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US2456056A
Expired / Lapsed
US
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Mine drill support and driving mechanism
Assignee: DOOLEY BROS
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Filing: 1947-09-10
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Granted: 1948-12-14
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Expires: 1967-09-10
Abstract
No abstract record available.
Inventors
- 👤 Louis J Fellay
- 👤 Harry H Kavanaugh
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 06:48
CPC Classifications
E; E21; E21B; E21B7/00; E21B7/02; E21B7/025; E21B7/022
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1951-12-14 | 1952-06-14 | 1952-12-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1955-12-14 | 1956-06-14 | 1956-12-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1959-12-14 | 1960-06-14 | 1960-12-14 | $7700.00 | Window Closed / Lapsed |