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Patent US2581438A successfully refreshed from Google Patents.
US2581438A
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Navigation computer and piloting system
Assignee: Unisys Corp
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Filing: 1946-03-30
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Granted: 1952-01-08
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Expires: 1966-03-30
Abstract
No abstract record available.
Inventors
- 👤 Palmer Winslow
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 13:23
CPC Classifications
G; G06; G06G; G06G7/00; G06G7/48; G06G7/78; G01; G01S; G01S1/00; G01S1/02; G06G7/12; G06G7/22
Claims Analysis
Total Claims: 0
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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) | 1955-01-07 | 1955-07-09 | 1956-01-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1959-01-07 | 1959-07-09 | 1960-01-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1963-01-07 | 1963-07-09 | 1964-01-08 | $7700.00 | Window Closed / Lapsed |