US3649830A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Uniform charging method and apparatus using an array of needle electrodes
Assignee: Xerox Corp
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Filing: 1970-11-03
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Granted: 1972-03-14
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Expires: 1990-11-03
Abstract
Abstract Charging method and apparatus for applying a uniform charge to a surface in which an array of needle electrodes is moved relative to the surface, and a source of relatively high electric potential is coupled to alternate ones of the electrodes on each pass in inverse order. The remaining alternate electrodes are coupled to a source of relatively low electric potential or ground. By switching the potentials on each pass a uniform charge is obtained. In one embodiment a lattice-type arrangement is utilized with alternate rows of electrodes offset from an adjacent row to provide the desired uniform charge.
Inventors
- 👤 Masamichi Sato
- 👤 Isoji Takahashi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 10:04
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/02; G03G15/0291
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
111 words
Charging apparatus for applying a uniform electrostatic charge to a surface comprising a linear array of needle electrodes uniformly spaced and extending perpendicular to a surface to be charged, means for causing relative movement between said electrodes and the surface to be charged, and circuit means for coupling a source of relatively high DC electric potential to alternate ones of said electrodes and an electric potential substantially at ground to the remaining electrodes, said means for causing relative movement operates to reciprocate the electrodes past the surface to be charged, and said circuit means is operative to inverse the different potentials coupled to alternate ones of the electrodes upon each pass.
Claim 2
Dependent Claim
111 words
Charging apparatus for applying a uniform electrostatic charge to a surface comprising a linear array of needle electrodes uniformly spaced and extending perpendicular to a surface to be charged, means for causing relative movement between said electrodes and the surface to be charged, and circuit means for coupling a source of relatively high DC electric potential to alternate ones of said electrodes and an electric potential substantially at ground to the remaining electrodes, said means for causing relative movement operates to reciprocate the electrodes past the surface to be charged, and said circuit means is operative to inverse the different potentials coupled to alternate ones of the electrodes upon each pass.
Claim 3
Dependent Claim
83 words
Charging apparatus for applying a uniform electrostatic charge to a surface comprising an array of needle electrodes arranged in lattice form overlying a surface to be charged, a source of relatively high DC electric potential coupled to alternate rows of said electrodes and electric potential substantially at ground coupled to the remaining rows of said electrodes, means for causing reciprocal passing movement between said electrodes and the surface to be charged, and circuit means for switching potentials of said electrodes on each pass.
Claim 4
Dependent Claim
83 words
Charging apparatus for applying a uniform electrostatic charge to a surface comprising an array of needle electrodes arranged in lattice form overlying a surface to be charged, a source of relatively high DC electric potential coupled to alternate rows of said electrodes and electric potential substantially at ground coupled to the remaining rows of said electrodes, means for causing reciprocal passing movement between said electrodes and the surface to be charged, and circuit means for switching potentials of said electrodes on each pass.
Claim 5
Independent Claim
69 words
A method of uniformly charging a xerographic surface comprising the steps of alternatively arranging needle electrodes coupled to a relatively high source of DC potential and an electric potential substantially at ground in overlying relation to a surface to be charged, moving the electrodes relative to the surface to be charged in reciprocating scanning movements, and interchanging the potentials coupled to the electrodes in approximately half of such movements.
Claim 6
Independent Claim
69 words
A method of uniformly charging a xerographic surface comprising the steps of alternatively arranging needle electrodes coupled to a relatively high source of DC potential and an electric potential substantially at ground in overlying relation to a surface to be charged, moving the electrodes relative to the surface to be charged in reciprocating scanning movements, and interchanging the potentials coupled to the electrodes in approximately half of such movements.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-03-14 | 1975-09-13 | 1976-03-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-03-14 | 1979-09-13 | 1980-03-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-03-14 | 1983-09-13 | 1984-03-14 | $7700.00 | Window Closed / Lapsed |