US2560874A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Centrifugal air cleaner
Assignee: Individual
•
Filing: 1950-04-06
•
Granted: 1951-07-17
•
Expires: 1970-04-06
Abstract
No abstract record available.
Inventors
- 👤 Kelso Frank
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 22:11
CPC Classifications
B; B01; B01D; B01D45/00; B01D45/12; B01D45/14
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1303207A
Cited
US1447160A
Cited
US1505564A
Cited
US1702424A
Cited
GB528726A
Cited
US2364279A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1954-07-16 | 1955-01-15 | 1955-07-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-07-16 | 1959-01-15 | 1959-07-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-07-16 | 1963-01-15 | 1963-07-17 | $7700.00 | Window Closed / Lapsed |