US3845307A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Combined corona and luminescent discharge
Assignee: Xerox Corp
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Filing: 1973-02-22
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Granted: 1974-10-29
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Expires: 1993-02-22
Abstract
Abstract In electrophotography, wherein electrostatic charges are provided by corona wire apparatus for discharing a photoreceptor, a combined corona and luminescent discharge is provided in a single compact arrangement by connecting to the exposed corona wire, in addition to the conventional high potential for ionization, a high current, low voltage, power supply which heats the corona wire to above approximately 800* Centigrade, making it self-luminously incandescent. Optical reflectors may be provided to further direct this light onto the photoreceptor. The wire temperature is maintained below white heat, and the wire material is selected, so as not to oxidize rapidly. Transformer or capacitor electrical isolation is provided to prevent interference between the two power supplies.
Inventors
- 👤 C Gallo
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 09:31
CPC Classifications
G; G03; G03G; G03G21/00; G03G21/06; G03G15/00; G03G15/02; G03G15/0291; G03G15/14; G03G15/16; G03G15/169
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
98 words
In electrophotographic apparatus wherein electrical corona charges are applied to a photoreceptor by corona apparatus for discharging the photoreceptor including at least one corona wire positioned adjacent the photoreceptor surface, which corona wire is provided with a high voltage for electrical air ionization by a connected high voltage supply means, the improvement comprising: high current low voltage power supply means electrically connected through said same corona wire for heating said corona wire to self-luminous incandescence, said self-luminous incandescence of said corona wire providing luminous exposure discharge of said photoreceptor surface in addition to said high voltage corona discharge.
Claim 2
Dependent Claim
98 words
In electrophotographic apparatus wherein electrical corona charges are applied to a photoreceptor by corona apparatus for discharging the photoreceptor including at least one corona wire positioned adjacent the photoreceptor surface, which corona wire is provided with a high voltage for electrical air ionization by a connected high voltage supply means, the improvement comprising: high current low voltage power supply means electrically connected through said same corona wire for heating said corona wire to self-luminous incandescence, said self-luminous incandescence of said corona wire providing luminous exposure discharge of said photoreceptor surface in addition to said high voltage corona discharge.
Claim 3
Dependent Claim
36 words
The apparatus of claim 1 further including electrical isolation means between said high current power supply means and said corona wire to electrically isolate said high current power supply means from said high voltage supply means.
Claim 4
Dependent Claim
29 words
The apparatus of claim 1 wherein said corona wire is electrically heated by said high current power supply to more than approximately 800* Centigrade, but less than white heat.
Claim 5
Dependent Claim
51 words
The apparatus of claim 2 wherein said high current power supply means is an alternating current power supply and said isolation means is a high voltage insulated transformer with a primary winding connecting with said high current power supply and a secondary winding connecting to opposing ends of said corona wire.
Claim 6
Dependent Claim
24 words
The apparatus of claim 1 further including optIcal reflector means around said corona wire for directing light from said corona wire to said photoreceptor.
Claim 7
Dependent Claim
27 words
The apparatus of claim 5 wherein said reflector is also an electrostatic shield means for said corona wire directing ionization from said corona wire toward said photoreceptor.
Claim 8
Dependent Claim
35 words
The apparatus of claim 6 wherein said optical reflector directs light angularly onto said photoreceptor at a different location than ionization is directed by said electrostatic shield, for simultaneous but spaced discharge of said photoreceptor.
Claim 9
Dependent Claim
89 words
In an electrophotographic process, a method of providing both electrical corona discharge and luminous discharge of a charged photoreceptor surface from the same apparatus comprising the steps of applying a high voltage potential to a corona wire adjacent the photoreceptor surface to generate voltage air ionization charges for said photoreceptor, and applying a low voltage high electrical current through the same corona wire to heat the wire to self-luminous incandescence, and applying said incandescence from said wire to said photoreceptor surface to provide luminous exposure discharge of said photoreceptor.
Claim 10
Dependent Claim
89 words
In an electrophotographic process, a method of providing both electrical corona discharge and luminous discharge of a charged photoreceptor surface from the same apparatus comprising the steps of applying a high voltage potential to a corona wire adjacent the photoreceptor surface to generate voltage air ionization charges for said photoreceptor, and applying a low voltage high electrical current through the same corona wire to heat the wire to self-luminous incandescence, and applying said incandescence from said wire to said photoreceptor surface to provide luminous exposure discharge of said photoreceptor.
Claim 11
Dependent Claim
25 words
The method of claim 8 wherein said wire is heated by said high current to above approximately 800* Centigrade, but to less than white heat.
Claim 12
Dependent Claim
15 words
The method of claim 8 wherein said high voltage potential comprises an alternating polarity potential.
Claim 13
Dependent Claim
22 words
The method of claim 8 wherein said incandescence from said wire is directed angularly onto said photoreceptor surface by shielding said incandescence.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-10-28 | 1978-04-29 | 1978-10-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-10-28 | 1982-04-29 | 1982-10-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-10-28 | 1986-04-29 | 1986-10-29 | $7700.00 | Window Closed / Lapsed |