Patent US3737712A successfully refreshed from Google Patents.
US3737712A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Sparkgap assembly having a semi-conductive coating adjacent the electrodes thereof
Assignee: General Electric Co
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Filing: 1971-11-17
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Granted: 1973-06-05
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Expires: 1991-11-17
Abstract
Abstract A surge voltage arrester sparkgap assembly having a plurality of horngap electrodes is provided with a coating of high resistance, electrically conductive material mounted adjacent the outermost ends of the electrodes. The coating of conductive material is effective to form high resistance electrical circuits between the respective ends of the electrodes and any electrically conductive metal particles that may be eroded from the electrodes and splattered onto the internal insulating surfaces of the sparkgap assembly. These high resistance electrically conductive circuits prevent the formation of a corona discharge between the electrodes and any such conductive particles.
Inventors
- 👤 T Hall
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 07:12
CPC Classifications
H; H01; H01T; H01T4/00; H01T4/16
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
156 words
A sparkgap assembly for an over voltage surge arrester comprising an insulating housing, wall means arranged to define an arcing chamber within said housing, a pair of electrodes mounted in spaced-apart relationship to define a sparkgap therebetween within said arcing chamber, electric circuit means connected to said electrodes for transmitting an over voltage surge to the electrodes, said electrodes being formed to have arc-running surfaces along which arcs are movable away from said sparkgap, and a coating of high resistance electrically conductive material mounted on said wall means adjacent to and extending beyond the sides of a portion of the arc running surfaces of each of said electrodes, said coating being operable to form an electrical circuit between the arc-running surfaces of said electrodes and any electrically conductive particle lodged on said wall means in contact with the coating thereby to prevent the formation of a high voltage electrical field between the electrode and said particle.
Claim 2
Dependent Claim
156 words
A sparkgap assembly for an over voltage surge arrester comprising an insulating housing, wall means arranged to define an arcing chamber within said housing, a pair of electrodes mounted in spaced-apart relationship to define a sparkgap therebetween within said arcing chamber, electric circuit means connected to said electrodes for transmitting an over voltage surge to the electrodes, said electrodes being formed to have arc-running surfaces along which arcs are movable away from said sparkgap, and a coating of high resistance electrically conductive material mounted on said wall means adjacent to and extending beyond the sides of a portion of the arc running surfaces of each of said electrodes, said coating being operable to form an electrical circuit between the arc-running surfaces of said electrodes and any electrically conductive particle lodged on said wall means in contact with the coating thereby to prevent the formation of a high voltage electrical field between the electrode and said particle.
Claim 3
Dependent Claim
35 words
An invention as defined in claim 1 wherein said electrodes comprise horngap electrodes, and wherein said coating comprises two disconnected coating patches that are mounted respectively adjacent the outermost ends of each of said electrodes.
Claim 4
Dependent Claim
51 words
An invention as defined in claim 2 wherein said coating has an electrical resistance of at least 5,000 ohms per square unit thereof, whereby the magnitude of current caused to flow from said particle to the electrode adjacent it is limited as a direct function of the resistance of the coating.
Claim 5
Dependent Claim
55 words
An invention as defined in claim 3 wherein said coating has an electrical resistance no greater than 100,000 ohms per square unit thereof, thereby to afford a current conducting path that effectively shunts the air gap between said particle and the electrode adjacent to it and thereby prevents a corona discharge across said air gap.
Claim 6
Dependent Claim
24 words
An invention as defined in claim 4 wherein said coating is at least 2 mils thick throughout a major portion of its surface area.
Claim 7
Dependent Claim
69 words
An invention as defined in claim 4 wherein said wall means comprise a pair of juxtaposed insulating plates formed of granular insulating material having air vent passageways through the interstices of its granules, said coating being formed of an air curable material that is liquid in its uncured state and possesses sufficient viscosity to prevent it from penetrating more than 100 mils through the interstices of said wall means.
References Cited (Backward Citations)
US2143853A
Cited
US3354345A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-06-04 | 1976-12-04 | 1977-06-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-06-04 | 1980-12-04 | 1981-06-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-06-04 | 1984-12-04 | 1985-06-05 | $7700.00 | Window Closed / Lapsed |