US4293433A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Perchloroethylene dielectric fluid containing pyrrole and phenol
Assignee: OCCIDENTIAL ELECTROCHEMICALS Corp
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Filing: 1980-06-02
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Granted: 1981-10-06
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Expires: 2000-06-02
Abstract
Abstract Electrical devices such as transformers and power capacitors are improved by the use of a dielectric fluid prepared by combining perchloroethylene having a low chlorinated ethane content with an antioxidant. This fluid has excellent resistance to decomposition over long periods of time and under severe operational conditions.
Inventors
- 👤 Jack A. Borror
- 👤 Edward A. Rowe, Jr.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 00:05
CPC Classifications
H; H01; H01F; H01F27/00; H01F27/28; H01F27/32; H01F27/321; H01B; H01B3/00; H01B3/18; H01B3/20; H01B3/24
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
53 words
In an electrical device containing a dielectric fluid, the improvement which comprises employing as the dielectric fluid a perchloroethylene composition which is resistant to decomposition at elevated temperatures in the presence of oxygen, containing less than about 0.005 percent of chlorinated ethanes, and a synergistic mixture of N-methyl pyrrole and p-tertiary amyl phenol.
Claim 2
Dependent Claim
53 words
In an electrical device containing a dielectric fluid, the improvement which comprises employing as the dielectric fluid a perchloroethylene composition which is resistant to decomposition at elevated temperatures in the presence of oxygen, containing less than about 0.005 percent of chlorinated ethanes, and a synergistic mixture of N-methyl pyrrole and p-tertiary amyl phenol.
Claim 3
Dependent Claim
29 words
The device of claim 1 wherein the perchloroethylene contains from about 0.0005 to about 0.02 percent N-methyl pyrrole and from about 0.0001 to about 0.01 percent p-tertiary amyl phenol.
Claim 4
Dependent Claim
25 words
The device of claim 1 wherein the perchloroethylene contains at least about 0.0025 percent N-methyl pyrrole and at least about 0.0005 percent p-tertiary amyl phenol.
Claim 5
Dependent Claim
12 words
The device of claim 1 wherein the electrical device is a transformer.
Claim 6
Independent Claim
44 words
A method of preparing an improved dielectric fluid, resistant to decomposition at elevated temperatures in the presence of oxygen, which method comprises combining perchloroethylene which contains less than about 0.005 percent chlorinated ethanes with a synergistic mixture of N-methyl pyrrole and p-tertiary amyl phenol.
Claim 7
Independent Claim
44 words
A method of preparing an improved dielectric fluid, resistant to decomposition at elevated temperatures in the presence of oxygen, which method comprises combining perchloroethylene which contains less than about 0.005 percent chlorinated ethanes with a synergistic mixture of N-methyl pyrrole and p-tertiary amyl phenol.
Claim 8
Dependent Claim
31 words
The method of claim 5 wherein the perchloroethylene is combined with from about 0.0005 to about 0.02 percent N-methyl pyrrole and from about 0.0001 to about 0.01 percent p-tertiary amyl phenol.
Claim 9
Dependent Claim
27 words
The method of claim 5 wherein the perchloroethylene is combined with at least about 0.0025 percent N-methyl pyrrole and at least about 0.0005 percent p-tertiary amyl phenol.
Claim 10
Dependent Claim
38 words
A dielectric fluid composition which is resistant to decomposition at elevated temperatures in the presence of oxygen, comprising perchlorethylene containing less than about 0.005 percent chlorinated ethanes, and a synergistic mixture of N-methyl pyrrole and p-tertiary amyl phenol.
Claim 11
Dependent Claim
38 words
A dielectric fluid composition which is resistant to decomposition at elevated temperatures in the presence of oxygen, comprising perchlorethylene containing less than about 0.005 percent chlorinated ethanes, and a synergistic mixture of N-methyl pyrrole and p-tertiary amyl phenol.
Claim 12
Dependent Claim
29 words
The composition of claim 8 wherein the perchloroethylene contains from about 0.0005 to about 0.02 percent N-methyl pyrrole and from about 0.0001 to about 0.01 percent p-tertiary amyl phenol.
Claim 13
Dependent Claim
25 words
The composition of claim 8 wherein the perchloroethylene contains at least about 0.0025 percent N-methyl pyrrole and at least about 0.0005 percent p-tertiary amyl phenol.
Claim 14
Dependent Claim
17 words
In a transformer, the improvement which comprises insulation material comprising the dielectric fluid composition of claim 10.
Claim 15
Independent Claim
35 words
An apparatus comprising an electrical device and a dielectric fluid composition, said dielectric fluid comprising perchlorethylene containing less than about 0.005 percent chlorinated ethanes, and a synergistic mixture of N-methyl pyrrole and p-tertiary amyl phenol.
Claim 16
Independent Claim
35 words
An apparatus comprising an electrical device and a dielectric fluid composition, said dielectric fluid comprising perchlorethylene containing less than about 0.005 percent chlorinated ethanes, and a synergistic mixture of N-methyl pyrrole and p-tertiary amyl phenol.
Claim 17
Independent Claim
52 words
An apparatus comprising a container, an electrical device therein, a dielectric fluid composition comprising perchloroethylene surrounding said device, said perchloroethylene being resistant to decomposition at elevated temperature in the presence of oxygen and containing less than about 0.005 percent chlorinated ethanes, and a synergistic mixture of N-methyl pyrrole and p-tertiary amyl phenol.
Claim 18
Independent Claim
52 words
An apparatus comprising a container, an electrical device therein, a dielectric fluid composition comprising perchloroethylene surrounding said device, said perchloroethylene being resistant to decomposition at elevated temperature in the presence of oxygen and containing less than about 0.005 percent chlorinated ethanes, and a synergistic mixture of N-methyl pyrrole and p-tertiary amyl phenol.
Claim 19
Independent Claim
44 words
A method of insulating an electrical device which comprises surrounding said device with a fluid composition especially adapted for use as a dielectric, comprising perchloroethylene containing less than about 0.005 percent chlorinated ethanes, and a synergistic mixture of N-methyl pyrrole and p-tertiary amyl phenol.
Claim 20
Independent Claim
44 words
A method of insulating an electrical device which comprises surrounding said device with a fluid composition especially adapted for use as a dielectric, comprising perchloroethylene containing less than about 0.005 percent chlorinated ethanes, and a synergistic mixture of N-methyl pyrrole and p-tertiary amyl phenol.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-10-05 | 1985-04-06 | 1985-10-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-10-05 | 1989-04-06 | 1989-10-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-10-05 | 1993-04-06 | 1993-10-06 | $7700.00 | Window Closed / Lapsed |