US2489220A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Light-sensitive altitude and direction indicator
Assignee: LAFAYETTE M HUGHES
•
Filing: 1945-03-15
•
Granted: 1949-11-22
•
Expires: 1965-03-15
Abstract
No abstract record available.
Inventors
- 👤 Robert J Herbold
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 19:44
CPC Classifications
G; G01; G01S; G01S1/00; G01S1/02
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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US2415178A
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1952-11-21 | 1953-05-23 | 1953-11-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1956-11-21 | 1957-05-23 | 1957-11-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1960-11-21 | 1961-05-23 | 1961-11-22 | $7700.00 | Window Closed / Lapsed |