US2798692A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Tunneling apparatus
Assignee: Individual
•
Filing: 1955-04-08
•
Granted: 1957-07-09
•
Expires: 1975-04-08
Abstract
No abstract record available.
Inventors
- 👤 Raymond R Thomas
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 07:48
CPC Classifications
E; E21; E21B; E21B7/00; E21B7/04; E21B7/046; Y; Y10; Y10T; Y10T74/00; Y10T74/18; Y10T74/18056; Y10T74/18184; Y10T74/182
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
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) | 1960-07-08 | 1961-01-07 | 1961-07-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1964-07-08 | 1965-01-07 | 1965-07-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1968-07-08 | 1969-01-07 | 1969-07-09 | $7700.00 | Window Closed / Lapsed |