Patent US2544481A successfully refreshed from Google Patents.
US2544481A
Expired / Lapsed
US
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Rotary displacement device
Assignee: Individual
•
Filing: 1947-04-24
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Granted: 1951-03-06
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Expires: 1967-04-24
Abstract
No abstract record available.
Inventors
- 👤 Bancroft Charles
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 12:03
CPC Classifications
F; F01; F01C; F01C1/00; F01C1/02; F01C1/063; F01C1/07; F02; F02B; F02B53/00
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1843155A
Cited
US1921747A
Cited
US1838252A
Cited
US1997233A
Cited
GB444706A
Cited
US2096074A
Cited
US2243653A
Cited
US2132596A
Cited
US2222706A
Cited
US2270493A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1954-03-05 | 1954-09-04 | 1955-03-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-03-05 | 1958-09-04 | 1959-03-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-03-05 | 1962-09-04 | 1963-03-06 | $7700.00 | Window Closed / Lapsed |