US2635994A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Production of carbon resistors
Assignee: Sprague Electric Co
•
Filing: 1950-04-27
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Granted: 1953-04-21
•
Expires: 1970-04-27
Abstract
No abstract record available.
Inventors
- 👤 Tierman Melvin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 22:04
CPC Classifications
H; H01; H01B; H01B1/00; H01B1/20; H01B1/24
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
94 words
A PROCESS FOR PRODUCING A STABLE CARBON TYPE OF RESISTOR HAVING UNIFORM OHMIC VALUES AND PREDICTABLE TEMPERATURE COEFFICIENTS OF RESISTANCE ON A NON-CONDUCTIVE SOLID BASE MATERIAL WHICH IS INERT TO TEMPERATURES AT LEAST AS HIGH AS 150* C., WHICH COMPRISES, PREHEATING SAID BASE TO A TEMPERATURE OF AT LEAST 150* C. IN AN OXIDIZING ATMOSPHERE TO REMOVE EXTRANEOUS SURFACE MATTER BY OXIDIZATION, EXPOSING SAID PREHEATED BASE TO A CARBON ARC IN A CARBON ARC CHAMBER HAVING AN INERT ATMOSPHERE TO CAUSE A THIN RESISTANCE LAYER OF PURE CARBON TO DEPOSIT UPON SAID BASE, THE
Claim 2
Dependent Claim
94 words
A PROCESS FOR PRODUCING A STABLE CARBON TYPE OF RESISTOR HAVING UNIFORM OHMIC VALUES AND PREDICTABLE TEMPERATURE COEFFICIENTS OF RESISTANCE ON A NON-CONDUCTIVE SOLID BASE MATERIAL WHICH IS INERT TO TEMPERATURES AT LEAST AS HIGH AS 150* C., WHICH COMPRISES, PREHEATING SAID BASE TO A TEMPERATURE OF AT LEAST 150* C. IN AN OXIDIZING ATMOSPHERE TO REMOVE EXTRANEOUS SURFACE MATTER BY OXIDIZATION, EXPOSING SAID PREHEATED BASE TO A CARBON ARC IN A CARBON ARC CHAMBER HAVING AN INERT ATMOSPHERE TO CAUSE A THIN RESISTANCE LAYER OF PURE CARBON TO DEPOSIT UPON SAID BASE, THE
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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) | 1956-04-20 | 1956-10-20 | 1957-04-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1960-04-20 | 1960-10-20 | 1961-04-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1964-04-20 | 1964-10-20 | 1965-04-21 | $7700.00 | Window Closed / Lapsed |