Patent US3530681A successfully refreshed from Google Patents.
US3530681A
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US
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Hydraulically driven cryogenic refrigerator
Assignee: Raytheon Co
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Filing: 1968-08-05
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Granted: 1970-09-29
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Expires: 1988-08-05
Abstract
No abstract record available.
Inventors
- 👤 Axel G Dehne
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 09:50
CPC Classifications
F; F25; F25B; F25B9/00; F25B9/14; F25B31/00; F25B2309/00; F25B2309/003
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US321085A
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US393461A
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US2274224A
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US2746241A
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US2698517A
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US3045436A
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US3091092A
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US3119237A
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US3188821A
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US3367121A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1973-09-28 | 1974-03-30 | 1974-09-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1977-09-28 | 1978-03-30 | 1978-09-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1981-09-28 | 1982-03-30 | 1982-09-29 | $7700.00 | Window Closed / Lapsed |