Patent US3973438A successfully refreshed from Google Patents.
US3973438A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Composition for forming thermo-particulating coating which protects electrical apparatus
Assignee: Westinghouse Electric Corp
•
Filing: 1973-08-21
•
Granted: 1976-08-10
•
Expires: 1993-08-21
Abstract
Abstract A composition is disclosed of malonic acid, a resinous carrier, and a solvent. The composition is applied to a portion of an electrical apparatus which is exposed to a fluid stream. The solvent in the composition is evaporated to produce a thermo-particulating coating. When the electrical apparatus overheats the malonic acid in the coating forms particles in the fluid stream which are detected by a monitor.
Inventors
- 👤 James D. B. Smith
- 👤 David C. Phillips
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 08:52
CPC Classifications
H; H02; H02H; H02H5/00; C; C09; C09D; C09D5/00; C09D5/26
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
102 words
In a method for protecting electrical apparatus from damage due to overheating, said apparatus including a gas stream and a monitor suitable for detecting particles in said gas stream and for emitting a signal when said particles are detected, which method comprises detecting the presence of particles in said gas stream, the particles resulting from the decomposition of a thermal-particulating coating applied to said electrical apparatus at positions exposed to said gas stream, the improvement wherein the thermal-particulating coating applied comprises malonic acid and a solution of a resinous carrier stable and solid at 80°C, the solvent in said solution being evaporated.
Claim 2
Dependent Claim
102 words
In a method for protecting electrical apparatus from damage due to overheating, said apparatus including a gas stream and a monitor suitable for detecting particles in said gas stream and for emitting a signal when said particles are detected, which method comprises detecting the presence of particles in said gas stream, the particles resulting from the decomposition of a thermal-particulating coating applied to said electrical apparatus at positions exposed to said gas stream, the improvement wherein the thermal-particulating coating applied comprises malonic acid and a solution of a resinous carrier stable and solid at 80°C, the solvent in said solution being evaporated.
Claim 3
Dependent Claim
46 words
The improved method according to claim 1 wherein in said thermal-particulating coating the amount of malonic acid is about 20 to about 250 phr and the amount of the solvent in said solution is about 25 to about 75% (by weight based on said resinous carrier).
Claim 4
Dependent Claim
43 words
The improved method according to claim 1 wherein in said thermal-particulating coating the amount of malonic acid is about 40 to about 60 phr and the amount of said solvent is about 45 to about 55% (by weight based on said resinous carrier).
Claim 5
Dependent Claim
19 words
The improved method according to claim 1 wherein in said thermal-particulating coating the resinous carrier is an epoxy resin.
Claim 6
Dependent Claim
25 words
The improved method according to claim 4 wherein the thermal-particulating coating includes about 0.1 to about 3 phr of a drier for said epoxy resin.
Claim 7
Dependent Claim
19 words
The improved method according to claim 5 wherein said drier is lead naphthenate, cobalt naphthenate, or a mixture thereof.
Claim 8
Dependent Claim
31 words
The improved method according to claim 5 wherein the thermal-particulating coating is prepared by first mixing said solution of resinous carrier and said drier and then mixing in said malonic acid.
Claim 9
Dependent Claim
19 words
The improved method according to claim 1 wherein in said thermal-particulating coating the solvent in said solution is toluene.
Claim 10
Dependent Claim
20 words
The improved method according to claim 1 wherein in said thermal-particulating coating the malonic acid is dispersed in said solution.
Claim 11
Dependent Claim
23 words
The improved method according to claim 9 wherein the particle size of said dispersed malonic acid is about 25 to about 1000 microns.
Claim 12
Dependent Claim
26 words
The improved method according to claim 1 wherein said applied thermal-particulating coating composition forms a coating on said apparatus about 1/16 to about 1/2 inches thick.
Claim 13
Dependent Claim
19 words
The improved method according to claim 1 wherein in said solution of a resinous carrier the solvent is organic.
Claim 14
Dependent Claim
19 words
The improved method according to claim 1 wherein in said thermal-particulating coating the resinous carrier is stable at 125°C.
Claim 15
Dependent Claim
60 words
In a thermal detection system for electrical apparatus cooled by a gas stream, comprising a monitor suitable for detecting the presence of particles in said gas stream and a thermal-particulating coating on a portion of said electrical apparatus exposed to said gas stream, the improvement wherein said thermal-particulating coating comprises a solid layer of a resinous carrier containing malonic acid.
Claim 16
Dependent Claim
60 words
In a thermal detection system for electrical apparatus cooled by a gas stream, comprising a monitor suitable for detecting the presence of particles in said gas stream and a thermal-particulating coating on a portion of said electrical apparatus exposed to said gas stream, the improvement wherein said thermal-particulating coating comprises a solid layer of a resinous carrier containing malonic acid.
Claim 17
Dependent Claim
21 words
The improved thermal detection system according to claim 14 wherein in said thermal-particulating coating said resinous carrier is an epoxy resin.
Claim 18
Dependent Claim
27 words
The improved thermal detection system according to claim 15 wherein said thermal-particulating coating includes about 0.1 to about 3 phr of a drier for said epoxy resin.
Claim 19
Dependent Claim
21 words
The improved thermal detection system according to claim 16 wherein said drier is lead naphthenate, cobalt naphthenate, or a mixture thereof.
Claim 20
Dependent Claim
27 words
The improved thermal detection system according to claim 14 wherein said thermal-particulating coating is a solid layer on said apparatus about 1/16 to about 1/2 inches thick.
Claim 21
Dependent Claim
17 words
The improved thermal detection system according to claim 14 wherein said resinous carrier is stable at 125°C.
References Cited (Backward Citations)
US2928791A
Cited
US3316197A
Cited
US3329022A
Cited
US3427880A
Cited
US3573460A
Cited
US3845662A
Cited
US3807218A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-08-10 | 1980-02-09 | 1980-08-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-08-10 | 1984-02-09 | 1984-08-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-08-10 | 1988-02-09 | 1988-08-10 | $7700.00 | Window Closed / Lapsed |