JPH02287473A - Electrophotographic device - Google Patents

Abstract

PURPOSE:To decrease the running cost by providing a photosensitive body surface cleaning unit which is attachable/detachable to the developing unit supporting means and having with an almost identical outer shape as the developing unit. CONSTITUTION:The photosensitive body 1 surface cleaning unit 10 having an almost identical outer shape as the developing unit 4 and which is attachable/ detachable to the developing unit supporting means 6 is attached. Therefore, only a developing device is made attachable/detachable to/from the device main body, the exchange when toner in the developing device is consumed can be carried out by only exchanging the developing device, and the photosensitive body 1 can be cleaned by attaching the cleaning unit 10 from the outside. Thus, the running cost can be reduced, and an exchange unit can be miniaturized.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an electrophotographic apparatus such as a printer or a copying machine that forms an image using an electrophotographic method.

2. Description of the Related Art In recent years, the range of applications of electrophotographic devices such as printers and copying machines has been rapidly expanding due to their high speed and excellent image quality.

However, such image forming apparatuses using electrophotography tend to have complicated and large processing units, and miniaturization and improvement of operability are major challenges, and various proposals have been made for this purpose.

As such a conventional electrophotographic device, Japanese Patent Application Laid-Open No. 58-18
An example shown in Publication No. 1061 will be explained with reference to FIG.

FIG. 5 is a diagram showing the process section around the photoreceptor of an electrophotographic apparatus, where 51 is a photoreceptor that rotates while holding an electrostatic image;
2 is a developing device for developing the electrostatic image on the photoreceptor 51; 56 is a toner; and 53 is a cleaner for cleaning the toner remaining on the photoreceptor 51 of the transfer device to paper. 54 is a charger for uniformly charging the photoreceptor 51; 56 is a window for image exposure to form an electrostatic image on the photoreceptor 51; and 57 is a charger for uniformly charging the photoreceptor 51; It is an opening for transferring to paper,
Each of these parts is housed in a case 55 and formed into a unit. This unit is designed to improve operability by allowing it to be replaced by taking it in and out of the apparatus after copying a certain number of sheets.

Problems to be Solved by the Invention However, in the above configuration, many parts such as a developing device, a photoreceptor, and a cleaner are housed in the unit.
When the toner in the developing device is consumed, it must be disposed of all at the same time.

Therefore, running costs are high, and the size of the unit itself is large, making it difficult to handle and carry.

Furthermore, the lifespan of the photoreceptor and the lifespan of this unit, which is determined by the amount of toner in the developing device, do not necessarily match, and the entire unit may have to be discarded because the toner has run out even though the photoreceptor can still be used, resulting in waste. There may be some exchanges.

In view of this, the present invention reduces the number of parts in the replaceable unit by making only the developing unit removable from the main body of the apparatus, and by installing a cleaning unit in place of the developing unit to clean the photoreceptor. It is an object of the present invention to provide an electrophotographic device that has low running cost, can be downsized, and is easy to handle.

Means for Solving the Problems The present invention provides a photoreceptor that moves while holding an electrostatic image, a developing unit that is close to the photoreceptor and develops the electrostatic image, and a developer that detachably supports the developing unit. The electrophotographic apparatus is provided with a cleaning unit that has a unit support means, has an outer shape substantially the same as the development unit, is removably attached to the development unit support means, and cleans the surface of the photoreceptor.

Effects of the present invention With the above-described configuration, only the developing device can be attached and removed from the main body of the apparatus, and only the developing device can be replaced when the toner in the developing device is consumed, and a cleaning unit can be attached to the photoreceptor from the outside. By making it possible to clean the electrophotographic apparatus, the running cost can be reduced, the replacement unit can be miniaturized, and an electrophotographic apparatus with excellent handling properties is provided.

Embodiment FIG. 1 is a cross-sectional view of a part of a process section of an electrophotographic apparatus according to an embodiment of the present invention. Reference numeral 1 denotes a selenium-based photoreceptor, around which there is a charger 2 for uniformly charging the surface of the photoreceptor 1, and a charger 2 for image-wise exposing the charged surface of the photoreceptor 1 to form a latent image. A laser optical system 3, a developing device (developing unit) 4 for developing the formed latent image into a toner image, and a transfer charger 5 for transferring the developed toner image onto paper are arranged. The developing device 4 is a support (
The developing roller 7 is supported by a developing unit support means (6), and when installed in the apparatus, the developing roller 7 is positioned close to the photoreceptor 1 so as to be capable of developing. The support body 6 is movable between a position F indicated by a solid line in FIG. 1 and a position R indicated by a broken line.

The configuration of this embodiment is as described above, and its operation will be explained next. FIG. 1 shows the normal, ready-to-use state. During operation, the photoreceptor 1 rotates in the direction of arrow A, and the surface of the photoreceptor 1 is uniformly and positively charged by the charger 2. Next, the surface of the photoreceptor 1 is partially exposed by the laser optical system 3 according to the image signal to form a latent image. The formed latent image is developed by a developing device 4, and a toner image is formed on the photoreceptor 1. At this time, the toner is reversely developed with toner having the same polarity as the polarity with which the photoreceptor 1 is charged by the charger 2. That is, by applying a bias 8 between the photoreceptor 1 and the developing roller, toner is deposited only on the exposed portion to form a toner image.

