US1591717A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electron emission material and method of manufacture
Assignee: Westinghouse Lamp Co
•
Filing: 1922-09-28
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Granted: 1926-07-06
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Expires: 1942-09-28
Abstract
No abstract record available.
Inventors
- 👤 Marden John Wesley
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 20:45
CPC Classifications
H; H01; H01J; H01J1/00; H01J1/02; H01J1/13; H01J1/14; Y; Y10; Y10T; Y10T428/00; Y10T428/12; Y10T428/12014; Y10T428/12028; Y10T428/12063; Y10T428/12104; Y10T428/12111
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) | 1929-07-05 | 1930-01-04 | 1930-07-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1933-07-05 | 1934-01-04 | 1934-07-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1937-07-05 | 1938-01-04 | 1938-07-06 | $7700.00 | Window Closed / Lapsed |