US2421245A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Heat exchange element
Assignee: Cherry Burrell Corp
•
Filing: 1942-05-13
•
Granted: 1947-05-27
•
Expires: 1962-05-13
Abstract
No abstract record available.
Inventors
- 👤 Dalzell Charles Brown
- 👤 Wyman Ellsworth
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 11:32
CPC Classifications
F; F28; F28F; F28F3/00; F28F3/12; F28F3/02; F28F3/04; F28F3/042; F28F3/044; Y; Y10; Y10S; Y10S165/00; Y10S165/163; Y10S165/177; Y10S165/178
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
DE534014C
Cited
US785580A
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US791876A
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US1545893A
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US2133819A
Cited
US2097851A
Cited
US2061645A
Cited
US2120797A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1950-05-26 | 1950-11-25 | 1951-05-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1954-05-26 | 1954-11-25 | 1955-05-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1958-05-26 | 1958-11-25 | 1959-05-27 | $7700.00 | Window Closed / Lapsed |