US1680145A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Heat exchanger
Assignee: Individual
•
Filing: 1925-01-27
•
Granted: 1928-08-07
•
Expires: 1945-01-27
Abstract
No abstract record available.
Inventors
- 👤 Forssblad Nils Richard
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 06:42
CPC Classifications
F; F28; F28D; F28D9/00; F28D9/0062; F28F; F28F3/00; F28F3/08; F28F3/083; F28G; F28G9/00; F28F2250/00; F28F2250/10; F28F2250/108
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) | 1931-08-07 | 1932-02-06 | 1932-08-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1935-08-07 | 1936-02-06 | 1936-08-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1939-08-07 | 1940-02-06 | 1940-08-07 | $7700.00 | Window Closed / Lapsed |