| 摘要 |
A pair of main molds forming an outer peripheral face of a piston and a pair of side cores forming the pair of cutout recess parts of the piston are prepared, the main mold and the side core are set so as to form a cavity corresponding to the piston, the cavity is charged with molten metal, and when the side core is moved downward and in a direction away from the central axis of the piston so as to carry out mold release from the cutout recess part after the piston within the cavity has solidified, the side core is tilted in a direction in which an upper end thereof approaches the central axis of the piston. Thus, it is possible to release a core smoothly from a cutout recess part without it biting into an inside face of the cutout recess part. |
