US2528539A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Air filter
Assignee: NORGREN
•
Filing: 1945-10-22
•
Granted: 1950-11-07
•
Expires: 1965-10-22
Abstract
No abstract record available.
Inventors
- 👤 Carl A Norgren
- 👤 Kenneth C Mosier
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 07:41
CPC Classifications
B; B01; B01D; B01D46/00; B01D46/0027; B01D46/003; B01D46/0031; B01D39/00; B01D39/10; B01D39/12; B01D46/0036; B01D46/24; B01D46/2403; B01D50/00; B01D50/20; B04; B04C; B04C1/00
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1423412A
Cited
US1771042A
Cited
GB345672A
Cited
US2044095A
Cited
US2009352A
Cited
US2068048A
Cited
US2144681A
Cited
US2170074A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1953-11-06 | 1954-05-08 | 1954-11-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1957-11-06 | 1958-05-08 | 1958-11-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1961-11-06 | 1962-05-08 | 1962-11-07 | $7700.00 | Window Closed / Lapsed |