US2712435A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Shock absorber for rotary drills
Assignee: Individual
•
Filing: 1951-03-15
•
Granted: 1955-07-05
•
Expires: 1971-03-15
Abstract
No abstract record available.
Inventors
- 👤 Walter T Allen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 06:01
CPC Classifications
E; E21; E21B; E21B17/00; E21B17/02; E21B17/04; E21B17/07
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
US1785559A
Cited
US1902421A
Cited
US2023527A
Cited
US2240519A
Cited
US2263770A
Cited
US2325132A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1958-07-04 | 1959-01-03 | 1959-07-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1962-07-04 | 1963-01-03 | 1963-07-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1966-07-04 | 1967-01-03 | 1967-07-05 | $7700.00 | Window Closed / Lapsed |