US3452874A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Trunnion valve for continuous rotary filters
Assignee: Dorr Oliver Inc
•
Filing: 1967-11-02
•
Granted: 1969-07-01
•
Expires: 1987-11-02
Abstract
No abstract record available.
Inventors
- 👤 Leon D Keller
- 👤 Eric L Sandstrom
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 12:02
CPC Classifications
B; B01; B01D; B01D33/00; B01D33/80; B01D33/82; B01D33/06; B01D2201/00; B01D2201/16
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
US2899068A
Cited
US2289762A
Cited
US3027011A
Cited
US3220554A
Cited
US3193105A
Cited
US3409134A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1972-06-30 | 1972-12-30 | 1973-07-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1976-06-30 | 1976-12-30 | 1977-07-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1980-06-30 | 1980-12-30 | 1981-07-01 | $7700.00 | Window Closed / Lapsed |