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Patent US2448251A successfully refreshed from Google Patents.
US2448251A
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Liquid level control
Assignee: Individual
•
Filing: 1946-05-15
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Granted: 1948-08-31
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Expires: 1966-05-15
Abstract
No abstract record available.
Inventors
- 👤 Julian A Campbell
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 09:06
CPC Classifications
F; F22; F22D; F22D5/00; F22D5/08; F22D5/10; F22D5/24; Y; Y10; Y10T; Y10T137/00; Y10T137/7287; Y10T137/7358; Y10T137/742; Y10T137/7423
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US382515A
Cited
US384200A
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US841334A
Cited
US1876004A
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US2180802A
Cited
GB473603A
Cited
US2181829A
Cited
US2353641A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1951-08-31 | 1952-03-01 | 1952-08-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1955-08-31 | 1956-03-01 | 1956-08-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1959-08-31 | 1960-03-01 | 1960-08-31 | $7700.00 | Window Closed / Lapsed |