| 摘要 |
PROBLEM TO BE SOLVED: To prevent the generation of overpack, flash and the like and the generation of short of a package part by providing a slidable pin on a sprue section of an injection molding die in the shotting process of a polymer, forming a space in the mold by the slide of the pin and reducing the internal pressure of the mold. SOLUTION: A mounted ceramic base 9 is fixed in mold by a package part 11 and the like, and mold clamping is carried out, and then a liquid crystal polymer 13 is shotted by an injection molding machine. Although the liquid crystal polymer 13 is of low viscosity, its melting temperature is high and high speed shotting is applied for the purpose of reducing the damage to the base caused by heat. Therefore, overpack, flash, short and the like are generated even when the stopping of a screw or the secondary pressure changeover is carried out just after the completion of shotting. A pressure reducing pin 14 provided on a sprue section 5, therefore, is moved in the arrow direction synchronously with the stopping of the screw or the secondary pressure changeover to form a space in the mold and eliminate the residual pressure. |
