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Patent US1972162A successfully refreshed from Google Patents.
US1972162A
Expired / Lapsed
US
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Heater element electron emitting cathode
Assignee: Westinghouse Lamp Co
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Filing: 1930-01-28
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Granted: 1934-09-04
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Expires: 1950-01-28
Abstract
No abstract record available.
Inventors
- 👤 Warley L Parrott
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 05:56
CPC Classifications
H; H01; H01J; H01J1/00; H01J1/02; H01J1/13; H01J1/20; H01J1/22; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49002; Y10T29/49082; Y10T29/49087; Y10T29/49096
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1937-09-03 | 1938-03-05 | 1938-09-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1941-09-03 | 1942-03-05 | 1942-09-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1945-09-03 | 1946-03-05 | 1946-09-04 | $7700.00 | Window Closed / Lapsed |