Scorotron charging apparatus

Abstract

A plurality of parallel wires (27) are disposed between a corona discharge electrode (24) and a surface (13) to be electrostatically charged. The surface (13) is moved relative to the electrode (24) and wires (27). The wires (27) are equally spaced from each other in a plane (28) which is inclined relative to the surface (13) in such a manner that the spacing between the wires (27) and the surface (13) increases in the direction of movement of the surface (13) relative to the wires (27). A high voltage for corona discharge is applied to the electrode (24). A low voltage is applied to the wires (27) to prevent the surface (13) from being charged above a predetermined potential. The low voltage may be applied to the wires (27) by means of a zener diode (31) connected between the wires (27) and ground which prevents a potential induced in the wires (27) from the electrode (24) from exceeding the zener voltage of the diode (31).

Dependencies are inferred from the claim text.