US2673452A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus for installing roof suspension bolts in mines
Assignee: HARRY M JOHNSTONE
•
Filing: 1950-04-12
•
Granted: 1954-03-30
•
Expires: 1970-04-12
Abstract
No abstract record available.
Inventors
- 👤 Paul E Glaze
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 21:45
CPC Classifications
E; E21; E21D; E21D20/00; E21D20/003
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
US1218604A
Cited
US1914430A
Cited
US1898369A
Cited
US2208025A
Cited
US2407976A
Cited
US2500931A
Cited
US2500932A
Cited
US2505331A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1957-03-29 | 1957-09-28 | 1958-03-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1961-03-29 | 1961-09-28 | 1962-03-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1965-03-29 | 1965-09-28 | 1966-03-30 | $7700.00 | Window Closed / Lapsed |