Rotor-stator mixing apparatus especially for single screw extruder

• Main Author: Hilder, Robin
• Format: Patent
• Language: English
• Published: 08.07.2003

The present invention relates in one aspect to a single screw extruder for extruding combinations of materials such as thermoplastics polymers, rubbers, waxes and solid additives, and in another aspect to a mixer for such materials. The mixer could however be employed in the manufacture of inks, paints and other materials where one or more of the components is liquid at the room temperature. A single screw extruder comprises a mixer associated with the screw, and comprising a rotor driven by the screw and a stator, the rotor and the stator each carrying mutually facing interengaging rings of teeth whereby the material is urged outwardly from the screw along a first tortuous mixing path, and then returned inwardly to the screw along a second tortuous mixing path, with the teeth extending axially, or generally so, with respect to the longitudinal axis of the screw. The invention also includes a mixer comprising a cylindrical stator chamber having opposed, radially extending faces provided with axially projecting, radially spaced-apart rings made up of alternating teeth and ridges, a rotor rotatably fitted within the stator and provided on its opposite side faces with axially projecting, radially spaced-apart rings of alternating teeth and ridges with the rotor and stator rings interengaging with both radial and axial clearance so as to define a tortuous material flow path.