Assembly hole forming method of injection molded article and core pin for forming assembly hole

摘要

The present invention relates to an injection molding method and an injection molding method in which an assembly hole inner diameter of an injection molded product is automatically machined in a mold or simultaneously with the size of an inner diameter of an assembly hole, And a core pin for forming an assembly hole, characterized in that the core pin for forming an injection-molded article is removed by a slope of a predetermined angle so as to be smoothly detached from the assembly hole of the injection-And a core pin 10 having a tapered portion 16 formed at an upper end of the core pin 10 and provided with an and having a cutting edge 12 for cutting the inner diameter of the assembly hole at a predetermined dimension when the injection-Or when the injection-molded article is taken out at the upper end of the core pin 20, the inner diameter of the hole of the cooking hole is forcibly pushed so that the inner diameter of the assembly hole is adjusted to a certain dimension And protrusions 22 are formed so as to protrude therefrom.