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US2423631A
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Conversion apparatus
Assignee: University of Minnesota Twin Cities
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Filing: 1942-01-26
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Granted: 1947-07-08
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Expires: 1962-01-26
Abstract
No abstract record available.
Inventors
- 👤 John D Akerman
- 👤 Jean F Piccard
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 11:11
CPC Classifications
F; F17; F17C; F17C9/00; F17C9/02; Y; Y10; Y10T; Y10T137/00; Y10T137/6416; Y10T137/6525
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1493183A
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US1459158A
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US1544854A
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US1510373A
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US1752167A
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FR708002A
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US1831644A
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US2107797A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1950-07-07 | 1951-01-06 | 1951-07-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1954-07-07 | 1955-01-06 | 1955-07-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1958-07-07 | 1959-01-06 | 1959-07-08 | $7700.00 | Window Closed / Lapsed |