Patent ID: 7891593

Claim:
Device for comminuting a heap of particulate material, comprising a framework-supported housing with a vertical axis which is provided at its upper end with at least one inlet opening for the heap and at its lower end with an outlet; a drive shaft which is arranged vertically and centrally in the housing and is driven by a drive motor; and a rotor which is mounted on the drive shaft and has a plurality of rotor elements which are offset in the circumferential direction and/or with an axial spacing and which extend, at least while the rotor is rotating, close to the actual housing wall in order to process the downwardly falling heap, wherein the housing ( 10 , 10 a ) has at least two housing sections ( 12 to 16 , 12 a to 16 a , 14 b , 16 b ) arranged vertically above one another, of which the lower section, at least in the upper region adjoining the section above it, has a larger diameter than the adjoining region of the upper housing section, and the radial extent of the rotor elements ( 34 , 34 a , 52 , 54 ) in the upper region of the lower housing section is larger than the diameter of the lower region of the housing section situated above it, and that one shaft respectively is assigned to a housing section or an associated group of housing sections, the shafts coaxially lying to each other and being independently drivable.