US3813548A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Corona generating methods and apparatus therefor
Assignee: Xerox Corp
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Filing: 1972-08-23
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Granted: 1974-05-28
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Expires: 1992-08-23
Abstract
Abstract Improved corona generating methods and apparatus therefor are provided in accordance with the teachings of this invention wherein a medium in relative motion with a charging station may be rapidly charged to a desired potential in a highly efficient manner. According to one embodiment of the present invention, corona charging apparatus including at least one coronode and having a shield associated therewith is provided and operated in such manner that current flow in the shield is maintained above a selected minimum level during the operation of the corona charging apparatus. The selected minimum level of current flow in the shield is of such value that the coronode will initially supply ion current with a substantially lower threshold energizing potential applied thereto than would be otherwise available and the directivity of the selected minimum level of current flow is such that the potential established at the shield will ensure that a majority of the ion charging current produced at the coronode is delivered to the medium to be charged.
Inventors
- 👤 M Silverberg
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 08:40
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/02; G03G15/0291
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
143 words
In corona generating apparatus including at least one coronode means, shield means associated with said coronode means and means for applying a potential between said at least one coronode means and a medium to be charged to cause ion current flow from said coronode means, the improvement comprising means for connecting said shield means to a reference potential through current limiting resistor means, said current limiting resistor means exhibiting a value of resistance which is equal to or exceeds the dynamic resistance exhibited between said at least one coronode means and said shield means, said resistor means limiting the current flow from said shield means to said reference potential to a minimum value of substantially one microampere per inch, whereby a major portion of said ion current flow from said at least one coronode means is delivered to the medium to be charged.
Claim 2
Dependent Claim
143 words
In corona generating apparatus including at least one coronode means, shield means associated with said coronode means and means for applying a potential between said at least one coronode means and a medium to be charged to cause ion current flow from said coronode means, the improvement comprising means for connecting said shield means to a reference potential through current limiting resistor means, said current limiting resistor means exhibiting a value of resistance which is equal to or exceeds the dynamic resistance exhibited between said at least one coronode means and said shield means, said resistor means limiting the current flow from said shield means to said reference potential to a minimum value of substantially one microampere per inch, whereby a major portion of said ion current flow from said at least one coronode means is delivered to the medium to be charged.
Claim 3
Dependent Claim
46 words
The improved corona generating apparatus according to claim 1 wherein said current limiting resistor means acts to limit current flow from said shield means to said reference potential to a value substantially within a range of from 1 microampere per inch to 10 microamperes per inch.
Claim 4
Dependent Claim
65 words
The improved corona generating apparatus according to claim 2 additionally comprising insulating means positioned intermediate said coronode means and said shield means, said insulating means being disposed on a surface of said shield means proximate to said coronode means, whereupon said coronode means may be positioned in a physically close relationship to said surface of said shield means upon which said insulating means is disposed.
Claim 5
Independent Claim
148 words
The method of charging a medium with corona generating apparatus including at least one coronode means and shield means associated with said at least one coronode means, comprising the steps of: applying a potential between said at least one coronode means and said medium to be charged to cause ion current flow from said coronode means; and establishing a current path between said shield means and a reference potential through current limiting resistor means, said current limiting resistor means manifesting a value of resistance equal to or greater than the dynamic resistance exhibited between said at least one coronode means and said shield means, said resistor means limiting the current flow along said path to a minimum value of substantially 1 microampere per inch, whereby a major portion of said ion current flow from said at least one coronode means is delivered to the medium to be charged.
Claim 6
Independent Claim
148 words
The method of charging a medium with corona generating apparatus including at least one coronode means and shield means associated with said at least one coronode means, comprising the steps of: applying a potential between said at least one coronode means and said medium to be charged to cause ion current flow from said coronode means; and establishing a current path between said shield means and a reference potential through current limiting resistor means, said current limiting resistor means manifesting a value of resistance equal to or greater than the dynamic resistance exhibited between said at least one coronode means and said shield means, said resistor means limiting the current flow along said path to a minimum value of substantially 1 microampere per inch, whereby a major portion of said ion current flow from said at least one coronode means is delivered to the medium to be charged.
Claim 7
Dependent Claim
96 words
In a corona generating apparatus including at least one coronode means, shield means associated with said coronode means and means for applying a potential between said at least one coronode means and the medium to be charged to cause ion current flow from said coronode means, the improvement comprising: means electrically connected to said shield means for maintaining a current in said shield means of a predetermined minimum value sufficient to cause a major portion of said ion current flow from said at least one coronode means to be delivered to said medium to be charged.
Claim 8
Dependent Claim
96 words
In a corona generating apparatus including at least one coronode means, shield means associated with said coronode means and means for applying a potential between said at least one coronode means and the medium to be charged to cause ion current flow from said coronode means, the improvement comprising: means electrically connected to said shield means for maintaining a current in said shield means of a predetermined minimum value sufficient to cause a major portion of said ion current flow from said at least one coronode means to be delivered to said medium to be charged.
Claim 9
Dependent Claim
19 words
The improved corona generating apparatus of claim 5, wherein said predetermined minimum value equals approximately 1 microampere per inch.
Claim 10
Dependent Claim
35 words
The improved corona generating apparatus of claim 5, wherein the current in said shield means is maintained at a value substantially within a range of from 1 microampere per inch to 10 microamperes per inch.
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) | 1977-05-27 | 1977-11-26 | 1978-05-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-05-27 | 1981-11-26 | 1982-05-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-05-27 | 1985-11-26 | 1986-05-28 | $7700.00 | Window Closed / Lapsed |