US2522029A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Airplane approach control system
Assignee: SPX Technologies Inc
•
Filing: 1945-01-22
•
Granted: 1950-09-12
•
Expires: 1965-01-22
Abstract
No abstract record available.
Inventors
- 👤 Oscar S Field
- 👤 Ralph W Hewes
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 15:47
CPC Classifications
G; G08; G08G; G08G5/00; G08G5/50; G08G5/56; G08G5/54
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2373771A
Cited
US2063534A
Cited
US1999047A
Cited
US2268240A
Cited
US2399671A
Cited
US2344761A
Cited
US2425973A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1953-09-11 | 1954-03-13 | 1954-09-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1957-09-11 | 1958-03-13 | 1958-09-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1961-09-11 | 1962-03-13 | 1962-09-12 | $7700.00 | Window Closed / Lapsed |