FIELD: process engineering.
SUBSTANCE: invention relates to injection moulding machine to produce covers with base wall holes, and to moulding core. Moulding core 220 comprises moulding pin 222 with cavity and end wall 224. Channel, preferably, in the form of hollow tube 66 enters the moulding pin cavity. Tube end is sealed and arranged at a certain distance from end wall of moulding pin. Plate valve 254 is arranged on moulding pin end wall. Plate valve is to respond to channel air pressure to open/close air flow passage in said end wall to facilitate separation of moulded articles from core pin. Plate valve comprises element 256 with outer edge on end surface of moulding pin and inner edge nearby channel end. Spring 260 preferably displaces valve element into closed position. Said spring represents preferably a coil spring compressed between valve element and moulding pin.
EFFECT: possibility to withdraw plate from injection mould cover.
19 cl, 18 dwg
