US2521684A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Rotary wing aircraft
Assignee: Unisys Corp
•
Filing: 1944-08-10
•
Granted: 1950-09-12
•
Expires: 1964-08-10
Abstract
No abstract record available.
Inventors
- 👤 Mortimer F Bates
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 19:08
CPC Classifications
B; B64; B64C; B64C27/00; B64C27/20
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1133660A
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US1819075A
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US1919089A
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US1868392A
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US1915855A
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US1985819A
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US2115754A
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US2085359A
Cited
US2209879A
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US2382460A
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US2328786A
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US2350129A
Cited
US2428794A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1953-09-11 | 1954-03-13 | 1954-09-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1957-09-11 | 1958-03-13 | 1958-09-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1961-09-11 | 1962-03-13 | 1962-09-12 | $7700.00 | Window Closed / Lapsed |