Pulping apparatus including improved rotor
AssigneeBeloit Corporation
InventorStavros Paraskevas
Life of this patent
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Abstract
An improved pulping apparatus having a rotor with a special vane design providing improved defibering action as well as improved circulation. The rotor cooperates with a perforated extraction plate and has a plurality of outwardly extending vanes each having a surface arranged to cooperate with the perforated extraction plate, a smoothly contoured airfoil surface which receives the stock, a leading face and a trailing surface, the leading face having a concave trough-like surface extending for substantially the entire length of the vane.
Claims7
A rotor for use in association with an extraction plate adapted for defibering liquid slurry stock and causing defibered material to pass through said extraction plate, said rotor comprising:
- a central body portion;
- a plurality of vanes extending in a generally tangential direction from said central body portion and each having an extraction side, a leading face and a trailing surface, the leading face of each vane including a generally circular convex forward edge of relatively small radius of curvature and which extends substantially linearly in said generally tangential direction, said forward edge merging into a concave central portion having a substantially larger radius of curvature than said small radius of curvature, said central portion merging into a smooth surfaced bottom face having a trailing edge, and a smoothly contoured convex airfoil trailing surface extending from said forward edge to the trailing edge of said bottom face.
In a pulping apparatus including:
- a tub,
- a rotor mounted for rotation about a vertical axis in said tub, and
- a perforate extraction plate disposed beneath said rotor for delivering defibered material therethrough, the improvement in the rotor structure which comprises:
- a rotor hub,
- a plurality of equally spaced vanes extending in a generally tangential direction from said hub,
- each of said vanes including a leading face with an upper portion including a generally circular convex forward edge of relatively small radius of curvature and which extends substantially linearly in said generally tangential direction, said leading edge merging into a concave central portion of substantially less pronounced curvature than said small radius of curvature, said central portion merging into a smooth surfaced bottom face having a trailing edge and positioned in closely spaced relation with said extraction plate,
- each vane further having a smoothly contoured airfoil trailing surface extending from said generally circular convex forward edge to the trailing edge of said bottom face.
Dependencies are inferred from the claim text.