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US2261153A
Expired / Lapsed
US
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Protective circuits for electron tubes
Assignee: Liebel Flarsheim Co LLC
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Filing: 1941-05-22
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Granted: 1941-11-04
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Expires: 1961-05-22
Abstract
No abstract record available.
Inventors
- 👤 Carl K Gieringer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 03:47
CPC Classifications
A; A61; A61N; A61N5/00
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) | 1944-11-03 | 1945-05-05 | 1945-11-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1948-11-03 | 1949-05-05 | 1949-11-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1952-11-03 | 1953-05-05 | 1953-11-04 | $7700.00 | Window Closed / Lapsed |