| 摘要 |
PURPOSE:To prevent the formation of cavity inside a cylindrical member and certainly form a cooling-water passage by securing the certain filling for the inside of the cylindrical member with the core sand by arranging the cylidrical member between the cavity of a metal mold for shaping a core after the inside of the cylindrical member is filled with the core sand. CONSTITUTION:In manufacture, a metal cylindrical member 4 is fitted into the fitting groove 3 of a core shaping metal mold 1, and the inside of the cylindrical member 4 filled with the core and 5. Then, the cavity 2 of the core metal mold 1 is filled with the core sand 5, and mold-tightening and baking are carried-out, and a cylinder block core 6 is obtained. After the core 6 is positioned into a cylinder-block main mold 7, the molten metal 8 is pressurized and poured into the part between the core 6 and the main mold 7, and casting is performed, and then the core 6 is removed to obtain the cylinder block. Since the cylindrical member 4 is set into the metal mold 1 in the state where the cylindrical member 4 is filled with the core sand 5 previously, the formation of cavity in the cylindrical member 4 can be prevented. |
