US1794841A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Filtration system
Assignee: Cochrane Corp
•
Filing: 1924-01-11
•
Granted: 1931-03-03
•
Expires: 1944-01-11
Abstract
No abstract record available.
Inventors
- 👤 Harold D Elfreth
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 11:11
CPC Classifications
B; B01; B01D; B01D24/00; B01D24/38; B01D24/42; B01D24/02; B01D24/10; B01D24/14; B01D24/46; B01D24/4631; B01D24/4636; B01D24/4668; B01D24/4684
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1934-03-02 | 1934-09-01 | 1935-03-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1938-03-02 | 1938-09-01 | 1939-03-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1942-03-02 | 1942-09-01 | 1943-03-03 | $7700.00 | Window Closed / Lapsed |