US2497040A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Helicopter construction
Assignee: Individual
•
Filing: 1947-04-19
•
Granted: 1950-02-07
•
Expires: 1967-04-19
Abstract
No abstract record available.
Inventors
- 👤 Samuel B Williams
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 08:09
CPC Classifications
B; B64; B64C; B64C27/00; B64C27/04; B64C27/08; B64C27/10
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1330321A
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DE285012C
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US871729A
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US1371493A
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US1550106A
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US1388642A
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US1546313A
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US1464410A
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US1485704A
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US1793651A
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US1923842A
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US2108839A
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US2074807A
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US2312624A
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US2295503A
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US2464285A
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1953-02-06 | 1953-08-08 | 1954-02-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1957-02-06 | 1957-08-08 | 1958-02-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1961-02-06 | 1961-08-08 | 1962-02-07 | $7700.00 | Window Closed / Lapsed |