KR920007721B1 - Transcription deviding apparatus for electrography - Google Patents

Abstract

In the electro-photo process employing an exposure drum, a cleaner, a developing implement, etc, a thin-film electric pole (25) is formed on the base surface (24) of non-conductivity in the exposure drum (11). A part of a thin-film electrode is exposed, the rest is made of an exposure layer (26) and a transfer-electrode brush (22). A separated electrode brush is sliding with the exposed part of thin-film electrode (25). Transfer separator (21) is formed to correspond with the width of transfer-and separate-electrode brush.

Description

Transfer Separator in Electrophotographic Process

1 is a schematic diagram of a conventional electronic copying machine.

2 is a detailed view of the transfer separation apparatus according to the present invention.

3 is a schematic diagram of an electronic copy machine using FIG.

* Explanation of symbols for main parts of the drawings

11: photosensitive drum 12: charger

13: exposure part 14: developer

17: cleaner 18: static eliminator

19: fuser 20: paper feed roller

21: transfer separator 22: transfer electrode brush

23: separation electrode brush

The present invention relates to an apparatus for transferring and separating electrophotographic processes, and more particularly, to an apparatus for transferring and separating electrophotographic processes that can maximize the effective area of an image in a small copying machine.

1 is a schematic diagram of a conventional general electron copying machine.

The operation of FIG. 1 will be described below.

The electric charge is evenly applied to the surface of the photosensitive drum 1 by the corona discharge of the charger. When the charged part reaches the exposure part 3 by the movement of the photosensitive drum, any image information ( Or an original) so that the above-mentioned charged portion is formed with a latent image of any type on the photosensitive drum 1. At this time, the latent image formed is moved to the developing unit 4 by the movement of the photosensitive drum 1, and the toner is removed from the developing unit 4 by the coulomb force of the latent image formed on the developing unit 4 and the photosensitive drum 1. ) Moves to the photosensitive drum and the latent image turns into a visible image. Subsequently, the photosensitive drum is moved and transferred to the transfer machine 5, and the copy paper fed by the feed roller 10 passes between the transfer machine 5 and the photosensitive drum 1.

In this case, charges are accumulated on the bottom of the copy paper by the corona discharge generated by the transfer machine 5, and thus a coulomb force acts between the charges and the charges of the toner on the photosensitive drum to move the toner to the copy paper surface. Therefore, toner is transferred to the copy paper.

Thereafter, the transfer paper attached to the photosensitive drum 1 by the electrostatic force is separated by the separator 6, and the separated copy paper is moved to consist of a heating roller and a pressure roller. When passing through the fixing unit 9, the latent image of the original is fixed on the copy surface by heat and pressure, and the desired copy is made.

On the other hand, a full amount of toner and a latent image exist on the photosensitive drum 1 passing through the transfer machine 5, where the toner is removed by a cleaning blade 7, and the appreciation is transferred to the static eliminator 8. To be removed.

The separator 6 is installed to separate the copy paper attached to the photosensitive drum 1 after being transferred from the electronic copying machine. In this case, since there is no space in which a separate corotron is separately installed, a separate belt is used, and a large electronic copier is used by separately installing a separate corotron.

However, in the case of belt type separation which is mostly used in small models, part of the image, that is, belt width conduction is not copied, and in the case of medium size models or more, there is a problem of increasing the manufacturing cost by using separate corotron separately.

Accordingly, an object of the present invention is to provide a transfer separation apparatus of a transfer photo process that can reduce the cost by miniaturizing the device having a function of transferring and separating.

It is another object of the present invention to provide a transfer separation apparatus of an electrophotographic process that can maximize the effective area of an image in a small copying machine.

In order to achieve the above object, the present invention provides an electrophotographic process including a photosensitive drum, a charger, an exposure unit, a developing unit, a cleaner, a static eliminator, etc. A transfer separator formed to correspond to the width of the formed transfer and separation electrode brush, and applying a DC voltage to the corona wire forming the transfer separator, and applying a DC voltage opposite to the voltage applied to the corona wire to the transfer electrode brush. It is configured to apply an alternating voltage to the separation electrode brush.

Hereinafter, the present invention will be described with reference to the accompanying drawings.

