Shut-off nozzle for injection molding machine

摘要

A shut-off nozzle assembly for injection molding machines includes a nozzle body with high pressure flat face male-female rear and front flange connections connecting the nozzle body to a machine adaptor and a nozzle tip or nozzle tip extension, respectively. The shut-off includes a reciprocating valve pin moved by a pair of diametrically arranged exterior actuators mounted on a two-part mounting plate secured to the interior of the rear flange. The actuators drive the pin through a pair of actuator arms extending through a transverse slot in the nozzle body. The machine adaptor and body include four angled and paired passages forming a resin flow path bypassing the pin and slot with adequate wall thickness. The passages in the nozzle body are less steeply angled and are provided with an elliptical bell mouth at the flange connection flat face joining the more sharply angled passages in the machine adaptor. The passage arrangement and the male-female flat face flange connections enable the shut-off to be operated efficiently and effectively at very high pressures.