Next, the formed toner image is transferred by the action of the transfer charger 5 onto paper 9 which is passed between the photoreceptor 1 and the transfer charging hot stone. After the toner is transferred onto the paper 9, a portion of the toner remaining on the surface of the photoreceptor 1 is charged together with the photoreceptor 2 by the charger 2, and then reaches the exposure position. At this time, since the amount of toner on the photoreceptor 1 is small, it does not affect the formation of the next latent image by the laser optical system 3. Furthermore, at the time of the next development, the potential of the developing roller 7 with respect to the photoreceptor 1 due to the bias 8 is set lower than the potential of the unexposed portion of the photoreceptor surface at the development position, so that the potential remaining on the photoreceptor 1 remains on the photoreceptor 1. Unnecessary toner out of the toner remaining after transfer is returned to the developing device 4 again.

When the toner in the developing device 4 is consumed as described above, the developing device eject button (not shown) on the main body of the device is pressed.
By operating , the support body 6 moves to the R position while supporting the developing device 4, and the developing device 4 can be taken out from the apparatus. In this way, the developing device is replaced with a new one and the device is cerated to a usable state again.

Under normal usage conditions, unnecessary toner on the photoconductor 1 is returned to the developing device 4 as described above, but as the device is used for a long time, toner, paper powder, and minute dust accumulate on the surface of the photoconductor 1. etc. will accumulate.

In order to use the photoreceptor 1 for a long period of time, it is necessary to clean and refresh the surface of the photoreceptor 1 at regular intervals. FIG. 2 shows the state when cleaning the surface of the photoreceptor. At appropriate intervals during the period of use of the apparatus, the cleaning unit 10 is set on the support 6 in place of the developing device 4 to bring it into the state shown in FIG. A fur roller 11 whose surface is flocked with fibers is rotatably installed at a position facing the photoreceptor 1 of the cleaning unit 10. In addition, the cleaning unit 1 is placed in contact with the surface of the fur roller 11.
A holder impregnated with cleaning liquid is installed inside the 0.

When the photoconductor 1 and the far roller 11 rotate in the directions of arrows A1 and B in the state shown in FIG. Clean it by rubbing it lightly.

Next, FIGS. 3 and 4 are views of the developing section shown in FIGS. 1 and 2, respectively, viewed from the right side. A protrusion 13 is provided on the side surface of the developing device 4. When the developing device 4 is set on the support 6 and is in the state shown in FIG. It is detected that the developing device 4 is attached. On the other hand, in FIG. 4, a protrusion 15 is provided on the side surface of the cleaning unit 10 at a position different from that of the developing device 4, and as in the case of the developing device 4, a switch 16 detects that the cleaning unit 10 is installed. . When the cleaning unit 10 is attached to the main body of the apparatus, the photoreceptor 1 and the cleaning unit 10 are controlled to be automatically driven for a certain period of time.

The above is an explanation of the configuration and operation of this embodiment. According to this embodiment, the photoreceptor 1 can be easily refreshed by simply replacing the developing device 4 and the cleaning unit 10, and the photoreceptor 1 can be easily refreshed by simply replacing the developing device 4 and the cleaning unit 10. Since cleaner is not required, developing unit 4
When the toner in the developing device runs out, you only need to replace the developing device 4.The photoconductor 1 can be used until its own lifespan regardless of the amount of toner remaining in the developing device 4, and the cleaning unit 10 The cleaning unit 1o can be used many times since the object to be cleaned is a small amount of dust accumulated on the photoreceptor 1. Therefore, the number of parts in the replacement unit is minimal, the running cost is low, and the replacement unit is small. This is an electrophotographic device that is easy to handle.

As described in detail, according to the present invention, only the developing unit is removable from the main body of the apparatus, and by installing a cleaning unit in place of the developing unit, the photoreceptor can be cleaned 2 times. It is possible to provide an electrophotographic apparatus that has a small number of unit parts, has low running costs, can be downsized, and is easy to handle.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a process section of an electrophotographic apparatus according to an embodiment of the present invention, FIG. 2 is a sectional view of the process section showing a cleaning unit installed in place of a developing device, and FIG. FIG. 4 is a view of the cleaning unit shown in FIG. 2 as seen from the right, and FIG. 5 is a view of a conventional example. DESCRIPTION OF SYMBOLS 1...Photoreceptor, 4...Developing unit, θ...Developing unit support, 10...Cleaning unit, 11. ,
, Farora, 12. ,,holding body, 16...switch. Name of agent: Patent attorney Shigetaka Awano (1 person) Figure 1 Figure 16 - Switch Figure 2 / -9F: Body 4' - Developing unit

Claims (4)

[Claims] (1) It has a photoreceptor that moves while holding an electrostatic image, a developing unit that is close to the photoreceptor and develops the electrostatic image, and a developing unit support means that detachably supports the developing unit, An electrophotographic apparatus further includes a cleaning unit that has approximately the same external shape as the developing unit, is removably attached to the developing unit support means, and cleans the surface of the photoreceptor. (2) The electrophotographic apparatus according to claim 1, wherein the cleaning unit includes a fur roller that is rotatable in contact with the photoreceptor while being attached to the developing unit support means. (3) Claim 1 or 2, wherein the cleaning unit includes a cleaning portion impregnated with a liquid on the surface that contacts the photoreceptor.
The electrophotographic device described. (4) The electrophotographic apparatus according to claim 1, wherein the cleaning unit has detection means that can be detected separately from the developing unit when mounted on the developing unit supporting means.