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US3423948A
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US
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Cryogenic refrigerator adapted to miniaturization
Assignee: Raytheon Co
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Filing: 1967-04-03
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Granted: 1969-01-28
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Expires: 1987-04-03
Abstract
No abstract record available.
Inventors
- 👤 Kenneth W Cowans
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 10:30
CPC Classifications
F; F02; F02G; F02G1/00; F02G1/04; F02G1/043; F02G1/044; F02G1/0445
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1972-01-28 | 1972-07-29 | 1973-01-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1976-01-28 | 1976-07-29 | 1977-01-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1980-01-28 | 1980-07-29 | 1981-01-28 | $7700.00 | Window Closed / Lapsed |