US2731237A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Combination earth auger with rock drilling point
Assignee: Individual
•
Filing: 1951-11-28
•
Granted: 1956-01-17
•
Expires: 1971-11-28
Abstract
No abstract record available.
Inventors
- 👤 Frederick E Henning
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 20:29
CPC Classifications
E; E21; E21B; E21B10/00; E21B10/44
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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US187705A
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US2575975A
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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) | 1959-01-16 | 1959-07-18 | 1960-01-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1963-01-16 | 1963-07-18 | 1964-01-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1967-01-16 | 1967-07-18 | 1968-01-17 | $7700.00 | Window Closed / Lapsed |