Patent US2294782A successfully refreshed from Google Patents.
US2294782A
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US
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Thermionic valve apparatus
Assignee: AT&T Inc
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Filing: 1941-01-23
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Granted: 1942-09-01
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Expires: 1961-01-23
Abstract
No abstract record available.
Inventors
- 👤 Jacobsen Bent Bulow
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 10:47
CPC Classifications
H; H01; H01J; H01J43/00; H01J43/02; H01J43/025; H03; H03F; H03F1/00; H03F1/34; H03F1/36; H03F3/00; H03F3/02
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) | 1945-08-31 | 1946-03-02 | 1946-09-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1949-08-31 | 1950-03-02 | 1950-09-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1953-08-31 | 1954-03-02 | 1954-09-01 | $7700.00 | Window Closed / Lapsed |