US3789278A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Corona charging device
Assignee: International Business Machines Corp
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Filing: 1972-12-20
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Granted: 1974-01-29
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Expires: 1992-12-20
Abstract
Abstract A negatively biased corona discharge system includes a conductive electrode having a thin inorganic dielectric outer layer bonded thereto which is employed as a corona discharge electrode. The discharge system is utilized for uniformly placing a negative charge on an insulator substrate such as an electrophotographic imaging surface. The coating on the electrode acts to suppress the widely spaced emission nodes common to all negatively biased metal corona discharge electrodes. The coated electrode may, therefore, be placed in close proximity to the substrate which it is charging and operated at low emission densities without sacrificing charge uniformity thereby reducing the power requirement of the corona discharge system.
Inventors
- 👤 R Bingham
- 👤 G Poquette
- 👤 T Cecil
- 👤 G Galli
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 00:58
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/02; G03G15/0291
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
64 words
A negative corona discharge system including: a corona discharge electrode comprising a core having at least an outer conductive layer and a thin layer of a metal oxide dielectric material intimately bonded to the outer periphery of said conductive layer; a negative direct current potential source connected to said corona discharge electrode for generating a uniform negative corona discharge from said corona discharge electrode.
Claim 2
Dependent Claim
64 words
A negative corona discharge system including: a corona discharge electrode comprising a core having at least an outer conductive layer and a thin layer of a metal oxide dielectric material intimately bonded to the outer periphery of said conductive layer; a negative direct current potential source connected to said corona discharge electrode for generating a uniform negative corona discharge from said corona discharge electrode.
Claim 3
Dependent Claim
18 words
The negative corona discharge system set forth in claim 1 wherein said core consists of conductive metallic material.
Claim 4
Dependent Claim
37 words
The negative corona discharge system set forth in claim 1 wherein said outer conductive layer consists of a metallic material and wherein said metal oxide is an oxide of the metallic material of said outer conductive layer.
Claim 5
Dependent Claim
18 words
A negative corona discharge system according to claim 3 wherein said core consists of a conductive metallic material.
Claim 6
Dependent Claim
22 words
The negative corona discharge system set forth in claim 3 wherein said core comprises aluminum and said metal oxide comprises aluminum oxide.
Claim 7
Dependent Claim
22 words
The negative corona discharge system set forth in claim 3 wherein said core comprises zinc and said metal oxide comprises zinc oxide.
Claim 8
Dependent Claim
22 words
The negative corona discharge system set forth in claim 3 wherein said core comprises magnesium and said metal oxide comprises magnesium oxide.
Claim 9
Dependent Claim
63 words
A negative corona discharge system including: a corona discharge electrode comprising a core having at least an outer conductive layer and a thin layer of a ceramic dielectric material intimately bonded to the outer periphery of said conductive layer; a negative direct current potential source connected to said corona discharge electrode for generating a uniform negative corona discharge from said corona discharge electrode.
Claim 10
Dependent Claim
63 words
A negative corona discharge system including: a corona discharge electrode comprising a core having at least an outer conductive layer and a thin layer of a ceramic dielectric material intimately bonded to the outer periphery of said conductive layer; a negative direct current potential source connected to said corona discharge electrode for generating a uniform negative corona discharge from said corona discharge electrode.
Claim 11
Dependent Claim
17 words
The negative corona discharge system set forth in claim 8 wherein said ceramic material comprises silicon nitride.
Claim 12
Dependent Claim
17 words
The negative corona discharge system set forth in claim 8 wherein said ceramic material comprises silicon dioxide.
Claim 13
Dependent Claim
18 words
The negative corona discharge system set forth in claim 8 wherein said ceramic material comprises a phosphosilicate glass.
Claim 14
Dependent Claim
125 words
An improved corona discharge electrode for imposing a uniform negative electrostatic charge on an electrophotographic plate comprising an insulating layer mounted on a conductive backing member comprising: at least one corona discharge electrode adjacent to and spaced from said insulating layer, said corona discharge electrode comprising a core having at least an outer layer of metal and a thin layer of a metal oxide dielectric material intimately bonded to said outer metal layer; a negative direct current potential source connected to said corona discharge electrode to provide a negative potential between said corona discharge electrode and said conductive backing member for generating a negative corona discharge from said corona discharge electrode thereby imposing a uniform electrostatic charge on said insulating Layer of said electrophotographic plate.
Claim 15
Dependent Claim
125 words
An improved corona discharge electrode for imposing a uniform negative electrostatic charge on an electrophotographic plate comprising an insulating layer mounted on a conductive backing member comprising: at least one corona discharge electrode adjacent to and spaced from said insulating layer, said corona discharge electrode comprising a core having at least an outer layer of metal and a thin layer of a metal oxide dielectric material intimately bonded to said outer metal layer; a negative direct current potential source connected to said corona discharge electrode to provide a negative potential between said corona discharge electrode and said conductive backing member for generating a negative corona discharge from said corona discharge electrode thereby imposing a uniform electrostatic charge on said insulating Layer of said electrophotographic plate.
Claim 16
Dependent Claim
25 words
The improved corona discharge electrode of claim 12 wherein said metal oxide dielectric material is a metal oxide of the metal of said outer layer.
Claim 17
Dependent Claim
124 words
An improved corona discharge electrode for imposing a uniform negative electrostatic charge on an electrophotographic plate comprising an insulating layer mounted on a conductive backing member comprising: at least one corona discharge electrode adjacent to and spaced from said insulating layer, said corona discharge electrode comprising a core having at least an outer layer of metal and a thin ayer of a ceramic dielectric material intimately bonded to said outer metal layer; a negative direct current potential source connected to said corona discharge electrode to provide a negative potential between said corona discharge electrode and said conductive backing member for generating a negative corona discharge from said corona discharge electrode thereby improsing a uniform electrostatic charge on said insulating layer of said electrophotographic plate.
Claim 18
Dependent Claim
124 words
An improved corona discharge electrode for imposing a uniform negative electrostatic charge on an electrophotographic plate comprising an insulating layer mounted on a conductive backing member comprising: at least one corona discharge electrode adjacent to and spaced from said insulating layer, said corona discharge electrode comprising a core having at least an outer layer of metal and a thin ayer of a ceramic dielectric material intimately bonded to said outer metal layer; a negative direct current potential source connected to said corona discharge electrode to provide a negative potential between said corona discharge electrode and said conductive backing member for generating a negative corona discharge from said corona discharge electrode thereby improsing a uniform electrostatic charge on said insulating layer of said electrophotographic plate.
References Cited (Backward Citations)
US3566108A
Cited
US3634726A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-01-28 | 1977-07-30 | 1978-01-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-01-28 | 1981-07-30 | 1982-01-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-01-28 | 1985-07-30 | 1986-01-29 | $7700.00 | Window Closed / Lapsed |