US3885203A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Excess voltage arresters
Assignee: DUBILIER INTERNATIONAL PLC DUBILIER HOUSE RADLEY RD ABINGDON OXFORDSHIRE OX14 3XA ENGLAND A BRITISH Co
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Filing: 1974-03-21
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Granted: 1975-05-20
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Expires: 1994-03-21
Abstract
Abstract An excess voltage arrester comprising a pair of spaced electrodes housed in a gas-filled enclosure wherein the electrodes carry sleeves of electrically insulating material to prevent reduction of the d.c. ignition voltage of the arrester due to the formation of conductive coatings on the internal surfaces of insulating portions of the envelope by sputtering from the discharge occurring in the arrester in operation.
Inventors
- 👤 Basil Offor Baker
- 👤 John William Ellis Ross
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 14:33
CPC Classifications
H; H01; H01T; H01T1/00; H01T1/20; H01T1/22
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
140 words
An excess voltage arrester comprising: a hollow cylindrical gas filled enclosure comprising a tubular electrically conductive central portion, a pair of electrically conductive end portions, and a pair of tubular electrically insulating portions by means of which said end portions are respectively sealed to and spaced from said central portion; a pair of spaced electrodes housed within the enclosure for which said end portions serve as respective terminals, said electrodes extending towards one another through said insulating portion of the enclosure so that the gap between the electrodes lies within the central portion of the enclosure; and a pair of sleeves of electrically insulating material carried on said electrodes respectively, each sleeve extending from a point near the inner end of the associated electrode to a point within the insulating portion of the enclosure through which the associated electrode extends.
Claim 2
Dependent Claim
140 words
An excess voltage arrester comprising: a hollow cylindrical gas filled enclosure comprising a tubular electrically conductive central portion, a pair of electrically conductive end portions, and a pair of tubular electrically insulating portions by means of which said end portions are respectively sealed to and spaced from said central portion; a pair of spaced electrodes housed within the enclosure for which said end portions serve as respective terminals, said electrodes extending towards one another through said insulating portion of the enclosure so that the gap between the electrodes lies within the central portion of the enclosure; and a pair of sleeves of electrically insulating material carried on said electrodes respectively, each sleeve extending from a point near the inner end of the associated electrode to a point within the insulating portion of the enclosure through which the associated electrode extends.
Claim 3
Dependent Claim
35 words
An arrester according to claim 1 wherein the outer end of each said sleeve lies adjacent a section of the associated electrode which is a sliding fit in the associated insulating portion of the enclosure.
Claim 4
Dependent Claim
80 words
An arrester according to claim 1 wherein each said sleeve is effective to increase the breakdown voltage between any point on the surface of the electrode carrying that sleeve and a conductive coating which may be produced in operation on the internal surface of the adjacent insulating portion of the enclosure to a value above the d.c. ignition voltage across the gap between the inner end of that electrode and the adjacent part of the central portion of the enclosure.
Claim 5
Dependent Claim
68 words
an arrester according to claim 3 wherein each said sleeve projects inwardly beyond the inner end of the adjacent insulating portion of the enclosure by an amount sufficient to make the shortest gap, via the gas-filling, between said end and the electrode carrying that sleeve appreciably larger than the gap between the inner end of that electrode and the adjacent part of the central portion of the enclosure.
Claim 6
Dependent Claim
30 words
An arrester according to claim 4 wherein the portions of the electrodes projecting inwardly beyond the sleeves are of larger diameter than the portions of the electrodes within said sleeves.
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) | 1978-05-19 | 1978-11-18 | 1979-05-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-05-19 | 1982-11-18 | 1983-05-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-05-19 | 1986-11-18 | 1987-05-20 | $7700.00 | Window Closed / Lapsed |