Bro - Bro of the molding apparatus - molding head

摘要

PURPOSE:To offset the amount of distortion caused by inner pressure at injection by generating a temperature difference between the inner and outer wall faces of a parison head main body or a nozzle flat hole. CONSTITUTION:A heater 15 is buried in the inner wall of a flat hole 2 of a parison head main body 1, and a cooling channel 16 is formed along the outer side of the parison head main body 1. By applying electric power to the heater 15 to heat up the inner wall face of the parison head main body 1 and flowing and cooling medium on the outer side, the inner wall face is swelled to the center because of difference of thermal expansion between the inner wall face and the outer wall face. By controlling cooling of the outer face, the volume of distortion can be controlled, and a correct shape of the flat hole 2 can be kept under inner pressure. The components can be kept in a shape as shown in chain lines by heating the outer face when the parison head is flattened, or cooling the inner face when the outer face is processed.