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Patent US2554843A successfully refreshed from Google Patents.
US2554843A
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Proportional pressure doubleacting power amplifier
Assignee: OLIVE BERTHA STAUDE
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Filing: 1945-07-31
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Granted: 1951-05-29
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Expires: 1965-07-31
Abstract
No abstract record available.
Inventors
- 👤 Edwin G Staude
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 10:35
CPC Classifications
F; F15; F15B; F15B9/00; F15B9/14
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2400418A
Cited
US754277A
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US860461A
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GB190819980A
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US1890041A
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US2095841A
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US2398421A
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US2382866A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1954-05-28 | 1954-11-27 | 1955-05-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-05-28 | 1958-11-27 | 1959-05-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-05-28 | 1962-11-27 | 1963-05-29 | $7700.00 | Window Closed / Lapsed |