Patent US3389561A successfully refreshed from Google Patents.
US3389561A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of and apparatus for providing anchors in earth and/or rock formations
Assignee: English Electric Co Ltd
•
Filing: 1966-05-23
•
Granted: 1968-06-25
•
Expires: 1986-05-23
Abstract
No abstract record available.
Inventors
- 👤 Taylor Kenneth Ray
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 13:10
CPC Classifications
E; E21; E21D; E21D21/00; E21D21/002; E21D20/00; E21D20/02; E21D20/021
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
US1746848A
Cited
US2162130A
Cited
US2667037A
Cited
US2618192A
Cited
GB820945A
Cited
US2970444A
Cited
US3212582A
Cited
US3234723A
Cited
FR1249759A
Cited
US3172947A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1971-06-25 | 1971-12-25 | 1972-06-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1975-06-25 | 1975-12-25 | 1976-06-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1979-06-25 | 1979-12-25 | 1980-06-25 | $7700.00 | Window Closed / Lapsed |