JPH06230645A - Multiple image forming device - Google Patents

Abstract

PURPOSE:To eliminate static electricity of both a photosensitive body and a transfer material by one corona discharger, and to reduce the cost, to save the space and further to restrain the production of ozone in this device as compared with the conventional constitution where corona dischargers are respectively used for both the photosensitive body and the transfer material. CONSTITUTION:In the multiple image forming device where a color image is formed by forming the toner images of respective colors on the photosensitive body 1 and superposing and transferring them on the transfer material; the corona discharger 6 for static electricity elimination where discharge from a wire is radiated to both the photosensitive body 1 and the transfer material by opening a shield which shields the wire to the photosensitive body 1 and the transfer material sides is installed at a position just after transfer.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multiple image forming apparatus in a color copying machine or the like for sequentially superposing and transferring toner images on a photoconductor onto a transfer material.

[0002]

2. Description of the Related Art Conventionally, in a transfer apparatus that performs multiple transfer, in order to maintain good transfer when performing multiple transfer, in order to eliminate control of transfer efficiency such as sequentially increasing applied transfer voltage. In Japanese Patent Publication Sho 61-3762
As described in Japanese Patent No. 8, the transfer material is discharged by a corona discharger facing the transfer material after the transfer. On the other hand, a corona discharger has been conventionally used to remove the potential remaining on the surface of the photoconductor after the transfer and before the cleaning even for the photoconductor after the transfer.

[0003]

However, in the apparatus having such a conventional structure, a corona discharger for discharging the transfer material after the transfer and a corona discharger for discharging the photosensitive member are provided respectively, and a space is taken, In addition, there is a problem that the amount of ozone generated also increases.

The present invention has been made in view of the above, and a corona discharger for discharging a transfer material after transfer and a corona discharger for discharging a photoconductor are integrally provided, and a corona discharger is used to perform exposure. By removing electricity from both the body and transfer material, it is cheaper and more compact than before,
It is another object of the present invention to provide a multiplex image forming apparatus capable of reducing the amount of ozone generated.

[0005]

To achieve the above object, a multiple image forming apparatus according to the present invention forms a toner image of each color on a photoconductor 1 and superimposes the toner image on a transfer material. In a multiplex image forming apparatus that forms a color image by using a shield 1 that shields the wire 11 at a position immediately after transfer.
A corona discharger 6 for static elimination is provided in which 2 is opened to the side of the photoconductor 1 and the transfer material so that the discharge from the wire is radiated to both the photoconductor 1 and the transfer material.

[0006]

[Operation] Both the charges of the photoconductor 1 and the transfer material are simultaneously discharged by one corona discharger 6 for discharging.

[0007]

EXAMPLES Examples of the present invention will be described with reference to the drawings. FIG. 1 shows a specific embodiment of the present invention. A charger 2, a developing device 3, a charge eliminator 4, a transfer drum 5, a corona discharger 6 are arranged around a photoconductor 1 in the rotation direction thereof. The cleaning brush 7 and the cleaning blade 8 are sequentially arranged to face each other. The photoconductor 1 is provided inside the transfer drum 5.
A transfer device 9 is provided toward the side. A space between the charger 2 and the developing device 3 is exposed by laser light.

The corona discharger 6 discharges an electric charge having a polarity opposite to that of the transfer device 9. This corona discharger 6 is shown in FIG.
As shown in (a) and (b), both ends of the holding member 10, 1
One wire 11 held at 0 and the shield 1 opened on both sides, that is, both the photoconductor 1 side and the transfer drum 5 side.
It consists of 2. The width of the shield 12 on the transfer position side is short. The tensioned position of the wire 11 is set such that the one where a large amount of current is required is closer to the photosensitive member 1 and the transfer material. Further, the developing device 3 is configured as a rotating body, and supports black, yellow, magenta, and cyan phenomenon devices in a circumferentially divided manner. The electrostatic latent images on the photoconductor 1 are indexed to the developing positions, and the latent images on the photoconductor 1 corresponding to the respective colors are visualized with toner.

In the above structure, the transfer material supplied between the photoconductor 1 and the transfer drum 5 moves in accordance with the rotation of both, and during this time, the toner image on the photoconductor 1 is transferred onto the transfer material by the transfer device 9. To be done. Then, the toner image on the transfer material is applied with an electrostatic charge having a polarity opposite to that of the transfer device 9 by the corona discharger 6. At this time, the electrostatic charge having the opposite polarity to that of the transfer device is also applied to the photoconductor 1 by the corona discharger 6. By the discharge of the corona discharger 6, both the toner on the photoconductor 1 and the toner on the transfer material are discharged.

As the high voltage applied to the corona discharger 6, an AC voltage, a DC voltage having a polarity opposite to that of the transferred corona discharge charge, or an AC voltage in which a DC bias voltage for controlling the amount of static elimination is weighted is used. For example, the AC voltage is 3.6 KV and the weighting bias voltage is -0.6 KV.

FIG. 2 shows another embodiment of the present invention. For this, a plurality of photoconductors 1 for each color are arranged in a straight line, a transfer belt 13 is installed so as to be in contact with the line, and a corona discharger 6 facing both the photoconductor 1 and the transfer belt 13 is provided downstream of each transfer position. To place. Each corona discharger 6 includes a photoconductor 1, a charger 2, a cleaning brush 7,
One unit is configured together with the cleaning blade 8, and each color unit can be replaced. In this embodiment, the color toner images of the respective color units are sequentially transferred onto the transfer material sent by the transfer belt 13.

[0012]

According to the present invention, one corona discharger 9
Can remove static electricity from both the photoconductor 1 and the transfer material.
Compared with the conventional configuration in which a corona discharger is used for both the photoconductor 1 and the transfer material, cost reduction and space saving, and further ozone generation can be suppressed.

[Brief description of drawings]

FIG. 1 is a schematic configuration explanatory view showing an embodiment of the present invention.

FIG. 2 is a schematic configuration explanatory view showing another embodiment of the present invention.

FIG. 3 schematically shows the configuration of a corona discharger,
(A) is a plan view and (b) is a sectional view.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Photosensitive member, 2 ... Charging device, 3 ... Developing device, 4 ... Static eliminator,
5 ... Transfer drum, 6 ... Corona discharger, 7 ... Cleaning brush, 8 ... Cleaning blade, 9 ... Transfer device, 1
0 ... Holding member, 11 ... Wire, 12 ... Shield, 13 ...
Transfer belt.

Claims (1)

[Claims] 1. In a multiplex image forming apparatus for forming a color image by forming toner images of respective colors on a photoconductor 1 and superimposing and transferring the toner images on a transfer material, the wire 1 is placed at a position immediately after the transfer.
A corona discharger 6 for static elimination is provided in which a shield 12 for shielding 1 is opened to the photoconductor 1 and the transfer material side so that the discharge from the wire is radiated to both the photoconductor 1 and the transfer material. Characteristic multiple image forming apparatus.