Patent US2621640A successfully refreshed from Google Patents.
US2621640A
Expired / Lapsed
US
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Hydraulic valve-operating system operable to vary valve lift and timing
Assignee: Individual
•
Filing: 1943-01-20
•
Granted: 1952-12-16
•
Expires: 1963-01-20
Abstract
No abstract record available.
Inventors
- 👤 Reggio Ferdinando Carlo
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 19:21
CPC Classifications
F; F01; F01L; F01L9/00; F01L9/10; F01L9/11; F01L1/00; F01L1/34; F01L1/344; F01L1/3442; F01L2001/34423; F01L2001/34446
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) | 1955-12-16 | 1956-06-16 | 1956-12-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1959-12-16 | 1960-06-16 | 1960-12-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1963-12-16 | 1964-06-16 | 1964-12-16 | $7700.00 | Window Closed / Lapsed |