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US2808987A
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Apparatus for generating trigonometric functions
Assignee: NORDEN KETAY CORP
•
Filing: 1953-11-30
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Granted: 1957-10-08
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Expires: 1973-11-30
Abstract
No abstract record available.
Inventors
- 👤 Jack B Speller
- 👤 Frank S Preston
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 11:16
CPC Classifications
G; G06; G06G; G06G7/00; G06G7/12; G06G7/22
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2467646A
Cited
US2557811A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1960-10-07 | 1961-04-08 | 1961-10-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1964-10-07 | 1965-04-08 | 1965-10-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1968-10-07 | 1969-04-08 | 1969-10-08 | $7700.00 | Window Closed / Lapsed |