Patent US2604621A successfully refreshed from Google Patents.
US2604621A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Radio system for aircraft guidance
Assignee: International Standard Electric Corp
•
Filing: 1943-08-11
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Granted: 1952-07-22
•
Expires: 1963-08-11
Abstract
No abstract record available.
Inventors
- 👤 Earp Charles William
- 👤 Strong Charles Eric
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 16:36
CPC Classifications
G; G01; G01S; G01S13/00; G01S13/88; G01S13/91; G01S13/913; G01S1/00; G01S1/02; G01S13/02; G01S13/06; G01S13/08; G01S13/32; G01S13/34; G01S13/343
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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US2225046A
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US2423644A
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US2218923A
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US2411520A
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US2248215A
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US2301929A
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US2307316A
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US2371979A
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US2412003A
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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) | 1955-07-22 | 1956-01-21 | 1956-07-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1959-07-22 | 1960-01-21 | 1960-07-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1963-07-22 | 1964-01-21 | 1964-07-22 | $7700.00 | Window Closed / Lapsed |