US3637077A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Screen impeller
Assignee: Individual
•
Filing: 1969-10-27
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Granted: 1972-01-25
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Expires: 1989-10-27
Abstract
Abstract An impeller for installation within a pulp screening machine in which each blade of the impeller is provided with a white water dilution channel communicating with the hollow shaft for the purpose of projecting streams of white water against the inner face of the screen. These dilution channels are located in the same axial position on each set of radially opposite blades and on adjacent blades the dilution channels are offset longitudinally by one width of channel so that each longitudinal strip of the screen plate is cleaned by two dilution channels.
Inventors
- 👤 Ben Cowan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 07:58
CPC Classifications
B; B07; B07B; B07B1/00; B07B2230/00; B07B2230/01
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
206 words
In a pulp screen apparatus comprising a housing, a drum screen having an inlet end and a discharge end through said housing, inlet means for feeding pulp through said inlet end to the interior of said screen, means for discharging a reject fiber fraction from the interior of said drum discharge end, and means for discharging an accepts fiber fraction that passes through said screen from said housing, the improvement comprising an impeller comprising a shaft having at least a portion thereof hollow to form a white water supply duct, means for supplying white water to said duct, a series of blades mounted longitudinally on said shaft and extending substantially the length of said screen between said ends and radiating outwardly therefrom to a position adjacent the inner surface of said drum screen, a channel on one face of each of said blades, said channels communicating at their inner ends with said water supply duct and extending radially so that their outer ends are at the outer edges of said blades, said channels being separately disposed axially along the length of said shaft and being circumferentially offset relative to each other to project streams of white water radially against the inner surface of said drum screen.
Claim 2
Dependent Claim
206 words
In a pulp screen apparatus comprising a housing, a drum screen having an inlet end and a discharge end through said housing, inlet means for feeding pulp through said inlet end to the interior of said screen, means for discharging a reject fiber fraction from the interior of said drum discharge end, and means for discharging an accepts fiber fraction that passes through said screen from said housing, the improvement comprising an impeller comprising a shaft having at least a portion thereof hollow to form a white water supply duct, means for supplying white water to said duct, a series of blades mounted longitudinally on said shaft and extending substantially the length of said screen between said ends and radiating outwardly therefrom to a position adjacent the inner surface of said drum screen, a channel on one face of each of said blades, said channels communicating at their inner ends with said water supply duct and extending radially so that their outer ends are at the outer edges of said blades, said channels being separately disposed axially along the length of said shaft and being circumferentially offset relative to each other to project streams of white water radially against the inner surface of said drum screen.
Claim 3
Dependent Claim
48 words
An impeller as set forth in claim 1 in which said channels are of rectangular shape and narrow depth in a direction normal to the plane of the blades, the channel on one blade being offset axially by the width of the channel on the next adjacent blade.
Claim 4
Dependent Claim
22 words
An impeller as set forth in claim 1 in which said channels on radially opposite blades are in the same radial plane.
Claim 5
Dependent Claim
23 words
An impeller as set forth in claim 1 in which outlets of said channels are restricted to provide a narrow axially aligned nozzle.
Claim 6
Dependent Claim
29 words
An impeller as set forth in claim 1 in which the channels are located on the face of the blades opposite from the direction of rotation of the impeller.
Claim 7
Dependent Claim
41 words
An impeller as set forth in claim 1 in which the channels are disposed axially of the impeller from approximately one-third of the length of the impeller from the inlet end of the screen towards the discharge end of the screen.
Claim 8
Dependent Claim
38 words
An impeller as set forth in claim 1 in which said channels have a width axially of the blades of about 6 inches and a depth from the face of the blades of about three-quarters of an inch.
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) | 1975-01-24 | 1975-07-26 | 1976-01-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-01-24 | 1979-07-26 | 1980-01-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-01-24 | 1983-07-26 | 1984-01-25 | $7700.00 | Window Closed / Lapsed |