JPH04366865A - Electrical conductive brush type electrostatic charge device and electrophotographic recorder - Google Patents

Abstract

PURPOSE:To provide an electrical conductive type electrostatic charge device and an electrophotographic recorder which can simultaneously execute electrostatic charge and cleaning and which are fitted to be miniaturized as for the electrical conductive type electrostatic charge device used for electrostatically charging a recording body such as a photosensitive drum and the electrophotographic recorder using the electrical conductive brush type electrostatic charge device. CONSTITUTION:The electrical conductive brush type electrostatic charge device 20 is provided with an electrical conductive brush 21, a driving source which rotates the brush 21 at a fixed speed and a power source 21c which impresses a voltage on the shaft 21b of the brush 21. Besides, when a contact material 22 which abuts on the recording body 2 on the front side of the brush 21 is added, a cleaning effect is more improved. The electrophotographic recorder 30 is provided with the electrical conductive brush type electrostatic charge device 20 and a recovering means 31 for recovering toner cleaned by the device 20 to a developing device 6, besides.

Description

[Detailed description of the invention]

0001

[Field of Industrial Application] The present invention relates to a conductive brush charging device used for charging a recording medium such as a photosensitive drum used in an electrophotographic recording device such as an electrophotographic copying machine, an electrophotographic printer, or an electrostatic printer; The present invention relates to an electrophotographic recording device using the conductive brush charging device.

[0002] In this type of recording device, miniaturization, simplification,
With the demand for lower prices, there has been a need for a charging device that is small, has a simple configuration, and is capable of uniform and stable charging.

0003

2. Description of the Related Art Conventionally, recording apparatuses such as electrophotographic copying machines and electrophotographic printers employing a corona charger 1 shown in FIG. 4 have been widely used. The corona charger 1 is
It has a wire 3 parallel to the surface of a drum-shaped recording medium (photosensitive drum) 2 and a shield case 4 that covers the wire 3, and by applying a high voltage to the wire 3 and causing a corona discharge. , uniformly charges the recording medium 2 rotating in the clockwise direction indicated by the arrow.

A latent image is formed on the recording medium 2 uniformly charged by the corona charger 1 by exposure by the exposure means 5, and the latent image is developed by the developing device 6 to become a toner image. Thereafter, this toner image is transferred to a recording paper 10 by a transfer device 7.
0 and is fixed by the fixing device 8. The recording medium 2 is neutralized by a static eliminator 9, and the toner remaining on the recording medium 2 is cleaned by a cleaner 10 and collected in a waste toner container (not shown).

[0005]

[Problems to be Solved by the Invention] As mentioned above, in electrophotographic recording devices, printing is performed by repeating a series of processes of charging, exposure, development, transfer, cleaning, and fixing. The corona charger 1 is dangerous because it requires a high voltage of several kilovolts to generate corona discharge, and it also generates ozone, which poses a problem of polluting the atmosphere and equipment. Further, cleaners include a fur brush cleaner and a blade cleaner shown in FIG. 4, but these hinder the miniaturization and simplification of the device and have problems in processing the cleaned toner. Therefore, solutions to these problems are desired.

SUMMARY OF THE INVENTION An object of the present invention is to provide a conductive brush charging device that can perform charging and cleaning at the same time and is suitable for downsizing the device, and an electrophotographic recording device using the conductive brush charging device.

[0007]

[Means for Solving the Problems] FIG. 1 is a diagram explaining the principle of the present invention, in which 20 is a conductive brush charging device for cleaning and charging a recording medium 2, 30 is a recording medium 2, and a conductive brush charging device This is an electrophotographic recording device equipped with a device 20, a developing device 6, and the like. Note that the other constituent members of the electrophotographic recording device 30 are the same as those of the prior art, and the same symbols are used. The configurations of these devices are as follows.

The conductive brush charging device 20 has conductive brush fibers 21 attached to a shaft 21b parallel to the recording medium 2, protruding radially, and in contact over almost the entire length of the recording medium 2.
The conductive brush 21 has a conductive brush 21, a drive source (not shown) that rotates the conductive brush 21 at a constant speed, and a power source 21c that applies a voltage to the shaft 21b (first configuration).

[0009] Further, in the first configuration, a conductive brush 21 is added.
The conductive brush charging device may be configured by adding a contact material 22 that contacts the recording body 2 on the front side of the recording body 2 and weakens the adhesion force of residual toner on the recording body 2 to the recording body 2 (second composition).

The electrophotographic recording device 30 also includes a conductive brush charging device of the first or second configuration, and also includes a conductive brush charging device for collecting toner cleaned by the conductive brush charging device into the developing device 6. It is equipped with a recovery means (not shown).

