Patent US2144561A successfully refreshed from Google Patents.
US2144561A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Four stroke cycle internal combustion engine
Assignee: Individual
•
Filing: 1936-01-29
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Granted: 1939-01-17
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Expires: 1956-01-29
Abstract
No abstract record available.
Inventors
- 👤 Bucht Alfred
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 20:55
CPC Classifications
F; F02; F02B; F02B31/00; F02B19/00; F02B19/02; F02B19/04; F02B3/00; F02B3/06; Y; Y02; Y02T; Y02T10/00; Y02T10/10; Y02T10/12
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1942-01-16 | 1942-07-18 | 1943-01-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1946-01-16 | 1946-07-18 | 1947-01-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1950-01-16 | 1950-07-18 | 1951-01-17 | $7700.00 | Window Closed / Lapsed |