JPS60205550A - Electrifying device - Google Patents

Abstract

PURPOSE:To enable stable electrification without leakage of an impressed voltage to a substrate by prohibiting the spread of a contactor owing to bending by an insulating layer and preventing said contactor from contacting with the substrate of an object to be electrified. CONSTITUTION:Silicone rubber to be used as an insulating material is coated on the end of an electrifying roller to form an insulating layer 7. One end 7a of the layer 7 is made flush with the one end face 6a (ther boundary between a photosensitive layer 6 and a substrate 5) of the layer 6. Spread of the contactor 3 owing to bending is prohibited by the layer 7, by which the contact of the contactor 3 with the substrate 5 is prevented and therefore stable electrification is made possible. Since the contactor 3 is embedded to a core material 2 by a V weave or W weave, the dislodging of the contactor 3 can be prevented by coating the silicone rubber on the end part. The spread of the contactor 3 owing to bending is prohibited by the layer 7 and the contact of the contactor 3 with the substrate 5 part of an object 4 to be electrified is prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an apparatus for charging a charged body such as a photoreceptor of an electrophotographic copying machine.

Prior Art A corona charger is known as a charging device for electrophotographic copying machines, but the corona charger uses high voltage, which is dangerous, and also generates ozone, which can damage other equipment.
<- Has the disadvantage of being slow.

Therefore, a contact charging type charging device has been developed in which a brush in which a large number of conductive fibers are implanted is brought into contact with an object to be charged, and a voltage is applied to charge the object.

However, with this charging device, when the brush comes into contact with the object to be charged, the fibers bend and spread, contacting the substrate of the object and causing the charge to leak to the substrate. It has the disadvantage that it cannot be charged.

That is, the object to be charged is a substrate provided with a photosensitive layer, and when the fibers are bent and spread, they protrude from the end surface of the photosensitive layer and come into contact with the substrate.

In order to prevent this, the fibers may be made to have high rigidity so that they are bent so that they do not spread out, but this has the disadvantage of damaging the surface of the charged object and causing fc damage.

Furthermore, since the fibers are implanted in the core material in a V-weave or W-weave manner, they fall off from the ends, causing various problems.

Purpose of the Invention When a charger having a large number of contacts made of flexible electrical resistors is brought into contact with an object to be charged, the contacts will not bend and spread out and come into contact with the substrate portion of the object to be charged. , the purpose is to prevent the contact from falling off.

Constituent of the Invention In a charger in which a core material is provided with a large number of contacts made of flexible electrical resistors, one end portion is coated with an insulating material to form an insulating layer,
The insulating layer prevents the contact from bending and spreading, and also prevents the contact from falling off.

Embodiment FIG. 1 is an overall perspective view, in which a charger 1 has a cylindrical core material 2.
The charging roller has a large number of contacts 3 made of flexible electrical resistors implanted on the surface of the charging roller, and is driven to rotate by contacting the surface of the charged object 4, and a voltage is applied thereto.

The charged body 4 has a cylindrical shape, with a photosensitive layer 6 provided on a substrate 5, and is driven to rotate.

Because of this, when the strip holder 1 is brought into contact with the charged object 4, the contact 3 bends and spreads, protrudes from the end 6α of the photosensitive layer 6 and contacts the substrate 5, and the applied voltage is It leaks to the substrate 5 and cannot be charged.

Therefore, in the present invention, the end of the charging roller is coated with an insulating material and silicone rubber to form an insulating layer 7, and one end 7α of this insulating layer 7 is connected to one end surface 6cL of the photosensitive layer 6 (the photosensitive N6 and the substrate 5).

Because of this, the insulating layer 7 can prevent the contactor 3 from spreading due to bending, and the contactor 3 can be prevented from coming into contact with the substrate 5, so that stable charging can be performed.

Further, since the contacts 3 are implanted in the core material 2 by V-weave or W-weave, they normally fall off from the ends, but since the ends are coated with silicone rubber, the contacts 3 can be prevented from falling off.

Note that the coating thickness is determined by the usage conditions of the charging roller, especially the distance from the charged object.

Although a charging roller was used in the above embodiment, a large number of contacts were installed on a 1,000-inch plate-shaped core material so that the tips of the contacts had the same shape as the surface shape of the object to be charged. The ends may be coated with silicone rubber to form an insulating layer.

Effects of the Invention Since the insulating layer 7 prevents the contact 3 from spreading out and preventing the contact 3 from contacting the charged body 40 and the substrate 5 portion, the applied voltage leaks to the substrate 5 portion. It can be charged stably without any problems.

This can be prevented by the insulating layer 7 coated on the drop tube of the contactor 3.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention, with FIG. 1 being an overall perspective view and FIG. 2 being a sectional view of an insulating layer portion. 1 is a band charging device, 2 is a core material, 3 is a contact, 4 is a charged object,
5 is a substrate, and 7 is an insulating layer. Figure 1

Claims (1)

[Claims] A charger 1 having a core material 2 with a large number of contacts 3 made of flexible electrical resistors is disposed so that the contacts 3 are in contact with the surface of a charged object 40, and a voltage is applied to charge the charged object. body 4
1. A charging device for charging a zero surface, characterized in that an end portion of the charger 1 is coated with an insulating material to form an absolute g layer 7.