Patent US379040A successfully refreshed from Google Patents.
Patent US3579421A successfully refreshed from Google Patents.
US3579421A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Continuous cellulose digester with two separate pulp outlets
Assignee: Metso Fiber Karlstad AB
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Filing: 1968-05-13
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Granted: 1971-05-18
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Expires: 1988-05-13
Abstract
Abstract A CONTINUOUS CELLULOSE DIGESTER IS PROVIDED WITH TWO PULP DISCHARGING MEANS, ONE DISCHARGING THE CORE OF THE MOVING PLUG OF CELLULOSIC MATERIAL THROUGH A FIRST OUTLET AND THE OTHER DISCHARGING THE PERIPHERAL PARTS OF THE PLUG THROUGH A SECOND OUTLET. THE FIRST DISCHARGING MEANS MAY BE A ROTARY SCRAPER WORKING IN THE CENTER AREA ONLY OF THE OUTLET END OF THE DIGESTER, THE SECOND DISCHARGING MEANS WORKING IN THE SURRONDING ANNULAR SPACE. THE FIRST OUTLET AND DISCHARGING MEANS IS SEPARATED FROM THE SECOND OUTLET AND DISCHARGING MEANS BY A PARTITION MEANS WHICH IS CONCENTRIC TO THE DIGESTER WALL.
Inventors
- 👤 Johan C F C Richter
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 05:05
CPC Classifications
D; D21; D21C; D21C7/00; D21C7/08
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) | 1974-05-17 | 1974-11-16 | 1975-05-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-05-17 | 1978-11-16 | 1979-05-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-05-17 | 1982-11-16 | 1983-05-18 | $7700.00 | Window Closed / Lapsed |