Patent US1823481A successfully refreshed from Google Patents.
US1823481A
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US
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Heat exchange device
Assignee: Ljungstroms Angturbin AB
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Filing: 1928-10-02
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Granted: 1931-09-15
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Expires: 1948-10-02
Abstract
No abstract record available.
Inventors
- 👤 Zander Henrik
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 12:58
CPC Classifications
F; F23; F23M; F23M20/00; Y; Y10; Y10S; Y10S165/00; Y10S165/009; Y10S165/013; Y10S165/016
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) | 1934-09-14 | 1935-03-16 | 1935-09-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1938-09-14 | 1939-03-16 | 1939-09-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1942-09-14 | 1943-03-16 | 1943-09-15 | $7700.00 | Window Closed / Lapsed |