US2546899A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Coal boring head
Assignee: Salem Tool Co
•
Filing: 1948-11-23
•
Granted: 1951-03-27
•
Expires: 1968-11-23
Abstract
No abstract record available.
Inventors
- 👤 Vincent J Mccarthy
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 09:36
CPC Classifications
E; E21; E21B; E21B10/00; E21B10/44; E21B4/00; E21B4/16
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1077620A
Cited
US1645007A
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US1350059A
Cited
US1653111A
Cited
US1812719A
Cited
US1871638A
Cited
US2404605A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1954-03-26 | 1954-09-25 | 1955-03-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-03-26 | 1958-09-25 | 1959-03-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-03-26 | 1962-09-25 | 1963-03-27 | $7700.00 | Window Closed / Lapsed |