Patent US2720890A successfully refreshed from Google Patents.
US2720890A
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Control of vacuum in internal combustion engine
Assignee: Individual
•
Filing: 1949-06-07
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Granted: 1955-10-18
•
Expires: 1969-06-07
Abstract
No abstract record available.
Inventors
- 👤 Francis H Stroud
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 23:15
CPC Classifications
F; F02; F02M; F02M21/00; F02M2700/00; F02M2700/13; F02M2700/1305; Y; Y10; Y10S; Y10S261/00; Y10S261/19; Y10S55/00; Y10S55/19; Y10T; Y10T137/00; Y10T137/7722; Y10T137/7748; Y10T137/7749; Y10T137/7837; Y10T137/7904; Y10T137/7922; Y10T137/7929; Y10T137/794; Y10T137/7976
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1303817A
Cited
US1120118A
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US1146931A
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US1199152A
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US1228157A
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US1302844A
Cited
US1421135A
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US2581478A
Cited
US2616445A
Cited
US2588493A
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US2601563A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1958-10-17 | 1959-04-18 | 1959-10-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1962-10-17 | 1963-04-18 | 1963-10-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1966-10-17 | 1967-04-18 | 1967-10-18 | $7700.00 | Window Closed / Lapsed |