METHOD FOR DISCHARGING GAS FROM A PLASTIC INJECTION MOLD USING A VENTING CORE SYSTEM AND A TIMER APPARATUS TO REMOVE THE FLOW RESISTANCE CAUSED BY THE RESIDUAL GAS IN THE MOLD

摘要

PURPOSE: A method for discharging gas from a plastic injection mold using a venting core system and a timer apparatus is provided to implement low-pressure injection molding by preventing partial shrinkage.;CONSTITUTION: A venting core system(6) is installed in the inner charge end of the cavity(2) of a plastic injection mold and operated with a hydraulic/pneumatic cylinder(5) and a solenoid valve(4). A timer apparatus(3) is connected to the solenoid valve and transmits control output, which is delayed from an injection signal, to the solenoid valve so that the hydraulic/pneumatic cylinder is activated and a venting core is advanced to close a gas outlet and an air inlet. After the completion of injection molding, a mold is opened and the venting core is retracted so that the gas begins to be discharged.;COPYRIGHT KIPO 2011