Solid state corona discharger

Abstract

A solid state corona discharger in corona chargers which charge and discharge photosensitive members in electrophotographic copying machines, ozone generators and the like. The solid state corona discharger has paired strip-shape ac electrodes which are arranged side by side nearly in parallel and spaced away from each other not to initiate discharge, a dielectric member layer which covers at least one side of the external surfaces enveloping both electrodes, and a thin dc-applied electrode which is in contact with one side of external surface of said dielectric layer and makes up a closed circuit loop of capacitances together with said ac electrodes (not connected in terms of direct current), as well as characterized by producing corona discharge between said ac electrodes and a dc-applied electrode with an ac power supply applied across said ac electrodes. In using the solid state corona discharger according to said configuration as a charger for a thin substance to be charged, the substance is charged by placing a dc-applied electrode opposite to the surface of the substance; connecting a dc power source between the dc-applied electrode and the surface to be charged; and generating a dc electric field between the solid state corona discharger and said surface to be charged; as well as by initiating corona discharge between an ac electrode and a dc-applied electrode.