US2775429A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Drawworks having selective transmission and control
Assignee: EMSCO Manufacturing Co
•
Filing: 1951-03-26
•
Granted: 1956-12-25
•
Expires: 1971-03-26
Abstract
No abstract record available.
Inventors
- 👤 Albert A Ashton
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 13:46
CPC Classifications
E; E21; E21B; E21B3/00; E21B3/02; E21B3/04; E21B3/06; Y; Y10; Y10S; Y10S74/00; Y10S74/02
Claims Analysis
Total Claims: 0
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1959-12-25 | 1960-06-25 | 1960-12-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1963-12-25 | 1964-06-25 | 1964-12-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1967-12-25 | 1968-06-25 | 1968-12-25 | $7700.00 | Window Closed / Lapsed |