US2815826A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Air filtration
Assignee: Individual
•
Filing: 1955-05-05
•
Granted: 1957-12-10
•
Expires: 1975-05-05
Abstract
No abstract record available.
Inventors
- 👤 Frank W Young
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 04:06
CPC Classifications
F; F24; F24F; F24F13/00; F24F13/28; B; B01; B01D; B01D39/00; B01D39/02; B01D39/06; B01D46/00; B01D46/18; F24F2203/00; F24F2203/12
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US140034A
Cited
US1322804A
Cited
US1472574A
Cited
FR553540A
Cited
US1995378A
Cited
US2152900A
Cited
US2352303A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1960-12-09 | 1961-06-10 | 1961-12-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1964-12-09 | 1965-06-10 | 1965-12-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1968-12-09 | 1969-06-10 | 1969-12-10 | $7700.00 | Window Closed / Lapsed |