JPH04345173A - Photosensitive body driving device - Google Patents

Abstract

PURPOSE:To provide a photosensitive body driving device capable of obtaining stable braking force over a long period by using a powder brake as a control loading means. CONSTITUTION:A photosensitive body 7 and a substrate 10 are integrally incorporated with a cleaning blade, and when they are used to the limit, they are integrally discarded. Then, the powder brake 9 using the flocculation of magnetic powder is fixed on the casing 10. Thus, the powder brake 9 of the long life is used, the stable braking force can be obtained over the long period, compared with when a braking agent such as a cork and a felt is used.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a photoreceptor drive device, and more particularly to an improvement in a braking load means for braking the rotational driving force of a photoreceptor in an electrophotographic apparatus.

0002

BACKGROUND OF THE INVENTION A conventional photoconductor driving device is reported in Japanese Utility Model Application Publication No. 179560/1983.
Here, the braking load means for the photosensitive drum includes one for the drum and one for the rotating driven shaft, and the braking means for the driven shaft is comprised of a powder brake.

[0003] Other conventional photoreceptor driving devices include one reported in Japanese Patent Laid-Open No. 63-27860, which describes a device that drives a developing roller from a photoreceptor using contact development. It is configured such that a braking force greater than the rotational force of the photoreceptor obtained by pressure contact with the roller can be applied to the photoreceptor.

0004

[Problems to be Solved by the Invention] However, in all of the conventional photoconductor drive devices described above, the photoconductor is configured to be frictionally braked from the outside, so the frictional force is stable in the initial stage, but over a long period of time. The problem was that it was unstable when crossing. Therefore, an object of the present invention is to provide a photoconductor driving device that can obtain a stable braking force over time.

[0005]

[Means for Solving the Problems] In order to achieve the above object, a photoconductor driving device according to the present invention rotatably supports a photoconductor on a base frame, and connects a rotational drive source to the photoconductor via a drive transmission means. In an electrophotographic apparatus, a rotational drive device for a photoreceptor in an electrophotographic apparatus is provided with a braking load means for braking the rotational driving force of the photoreceptor, in which the braking load means utilizes agglomeration of magnetic powder. It consists of a powder brake.

In the present invention, the braking load may be applied to a gear on the photoreceptor side of a gear pair that drives the photoreceptor. Further, the brake load means may be configured to be supported by a base frame that supports the gear train, or the brake load means may be configured to be supported by a base frame that mainly supports the photoreceptor. good. Furthermore, the braking load means may be elastically supported.

[0007]

[Operation] The invention as claimed in claim 1 uses a powder brake that utilizes the agglomeration of long-life magnetic powder (the electromagnetic part is replaced with a simple magnet and does not require electricity). It is possible to obtain more stable braking force over time than when felt or the like is used as the friction material.

According to the second aspect of the invention, the braking load can be applied more reliably by the meshing of the gears than in the case where the braking load is applied to the outer periphery of the photoreceptor using a friction material. Claim 3
In the described invention, the powder brake can be replaced at the same time before the end of its life and by replacing consumables such as the photoreceptor. In the invention according to claim 4, if the mechanical life is equal to that of the powder brake or the powder brake has a long life, the powder brake is located on the main body side and can be used until the end of its life, so it does not affect running costs. You can do it like this.

In the invention as set forth in claim 5, the braking load means may be configured to be elastically supported, and in this case, the photoreceptor gear and the powder brake gear can be meshed with each other without backlash. In the case of vibrations that cause the photoreceptor to move by the amount of backlash, the powder brake can reliably absorb the vibrations.

0010

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be explained below based on the drawings. 1 and 2 are schematic diagrams showing the basic configuration of a photoreceptor driving device according to an embodiment of the present invention. In FIGS. 1 and 2, reference numeral 4 denotes a photoconductor gear fixed to a photoconductor 7, and this photoconductor gear 4 is rotated by a drive gear 5. As shown in FIG. At the same time as the photoreceptor gear 4 is rotated by the drive gear 5, a braking load is applied by a powder brake gear 6 that utilizes agglomeration of magnetic powder meshing with the photoreceptor gear 4.

The rotation center shaft 4a of the photoreceptor 7 is supported by a bearing 8, and a powder brake 9 is engaged with one end of the rotation center shaft 4a. In this embodiment, the braking load is reduced by a powder brake 9 that utilizes the agglomeration of long-life magnetic powder to suppress rotational fluctuations of the photoreceptor due to fluctuations in the frictional force of the developing roller (not shown) and cleaning blade (not shown). It can be absorbed by applying it.

