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US2491693A
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Propulsion system
Assignee: Individual
•
Filing: 1944-10-19
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Granted: 1949-12-20
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Expires: 1964-10-19
Abstract
No abstract record available.
Inventors
- 👤 Sivertsen Jens
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 20:09
CPC Classifications
B; B64; B64C; B64C11/00
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
FR408033A
Cited
US1942674A
Cited
GB191020813A
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US1133660A
Cited
US1084192A
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US1231871A
Cited
GB177225A
Cited
US1519444A
Cited
US2011061A
Cited
US2229500A
Cited
US2283068A
Cited
US2359536A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1952-12-19 | 1953-06-20 | 1953-12-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1956-12-19 | 1957-06-20 | 1957-12-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1960-12-19 | 1961-06-20 | 1961-12-20 | $7700.00 | Window Closed / Lapsed |