JPH01154186A - Image forming device - Google Patents

Abstract

PURPOSE:To scale down a device and to facilitate its maintenance and management by employing a grounded conductive brush which comes into contact with the surface of the photosensitive layer of a photosensitive body as a destaticizer. CONSTITUTION:The conductive brush 12 possessing width corresponding to the full length of a photosensitive drum 1 possessing one grounded side is provided on the back of cleaning units 9 and 10 so that the tip of the brush comes into contact with the surface of the photosensitive drum 1. Charges remaining no the surface of the photosensitive drum after the completion of transfer are grounded 13 and destaticized through the conductive brush 12. Thus, an image forming device can be scaled down, and its cost can be reduced. In case of the conductive brush 12, deterioration in destaticizing effects due to the attachment of foreign matters such as floating toner is hardly found, whereby maintenance and management are considerably facilitated.

Description

[Detailed description of the invention] (Industrial application field) The present invention relates to a photosensitive drum, a charger, an exposure device, and a developer.

The present invention relates to the miniaturization and simplification of an image forming apparatus in which elements necessary for forming an image on copy paper, such as a transfer device and a static eliminator, are integrally formed.

(Prior art and its problems) As an electrophotographic image forming apparatus, as shown in FIG.
, the photosensitive drum (
1) An exposure device (3) that forms an electrostatic latent image on a surface, a developer (4) that makes the electrostatic latent image visible with toner, and a transport roll (5).
) transfer device (
7), a peeling device (8) that peels the transferred copy paper from the photosensitive drum surface and sends it to a fixing device (not shown); and a cleaning device (9) that removes toner from the photosensitive drum surface after transfer to clean it. GO), and those equipped with a static eliminator (II) that eliminates the surface potential of the photosensitive drum surface are known.

By the way, in such an image forming apparatus, a static eliminator (
10. Conventional static neutralization methods, i.e., those that irradiate the photosensitive drum surface with a light source such as LED, tungsten incandescent lamp, fluorescent lamp, EL, etc., to eliminate static electricity, or electric field static neutralization methods, that is, AC voltage or surface potential with opposite polarity. A method is used in which static electricity is removed by applying a DC voltage. However, these methods require smaller size and simpler structure of the image forming apparatus than currently available.

It is difficult to meet strong demands such as ease of maintenance management.

In other words, when using the optical static elimination method, in addition to using a light source that is difficult to miniaturize, measures are taken to prevent a drop in charging voltage due to light leakage, measures are taken to prevent heat generation when the light source is an incandescent lamp, and measures are taken to prevent the photoreceptor from becoming more compact. Measures against light fatigue are necessary. Therefore, the static eliminator is made larger and more complicated, which makes the image forming apparatus larger and more complicated, thereby increasing its cost. In addition, as the device is used, toner and other foreign matter floating inside the device adhere to the surface of the light source, gradually reducing the amount of light and reducing the static elimination effect.

Therefore, since it is necessary to inspect and clean it, there is a drawback that maintenance management is troublesome and running costs are high.

In addition, electric field static elimination not only requires a high voltage that requires a booster and insulation measures, but also requires measures to prevent corrosion due to ozone, measures against fatigue due to the electric field of the photoreceptor, and measures to detect disconnection of the discharge wire. This also makes the static eliminator larger and more complicated, making the image forming apparatus more expensive. In addition, the adhesion of l-ner and other foreign matter floating in the device to the discharge wire reduces the static elimination effect, so inspection and cleaning are required, and maintenance management is the same as with the optical static elimination method. This is troublesome and increases running costs. Therefore, unless some new countermeasure is devised, it is difficult to expect image forming apparatuses to be made smaller and cheaper than they currently are.

(Object of the Invention) The present invention has been made for the purpose of providing an image forming apparatus that can meet the above-mentioned demands such as miniaturization, and will next be described in detail with reference to the drawings.

(Means of the present invention for solving the problems) The present invention is characterized by the above-mentioned conventional photostatic charge removal.

Instead of a static eliminator based on the electric field static eliminator method, a conductive brush with a width corresponding to the entire length of the photosensitive drum with one end grounded is placed behind the cleaning device (9) θ0) as shown in the partial diagram in Figure 2. (121 is provided so that its tip is in contact with the surface of the photosensitive drum (1), and the electric charge remaining on the surface of the photosensitive drum (121) after the transfer is completed is grounded via the conductive brush (03) to eliminate the electric charge. That's what I did.

In this way, static elimination can be performed only with a conductive brush that has a simple structure and does not require a large installation space, and can be removed using a light source or high voltage generator such as conventional optical static elimination or electric field static elimination, and even light leakage. There is no need for countermeasures, photoreceptor fatigue countermeasure devices, or other attached devices that make the static eliminator large and complicated.

Therefore, the static eliminator is significantly smaller and simpler than the conventional one, and as a result, the image forming apparatus can be made smaller and simpler, and manufacturing costs can be reduced. In addition, in the case of a conductive brush, there is almost no deterioration in the static elimination effect due to the adhesion of foreign matter such as floating toner, so maintenance management is extremely easy, and the running cost of the image forming apparatus can be reduced accordingly. Next, an experimental example of the present invention will be explained.

The conductive brush 02) is made of rayon fibers with a thickness of 6 denier and carbon dispersed in them, and the density is 80,000 fibers/inch, and the resistance value is 106 to 108 Ω・cm. b), and then attach the metal support (
12a) Conductive adhesive (1
2b) was used. This is then charged to -700V and rotated at 15 times/min.
Developed in contact with the 0mm organic photosensitive drum surface.

Static electricity was removed after exposure, transfer, and cleaning. As a result, a static elimination potential of -400V was obtained, and it was confirmed that the static elimination effect was comparable to that of the conventional one. It was also confirmed that sufficient charge removal was achieved when an amorphous photosensitive drum was used.

Note that in order to enhance the static elimination effect, an AC or DC bias voltage may be applied to the conductive brush as necessary. In addition, static elimination becomes unstable if there is a change in humidity, but in this case, it can be stabilized by first reacting the rayon with an organic solvent such as benzyl chloride and then using a brush that has carbon dispersed in it to give it conductivity. can.

(Effects of the Invention) As is clear from the above, according to the present invention, it is possible to simplify the size and maintenance of an image forming apparatus that integrates a photoreceptor, a charger, an exposure device, and other elements necessary for image formation. It can be planned.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of an image forming unit, FIG. 2 is an explanatory diagram of the present invention, and FIG. 3 is a side view of a conductive brush. (1)...Photosensitive drum, (2)...Charger, (
3)... Exposure device, (4)... Developer device, (5)...
・Conveyance roller, (6)...Copy paper, (7)...Transfer device, (8)...Peeler, (9)00)...Cleaning device, (10...Static eliminator, q. Conductive brush, (12a) Support, (12b)
...Conductive adhesive, surface...ground. Patent applicant: 1 person other than Shindengen Kogyo Co., Ltd.

Claims (2)

[Claims] (1) In an image forming apparatus equipped with a photoreceptor, a charger, an exposure device, a transfer device, a peeler, a cleaning device, a static eliminator, etc., a grounded conductive material that contacts the photosensitive layer surface of the photoreceptor serves as the static eliminator. An image forming device characterized by using a brush. (2) In claim 1, the conductive brush of the static eliminator is formed from carbon-containing fibers based on rayon, and the base fibers are treated with a moisture-proofing reaction using an organic solvent. Image forming device.