JPS60147756A - Charging device - Google Patents

Abstract

PURPOSE:To prevent the surface of a charger from damages by forming a conductive plate-like member and a voltage applying means to the member and contacting the conductive plate-like member to the surface of a body to be charged having an amorphous silicon surface layer to charge the surface. CONSTITUTION:A photosensitive body 1 having an amorphous silicon surface layer carries toner 2 electrostatically and rotates under the toner-carrying status. The conductive plate-like member 3 is contacted with the photosensitive body 1 and connected to a DC power supply 5(500-10<3>V) and an AC power supply 7(400-600V)(400-10<3>Hz) through an elastic metal or conductive member. The toner 2 adhered to the photosensitive body 1 can be cleaned up simultaneously with the charging and the toner can be recovered by combining a toner recovering device 10 with the device concerned. Thus, ozone is not generated and the surface of the photosensitive body is prevented from damages.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a charging device for charging a photoreceptor in, for example, an electrophotographic machine.

[Technical background of the invention and its problems]

In electrophotographic machines and the like, corona charging using a charger is generally used to charge the surface of a photoreceptor. However, when corona discharge occurs in the atmosphere, a problem arises in that oxygen is ionized and ozone is generated. Contact charging involves bringing an electrode into contact with the photoreceptor and applying a voltage to the electrode to charge it.

Frictional charging through contact with brushes and brushes has been developed.

However, the contact charging method, in which an electrode is brought into contact with a photoreceptor, has the disadvantage that contact marks tend to be left on the surface of the photoreceptor when conventional selenium photoreceptors are used, and even when a brush is used, it cannot be used for long periods of time. There was a problem in that the brush would become curly over time and this would affect the surface of the photoreceptor.

[Purpose of the invention]

The present invention has been made based on the above circumstances, and an object of the present invention is to provide a charging device that does not generate ozone and does not damage the surface of a photoreceptor.

[Summary of the invention]

In order to achieve the above object, the present invention comprises an electrically conductive plate-like member and a voltage applying means for applying a voltage to the electrically conductive plate-like member, and the present invention includes a conductive plate-like member and a voltage applying means for applying a voltage to the electrically conductive plate-like member, and applies the voltage to the surface of a charged body having an amorphous silicon surface layer. This charging device does not generate ozone and does not cause damage to lightning or the surface of the body by contacting a conductive plate-like member to charge the battery.

[Embodiments of the invention]

Hereinafter, the present invention will be explained with reference to an illustrated embodiment.

In FIG. 1, reference numeral 1 denotes a photoreceptor as a charged member used, for example, in an electronic copying machine, which has an amorphous silicon surface layer, and electrostatically supports a developer (hereinafter referred to as toner) 2. Rotate as it is. A conductive plate member (hereinafter referred to as a blade) 3 is in contact with the photoreceptor 1 at an angle of 5 to 20 degrees with respect to the tangential direction of the photoreceptor 1 with a contact pressure of about 2 g/crrL. These three blades are plate-shaped members made of elastic metal (e.g. eborin bronze plate) or conductive rubber (e.g. urethane rubber), and in the case of phosphor bronze plate, the thickness is several hundred μm to several mm.

In the case of urethane rubber, one with a rubber hardness of 60 to 80 degrees and a thickness of several mm is suitable. A voltage applying means 4 is connected to the blade 3 . That is, the positive terminal is connected to the negative terminal of a DC power supply 5 which is grounded via a resistor 6, and the other terminal of an AC power supply 7 whose terminal is grounded on the opposite side to the DC power supply 5 is connected via a capacitor 8 and a resistor 9. connected.

When charging, the DC power supply 5 generates a DC current of 500~to
oov voltage and AC 400-600 from AC power supply 7
V (effective value), 400 to 1000) (z) is applied. This voltage is applied to the blade 3, and the photoreceptor l is charged.

Here, the polarity of the DC power source 5 may be reversed depending on the charging characteristics of the photoreceptor 1.

In addition, the blade 3 can clean the toner 2 adhering to the trapped photoreceptor 1 at the same time as charging, and the scraped off toner can be collected by combining the toner collecting device 1o.

〔Effect of the invention〕

As explained above, according to the trap of the present invention, no ozone is generated and the surface of the photoreceptor is not damaged.

[Brief explanation of drawings]

FIG. 1 is a configuration diagram showing an embodiment of the present invention. DESCRIPTION OF SYMBOLS 1... Charged body (photoreceptor), 3... Conductive plate member (pu-do), '4... Voltage application means, 10... Developer recovery device [t (toner recovery) Equipment) 0 Agent Patent attorney Noriyuki Chika (and 1 other person) Figure 1 μ

Claims (2)

[Claims] (1) A conductive plate-like member and a voltage applying means for applying a voltage to the conductive plate-like member, and the conductive plate-like member is brought into contact with the surface of a charged object having an amorphous silicon surface layer. □ A charging device characterized by being electrically charged. (2) The conductive plate-like member has a developer recovery device that scrapes off the developer carried on the surface of the charged object and collects the developer scraped off by the conductive plate-like member. A charging device according to claim 1.