Patent US3836705A successfully refreshed from Google Patents.
US3836705A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrical insulator and conducting tar therefor
Assignee: CA PORCELAIN CO Ltd
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Filing: 1972-12-14
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Granted: 1974-09-17
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Expires: 1992-12-14
Abstract
Abstract A conducting tar coating is placed on the surfaces of the conductive hardware of an insulator, and on the surfaces of an insulator shell connected to the hardware by a cement. The insulator surface has a semiconducting coating. The conducting tar is formed by admixing carbon black in an asphalt base after dissolving the asphalt with a suitable solvent.
Inventors
- 👤 G Rosenblatt
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 23:24
CPC Classifications
H; H01; H01B; H01B17/00; H01B17/50
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
12 words
The electrical insulator of claim 1 wherein said cement layer is conductive.
Claim 2
Dependent Claim
39 words
The electrical insulator of claim 2 wherein a second tar coating is formed on said first surface region of said conductive hardware member and is disposed between said first surface region of said hardware member and said cement layer.
Claim 3
Dependent Claim
20 words
The electrical insulator of claim 2 wherein said tar coating consists of an asphalt base having carbon black admixed therein.
Claim 4
Dependent Claim
20 words
The electrical insulator of claim 1 wherein said tar coating consists of an asphalt base having carbon black admixed therein.
Claim 5
Dependent Claim
26 words
The electrical insulator of claim 5 wherein said tar coating contains carbon black from 20 percent to 40 percent by weight of said tar plus carbon.
Claim 6
Dependent Claim
22 words
The electrical insulator of claim 6 wherein said tar coating contains about 32 percent to 38 percent by weight of carbon black.
Claim 7
Dependent Claim
83 words
An electrical insulator comprising first and second metal members, an insulation member having a semiconducting glaze coating, a conductive tar coating on respective given surface regions of said first and second metal members and on first and second spaced regions of said insulation member and in contact with said semiconducting glaze coating, and first and second conductive cement layers connecting said given surface regions of said first and second metal members to said first and second spaced regions respectively of said insulation member.
Claim 8
Dependent Claim
32 words
The insulator of claim 8 wherein said insulator is a suspension insulator and wherein said first metal member is a metal cap and wherein said second metal member is a metal pin.
Claim 9
Dependent Claim
21 words
The insulator of claim 9 wherein said conductive tar coating consists of a painted asphalt layer having carbon black admixed therein.
Claim 10
Dependent Claim
24 words
The insulator of claim 10 wherein said carbon black forms from 20 percent to 40 percent by weight of said conductive tar plus carbon.
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) | 1977-09-16 | 1978-03-18 | 1978-09-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-09-16 | 1982-03-18 | 1982-09-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-09-16 | 1986-03-18 | 1986-09-17 | $7700.00 | Window Closed / Lapsed |