JPH0816037A - Photoconductive drum apparatus - Google Patents

Abstract

PURPOSE:To provide a photoconductive drum apparatus which can rotate smoothly and whose productivity and durability are improved. CONSTITUTION:Regrading a cylindrical photoconductive drum apparatus which is provided with a cylindrical photoconductive drum main body 1 and a driving gear system 2 installed in the end part of the photoconductive drum main body 1 coaxially and which retains printing information as an electrostatic latent image state formed by receiving light beam L in the surface of the photoconductive drum main body 1; the driving gear system 2 is composed of a cylindrical core 3 made of plastic whose one end part is press-inserted into the end part of the photoconductive drum main body 1, a gear part 4 fixed coaxially in the other end part of the cylindrical core 3, and a rotary power transmission system 5 which is installed in the same axis of the gear part 4 to transmit the rotary driving force of the gear part 4 to the cylindrical core 3 from the inside.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a photoconductor drum device, and more particularly to a photoconductor drum device having a drive transmission member such as a drive gear mechanism at its end.

[0002]

2. Description of the Related Art A conventional photosensitive drum is externally driven via a drive transmission member such as a drive gear.
In this case, a part of the drive transmission member is press-fitted into the photosensitive drum main body or is bonded after insertion and assembly, thereby preventing the drive transmission member from idling with respect to the photosensitive drum main body and smoothly driving the photosensitive drum main body to the external drive described above. It is designed to let you.

[0003]

However, in the above-mentioned conventional example, it is difficult to press fit the drive transmission member to the photosensitive drum main body, especially high temperature press fitting for integration due to the difference in temperature expansion due to the difference in members. It was. In addition, the integration of the photosensitive drum body and the drive transmission member with an adhesive does not have an adhesive suitable for both, and it takes a considerable amount of time to dry, and at the same time it is troublesome to apply the adhesive uniformly. For this reason, there is a problem in durability due to deterioration of the adhesive due to aging and the like, resulting in poor workability and durability.

[0004]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a photoconductor drum device which is capable of improving the disadvantages of the conventional example, particularly capable of smoothly rotating and improving productivity and durability. And

[0005]

According to the present invention, a cylindrical photosensitive drum main body and a drive gear mechanism concentrically provided at the end of the photosensitive drum main body are provided, and the surface of the photosensitive drum main body is provided. In a cylindrical photosensitive drum device for holding print information formed by receiving a beam of light in the form of an electrostatic latent image, a drive gear mechanism is made of a plastic one end of which is press-fitted into an end of the photosensitive drum main body. A cylindrical core, and a gear portion coaxially fixed to the other end of the cylindrical core,
A configuration is employed in which the gear portion is concentrically provided and is configured by a rotational force transmission mechanism that transmits the rotational driving force of the gear portion to the cylindrical core from the inside. This aims to achieve the above-mentioned object.

[0006]

[Operation] When each wedge-shaped member 12 of the rotational force transmission mechanism 5 is urged by the gear portion 4 to move rotationally, the bending arm 11 is extended. Therefore, each wedge-shaped member 12 presses the inner wall of the cylindrical core 3 toward the outer periphery by the pressing force (repulsive force) of the bending arm 11. As a result, the cylindrical core 3 is expanded from the inner diameter side and pressed against the photosensitive drum body 1.

Subsequently, when each wedge-shaped member 12 continues to move in the same direction as the rotational force, the cylindrical core 3 rotates, and at the same time, the rotational force of the cylindrical core 3 is transmitted to the photosensitive drum body 1 via frictional force. As a result, the entire cylindrical core 3 and the photosensitive drum body 1 rotate in the rotational movement direction of each wedge-shaped member 12 (counterclockwise in FIG. 3).

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS.

1 to 4, reference numeral 1 denotes a cylindrical photosensitive drum body. A drive gear mechanism 2 is concentrically provided at both left and right ends of the photosensitive drum body 1 in FIG. The photosensitive drum body 1 has a function of holding the print information formed by receiving the laser beam light L on the surface thereof in the form of an electrostatic latent image.

The drive gear mechanism 2 has a cylindrical cylindrical core 3 made of plastic, one end of which is press-fitted into the end of the photosensitive drum body 1.
And a gear portion 4 concentrically fixed to the other end of the cylindrical core 3, and the cylindrical core 3 provided on the concentric portion of the gear portion 4 for rotationally driving the gear portion 4 described above. And a rotational force transmission mechanism 5 that transmits the internal force to the inside.

The rotational force transmitted to the gear portion 4 is transmitted to the cylindrical core 3 via the rotational force transmission mechanism 5 as described later, and the photosensitive drum body integrated with the cylindrical core 3 is formed. 1 is transmitted.

As shown in FIG. 3, the torque transmission mechanism 5 is
The rotary support shaft 10, four curved arms 11 radially extending from the rotary support shaft 10 toward the circumference, and the inner diameter of the cylindrical core 3 individually attached to the distal end of the curved arm 11 and described above. And a wedge-shaped member 12 that abuts on the side and engages in the rotational direction of the cylindrical core 3. These four curved arms 11 are provided at equal intervals.

