US2721444A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Series-type multiple ram jet propulsion system
Assignee: Individual
•
Filing: 1948-09-21
•
Granted: 1955-10-25
•
Expires: 1968-09-21
Abstract
No abstract record available.
Inventors
- 👤 Johnson Horace James
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 19:28
CPC Classifications
F; F02; F02K; F02K7/00; F02K7/10
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1375601A
Cited
US1405482A
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US1369672A
Cited
FR522163A
Cited
GB439805A
Cited
DE648878C
Cited
US2547936A
Cited
US2574460A
Cited
US2670597A
Cited
US2520388A
Cited
US2589945A
Cited
US2543758A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1958-10-24 | 1959-04-25 | 1959-10-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1962-10-24 | 1963-04-25 | 1963-10-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1966-10-24 | 1967-04-25 | 1967-10-25 | $7700.00 | Window Closed / Lapsed |