Patent US1644490A successfully refreshed from Google Patents.
US1644490A
Expired / Lapsed
US
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Rotary internal-combustion engine
Assignee: Individual
•
Filing: 1921-01-21
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Granted: 1927-10-04
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Expires: 1941-01-21
Abstract
No abstract record available.
Inventors
- 👤 Post Van Zo
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 11:29
CPC Classifications
F; F01; F01C; F01C1/00; F01C1/30; F01C1/34; F01C1/344; F01C1/3446; F02; F02B; F02B53/00; F02B2730/00; F02B2730/01; F02B2730/012; 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) | 1930-10-03 | 1931-04-04 | 1931-10-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1934-10-03 | 1935-04-04 | 1935-10-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1938-10-03 | 1939-04-04 | 1939-10-04 | $7700.00 | Window Closed / Lapsed |