US 4,029,995 A · Apparatus for producing charged particles

Abstract

In a pair of surface-shaped silent discharge electrodes opposed to each other and separated by a predetermined space therebetween, phases of alternating voltages are applied to said respective silent discharge electrodes shifted in phase with respect to each other so that a silent discharge may arise alternately on either one of the electrode surfaces. A second alternating voltage is applied between the silent discharge electrodes and is alternatingly varied at a fundamented frequency twice as high as the frequency of the first alternating voltages applied to said surface-shaped silent discharge electrodes and is not inverted in polarity during the period when the silent discharge exists on either one of the electrode surfaces. Powder particles are passed through the space which separates the pair of surface-shaped silent discharge electrodes and charged in either positive or negative polarity continuously at a high efficiency.

Claims11

Dependent claims

An apparatus for producing charged particles, comprising a pair of surface-shaped ion generating electrodes, in each of which every other one of parallel linear electrodes spaced apart at a predetermined interval are connected in common to form separate electrode groups, said parallel linear electrodes, of at least one said electrode group being coated with an insulator, and an alternating voltage is applied between said respective electrode groups, and an alternating voltage is applied between said respective electrodes;

a charging space formed between said pair of ion generating electrodes spaced in opposition to each other;
means for shifting the phases of the alternating voltages applied to the respective ion generating electrodes relative to each other;
and voltage supply means for applying between said respective ion generating electrodes another alternating voltage having a fundamental frequency twice as high as the frequency of the alternating voltage applied to the respective ion generating electrodes in such phase relationship to said latter alternating voltage that inversion of the relative voltage between said respective electrode surfaces may not occur during the period when silent discharge is arising on one of the electrode surfaces.

Dependencies are inferred from the claim text.

Apparatus for producing charged particles

Life of this patent

Apparatus for producing charged particles

Life of this patent

Abstract

Claims11