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US2621004A
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Retractable landing gear
Assignee: Electrol Inc
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Filing: 1950-06-16
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Granted: 1952-12-09
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Expires: 1970-06-16
Abstract
No abstract record available.
Inventors
- 👤 Benjamin N Ashton
- 👤 Edmund D Holland
- 👤 Roy A Wulff
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 09:33
CPC Classifications
B; B64; B64C; B64C25/00; B64C25/02; B64C25/08; B64C25/10; B64C25/12
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2390661A
Cited
US2478426A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1955-12-09 | 1956-06-09 | 1956-12-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1959-12-09 | 1960-06-09 | 1960-12-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1963-12-09 | 1964-06-09 | 1964-12-09 | $7700.00 | Window Closed / Lapsed |