[0011]

[Operation] The rotating conductive brush 21 cleans the surface of the recording medium 2 like a fur brush, and at the same time charges the surface of the recording medium 2. That is, the conductive brush charging device 20 performs both charging and cleaning. For this reason,
The cleaner that was previously required is no longer necessary. Especially the second
In the case of the configuration, the contact material 22 provided on the front side of the conductive brush 21 rubs the residual toner adhering to the recording medium 2 and weakens the adhesion force to the recording medium 2, so that the cleaning effect is reduced. Improve further.

Furthermore, in an electrophotographic recording device equipped with these conductive brush charging devices and collection means, the toner cleaned as described above is collected in the developing device, making it possible to downsize and simplify the device. .

[0013]

Embodiments Hereinafter, embodiments of the present invention will be described with reference to FIGS. 2 and 3.

FIG. 2 is a side view showing the outline of the electrophotographic recording apparatus of this example, and FIG. 3 is a front view showing the main parts of FIG.
31 is a collection means. Note that the same reference numerals are used for the same members as in FIG.

The brush fibers 21a of the conductive brush 21 are made of conductive rayon pile fabric, are attached to the shaft 21b, protrude radially, and are in contact with the recording medium 2 over almost the entire length thereof. The collecting means 31 includes a toner transport roller 33 provided at the lower part of a case 32 that covers the conductive brush 21 , and a toner transport path 35 that connects the case 32 and the case 34 of the developing device 6 .

The recording process up to static electricity removal by this electrophotographic recording apparatus 30 is the same as the conventional one, so a description thereof will be omitted. In this recording process, the toner that has not been transferred remains on the recording medium 2 and is neutralized, and the toner is transferred to the charging process. The toner remaining on the recording medium 2 is attached to the recording medium 2 by mechanical force, but it is rubbed by the contact material 22 provided on the front side of the conductive brush 21 and moves on the recording medium 2, causing the toner to be recorded. The adhesion to body 2 is weakened.

Thereafter, the surface of the recording medium 2 is charged by a conductive brush 21 rotating at a constant speed, and at the same time, the toner on the surface is charged by the conductive brush 21 like a fur brush cleaner.
cleaned by. Although this cleaning can be achieved without providing the contact material 22, it is more effective if the contact material 22 is provided as in this example. Thereafter, the brush fibers 21a come into contact with the adhered toner removing means 23 provided so as to be in contact with the brush fibers 21a, and the brush fibers 21a to which the toner has adhered slide against the adhered toner removing means 23, whereby the brush fibers 21a The toner adhering to the brush fibers 21a is separated from the brush fibers 21a.
a returns to a state where it can be charged.

The separated toner is transferred to a toner conveying roller 3.
3, the toner passes through the toner transport path 35 and is collected by the developing device 6.

[0019]

As described above, according to the present invention, it is possible to charge the recording medium with a conductive brush and to clean it at the same time, thereby eliminating the need for a cleaner. In this case, if a contact material is provided on the front side of the conductive brush to weaken the adhesion of toner to the recording medium, the cleaning effect will be further improved. Further, if the toner removed from the surface of the recording medium by the conductive brush is collected by the collecting means into the developing device, the apparatus can be made smaller and simpler because a cleaner is not required.

[Brief explanation of drawings]

FIG. 1 is a diagram explaining the principle of the present invention.

FIG. 2 is a side view schematically showing an electrophotographic recording apparatus according to an embodiment of the present invention.

FIG. 3 is a front view showing the main parts of FIG. 2;

FIG. 4 is a side view showing an outline of a conventional recording device using a corona charger.

[Explanation of symbols]

2 Recording body 6 Developing device 20 Conductive brush charging device 21 Conductive brush 21a Brush fiber 21b Axis 21c Power supply 22 Contact material 30 Electrophotographic recording device 31 Collection means

Claims (3)

[Claims] 1. In a conductive brush charging device for charging and cleaning the surface of a recording medium (2), a conductive brush is attached to an axis (21b) parallel to the recording medium (2) and protrudes radially; ) having conductive brush fibers (21a) in contact over almost the entire length of the conductive brush (21
), a drive source that rotates the conductive brush (21) at a constant speed, and a power source (2) that applies voltage to the shaft (21b).
1c) A conductive brush charging device characterized by comprising: 2. The structure according to claim 1, further comprising a conductive brush (
The recording body (2) is in contact with the recording body (2) on the front side of the recording body (21).
A conductive brush charging device characterized in that a contact material (22) is added to weaken the adhesion of residual toner on the recording medium (2). 3. The electroconductive brush charging device according to claim 1 or 2 is provided, and a collection means (31) is provided for collecting the toner cleaned by the conductive brush charging device into the developing device (6). An electrophotographic recording device characterized by: