| 摘要 |
PROBLEM TO BE SOLVED: To provide a method and device for manufacturing a piston for internal combustion engine, capable of disposing a wear resisting ring and an annular cavity at an upper position within a crown part as much as possible while enhancing running property in a gap between the wear-resisting ring and a salt core to increase the density.SOLUTION: The method for manufacturing the piston includes a lower mold 10 in which the salt core 17 for forming the annular cavity within a cavity 13 is preliminarily disposed and fixed, an upper mold 11 opening and closing the upper end opening of the cavity, and a holding mechanism 12 provided on the upper mold to preliminarily hold the wear-resisting ring 5 in a detachable manner. After molten metal Q injected into the cavity is brought into contact with a part of the salt core, the upper mold and the holding mechanism are lowered in the direction of the cavity to move the wear-resisting ring to the outside of the salt core, and the mutual positions of the wear-resisting ring and the salt core are overlapped with each other in the direction of the piston axis. According to this, the agitating property or flowability of the molten metal within a gap width L of the both at this movement time is obtained to improve the running property. |
