Patent EP0743675A1 successfully refreshed from Google Patents.
US2821177A
Expired / Lapsed
US
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Internal combustion engines of the compression ignition type
Assignee: Ricardo PLC
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Filing: 1955-10-07
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Granted: 1958-01-28
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Expires: 1975-10-07
Abstract
No abstract record available.
Inventors
- 👤 Holt George Allen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 17:28
CPC Classifications
F; F02; F02B; F02B19/00; F02B19/14; F02B19/08; F02B23/00; F02B23/02; F02B23/04; Y; Y02; Y02T; Y02T10/00; Y02T10/10; Y02T10/12
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) | 1961-01-27 | 1961-07-29 | 1962-01-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-01-27 | 1965-07-29 | 1966-01-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-01-27 | 1969-07-29 | 1970-01-28 | $7700.00 | Window Closed / Lapsed |