JPH02199464A - Image carrier driving device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a photoreceptor belt drive device for an electrophotographic apparatus.

BACKGROUND OF THE INVENTION An endless belt-shaped photoreceptor (photoreceptor belt) is often used as a photoreceptor in electrophotographic apparatuses such as electrophotographic copying machines, optical printers, and facsimile machines. For example, as shown in FIG. 4, the photoreceptor belt 1 includes a driving roller 2, a driven roller 3,
13 and one of the driven rollers (1 in the example shown)
3) is provided at one end of a tension arm 15 that is biased to rotate around one point (in this example, the axis of the driven roller 3) by a spring 14, and presses the photoreceptor belt 1 outward to a predetermined position. It provides tension. The drive roller 2 is made of chloroprene rubber or the like.

As is well known, the circumferential surface of the photoreceptor belt is provided with equipment for carrying out electrostatic photographic processes such as charging, exposure, development, transfer, separation, cleaning, and static elimination, and exposes the photoreceptor belt charged in a negative manner. The electrostatic latent image formed is developed into a toner image, and after being transferred to a transfer paper fed to a transfer section, the transfer paper is separated from the photoreceptor belt and fixed, completing the recording.

Now, in an electrophotographic device that uses a photoreceptor belt as a photoreceptor, if the photoreceptor belt is driven by the main motor that drives the transfer paper conveyance member, the torque of the machine may fluctuate while the transfer paper is being conveyed. As a result, the speed of the photoreceptor held becomes uneven, jitter appears on the formed image, and abnormal images are likely to occur. This phenomenon occurs particularly when thick paper is used as the transfer paper.

SUMMARY OF THE INVENTION In view of the above-mentioned problems of an electrophotographic apparatus using an endless heddle-like photoreceptor as a photoreceptor, the present invention solves the problems of the photoreceptor belt even when thick transfer paper is used. It is an object of the present invention to provide a photoconductor driving device that can obtain good images with little jitter without causing speed unevenness.

Means for Solving the Problems In order to solve the above-mentioned problems, the photoreceptor drive device of the present invention is provided with an inertial member that is rotatable integrally with the shaft of the drive roller of the photoreceptor roller 1-, and also has the following features: The invention is characterized in that an elastic transmission member is interposed between the drive roller and its drive side member.

Function As described above, since an inertial member is provided that can rotate integrally with the shaft of the drive roller of the photoreceptor heald, and an elastic transmission member is interposed between the drive roller and its drive side member,
Even if a speed change of 4 occurs in the drive side member, the speed change is not directly transmitted to the drive roller of the photoreceptor heald, and the drive roller of the photoreceptor belt maintains a constant speed due to the inertial force of the inertia member. It can rotate, so that the linear velocity of the photoreceptor remains constant.

Circle 11 Below, embodiments of the present invention will be described in detail based on the drawings.

In the apparatus of the embodiment described below, a photoconductor drive motor is provided as a drive source for the photoconductor bell 1, which is independent of a main motor that drives a transfer paper conveyance means, a fixing roller, and the like.

FIG. 3 is a diagram showing an example of a mechanical drive system of such an apparatus. Drives the foot roller gear ↑6 directly connected to the feed roller, the paper feed roller gear 17 directly connected to the paper feed roller, the registration roller gear 18 directly connected to the registration roller, the conveyor belt 19 from the transfer section to the fixing section, and the fixing roller. The fixing roller gear 20 and the like are all driven by a main motor (not shown) via a main motor gear train 1 and a gear train provided between each gear.

A photoreceptor drive motor 4 is provided as a drive source for driving the drive roller 2 of the photoreceptor belt 1, and the photoreceptor drive belt 8,
The drive roller 2 around which the photoconductor heald is wound is driven via the photoconductor drive pulley 7, and the development unit drive gear 21 and the development unit drive belt 22, which are provided coaxially and integrally with the photoconductor drive pulley 7, are driven. The developing unit 1 is driven to the developing unit 1 which is not operated. As the photoreceptor drive motor 4, a stepping motor is used.

Stepping motors have the advantage of being inexpensive, but they are accompanied by vibrations, so it is necessary to prevent these vibrations from being transmitted to the photoreceptor and causing speed unevenness.

FIG. 1 and FIG. 2 show an embodiment of a photoconductor drive device that prevents vibrations of a photoconductor drive motor from being transmitted to the photoconductor.

