Patent US2881390A successfully refreshed from Google Patents.
US2881390A
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Piezo-electric type frequency changer
Assignee: General Electric Co
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Filing: 1952-04-21
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Granted: 1959-04-07
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Expires: 1972-04-21
Abstract
No abstract record available.
Inventors
- 👤 Oliver H Winn
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 16:21
CPC Classifications
H; H03; H03B; H03B5/00; H03B5/30; H03B5/32; H03B5/34; G; G01; G01S; G01S7/00; G01S7/02; G01S7/04; G01S7/06; G01S7/22
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2262966A
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US2274486A
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GB654684A
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US2573070A
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US2582608A
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US2475625A
Cited
US2469174A
Cited
US2554308A
Cited
US2504852A
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GB653102A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1962-04-06 | 1962-10-06 | 1963-04-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1966-04-06 | 1966-10-06 | 1967-04-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1970-04-06 | 1970-10-06 | 1971-04-07 | $7700.00 | Window Closed / Lapsed |