Patent US3934058A successfully refreshed from Google Patents.
US3934058A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of stabilizing the hot resistance of ceramic positive temperature coefficient resistors
Assignee: Siemens AG
•
Filing: 1974-06-13
•
Granted: 1976-01-20
•
Expires: 1994-06-13
Abstract
Abstract The hot resistance of ceramic positive temperature coefficient resistors is stabilized by subjecting such resistors to a heat treatment over a period of time ranging from 1 to 40 hours at a temperature in the range of 400° to 500° C., either during or after the application of contact coatings on the resistor.
Inventors
- 👤 Baerbel Seebacher
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 10:59
CPC Classifications
H; H01; H01C; H01C17/00; H01C17/30; H01C17/28; H01C17/281; H01C17/283; H01C17/286; H01R; H01R4/00; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49002; Y10T29/49082; Y10T29/49083; Y10T29/49085; Y10T29/49101
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
110 words
A method of stabilizing the hot resistance of a ceramic positive temperature coefficient resistor consisting of a barium titanate based ferroelectric material having a Perowskite structure which is doped so as to render in semiconductive, said resistor being provided with non-blocking contact coatings comprised predominantly of silver applied on a thin film of an indium material selected from the group consisting of indium and indium-gallium comprising: subjecting said positive temperature coefficient resistor to a heat-treatment over a period of time ranging from 1 to 40 hours at a temperature in the range of 400° to 500° C., said heat-treatment occurring at least after the application of said non-blocking contact coatings.
Claim 2
Independent Claim
110 words
A method of stabilizing the hot resistance of a ceramic positive temperature coefficient resistor consisting of a barium titanate based ferroelectric material having a Perowskite structure which is doped so as to render in semiconductive, said resistor being provided with non-blocking contact coatings comprised predominantly of silver applied on a thin film of an indium material selected from the group consisting of indium and indium-gallium comprising: subjecting said positive temperature coefficient resistor to a heat-treatment over a period of time ranging from 1 to 40 hours at a temperature in the range of 400° to 500° C., said heat-treatment occurring at least after the application of said non-blocking contact coatings.
Claim 3
Dependent Claim
50 words
A method as defined in claim 1, wherein said positive temperature coefficient resistor is subjected to a heat-treatment over a period of time ranging from 10 to 20 hours at a temperature in the range of 400° to 500° C. after application of the non-blocking contact coatings to said resistor.
Claim 4
Dependent Claim
53 words
A method as defined in claim 1, wherein said positive temperature coefficient resistor is subjected to a heat-treatment over a period of time ranging from 2 to 4 hours at a temperature in the range of 400° to 500° C. substantially simultaneously with the application of the non-blocking contact coatings to said resistor.
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) | 1979-01-19 | 1979-07-21 | 1980-01-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-01-19 | 1983-07-21 | 1984-01-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-01-19 | 1987-07-21 | 1988-01-20 | $7700.00 | Window Closed / Lapsed |