Patent US1831533A successfully refreshed from Google Patents.
US1831533A
Expired / Lapsed
US
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Heat exchange device
Assignee: Babcock and Wilcox Co
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Filing: 1929-01-08
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Granted: 1931-11-10
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Expires: 1949-01-08
Abstract
No abstract record available.
Inventors
- 👤 Hubbard Norman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 19:03
CPC Classifications
F; F28; F28F; F28F3/00; F28F3/08; F28F3/083; Y; Y10; Y10S; Y10S165/00; Y10S165/355; Y10S165/356; Y10S165/387; Y10S165/388
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1934-11-09 | 1935-05-11 | 1935-11-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1938-11-09 | 1939-05-11 | 1939-11-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1942-11-09 | 1943-05-11 | 1943-11-10 | $7700.00 | Window Closed / Lapsed |