Patent US1987971A successfully refreshed from Google Patents.
Patent US1401040A successfully refreshed from Google Patents.
US1401040A
Expired / Lapsed
US
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Safety spring-sling particularly adapted for use with parachutes
Assignee: E R CALTHROP S AERIAL PATENTS
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Filing: 1918-07-31
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Granted: 1921-12-20
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Expires: 1938-07-31
Abstract
No abstract record available.
Inventors
- 👤 Calthrop Everard Richard
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 04:24
CPC Classifications
B; B64; B64D; B64D17/00; B64D17/22; B64D17/36; Y; Y10; Y10T; Y10T24/00; Y10T24/39; Y10T24/3916; Y10T24/3929
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1924-12-19 | 1925-06-20 | 1925-12-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1928-12-19 | 1929-06-20 | 1929-12-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1932-12-19 | 1933-06-20 | 1933-12-20 | $7700.00 | Window Closed / Lapsed |