Non-return flow injection moulding

摘要

Thermoplastic material is plasticised by a helical screw whose nose is cylindrical. The screw cannot move axially. The liner which surrounds the screw acts as the injection piston, and during the plasticising period it is withdrawn and moves forward for the injection stroke. This sleeve slides overt the cylindrical nose of the screw and prevents any return flow of plastics material. All kinds of plastics can be injection moulded by this arrangement.