TWIN-SCREW MIXER-EXTRUDER, INCLUDING A PRESSER BODY FOR DEFINING A CONTROLLED VOLUME OF A COMPOUNDING CHAMBER

摘要

It is described an apparatus for the extrusion and mixing of plastic materials, for example rubber-based and silicone-based materials, comprising a dump extruder body whereon two conical screws (2) converging towards an extrusion die (3) suitable for being occluded by closing means (4) are mounted, the conical screws (2) being accommodated within a low-pressure compounding chamber (1) and within a pair of converging conical channels also defining a high-pressure chamber (2′), said low-pressure chamber (1) corresponding to an upstream area with respect to an extrusion direction, wherein said high-pressure chamber (2′) and/or said low-pressure chamber (1) accommodate a presser body (5, 5′, 6), defining a movable wall suitable for causing a controlled change in the volume of the respective chamber (1, 2′).