Patent US2390227A successfully refreshed from Google Patents.
US2390227A
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US
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Damper construction
Assignee: Henry Pratt Co LLC
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Filing: 1944-07-31
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Granted: 1945-12-04
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Expires: 1964-07-31
Abstract
No abstract record available.
Inventors
- 👤 William S Smith
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 15:52
CPC Classifications
F; F24; F24F; F24F13/00; F24F13/08; F24F13/10; F24F13/14; F24F13/15; G; G01; G01M; G01M9/00; G01M9/02; G01M9/04
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) | 1948-12-03 | 1949-06-04 | 1949-12-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1952-12-03 | 1953-06-04 | 1953-12-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1956-12-03 | 1957-06-04 | 1957-12-04 | $7700.00 | Window Closed / Lapsed |