Patent US2444222A successfully refreshed from Google Patents.
US2444222A
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Oxygen enrichment system for gas engines
Assignee: INVEX Inc
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Filing: 1943-08-18
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Granted: 1948-06-29
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Expires: 1963-08-18
Abstract
No abstract record available.
Inventors
- 👤 Palmer H Craig
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 21:00
CPC Classifications
F; F02; F02M; F02M1/00; F02M25/00; F02M25/10; F02M25/12; F02M69/00; F02M2700/00; F02M2700/43; F02M2700/4302; F02M2700/434; F02M2700/4342; F02M2700/4345; F02M2700/4397; Y; Y02; Y02T; Y02T10/00; Y02T10/10; Y02T10/12; Y10; Y10S; Y10S48/00; Y10S48/05
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2178454A
Cited
US820283A
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US1174631A
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US1232215A
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US1553737A
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US1871226A
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US2147671A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1951-06-29 | 1951-12-29 | 1952-06-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1955-06-29 | 1955-12-29 | 1956-06-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1959-06-29 | 1959-12-29 | 1960-06-29 | $7700.00 | Window Closed / Lapsed |