Patent ID: 7404665

Claim:
Apparatus for processing a pre-comminuted plastic material comprising a screw rotatably supported in a housing having a filling opening, an upright receptacle for receiving material having a height and a lower outflow opening proximate a lower end of the receptacle in fluid communication with the filling opening for feeding the material to the screw, the receptacle defining an upper space and a lower space in fluid communication with the outflow opening which forms a dwell space for the material while material is being processed, first and second tools rotatably arranged in the receptacle for acting on the material, the second tool being arranged below the first tool, and a drive for rotating the first tool at a sufficient rotational speed so that the first tool introduces heat energy into the material in an upper space of the receptacle above the first tool and for rotating the second tool at a rate selected to introduce less heat energy into the material in a lower space of the receptacle below the first tool than the heat energy introduced into the material in the upper space so that the second tool thereby homogenizes the temperature of the material heated by the first tool and prevents an agglomeration of the material in the lower space.