Patent US3539896A successfully refreshed from Google Patents.
US3539896A
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Servomechanism including a feed rate comparator for a frequency signal proportional to system error with a programmed frequency
Assignee: Pratt and Whitney Co Inc
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Filing: 1967-04-17
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Granted: 1970-11-10
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Expires: 1987-04-17
Abstract
No abstract record available.
Inventors
- 👤 Johann F Reuteler
- 👤 Robert F Anderson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 22:01
CPC Classifications
G; G05; G05B; G05B19/00; G05B19/02; G05B19/18; G05B19/19; G05B19/21; G05B19/25; G05B19/251; G05B19/253; G05B2219/00; G05B2219/30; G05B2219/43; G05B2219/43157; G05B2219/43179
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US3344260A
Cited
US2927735A
Cited
US3109974A
Cited
US3286085A
Cited
US3349229A
Cited
US3418547A
Cited
US3435314A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1973-11-09 | 1974-05-11 | 1974-11-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1977-11-09 | 1978-05-11 | 1978-11-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1981-11-09 | 1982-05-11 | 1982-11-10 | $7700.00 | Window Closed / Lapsed |