosetting tape 8.
FIG. 5 shows an example in which the conductive base material 7 and the conductive thermosetting tape 9 are used together.
[0010]
FIG. 6 is a view showing a state in which the tips of the conductive brushes 5 are aligned according to the shape of the rotating shaft 2. This is because when the tip of the conductive brush 5 (rotating shaft portion side) is flat, the contact force with the rotating shaft 2 varies depending on the location, and particularly at the central portion, the brush tip escapes greatly and the contact force becomes unstable. This is to avoid that. In the present invention, as a solution, the tip of the conductive brush 5 is cut into an arc shape in accordance with the cross-sectional shape of the rotating shaft 2.
[0011]
FIG. 7 is a view showing a combination of members that gives the best results in the embodiment of the present invention. According to the combination of these members, the conduction between the rotating shaft 2 and the photoconductor substrate 4 is stable, and clearing of a resistance value of 100 KΩ · cm or less can be measured with a digital multimeter manufactured by FLUKE.
[0012]
【The invention's effect】
According to the first aspect of the present invention, since the conductive brush attached to the flange is slid, abnormal noise and wear of the sliding portion can be prevented.
According to the invention of claim 2, since the conductive brush is sandwiched between the plate-like conductive base materials such as aluminum, the conduction between the brushes is stabilized, and the plate-like conductive material is directly applied to the photosensitive member. Since they are in contact with the inside, stable conduction can be obtained.
According to the invention of claim 3, since the conductive brush is pressed by the electrode plate, stable conduction over time can be obtained.
According to the invention of claim 4, since the conductive brush is converged by the conductive thermosetting tape, the conduction between the filaments of the brush is stabilized, and hair loss is prevented.
According to invention of Claim 5, since the front-end | tip of a conductive brush is cut | disconnected in circular arc shape, conduction | electrical_connection of a contact part with a rotating shaft can be stabilized in the width direction.
[Brief description of the drawings]
1A is a view showing the positional relationship of main members of an electrophotographic photosensitive member of the present invention, and FIG. 1B is a front view of FIG.
2A is a view showing the positional relationship of the main members of another electrophotographic photosensitive member of the present invention, and FIG. 2B is a front view of FIG. 2A.
FIG. 3A is a view showing the positional relationship of main members of another electrophotographic photosensitive member of the present invention, and FIG. 3B is a front view of FIG.
FIG. 4 is a view showing a state in which a conductive brush is attached to a flange using a conductive thermosetting tape.
5A is a front view of a state in which one of the conductive brushes is focused using a conductive thermosetting tape and a conductive substrate, and FIG. 5B is a side view of FIG. 5A. .
FIG. 6 is an explanatory diagram showing a state in which the tip of the conductive brush is cut in accordance with the shape of the rotating shaft.
FIG. 7 is an exploded perspective view showing a combination of members considered to be the best in the photoreceptor of the present invention.
8A is a diagram showing the positional relationship of main members of an example of a conventional photoconductor, and FIG. 8B is a front view of FIG. 8A.
[Explanation of symbols]
1 Flange 2 Rotating shaft 3 Electrode plate (3 'cut and raised)
4 Photosensitive substrate 5 Conductive brush 6 Adhesive tape 7 Conductive substrate 8 Conductive thermosetting tape

Claims (4)

A resin flange is press-fitted inside a cylindrical conductive substrate having a photosensitive layer formed on the surface, a metal rotating shaft is provided through the center of the flange, and a conductive brush is attached to the flange of the cylindrical conductive substrate. In the electrophotographic photoreceptor mounted so as to be in contact with the back surface and the rotation shaft ,
One end of the conductive brush is focused by a plate-like conductive substrate, and the plate-like conductive substrate is brought into contact with the back surface of the cylindrical conductive substrate. body. The conductive brush is sandwiched between a plate-like electrode plate and a flange, and all or part of the peripheral edge of the plate-like electrode plate is brought into contact with the back surface of the cylindrical conductive substrate. Item 2. The electrophotographic photosensitive member according to Item 1. 2. The electrophotographic photosensitive member according to claim 1, wherein the conductive brush is converged by a thermosetting conductive tape . The tip of the rotation axis direction of the conductive brush in accordance with the shape of the rotary shaft, an electrophotographic photosensitive member according to claim 1, wherein it has been found trimmed into an arcuate shape.

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