Sieve arrangement for working with granular or powdered material

摘要

The sieve arrangement has a main sieve (2) and a pre-sieve (16) which is relatively movable with respect to the main sieve. Main (17) and auxiliary (18) beating units are associated with the main and pre-sieves respectively. Both sieves are cylindrical, with the pre-sieve and auxiliary beating unit being rotatable at various speeds, and the auxiliary beating unit being rotatably supported on the drive axle (7) of the pre-sieve. An auxiliary axle (23) drives the auxiliary beating unit via the drive axle, with both axles being associated with drive wheels (10,25) of differing operational diameter which are linked to a drive motor (14). The auxiliary beating unit is formed as a conveyor screw having a lower conveying power than a feed screw (5) of an intake (4) of the pre-sieve, and also has an air channel (30) and is supported at a flushing chamber (32).