US3943034A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Dewatering and homogenizing apparatus
Assignee: Lennart Wallen and Co AB
•
Filing: 1974-04-05
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Granted: 1976-03-09
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Expires: 1994-04-05
Abstract
Abstract Dewatering and homogenizing apparatus comprising a screw thickener at the discharge end provided with a plug forming means actuated by pulling means. At the thickener's discharge end there is also mounted a hood for receiving dewatered pulp and with supply means for homogenizing agent.
Inventors
- 👤 Lennart E. O. Wallen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 14:29
CPC Classifications
D; D21; D21F; D21F1/00; D21F1/66; B; B01; B01D; B01D29/00; B01D29/11; B01D29/117; B01D29/118; B01D29/62; B01D29/64; B01D29/6469; B01D29/6476; B01D29/76; B01D29/80; B01D29/82; B01D29/828; B01D29/84; B01D29/843; B01D29/88; B01D29/94; B30; B30B; B30B9/00; B30B9/02; B30B9/12; B30B9/121; B30B9/18; D21B; D21B1/00; D21B1/04; D21B1/12; D21B1/14; D21B1/26; D21B1/30; D21B1/32; B01D2201/00; B01D2201/02; B01D2201/18; B01D2201/184; Y; Y02; Y02W; Y02W30/00; Y02W30/50; Y02W30/64
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
216 words
An apparatus for dewatering and homogenizing a pulp suspension and comprising a screen drum having inlet and outlet ends and tapering from the inlet end to the outlet end, a rotative shaft extending through the drum and beyond both ends of the drum, means for enclosing the drum radially throughout its length while leaving its outlet end axially open around the shaft, plug-forming means surrounding the shaft at the drum's outlet end and movable towards and from the outlet end, the shaft having screw-flights of helicoid shape inside of the drum and radially tapering from the drum's inlet to its outlet end, for forcing pulp when fed to its inlet end against the plug-forming means, means for forming a chamber having a fluid inlet and an outlet, the chamber fluid-tightly enclosing the drum's outlet and plug-forming means, the adjacent end of the shaft extending through the chamber and having a journaled end on the outside of the chamber and free from the chamber's inside, and means inside of the chamber and extending radially from the plug-forming means and forming backward extending tension members extending backwardly through the chamber to its outside and externally of said screen drum for receiving backward-pulling force applied on the chamber's outside for biasing the plug-forming means towards the drum's outlet end.
Claim 2
Independent Claim
216 words
An apparatus for dewatering and homogenizing a pulp suspension and comprising a screen drum having inlet and outlet ends and tapering from the inlet end to the outlet end, a rotative shaft extending through the drum and beyond both ends of the drum, means for enclosing the drum radially throughout its length while leaving its outlet end axially open around the shaft, plug-forming means surrounding the shaft at the drum's outlet end and movable towards and from the outlet end, the shaft having screw-flights of helicoid shape inside of the drum and radially tapering from the drum's inlet to its outlet end, for forcing pulp when fed to its inlet end against the plug-forming means, means for forming a chamber having a fluid inlet and an outlet, the chamber fluid-tightly enclosing the drum's outlet and plug-forming means, the adjacent end of the shaft extending through the chamber and having a journaled end on the outside of the chamber and free from the chamber's inside, and means inside of the chamber and extending radially from the plug-forming means and forming backward extending tension members extending backwardly through the chamber to its outside and externally of said screen drum for receiving backward-pulling force applied on the chamber's outside for biasing the plug-forming means towards the drum's outlet end.
Claim 3
Dependent Claim
73 words
The apparatus of claim 1 in which the shaft is hollow at least from adjacent to the drum's outlet end to the shaft's journaled end on the outside of the fluid-tight enclosing chamber for the drum's outlet end, and at least one of the screw-flights adjacent to the drum's outlet end is hollow and has holes facing backwardly, the hollow screw-flight communicating with the shaft's hollow portion and this portion having an outlet.
Claim 4
Dependent Claim
22 words
The apparatus of claim 1 in which the chamber's outlet has means for passing pulp while substantially holding fluid-pressure in the chamber.
Claim 5
Dependent Claim
12 words
The apparatus of claim 1 in which the shaft is axially movable.
Claim 6
Dependent Claim
21 words
The apparatus of claim 1 in which the said journaled end of the shaft has means for rotatively driving the shaft.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-03-09 | 1979-09-08 | 1980-03-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-03-09 | 1983-09-08 | 1984-03-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-03-09 | 1987-09-08 | 1988-03-09 | $7700.00 | Window Closed / Lapsed |