US2807330A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and apparatus for filtering air
Assignee: American Air Filter Co Inc
•
Filing: 1954-08-04
•
Granted: 1957-09-24
•
Expires: 1974-08-04
Abstract
No abstract record available.
Inventors
- 👤 Richard D Rivers
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 02:20
CPC Classifications
F; F24; F24F; F24F13/00; F24F13/28; B; B01; B01D; B01D39/00; B01D39/14; B01D46/00; B01D46/18
Claims Analysis
Total Claims: 0
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1960-09-23 | 1961-03-25 | 1961-09-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1964-09-23 | 1965-03-25 | 1965-09-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1968-09-23 | 1969-03-25 | 1969-09-24 | $7700.00 | Window Closed / Lapsed |