Patent US4304880A successfully refreshed from Google Patents.
US4304880A
Expired / Lapsed
US
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Insulating coating for transformer wires
Assignee: General Electric Co
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Filing: 1980-04-28
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Granted: 1981-12-08
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Expires: 2000-04-28
Abstract
Abstract Improved three component insulating coatings for both wet solvent and dry electrostatic application to transformer wires contain an increased eopoxy resin concentration and a decreased amount of polyvinyl acetal and phenol aldehyde resins. The increased epoxy content gives substantially improved coatings with no adverse dissipation and hydrolytic effects. The epoxy constituent can range from 30-60 per cent by weight providing the ratio of the polyvinyl acetal to phenol aldehyde is kept within the range from 1 to 1 to 2 to 1.
Inventors
- 👤 Ralph G. Flowers
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 16:34
CPC Classifications
H; H01; H01F; H01F27/00; H01F27/28; H01F27/32; H01F27/323; C; C09; C09D; C09D129/00; C09D129/14; C09D161/00; C09D161/04; C09D161/06; C09D163/00; H01B; H01B3/00; H01B3/18; H01B3/30; H01B3/36; H01B3/40; H01B3/42; H01B3/428; Y; Y10; Y10T; Y10T428/00; Y10T428/29; Y10T428/2913; Y10T428/2933
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
53 words
An improved transformer insulating wire coating composition of the type containing phenol aldehyde resin, polyvinyl acetal resin, and epoxy resin, the improvement which comprises the composition defined within the accompanying triaxial diagram of FIG. 5 and and including 1 to 10 percent by weight of said epoxy resin of an epoxy curing agent.
Claim 2
Dependent Claim
53 words
An improved transformer insulating wire coating composition of the type containing phenol aldehyde resin, polyvinyl acetal resin, and epoxy resin, the improvement which comprises the composition defined within the accompanying triaxial diagram of FIG. 5 and and including 1 to 10 percent by weight of said epoxy resin of an epoxy curing agent.
Claim 3
Dependent Claim
66 words
An improved transformer insulating coating composition of the type containing phenol aldehyde resin, polyvinyl acetal resin, and epoxy resin the improvement which comprises: 30 to 60 weight percent of the epoxy resin and a ratio of the polyvinyl acetal to the phenol aldehyde within a range of 1.10 to 1.90, and 1 to 10 percent by weight of said epoxy resin of an epoxy curing agent.
Claim 4
Dependent Claim
66 words
An improved transformer insulating coating composition of the type containing phenol aldehyde resin, polyvinyl acetal resin, and epoxy resin the improvement which comprises: 30 to 60 weight percent of the epoxy resin and a ratio of the polyvinyl acetal to the phenol aldehyde within a range of 1.10 to 1.90, and 1 to 10 percent by weight of said epoxy resin of an epoxy curing agent.
References Cited (Backward Citations)
USRE25625E
Cited
US3239598A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-12-07 | 1985-06-08 | 1985-12-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-12-07 | 1989-06-08 | 1989-12-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-12-07 | 1993-06-08 | 1993-12-08 | $7700.00 | Window Closed / Lapsed |