US3074842A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Treatment of unbleached cellulose pulps
Assignee: Dorr Oliver Inc
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Filing: 1959-07-24
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Granted: 1963-01-22
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Expires: 1979-07-24
Abstract
No abstract record available.
Inventors
- 👤 Michael D Strong
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 18:19
CPC Classifications
D; D21; D21C; D21C9/00; D21C9/10
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
155 words
THE METHOD OF TREATING FIBROUS CELLULOSIC STOCK WITH A GASEOUS TREATING GENT, WHICH COMPRISES CONTINUOUSLY DEWATERING THE STOCK BY PASSAGE THROUGH A CONTINUOUSLY OPERATING CENTRIFUGAL SCREEN POVIIDED WITH HELICAL DISCHARGE SCREW TO A CONSISTENCY WHERE THE FIBROUS ELEMENTS OF THE STOCK RATHER THAN THE LIQUID CONTROL THE PHYSICAL SHAPE OF THE FIBROUS MASS, WITH THE HELICAL SCREW COOPERATING WITH THE SCREEN EFFECTIVE TO CONTINUOUSLY DISCHARGE THE DEWATERED MATERIAL IN THE FORM OF DICRETE CLUSTERS OF FIBROUS ELEMENTS CONSTITUTING SPONGY STRUCTURES WHEREIN THE FIBERS HAVE RETAINED THEIR NATURAL RESILIENCY, AND WHICH CLUSTERS ARE THEREFORE SUBJECT TO UNIFORM GAS PENETRATION; CONTINUOUSLY SUPPLYING SUCH CLUSTERS TO A GAS REACTION CHAMBER THROUGH WHICH IS KEPT PASSING A CONTINUOUS FLOW OF TREATMENT GAS; CONTINUOUSLY MOVING SAID CLUSTERS THROUGH SAID CHAMBER AT A SUBSTANTIALLY UNIFORM CONTROLLED SPEED IN COUNTER-CURRENT TO SAID FLOW OF GAS REACTING UNIFORMLY THEREWITH BECAUSE OF SAID UNIFORM PENETRATION; AND SUBJECTING GAS-TREATED CLUSTERS TO REPULPING AND TO WASHING.
Claim 2
Independent Claim
155 words
THE METHOD OF TREATING FIBROUS CELLULOSIC STOCK WITH A GASEOUS TREATING GENT, WHICH COMPRISES CONTINUOUSLY DEWATERING THE STOCK BY PASSAGE THROUGH A CONTINUOUSLY OPERATING CENTRIFUGAL SCREEN POVIIDED WITH HELICAL DISCHARGE SCREW TO A CONSISTENCY WHERE THE FIBROUS ELEMENTS OF THE STOCK RATHER THAN THE LIQUID CONTROL THE PHYSICAL SHAPE OF THE FIBROUS MASS, WITH THE HELICAL SCREW COOPERATING WITH THE SCREEN EFFECTIVE TO CONTINUOUSLY DISCHARGE THE DEWATERED MATERIAL IN THE FORM OF DICRETE CLUSTERS OF FIBROUS ELEMENTS CONSTITUTING SPONGY STRUCTURES WHEREIN THE FIBERS HAVE RETAINED THEIR NATURAL RESILIENCY, AND WHICH CLUSTERS ARE THEREFORE SUBJECT TO UNIFORM GAS PENETRATION; CONTINUOUSLY SUPPLYING SUCH CLUSTERS TO A GAS REACTION CHAMBER THROUGH WHICH IS KEPT PASSING A CONTINUOUS FLOW OF TREATMENT GAS; CONTINUOUSLY MOVING SAID CLUSTERS THROUGH SAID CHAMBER AT A SUBSTANTIALLY UNIFORM CONTROLLED SPEED IN COUNTER-CURRENT TO SAID FLOW OF GAS REACTING UNIFORMLY THEREWITH BECAUSE OF SAID UNIFORM PENETRATION; AND SUBJECTING GAS-TREATED CLUSTERS TO REPULPING AND TO WASHING.
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) | 1966-01-21 | 1966-07-23 | 1967-01-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1970-01-21 | 1970-07-23 | 1971-01-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1974-01-21 | 1974-07-23 | 1975-01-22 | $7700.00 | Window Closed / Lapsed |