Patent US2680346A successfully refreshed from Google Patents.
US2680346A
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Jet engine inlet duct coupling
Assignee: Northrop Grumman Corp
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Filing: 1951-09-10
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Granted: 1954-06-08
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Expires: 1971-09-10
Abstract
No abstract record available.
Inventors
- 👤 Harold E Michael
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 22:57
CPC Classifications
F; F16; F16L; F16L51/00; F16L51/02; F16L51/022; F16L51/024; B; B64; B64D; B64D27/00; B64D27/40; B64D27/402
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1541601A
Cited
CH191911A
Cited
US2352038A
Cited
US2437385A
Cited
GB579416A
Cited
US2494659A
Cited
US2564042A
Cited
US2587345A
Cited
US2493641A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1957-06-07 | 1957-12-07 | 1958-06-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1961-06-07 | 1961-12-07 | 1962-06-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1965-06-07 | 1965-12-07 | 1966-06-08 | $7700.00 | Window Closed / Lapsed |