US1894059A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for producing electron emitters and the product
Assignee: DE FOREST RADIO Co
•
Filing: 1927-04-08
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Granted: 1933-01-10
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Expires: 1947-04-08
Abstract
No abstract record available.
Inventors
- 👤 Ruffley Frederick
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 22:03
CPC Classifications
H; H01; H01J; H01J9/00; H01J9/02; H01J9/04; H01J9/042; Y; Y10; Y10T; Y10T428/00; Y10T428/29; Y10T428/2913; Y10T428/2933; Y10T428/294; Y10T428/2958
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) | 1936-01-10 | 1936-07-11 | 1937-01-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1940-01-10 | 1940-07-11 | 1941-01-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1944-01-10 | 1944-07-11 | 1945-01-10 | $7700.00 | Window Closed / Lapsed |