PURPOSE: To provide a resin core with which casting with higher accuracy is possible without the possibility of erosion and deformation of the resin core in spite of contact with molten metal of a high temp. and high pressure and which is easily separable from castings.
CONSTITUTION: The resin core 2 is arranged in a cavity and the molten metal is poured into this cavity. The molten metal poured into the cavity comes into contact with stainless steel foil 6 clad on the surface of the resin core 2 and does not come into contact with a resin core body 4 and, therefore, the erosion and deformation of the resin core body 4 are surely prevented and the resin core 2 keeps surely maintaining the prescribed shape before the molten metal solidifies. The temp. of the resin core body 4 is elevated by heat even after solidification of the molten metal and the temp. at which the resin core is plasticized is attained at some point of time. The left end of the supporting part 2A of the resin core 2 is clamped by a drawing means at the point of this time and is drawn leftward. Branch parts 2B, 2C are thereby plastically deformed and the resin core is drawn from the left end of a product W and is thus separated from the product W.
OKADA MASAMICHI
SHIRAKAWA HIROICHI
TOMITAKA SHUICHI
KATO TAKAYUKI