Each of the four curved arms 11 has a curved convex portion protruding in the rotational direction (counterclockwise in FIG. 3).

Further, each wedge-shaped member 12 is provided on the side surface of the gear portion 4.
Four pressing pieces 4 for individually pressing each in the direction of rotation
A is provided. The pressing pieces 4A are provided so as to project from the above-described gear portion 4 toward the inner diameter side of the cylindrical core 3 at a predetermined length at equal intervals.

Next, the operation of the above embodiment will be described.

Now, when the above-mentioned wedge-shaped members 12 of the rotational force transmission mechanism 5 are biased by the gear portion 4 and rotationally moved in the counterclockwise direction in FIG. 3 together with the gear portion 4, the bending arm 11 is extended. Therefore, each wedge-shaped member 12 presses the inner wall of the cylindrical core 3 toward the outer circumference by the pressing force (repulsive force) of the bending arm 11. As a result, the cylindrical core 3 is expanded from the inner diameter side and pressed against the photosensitive drum body 1 described above.

Subsequently, when each wedge-shaped member 12 continues to move in the same direction as the rotational force, the cylindrical core 3 rotates, and at the same time, the rotational force of the cylindrical core 3 is transmitted to the photosensitive drum body 1 via frictional force. As a result, the entire cylindrical core 3 and the photosensitive drum body 1 rotate in the rotational movement direction of each wedge-shaped member 12 (counterclockwise in FIG. 3).

Here, in the above embodiment, the gear portion 4 has been described on the assumption that it is made of metal, but it may be made of plastic. Further, the gear portion 4 and the cylindrical core 3 may be integrally molded of plastic.

In the above embodiment, the case where the four bending arms 11 are used has been illustrated, but the number of the bending arms 11 may be three, or five or more.

Further, the wedge-shaped member 12 is exemplified as having different thicknesses along the moving direction, but it is also possible to use those having the same thickness as a whole.

FIG. 4 shows an example of the relationship between the photosensitive drum body 1 and other constituent members in an actual printing apparatus.

In FIG. 4, the electrostatic latent image on the photosensitive drum body 1 is developed by the developing means 21 and transferred onto the paper P by the transfer roller 22. The information transferred to the paper P is heated and fixed by the fixing rollers 23 and 24, and is sent out in the direction of arrow S.

[0023]

Since the present invention is constructed and functions as described above, according to the present invention, the drive gear mechanism 2 is not particularly required to use an adhesive agent and is not dependent on heat press fitting.
Can be mounted on the end portion of the photosensitive drum body 1 in a short time, and therefore workability and productivity therefor can be remarkably improved, and the rotational force transmitted to the gear portion can be acted by the rotational force transmission mechanism. Can be reliably transmitted to the photosensitive drum main body via the cylindrical core, and therefore, the photosensitive drum main body can be smoothly rotated as in the case of the conventional example. Since the drive gear mechanism 2 is attached to the end portion of the photosensitive drum body 1 without depending on the heating press-fitting, it is possible to completely eliminate the inconvenience such as the secular change of the connecting portion or the deterioration of the material due to heating, and thus In this respect, it is possible to provide an unprecedentedly excellent photosensitive drum device in which the durability can be remarkably improved.

[Brief description of drawings]

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

FIG. 2 is an explanatory diagram showing the relationship between the drive gear mechanism and the photosensitive drum body shown in FIG.

3 is a front view of the drive gear mechanism in FIG. 2 as viewed from the photosensitive drum body side.

FIG. 4 is an explanatory diagram showing the relationship with other components when the photosensitive drum main body disclosed in FIG. 1 is incorporated in a printing device.

[Explanation of symbols]

 1 Photosensitive Drum Main Body 2 Drive Gear Mechanism 3 Cylindrical Core 4 Gear Part 4A Pressing Piece 5 Rotational Force Transmission Mechanism 10 Rotation Support Shaft 11 Curved Arm 12 Wedge Member

Claims (3)

[Claims] 1. A cylindrical photosensitive drum main body, and a drive gear mechanism coaxially mounted on an end portion of the photosensitive drum main body, the surface of the photosensitive drum main body being formed by receiving beam light. In a cylindrical photosensitive drum device that holds print information in the form of an electrostatic latent image, the drive gear mechanism includes a plastic cylindrical core whose one end is press-fitted into an end of the photosensitive drum body. A gear part concentrically fixed to the other end of the cylindrical core, and a rotational force transmission mechanism mounted on the concentric part of the gear part and transmitting the rotational driving force of the gear part to the cylindrical core from the inside. A photoconductor drum device comprising: 2. The rotating force transmitting mechanism includes a rotating support shaft,
At least three bending arms radially extending from the rotation support shaft toward the circumference, and attached to the tip end of the bending arm to abut the inner diameter side of the cylindrical core in the rotation direction of the cylindrical core. 2. The photoconductor drum device according to claim 1, wherein the photoconductor drum device is configured by a wedge-shaped member that engages, and a pressing piece that presses each of the wedge-shaped members in a rotation direction thereof is provided on a side surface of the gear portion. . 3. The photosensitive drum device according to claim 1, wherein the curved arm is provided with a curved convex portion protruding in the rotational direction.