| 摘要 |
To provide a bowling pin which exhibits a pin action of the bowling pin which is generated due to strong hitting of the ball with the bowling pin close to a pin action of a conventional bowling pin. An upper core 25 and a lower core 23 are set in a core material forming mold 21, a molten synthetic resin is injected into a cavity 27 through a gate 26 and is cooled and, thereafter, the upper and lower cores are removed thus forming by molding the core material 3 which includes an upper hollow portion 5a having an upper opening, a lower hollow portion 5b having a lower opening and a circumferential groove 4a which surrounds a largest diameter portion of the core material and, thereafter, a resilient strip 4 is formed by filling a synthetic resin softer than a synthetic resin for forming the core material into the circumferential groove, an upper cap is mounted on the upper hollow portion and a lower cap is mounted on the lower hollow portion, a projecting portion of the upper cap is inserted into a recessed portion of an upper mold thus forming an upper engaging portion, a pin of a lower mold is inserted into a recessed portion of the lower cap thus forming a lower engaging portion, the core material is vertically fixed to the inside of the cavity while maintaining a gap around the core material, and a molten resin is injected into the gap through a gate thus covering the upper and lower caps, the resilient strip and the core material with the skin portion.
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