Patent US2801523A successfully refreshed from Google Patents.
US2801523A
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US
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Defrosting apparatus for refrigeration systems
Assignee: Individual
•
Filing: 1952-05-15
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Granted: 1957-08-06
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Expires: 1972-05-15
Abstract
No abstract record available.
Inventors
- 👤 Charles C Hansen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 20:23
CPC Classifications
F; F25; F25B; F25B47/00; F25B47/02; F25B47/022; F25B31/00; F25B31/002; F25B31/004
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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US2555161A
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US2530440A
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US2635433A
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US2658358A
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US2637983A
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US2641908A
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US2564310A
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US2678545A
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US2645101A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1960-08-05 | 1961-02-04 | 1961-08-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1964-08-05 | 1965-02-04 | 1965-08-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1968-08-05 | 1969-02-04 | 1969-08-06 | $7700.00 | Window Closed / Lapsed |