Plasticising unit for injection moulding machine

摘要

Molten polymer is conveyed into the area in front of the screw and then forced by axial screw movement into a tool. Back flow of the polymer is prevented by a non-return valve which creates a high pressure zone in front and a lower pressure behind the valve. The plasticizing barrel comprises two parts, namely a barrel head which always and completely encloses the non-return valve and the high pressure zone and also a barrel which surrounds the screw and the low pressure zone. Even when the screw is in the farthest retracted position the joint between the barrel and the barrel head always lies within the low pressure zone.