Patent US2521369A successfully refreshed from Google Patents.
US2521369A
Expired / Lapsed
US
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Multifluid heat exchanger
Assignee: Alstom Power Inc
•
Filing: 1944-11-03
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Granted: 1950-09-05
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Expires: 1964-11-03
Abstract
No abstract record available.
Inventors
- 👤 Holm Sven
- 👤 Karlsson Per Hilmer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 14:50
CPC Classifications
F; F28; F28D; F28D7/00; F28D7/10; F28D7/103; F25; F25J; F25J5/00; F25J5/002; Y; Y10; Y10S; Y10S62/00; Y10S62/902; Y10S62/903; Y10S62/904; Y10T; Y10T29/00; Y10T29/49; Y10T29/4935
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US621537A
Cited
US1763012A
Cited
GB320279A
Cited
GB326278A
Cited
US2057804A
Cited
US2186077A
Cited
GB538391A
Cited
GB615919A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1953-09-04 | 1954-03-06 | 1954-09-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1957-09-04 | 1958-03-06 | 1958-09-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1961-09-04 | 1962-03-06 | 1962-09-05 | $7700.00 | Window Closed / Lapsed |