Air classifier with sifting rotor and method for separation of the prior art

摘要

The wind sifter has at least one sifter rotor (4). The cross-sectional faces of the rotor passages (4.2) through which the air passes are designed so that the ratio of the forces acting upon the particles over a substantial part of the passages is constant up to a maximum deviation of plus or minus 10 per cent. The rotor blades are conical in shape and their apexes point inwards. The sides of the conical blades 4.1 of the sifter rotor may have two different pulling radii.