2 is a sectional view showing the main portion of the transfer separation device according to the present invention. The thin film electrodes 25 are formed in a stripe shape in the longitudinal direction on the surface of the non-conductive base 24, and the photosensitive layer 26 formed on the remaining portions except for the ends of the thin film electrodes 25 is formed. This consists of a photosensitive drum (11). In addition, the exposed portions of the thin film electrodes 25 are formed to slide in contact with the transfer and separation electrode brushes 22 and 23, and correspond to the widths of the transfer and separation electrode brushes 22 and 23. Thus, the transfer separator 21 is formed on the lower portion of the photosensitive drum 11, the transfer separator 21 is formed. And it has a power source to supply the voltage for the transfer and separation functions.

3 is a schematic diagram of an electronic copying machine employing the second drawing.

The operation will be described with reference to FIG. 2 above.

The conductive layer of the photosensitive drum 11 is sprite-type thin film electrode to independently control each subsystem (SUB-SYSTEM), that is, improve efficiency of charging, exposure, development, transfer, static elimination, and the like. It is divided into (25) and used. First, in charging, a high pressure is applied to the corona wire constituting the charger 12 to generate a corona discharge so that electric charges are generated at a constant potential on the photosensitive drum 11.

The photosensitive drum 11 rotates to electrically flow the thin film electrode 25 between the unnecessary charger 12 and the exposed portion 13 to prevent natural discharge while the uniform charge reaches the exposed portion 13. Leave floating. When a portion of the uniformly charged photosensitive drum 11 reaches the exposure portion 13, a latent image is formed by arbitrary exposure information (computer output signal or original image information). While the latent image passes through the developing unit 14, it is formed of toner and becomes a visible image. The developed and visualized image passes through the transfer separator 21 by the rotation of the photosensitive drum 11. At this time, a corona discharge is applied to a corona wire constituting the transfer separator 21 by applying a DC voltage (+ or-) of several KV. In addition, a discharge voltage is increased by applying a direct current voltage (− or +) to the transfer electrode brush 22 to conduct a − or + current to the thin film pole 25. Therefore, the visible image on the photosensitive drum 11 is transferred onto the copy paper fed by the paper feed roller 20.

At this time, since the copy paper is in close contact with the photosensitive drum 11 by electrostatic force, the separation electrode brush 23 is applied with an alternating voltage to separate the copy paper attached to the photosensitive drum 11. That is, a direct current voltage of 4000-7000 V is applied to the corona wire constituting the transfer separator 21, and a direct current voltage of OV- -1,000 V (or + 1,000 V) is applied to the transfer electrode brush 22 to increase the transfer efficiency. Let's do it. In addition, when an alternating voltage of 1,000 V or less or a DC voltage of ± 500 V or less is applied to the separation electrode brush 23 by superimposing an alternating voltage, an alternating current component is applied to the thin film electrode 25 so that electrostatic force is eliminated. 11) the adhesion between the sheets is reduced, so that the copy paper is separated from the photosensitive drum 11. At this time, when a voltage of 1,000 V or more is applied to the separation electrode 25, the toner transfer becomes rather poor and the copy quality is lowered. The higher the frequency of alternating current, the easier it is to separate, but if it is several KHz or more, the copy quality tends to be deteriorated as the image is disturbed due to the shaking of the paper.

The subsequent operation is the same as a conventional general electronic copying machine.

As described above, the present invention showed that one corona line constituting the transfer separator is shown as an example, but it should be understood that two or more corona lines may be used to improve the transfer and separation efficiency.

Therefore, the present invention can remove the portion that is not copied by the separating belt in the small copier, thereby maximizing the effective area of the image, and also in the medium and large copiers, a separate charger and a high pressure of several KV or more by separate corotrons. It does not require a power source, which saves costs.

Claims (1)

In an electrophotographic process including a photosensitive drum, a charger, an exposure unit, a developer, a vacuum cleaner, a static eliminator, and the like, a thin thin film electrode pole having a stripe shape on the surface of the non-conductive base 24 forming the photosensitive drum 11 is formed. 25) and an end portion of the thin film electrode is exposed and the remaining portion forms a photosensitive layer 26 so that the transfer electrode brush 22 and the separation electrode brush 23 are exposed portions of the end portion of the thin film electrode 25. A transfer separator 21 formed to correspond to the width of the transfer and separation electrode brush, applying a DC voltage to the corona wire forming the transfer separator 21, and applying a DC voltage to the transfer electrode brush 22. And a DC voltage opposite to the voltage applied to the corona wire and configured to apply an AC voltage to the separation electrode brush.

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