US2823901A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Expansible rotary drilling tools
Assignee: Individual
•
Filing: 1955-11-07
•
Granted: 1958-02-18
•
Expires: 1975-11-07
Abstract
No abstract record available.
Inventors
- 👤 Archer W Kammerer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 01:42
CPC Classifications
E; E21; E21B; E21B29/00; E21B29/002; E21B29/005; E21B10/00; E21B10/26; E21B10/32; E21B10/322
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) | 1961-02-17 | 1961-08-19 | 1962-02-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-02-17 | 1965-08-19 | 1966-02-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-02-17 | 1969-08-19 | 1970-02-18 | $7700.00 | Window Closed / Lapsed |