US2521385A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Core-cutting machine
Assignee: Keystone Engineering Co
•
Filing: 1946-06-28
•
Granted: 1950-09-05
•
Expires: 1966-06-28
Abstract
No abstract record available.
Inventors
- 👤 Alexander G Marion
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 05:52
CPC Classifications
B; B26; B26D; B26D3/00; B26D3/16; Y; Y10; Y10S; Y10S29/00; Y10S29/059; Y10T; Y10T82/00; Y10T82/16; Y10T82/16426; Y10T82/16803; Y10T82/16819; Y10T82/16868; Y10T82/16951; Y10T82/16967
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1546564A
Cited
US1573613A
Cited
US1892058A
Cited
US2181124A
Cited
US2206262A
Cited
US2398929A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1953-09-04 | 1954-03-06 | 1954-09-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1957-09-04 | 1958-03-06 | 1958-09-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1961-09-04 | 1962-03-06 | 1962-09-05 | $7700.00 | Window Closed / Lapsed |