Patent US781885A successfully refreshed from Google Patents.
Patent US2138180A successfully refreshed from Google Patents.
US2138180A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Ventilator of the louver type
Assignee: Individual
•
Filing: 1937-03-31
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Granted: 1938-11-29
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Expires: 1957-03-31
Abstract
No abstract record available.
Inventors
- 👤 Lehmkuhl Joakim
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 18:38
CPC Classifications
F; F24; F24F; F24F13/00; F24F13/08; F24F13/10; F24F13/14; F24F13/1426; E; E06; E06B; E06B3/00; E06B3/32; E06B3/48; E06B3/481; F24F13/1413; F24F2013/1473
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) | 1941-11-28 | 1942-05-30 | 1942-11-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1945-11-28 | 1946-05-30 | 1946-11-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1949-11-28 | 1950-05-30 | 1950-11-29 | $7700.00 | Window Closed / Lapsed |