Patent US2639404A successfully refreshed from Google Patents.
US2639404A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Magnetron circuit
Assignee: United States, WAR, Secretary of
•
Filing: 1945-04-03
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Granted: 1953-05-19
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Expires: 1965-04-03
Abstract
No abstract record available.
Inventors
- 👤 Everhart Edgar
- 👤 Melvin A Herlin
- 👤 Alexander G Smith
- 👤 William V Smith
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 20:23
CPC Classifications
H; H01; H01J; H01J25/00; H01J25/50; H01J25/52; H01J25/58; H01J25/587
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2217745A
Cited
US2200023A
Cited
US2270777A
Cited
US2241976A
Cited
US2481151A
Cited
US2474938A
Cited
US2466922A
Cited
US2493091A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1956-05-18 | 1956-11-17 | 1957-05-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1960-05-18 | 1960-11-17 | 1961-05-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1964-05-18 | 1964-11-17 | 1965-05-19 | $7700.00 | Window Closed / Lapsed |