US2878709A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Mine roof bolts having segmented shell biased outwardly by resilient washer
Assignee: Republic Steel Corp
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Filing: 1956-05-14
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Granted: 1959-03-24
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Expires: 1976-05-14
Abstract
No abstract record available.
Inventors
- 👤 Horvath Joseph
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 19:00
CPC Classifications
E; E21; E21D; E21D21/00; E21D21/008
Claims Analysis
Total Claims: 0
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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) | 1962-03-23 | 1962-09-22 | 1963-03-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1966-03-23 | 1966-09-22 | 1967-03-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1970-03-23 | 1970-09-22 | 1971-03-24 | $7700.00 | Window Closed / Lapsed |