US2073891A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Means for interchanging the functions of complementary heat exchange elements
Assignee: BALDWIN SOUTHWARK CORP
•
Filing: 1933-05-31
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Granted: 1937-03-16
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Expires: 1953-05-31
Abstract
No abstract record available.
Inventors
- 👤 Vogler Joseph
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 14:07
CPC Classifications
F; F25; F25B; F25B13/00; F25B2313/00; F25B2313/027; F25B2313/02732; Y; Y10; Y10T; Y10T137/00; Y10T137/6416; Y10T137/6525; Y10T137/8593; Y10T137/87153; Y10T137/87161; Y10T137/87249
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) | 1940-03-15 | 1940-09-14 | 1941-03-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1944-03-15 | 1944-09-14 | 1945-03-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1948-03-15 | 1948-09-14 | 1949-03-16 | $7700.00 | Window Closed / Lapsed |