Air classifier

摘要

The invention relates to an air classifier (mechanical centrifugal separator) having a rotating classifying wheel (1 to 3), against which the fines-loaded classifying air flows against centrifugal force radially inwards from the outside, and from which said classifying air flows out axially through an outlet port (5, 6, 18) and which has an outflow-side back disc (1), a second back disc (2) disposed axially offset thereto, and between these has blades (3) arranged circumferentially. According to the invention, the outlet port (5, 6, 18) is run, by means of a plunge pipe section (5, 6) as far as into the outflow-side back disc (1) and is joined thereto in a torsion-proof manner. The outlet port (5, 6, 18) in this arrangement preferably has a section (5) in which the cross-section of the plunge pipe increases continuously. By means of an appropriate design of the second back disc (2), the classifying wheel may, at the same time, serve for size reduction of the material (Figure 2). <IMAGE>