US2621022A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of drilling overburden, unconsolidated rock formation or placer ground with low-temperature freezing fluids
Assignee: Individual
•
Filing: 1945-02-09
•
Granted: 1952-12-09
•
Expires: 1965-02-09
Abstract
No abstract record available.
Inventors
- 👤 John D Bardill
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 22:00
CPC Classifications
E; E21; E21D; E21D1/00; E21D1/10; E21D1/12; E21B; E21B33/00; E21B33/10; E21B36/00; E21B36/001; Y; Y10; Y10T; Y10T24/00; Y10T24/39; Y10T24/3902
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
US1974145A
Cited
US2099825A
Cited
US2193219A
Cited
US2223027A
Cited
US2241273A
Cited
US2297660A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1955-12-09 | 1956-06-09 | 1956-12-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1959-12-09 | 1960-06-09 | 1960-12-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1963-12-09 | 1964-06-09 | 1964-12-09 | $7700.00 | Window Closed / Lapsed |