Screw extruder for the continuous extrusion of thermoplastic materials

摘要

A temperable screw extruder for the continuous extrusion of thermoplastics materials wherein to increase the working and cooling of the material in the extruder without excessively increasing the length of the extruder means are provided to convey the material in a direction transverse to the axis of a main screw away from said axis and then to convey it back theretowards. Preferably said means comprises, located between the main screw and an extrusion outlet orifice, a transverse screw disposed in a transverse cylinder chamber to direct the plastics melt outwardly transversely to the axis of the main screw, a connection passage at the end of the transverse chamber to a downstream further transverse chamber having a further transverse screw therein to convey the material back towards the axis of the main screw.