US2841889A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Projectable slide rule
Assignee: Individual
•
Filing: 1955-04-04
•
Granted: 1958-07-08
•
Expires: 1975-04-04
Abstract
No abstract record available.
Inventors
- 👤 Thomas C Coale
- 👤 Wesley F Heyman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 12:15
CPC Classifications
G; G09; G09B; G09B23/00; G09B23/02; G06; G06G; G06G1/00; G06G1/02
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US535375A
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US1554931A
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US1431409A
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US1579880A
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US1875927A
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US2073421A
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FR817011A
Cited
US2173459A
Cited
GB627514A
Cited
GB719080A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1961-07-07 | 1962-01-06 | 1962-07-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-07-07 | 1966-01-06 | 1966-07-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-07-07 | 1970-01-06 | 1970-07-08 | $7700.00 | Window Closed / Lapsed |