The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 09, 1993
Filed:
Aug. 14, 1990
Frey Frejborg, Glen Falls, NY (US);
A. Ahlstrom Corporation, Noormarkku, FI;
Abstract
An apparatus for screening pulp comprises a vessel, a cylindrical screen within the vessel, a rotor moving in the vicinity of the screen at a predetermined speed, an inlet for the unscreened pulp, an outlet for the screened pulp in the vessel. The rotor is non-cylindrical, for instance, elliptical, triangular, and in general, is multi-cam. The rotor has a contour surface which is achieved by attaching bars of the contoured shape to the surface of the rotor, for instance by welding. According to one embodiment, the contour surface of the rotor is discontinuous. The bars form a plurality of spaced protrusions instead of a single protrusion along the entire axial length of the rotor.