Compact corona charging device

摘要

A corona discharge device including a corona discharge electrode in contact or closely spaced from a conductive shield electrode, the discharge electrode comprising a conductive wire coated with a relatively thick dielectric material so as to prevent the flow of conduction current therethrough. When the electrode is spaced from the shield, it is supported along its length on a dielectric surface and when it is in contact with the shield, the shield itself may provide the lengthwise support for the wire, or the support may alternatively be provided by a dielectric substrate on which the shield is carried. The delivery of charge to the photoconductive surface is accomplished by means of electric field separation of charges produced by the discharge electrode. These charges are produced by an alternating voltage applied to the discharge electrode. The flow of charge to the surface to be charged is regulated by means of a d.c. voltage bias applied to the shield electrode.