Patent US2557607A successfully refreshed from Google Patents.
US2557607A
Expired / Lapsed
US
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Hot gas engine with finned cylinder head
Assignee: Shell Development Co
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Filing: 1949-03-29
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Granted: 1951-06-19
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Expires: 1969-03-29
Abstract
No abstract record available.
Inventors
- 👤 Lubbock Isaac
- 👤 Tipler William
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 09:04
CPC Classifications
F; F02; F02G; F02G1/00; F02G1/04; F02G1/043; F02G1/053; F02G1/055; F02G2254/00; F02G2254/10; F02G2254/50; F02G2255/00; F02G2255/10
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) | 1954-06-18 | 1954-12-18 | 1955-06-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-06-18 | 1958-12-18 | 1959-06-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-06-18 | 1962-12-18 | 1963-06-19 | $7700.00 | Window Closed / Lapsed |