Patent US3393687A successfully refreshed from Google Patents.
US3423906A
Expired / Lapsed
US
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Apparatus for removing particles from air
Assignee: F W MEANS AND CO
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Filing: 1968-01-26
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Granted: 1969-01-28
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Expires: 1988-01-26
Abstract
No abstract record available.
Inventors
- 👤 Robert A Fried
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 14:19
CPC Classifications
B; B01; B01D; B01D46/00; B01D46/42; B01D46/48; B01D46/0027; B01D46/0035; B01D46/24; B01D46/66; B01D46/70; B01D2273/00; B01D2273/30
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1972-01-28 | 1972-07-29 | 1973-01-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1976-01-28 | 1976-07-29 | 1977-01-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1980-01-28 | 1980-07-29 | 1981-01-28 | $7700.00 | Window Closed / Lapsed |