Patent ID: 7216822

Claim:
An agitator mill for treating free-flowing grinding stock, comprising a grinding receptacle ( 2 ) which defines a substantially closed grinding chamber ( 8 ) by means of an inner wall ( 9 ); and an agitator ( 20 ) which is rotarily drivably disposed therein and which is cup-shaped in relation to a common central longitudinal axis ( 19 ), having an annular cylindrical rotor ( 39 ) which has a closed wall ( 40 , 41 ); and an interior stator ( 22 ) which is disposed within the rotor ( 39 ) and fixedly joined to the grinding receptacle ( 2 ); wherein an annular cylindrical exterior grinding chamber ( 8 a ) in the form of an annular gap is formed between the inner wall ( 9 ) of the grinding receptacle ( 2 ) and an outer wall ( 40 ) of the rotor ( 39 ), the exterior grinding chamber ( 8 a ) having a radial gap width g; wherein an annular cylindrical interior grinding chamber ( 8 b ) in the form of an annular gap is formed between an inner wall ( 41 ) of the rotor ( 39 ) and an outer casing ( 23 ) of the interior stator ( 22 ), the interior grinding chamber ( 8 b ) being arranged coaxially within the exterior grinding chamber ( 8 a ) and connected thereto via a deflection chamber ( 50 ) and having a radial gap width h; wherein the exterior grinding chamber ( 8 a ), the deflection chamber ( 50 ) and the interior grinding chamber ( 8 b ) constitute the grinding chamber ( 8 ) which is partially filled with auxiliary grinding bodies ( 38 ); wherein a grinding-stock supply area ( 57 ), which is disposed upstream of the exterior grinding chamber ( 8 a ) and opens into the exterior grinding chamber ( 8 a ) in the direction of flow ( 60 ) of the grinding stock, and a separator device ( 32 ), which is disposed downstream of the interior grinding chamber ( 8 b ) in the direction of flow ( 60 ), are disposed approximately on the same side of the grinding receptacle ( 2 ) for the grinding stock to pass through; wherein auxiliary-grinding-body return conduits ( 54 ) are provided in the agitator ( 20 ) for returning the auxiliary grinding bodies ( 38 ) from the vicinity of the separator device ( 32 ) into the grinding-stock supply area ( 57 ), the return conduits ( 54 ) connecting the end of the interior grinding chamber ( 8 b ) to the beginning of the exterior grinding chamber ( 8 a ); wherein the inner wall ( 9 ) of the grinding receptacle ( 2 ) and the outer wall ( 40 ) and the inner wall ( 41 ) of the rotor ( 39 ) are free of interruptions, and the inner wall ( 9 ) of the grinding receptacle ( 2 ) and the outer wall ( 40 ) of the rotor ( 39 ) are smooth and free of agitator implements; and wherein g<h applies to the radial gap width g of the exterior grinding chamber ( 8 a ) in relation to the radial gap width h of the interior grinding chamber ( 8 b ).