US2520040A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Coal cutting, breaking, and loading mining machine
Assignee: Jeffrey Manufacturing Co
•
Filing: 1947-03-19
•
Granted: 1950-08-22
•
Expires: 1967-03-19
Abstract
No abstract record available.
Inventors
- 👤 Nils D Levin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 15:48
CPC Classifications
E; E21; E21C; E21C27/00; E21C27/10; E21C27/12; E21C27/124
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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US2281503A
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US2257181A
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US2329875A
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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) | 1953-08-21 | 1954-02-20 | 1954-08-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1957-08-21 | 1958-02-20 | 1958-08-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1961-08-21 | 1962-02-20 | 1962-08-22 | $7700.00 | Window Closed / Lapsed |