Patent US2489136A successfully refreshed from Google Patents.
US2489136A
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Viscosity regulator
Assignee: A-B Aerotransport
•
Filing: 1943-01-11
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Granted: 1949-11-22
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Expires: 1963-01-11
Abstract
No abstract record available.
Inventors
- 👤 Bo N Hoffstrom
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 07:42
CPC Classifications
G; G01; G01N; G01N11/00; G01N11/02; G01N11/04; G01N11/08; Y; Y10; Y10T; Y10T137/00; Y10T137/2496; Y10T137/2499; Y10T137/2501; Y10T137/6416; Y10T137/6579; Y10T137/7722; Y10T137/7781; Y10T137/7784; Y10T137/7787; Y10T137/7788
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
GB257352A
Cited
GB241652A
Cited
FR615029A
Cited
US2194605A
Cited
US1975937A
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US2028186A
Cited
US2028187A
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US2042860A
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US2140735A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1952-11-21 | 1953-05-23 | 1953-11-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1956-11-21 | 1957-05-23 | 1957-11-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1960-11-21 | 1961-05-23 | 1961-11-22 | $7700.00 | Window Closed / Lapsed |