As described above, in this embodiment, since a long-life powder brake is used, a more stable braking force can be obtained over time than when cork, felt, or the like is used as the friction material. In addition, since the braking load is applied to the gear on the photoconductor side of the gear pair that drives the photoconductor,
Compared to applying a braking load to the outer circumference of the photoreceptor using a friction material,
Braking load can be applied reliably by the meshing of the gears.

Next, the mounting location of the powder brake will be explained using FIG. 3. As shown in FIG.
is rotatably supported via a rotation center shaft 4a by a base frame 10 that mainly supports it. The photoconductor 7 and the base frame 10 are attached with a cleaning blade (not shown).
etc., when the young ones reach the end of their lifespan, they are disposed of together with the main body. Furthermore, the powder brake 9 is fixed to the base frame 10.

As described above, in this embodiment, since the powder brake 9 is supported by the base frame 10 that supports the gear train, it is possible to replace consumables such as the photoreceptor before the powder brake reaches the end of its life. can be replaced at the same time. Next, in the present invention, as shown in FIG. 4, although the structure of the photoreceptor etc. is the same, the powder brake 9 is fixed to the base frame 11 on the main body side that supports the drive gear 5 that drives the photoreceptor gear 4. In this case, even if the base frame 10 including the photoreceptor 7 is discarded, the powder brake 9 is not discarded and can be used until the life of the machine. Therefore, running costs can be prevented from being affected.

Note that the examples shown in FIGS. 3 and 4 can be used depending on the machine life, and if the life of the powder brake 9 does not satisfy this, the example shown in FIG. 3 can be preferably used; If the target is set to be short and the life of the powder brake 9 satisfies this, the example shown in FIG. 4 can be preferably used. By the way, when a braking load is applied to the photoconductor 7 through a gear as in the examples shown in FIGS. 1, 3, and 4, backlash between the photoconductor gear 4 and the powder brake gear 6 may occur depending on the vibration level and frequency of the photoconductor 7. Depending on the size of the rotation, uneven rotation may occur. In this case, rotation unevenness can be prevented by meshing the photoreceptor gear 7 and powder brake gear 6 with no backlash, but rotation unevenness occurs due to poor meshing, so as shown in FIG. A powder brake 9 is fixed to a portion 11a extending from the base frame 11, and is pressed against the photoreceptor gear 4 by the springiness of the extended portion 11a. In addition, the load is
It is sufficient that the force is slightly stronger than the force that tends to spread both gears in the normal direction due to meshing rotation of both gears.

Since the powder brake 9 is configured to be elastically supported in this manner, the photoreceptor gear 4 and the powder brake gear 6 can be meshed with each other without backlash. Therefore, in the case of vibration that causes the photoreceptor to move by the amount of backlash, the powder brake 9 can reliably absorb the vibration.

[0017]

According to the present invention, a stable braking force can be obtained over time.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing the basic configuration of a photoreceptor driving device according to an embodiment of the present invention.

FIG. 2 is a schematic diagram showing the basic configuration of a photoreceptor driving device according to an embodiment of the present invention.

FIG. 3 is a diagram illustrating the mounting location of a powder brake according to an embodiment of the present invention.

FIG. 4 is a diagram illustrating a photoconductor driving device that can be applied to the present invention.

FIG. 5 is a diagram illustrating a photoconductor driving device that can be applied to the present invention.

[Explanation of symbols]

4 Photoconductor gear 4a Rotation center axis 5 Drive gear 6 Powder brake gear 7 Photoreceptor 8 Bearing 9 Powder brake 10 Base frame 11 Base frame 11a Extended part

Claims (5)

[Claims] Claim 1: A photoreceptor is rotatably supported on a base frame, a rotational drive source is interlocked and connected to the photoreceptor via a drive transmission means,
In a photoreceptor rotational drive device in an electrophotographic apparatus comprising a braking load means for braking the rotational driving force of the photoreceptor, the braking load means is a powder brake using agglomeration of magnetic powder. 1. A photoconductor driving device comprising: 2. The photoconductor driving device according to claim 1, wherein the braking load is applied to a gear on the photoconductor side of a gear pair for driving the photoconductor. 3. A rotational drive device for a photoreceptor in an electrophotographic apparatus in which a base frame that mainly supports the photoreceptor is separable from a base frame that supports a gear train, wherein the braking load means supports the gear train. 3. The photoreceptor driving device according to claim 1, wherein the photoreceptor driving device is supported by a base frame. 4. In an apparatus for rotating a photoreceptor in an electrophotographic apparatus in which a base frame that mainly supports the photoreceptor is separable from a base frame that supports a gear train, the braking load means mainly supports the photoreceptor. 3. The photoreceptor driving device according to claim 1, wherein the photoreceptor driving device is supported by a supporting base frame. 5. The photoreceptor driving device according to claim 1, wherein the braking load means is configured to be elastically supported.