The photoreceptor drive motor 4 is attached to the side plate 10 of the main body of the apparatus by a machine screw 23.
The power is supplied and the power on/off is controlled via the harness 24. An elastic drive belt (for example, a timing belt) 8 is connected between a pulley 4a provided on the output shaft of the drive motor 4 and a photoreceptor drive pulley 7 provided coaxially with the drive roller 2 of the photoreceptor belt 1. It's being passed around. The drive pulley 7 is a boss portion of an inertial member (bouncing wheel) 5 that is integrally and coaxially fixed to one end of a drive coupling shaft 9 that is movable in the axial direction of the drive roller 2 and detachable. and is coupled via an elastic connecting member 6 so that rotational force can be transmitted.

In this embodiment, the joint between the shaft of the drive roller 2 and the drive coupling shaft 9 is comprised of two pins implanted at radially symmetrical positions at the end of the drive roller shaft, and a joint between the drive roller shaft 2 and the drive coupling shaft 9. A structure is used in which the end flange is configured to engage and disengage two pins installed in the axial direction at symmetrical positions away from the axis, and the photoreceptor heald 1, the driving roller 2, and the driven roller 3 are connected to each other.
When the photoreceptor unit 1~ consisting of etc. is removed in the axial direction,
It can be easily engaged and disengaged, and when rotating in one direction, the radial pin and the axial pin always maintain contact, so that the rotational movement of the drive coupling shaft is accurately transmitted to the drive roller.

In addition, as the elastic connecting member, in this embodiment, pins implanted in the boss portions of the driving pulley 7 and the inertial member 5 are inserted into holes provided in a thick rubber disk so that the two do not come into contact with each other. is used.

However, as the above-mentioned detachable joint and elastic connecting member, various known ones other than those having the above-mentioned configuration can be used.

In this embodiment, the inertial member 5 is made of brass and has a thickness of 8 mm.
, a disc with a diameter of 100 mm and a boss integrally formed is used, but it goes without saying that the dimensions and material should be selected so that the optimum moment of inertia can be obtained depending on the conditions.

Since this device is configured as described above, the vibration of the photoconductor drive motor 4 is absorbed by the elastic photoconductor drive heald 8 and the elastic connecting member 6, and the drive roller 2 is stabilized by the inertia of the inertia member 5. Can rotate.

In the above embodiments, the structure in which the photoconductor drive motor is provided separately from the main motor has been described, or even in the case of a system in which the photoconductor is driven by the main motor via a clutch, the photoconductor is rotated by the main motor. The present invention can be applied by replacing the pulley fixed to the output shaft of the photoconductor drive motor in the above embodiment with the drive pulley fixed to the output shaft of the photoconductor drive motor in the above embodiment, and the rotation speed of the motor can be changed by the torque fluctuation of the machine as the transfer paper is conveyed. It is possible to prevent unevenness from being transmitted to the photoreceptor belt, and to prevent jitter from occurring.

Effects As described above, according to the present invention, vibrations of the photoreceptor belt drive source and rotational irregularities that occur due to conveyance of transfer paper are prevented from being transmitted to the photoreceptor, and the photoreceptor can be rotated stably. It is possible to obtain good images without jitter.

[Brief explanation of the drawing]

FIG. 1 is a partially sectional plan view showing the configuration of a photoconductor driving device according to an embodiment of the present invention, FIG. 2 is an exploded perspective view thereof, and FIG.
The figure is a side view showing a mechanical drive system of an electrophotographic apparatus in which the photoreceptor drive device is used, and FIG. 4 is a side view showing the schematic structure of a photoreceptor belt and its support device. DESCRIPTION OF SYMBOLS 1... Photoreceptor belt, 2... Drive roller, 3... Drive roller, 4... Drive motor, 5... Inertia member, 6... Elastic connection member (elastic transmission member), 8 ...Elastic photoreceptor drive belt (elastic transmission member)

Claims (1)

[Claims] It has a photoreceptor belt that rotates around a drive roller and a driven roller, and an electrostatic latent image formed on the photoreceptor belt by exposure to light is developed and the formed toner image is transferred to transfer paper. In the photosensitive belt driving device of the electrophotographic apparatus, an inertial member is provided to be rotatable integrally with the shaft of the driving roller, and an elastic transmission member is interposed between the driving roller and the driving side member. A photoconductor driving device characterized by: