US4117579A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of impregnating a capacitor
Assignee: General Electric Co
•
Filing: 1977-07-20
•
Granted: 1978-10-03
•
Expires: 1997-07-20
Abstract
Abstract Between about 0.01 and 10.0% by weight of an antioxidant, and between about 0.1 and 10% by weight of an epoxide are added to a liquid aromatic ester prior to refining or purification of the ester and prior to the use of the ester to impregnate a capacitor.
Inventors
- 👤 David G. Shaw
- 👤 Vandos Shedigian
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 22:28
CPC Classifications
H; H01; H01G; H01G4/00; H01G4/002; H01G4/018; H01G4/20; H01G4/22; H01G4/221; Y; Y10; Y10T; Y10T29/00; Y10T29/43; Y10T29/435
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
98 words
The process of impregnating a capacitor with an aromatic dielectric liquid comprising a. mixing with said liquid an antioxidant in an amount of greater than about 0.01% and up to about 10.0% by weight of said liquid. b. refining the mixture including passing the mixture through a filtering process to remove impurities but to retain some antioxidant therein. c. heating said mixture to an elevated temperature. d. vacuum impregnating a capacitor with said mixture. e. and sealing said capacitor with said capacitor retaining therein from between about 0.01 to 5.0% of said antioxidant by weight of said liquid.
Claim 2
Dependent Claim
98 words
The process of impregnating a capacitor with an aromatic dielectric liquid comprising a. mixing with said liquid an antioxidant in an amount of greater than about 0.01% and up to about 10.0% by weight of said liquid. b. refining the mixture including passing the mixture through a filtering process to remove impurities but to retain some antioxidant therein. c. heating said mixture to an elevated temperature. d. vacuum impregnating a capacitor with said mixture. e. and sealing said capacitor with said capacitor retaining therein from between about 0.01 to 5.0% of said antioxidant by weight of said liquid.
Claim 3
Dependent Claim
12 words
The process of claim 1 wherein said liquid includes a diaryl sulfone.
Claim 4
Dependent Claim
45 words
The process of claim 2 wherein an epoxide in an amount greater than about 0.01% up to about 10.0% by weight is added to said liquid prior to said refining and between about 0.01 and 5.0% by weight of said epoxide remains in said capacitor.
Claim 5
Dependent Claim
22 words
The process of claim 3 wherein said liquid is a branch chain phthalate ester and said temperature is above about 70° C.
Claim 6
Dependent Claim
20 words
The process as recited in claim 4 wherein said antioxidant is taken from the class of hindered phenols and quinones.
Claim 7
Dependent Claim
23 words
The process of claim 5 wherein the mixture in the said mixing, refining, heating and vacuum impregnation steps is maintained under vacuum conditions.
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) | 1981-10-02 | 1982-04-03 | 1982-10-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-10-02 | 1986-04-03 | 1986-10-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-10-02 | 1990-04-03 | 1990-10-03 | $7700.00 | Window Closed / Lapsed |