Patent US2689681A successfully refreshed from Google Patents.
US2689681A
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US
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Reversely rotating screw type multiple impeller compressor
Assignee: RTX Corp
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Filing: 1949-09-17
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Granted: 1954-09-21
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Expires: 1969-09-17
Abstract
No abstract record available.
Inventors
- 👤 Sabatiuk Andrew
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 19:54
CPC Classifications
F; F04; F04D; F04D21/00; F04D19/00; F04D19/02; F04D19/024
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2243467A
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US2430398A
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US2461931A
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US2426270A
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US2435236A
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GB588096A
Cited
US2384000A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1957-09-20 | 1958-03-22 | 1958-09-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1961-09-20 | 1962-03-22 | 1962-09-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1965-09-20 | 1966-03-22 | 1966-09-21 | $7700.00 | Window Closed / Lapsed |