| 摘要 |
PURPOSE:To prevent the leak of cooling oil and improve the cooling effect by fixing a soluble core by a pin which penetrates through a seat metal having a pin hole and cast-enclosing the seat metal inside a piston and closing a hole on a supporting body by the seat metal. CONSTITUTION:A salt core 22 is set through a supporting body 20 and a pin 21 onto a core 19, and the salt core 22 is arranged in a metal mold, and the molten aluminum alloy is poured, and the material of a piston 10 is manufactured. Though four holes 25 are formed in the recessed part 13 inside the piston 10, and each seat metal 23 having a pin hole 24 is cast into two holes 25 on the diagonal lines, and the hole 25 is substantially closed. The remaining two holes 25 which do not have the sat metal 23 form an inlet and outlet for the cooling oil in a cooling cavity 18. Therefore, the leak of the cooling oil is prevented to the max. limit, and the deterioration of the cooling effect is prevented, and cost reduction can be realized. |
