Abstract Disclosed herein is a charging device for use in electrophotography, characterized by a pair of corona charging devices facing each other with a suitable intervening space permitting the passage of photosensitive paper. Each corona charging device is provided with an auxiliary electrode, and at least one corona wire disposed in a holding space of the auxiliary electrode. High DC voltages of opposite polarities are applied respectively to the corona wires, and about 400 v. of AC voltage, which has been synchronized with the ripple voltages, of the high DC voltage is applied to the auxiliary electrodes. Consequently, the loss of the high DC voltage power source is reduced and a smaller power source can be applied for the charging device. Moreover, a very uniform corona discharge can be produced over a substantial portion of the entire charging period to attain a high speed charging.
Inventors
👤 Takeo Tano
👤 Morimasa Washiashi
Bibliographic Details
Application Number—
JurisdictionUS
Data Sourcegoogle_patents
Last Synchronized2026-10-29 03:49
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/02; G03G15/0291
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
99 words
A charging device for use in electrophotography comprising a pair of corona charging devices facing each other, each corona charging device including an auxiliary electrode having a holding space, and each holding space having a corona wire disposed therein, means for applying a positive DC voltage to said corona wire of one of said corona charging devices, means for applying a negative DC voltage to said corona wire of the other corona charging device, and means for applying an AC voltage to said auxiliary electrodes, said AC voltage being in synchronization with inherent rIpple voltages of the DC voltages.
Claim 2
Dependent Claim
99 words
A charging device for use in electrophotography comprising a pair of corona charging devices facing each other, each corona charging device including an auxiliary electrode having a holding space, and each holding space having a corona wire disposed therein, means for applying a positive DC voltage to said corona wire of one of said corona charging devices, means for applying a negative DC voltage to said corona wire of the other corona charging device, and means for applying an AC voltage to said auxiliary electrodes, said AC voltage being in synchronization with inherent rIpple voltages of the DC voltages.
Claim 3
Dependent Claim
29 words
A charging device for use in electrophotography according to claim 1, wherein each corona charging device is provided with a plurality of corona wires disposed in a parallel configuration.
Claim 4
Dependent Claim
32 words
A charging device for use in electrophotography according to claim 1, wherein said means for applying an AC voltage comprises means for applying an AC voltage in the order of 400 v.
Claim 5
Dependent Claim
49 words
A charging device for use in electrophotography according to claim 1 wherein said corona charging devices are disposed with a suitable intervening space for spacing therebetween a photosensitive paper to be uniformly charged by the corona discharge emitted from said corona wires, as said paper passes through said space.