Local compressed type injection molding manner and local compressed type injection molding machine

摘要

PURPOSE: To prevent generation of sink marks at flow end and thick part in a cavity and prevent generation of inner warp caused by unbalanced shrinkage of lines. ;CONSTITUTION: By making a first local pressing pin 34 move forward, a resin in the front of it is pushed into a cavity 21. By making a second local pressing pin 35 move forward, a resin in the front of it is pushed into the cavity 21. A timing for starting the forward movement of the first local pressing pin 34 is differentiated from a timing for starting the forward movement of the second local pressing pin 35. When one of the first and second local pressing pins 34 and 35 moves forward and the other pin out of them starts to move forward thereafter, the other pin out of the first and second local pressing pins 34 and 35 pushes the resin in the front into the cavity 21.;COPYRIGHT: (C)1995,JPO