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US2539411A
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Automatic pilot
Assignee: Unisys Corp
•
Filing: 1944-02-03
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Granted: 1951-01-30
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Expires: 1964-02-03
Abstract
No abstract record available.
Inventors
- 👤 Orland E Esval
- 👤 Carl A Frische
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 10:22
CPC Classifications
G; G05; G05D; G05D1/00; G05D1/02; G05D1/0202; G01; G01C; G01C19/00; Y; Y10; Y10T; Y10T74/00; Y10T74/18; Y10T74/18056; Y10T74/18288
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1863415A
Cited
US1958259A
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US2115498A
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US2126855A
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US2177242A
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US2308566A
Cited
US2313682A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1954-01-29 | 1954-07-31 | 1955-01-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-01-29 | 1958-07-31 | 1959-01-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-01-29 | 1962-07-31 | 1963-01-30 | $7700.00 | Window Closed / Lapsed |