| 摘要 |
PROBLEM TO BE SOLVED: To provide a cast product having small draft of an inner peripheral surface or an outer peripheral surface. SOLUTION: In a movable mold 226 in a metallic mold apparatus for casting, a hollow cylindrical part 280 having the tapered inner peripheral surface 304 is integrally arranged, and in a fixed mold 224, a tapered member 310 having the tapered outer peripheral surface 326 corresponding to the tapered inner peripheral surface 304, is arranged. The outer peripheral surface of the hollow cylindrical part 280 is constituted of a cavity surface 300 for forming the inner peripheral surface of a cylindrical bore 12. The tapered inner peripheral surface 304 and the tapered outer peripheral surface 326 are shrink fitted by closing the molds 224, 226 and the hollow cylindrical part 280 is widened to the diameter at the cavity 236 side with an elastic deformation. Molten metal is poured into the cavity 236 while the hollow cylindrical part 280 is keep in the elastic deformation state After solidifying the molten metal, the molds 224, 226 are opened and the elastic deformation of the hollow cylindrical part 280 is eliminated. A gap in the radius direction is formed between the outer peripheral surface of the hollow cylindrical part 280 and the inner peripheral surface of the cylinder bore 12 and then, a cylinder block 10 can easily be ejected off from the movable mold 226.
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