Patent US3754137A successfully refreshed from Google Patents.
US3754137A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Corona discharge device
Assignee: Konica Minolta Inc
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Filing: 1971-03-16
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Granted: 1973-08-21
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Expires: 1991-03-16
Abstract
Abstract A corona discharge device for use in electrophotography and electrostatic printing apparatuses is provided having a corona discharge electrode, a shielding back plate with a corona discharge aperture and one or more conductive plates. Each of the conductive plates is insulated from the remainder of the apparatus and positioned adjacent to the aperture. A potential is impressed on each of these plates during corona discharge to prevent dust and other foreign particles from entering through the aperture and adhering to the electrode.
Inventors
- 👤 N Kamogawa
- 👤 M Okumura
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 16:32
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/02; G03G15/0291
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
123 words
A corona discharge device for use in electrophotographic and electroprinting apparatus of the type having insulating photoconductive material comprising corona discharge electrode means, a shielding member comprising grounded conductive material surrounding said corona discharge electrode means, said grounded conductive material having an aperture therein to permit corona charging of said insulating photoconductive material, at least one conductive plate insulated from the corona discharge device, said at least one conductive plate being positioned adjacent to said aperture parallel to and in electric field forming relationship to said insulating photoconductive material, said at least one conductive plate having a sufficient D.C. potential impressed thereon during corona discharge such that said field is sufficient to prevent the entry of dust and foreign particles through said aperture.
Claim 2
Dependent Claim
123 words
A corona discharge device for use in electrophotographic and electroprinting apparatus of the type having insulating photoconductive material comprising corona discharge electrode means, a shielding member comprising grounded conductive material surrounding said corona discharge electrode means, said grounded conductive material having an aperture therein to permit corona charging of said insulating photoconductive material, at least one conductive plate insulated from the corona discharge device, said at least one conductive plate being positioned adjacent to said aperture parallel to and in electric field forming relationship to said insulating photoconductive material, said at least one conductive plate having a sufficient D.C. potential impressed thereon during corona discharge such that said field is sufficient to prevent the entry of dust and foreign particles through said aperture.
Claim 3
Dependent Claim
25 words
The apparatus specified in claim 1 further comprising D.C. power supply means connected to said at least one conductive plate for supplying said D.C. potential.
Claim 4
Dependent Claim
14 words
The apparatus specified in claim 1 further comprising a plurality of said conductive plates.
Claim 5
Dependent Claim
22 words
The apparatus specified in claim 1 further comprising insulating material mounted between said at least one conductive plate and said shielding member.
Claim 6
Dependent Claim
30 words
The apparatus specified in claim 1 wherein said D.C. potential is impressed on said at least one conductive plate by the corona discharge electrode wheN operating in the discharge mode.
Claim 7
Dependent Claim
18 words
The apparatus specified in claim 1 wherein said at least one conductive plate is positioned outside said aperture.
References Cited (Backward Citations)
US3339069A
Cited
US3496352A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-08-20 | 1977-02-19 | 1977-08-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-08-20 | 1981-02-19 | 1981-08-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-08-20 | 1985-02-19 | 1985-08-21 | $7700.00 | Window Closed / Lapsed |