Patent US2431721A successfully refreshed from Google Patents.
US2431721A
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Temperature and liquid level control for refrigeration apparatus
Assignee: Westinghouse Electric Corp
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Filing: 1945-11-21
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Granted: 1947-12-02
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Expires: 1965-11-21
Abstract
No abstract record available.
Inventors
- 👤 Woodrow W Wiseman
- 👤 Gordon K Terry
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 16:32
CPC Classifications
G; G05; G05D; G05D9/00; G05D9/02; F; F25; F25D; F25D31/00; F25D31/002; F25D31/003; Y; Y10; Y10T; Y10T137/00; Y10T137/7287; Y10T137/7297; Y10T137/7329; Y10T137/7358; Y10T137/7407; Y10T137/8593; Y10T137/87917
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2346259A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1950-12-01 | 1951-06-02 | 1951-12-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1954-12-01 | 1955-06-02 | 1955-12-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1958-12-01 | 1959-06-02 | 1959-12-02 | $7700.00 | Window Closed / Lapsed |