| 摘要 |
PURPOSE:To prevent generation of flashes, by a method wherein a thin collar becoming a seal preventing a leak of a molten material by being bent by pressing force of a mold is provided in a projected state in the fringe running along a boundary line between a head part and a part of a member main body to be buried into the head part. CONSTITUTION:A collar 14 is provided in a projected and tapered state in the fringe of the lower end part of a head part 13 formed of an aluminum alloy in a member main body 11 to be buried into the head part 13. The member main body 11 is outserted over a pin 6 stood up within a cavity 5 and held, with which the other mold 7 is pressure-contacted. With this construction, the head part 13 is fitted into the recessed part 8, an opening fringe of the recessed part 8 abuts against the collar 14 and the collar 14 is pressed within the cavity 5. Therefore the collar 14 is bent as it is stuck close to the opening fringe of the recessed part 8 and a gap between an inner circumferential surface of the recessed part 8 and an outer circumferential surface of the collar 14 is closed under a sealed state. Therefore, since injection molding is performed under this state, bathing of a molten material does not enter into the recessed part 8. |
