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US2695232A
Expired / Lapsed
US
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Apparatus for heating and controlling the temperature of a continuously operating cellulose digester
Assignee: Metso Fiber Karlstad AB
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Filing: 1951-07-07
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Granted: 1954-11-23
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Expires: 1971-07-07
Abstract
No abstract record available.
Inventors
- 👤 Richter Johan Christoffer Carl
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 15:40
CPC Classifications
D; D21; D21C; D21C7/00; D21C7/10; D21C7/12
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
104 words
IN A VERTICAL CYLINDRICAL DIGESTER THROUGH WHICH FIBROUS MATERIAL MIXED WHEN DIGESTING LIQUOR IS SLOWLY AND CONTINUOUSLY CONVEYED LONGITUDINALLY AND WHEREIN THE MATERIAL IS HEATED IN A ZONE SHORT RELATIVE TO THE LENGTH OF THE DIGESTER, THE COMBINATION COMPRISING A SIEVE ARRANGED IN THE CYLINDRICAL WALL OF THE DIGESTER FOR DRAWING DIGESTING LIQUOR SUBSTANTIALLY RADIALLY FROM THE HEATING ZONE, AND A TUBE EXTENDING ALONG APPROXIMATELY THE LONGITUDINAL AXIS OF THE DIGESTER THROUGH THE TOP END THEREOF TO THE HEATING ZONE FOR RETURNING HEATED LIQUOR TO ADJACENT THE CENTER OF THE HEATING ZONE, SAID TUBE BEING SUPPORTED SOLELY AT THE TOP END OF SAID DIGESTER.
Claim 2
Dependent Claim
104 words
IN A VERTICAL CYLINDRICAL DIGESTER THROUGH WHICH FIBROUS MATERIAL MIXED WHEN DIGESTING LIQUOR IS SLOWLY AND CONTINUOUSLY CONVEYED LONGITUDINALLY AND WHEREIN THE MATERIAL IS HEATED IN A ZONE SHORT RELATIVE TO THE LENGTH OF THE DIGESTER, THE COMBINATION COMPRISING A SIEVE ARRANGED IN THE CYLINDRICAL WALL OF THE DIGESTER FOR DRAWING DIGESTING LIQUOR SUBSTANTIALLY RADIALLY FROM THE HEATING ZONE, AND A TUBE EXTENDING ALONG APPROXIMATELY THE LONGITUDINAL AXIS OF THE DIGESTER THROUGH THE TOP END THEREOF TO THE HEATING ZONE FOR RETURNING HEATED LIQUOR TO ADJACENT THE CENTER OF THE HEATING ZONE, SAID TUBE BEING SUPPORTED SOLELY AT THE TOP END OF SAID DIGESTER.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1957-11-22 | 1958-05-24 | 1958-11-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1961-11-22 | 1962-05-24 | 1962-11-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1965-11-22 | 1966-05-24 | 1966-11-23 | $7700.00 | Window Closed / Lapsed |