PRODUCTION OF PISTON FOR INTERNAL-COMBUSTION ENGINE

摘要

PURPOSE:To support surely a meltable core and to improve the positioning accuracy of a cooling cavity in the stage of forming the cooling cavity to the head part of a piston by supporting the meltable core by the core of dies at the two points in the direction intersecting orthogonally with the axial line of the piston. CONSTITUTION:The meltable core 21 is supported by the core of the dies at the two poins in the direction intersecting approximately orthogonally with the axial direction of a piston pin 22. The core 21 is thus made supportable by a center core 16 and the movement of said cores 17 is not hampered even in the case of casting the piston 23 by using the core of the splitable dies constituted of the center core 16 and a pair of the side cores 17 on both sides thereof. The supporing pin 20 of the core 21 is made to have the elliptical sectional shape larger in the circumferential direction of the piston 23 and smaller in the radial direction, by which the core 21 is surely supported.