Patent ID: 11925911
Assignee: COLMEC S.P.A.
Field: Other special machines (Mechanical engineering)
Classification: CPC B | IPC B

Claim 0:
1. An apparatus for the mixing and extrusion of plastic materials, comprising:
a dump extruder body;
an extrusion die (3);
two conical screws mounted on the dump extruder body and converging towards the extrusion die (3);
a closing means (4);
wherein 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 compounding chamber (1) corresponding to an upstream area with respect to an extrusion direction, characterized in that
in said high-pressure chamber (2′) there is provided a first presser body (5, 5′, 6), which forms a movable wall suitable for defining a controlled change in the volume of the respective chamber (2′), and wherein
said first presser body (6) is displaced in position at least during a compounding step wherein said closing means (4) prevent the plastic material from passing through said extrusion die (3).