Patent US3897337A successfully refreshed from Google Patents.
Patent US2074801A successfully refreshed from Google Patents.
US2074801A
Expired / Lapsed
US
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Heat exchange and air washing device
Assignee: Sullivan Machinery Co
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Filing: 1934-02-28
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Granted: 1937-03-23
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Expires: 1954-02-28
Abstract
No abstract record available.
Inventors
- 👤 Noble Warren
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 16:54
CPC Classifications
F; F04; F04B; F04B49/00; F04B49/22; F04B49/225; F04B39/00; F04B39/06; F04B39/16
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) | 1940-03-22 | 1940-09-21 | 1941-03-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1944-03-22 | 1944-09-21 | 1945-03-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1948-03-22 | 1948-09-21 | 1949-03-23 | $7700.00 | Window Closed / Lapsed |