| 摘要 |
PURPOSE:To form efficiently molding surfaces having no positional deviation by opening communicating holes in a perpendicular state to a top mold and a bottom mold which are kept connected to each other, and centering the respective molding surfaces on the basis of the guide pins embedded in the communicating holes. CONSTITUTION:Communicating holes 13 are perpendicularly opened through a top mold 1a, circular columns 2 and a bottom mold 1b, with the respective guide holes of a casting as a center. The columns 2 are respectively cut at the bottom surface of the mold 1a and the top surface of the mold 1b to separate the mold 1a and the mold 1b. Guide pins are embedded respectively in the holes 13 of the separated mold 1a and the mold 1b in such a way that the sharpened tips of the guide pins project slightly from the molding surfaces of the mold 1a and the mold 1b. Desired coordinates are drawn on the molding surfaces of the mold 1a and the mold 1b by suitable ruling with the sharpened tip of each guide pin as a reference point. The centering of a recess 3 is performed in the mold 1a and the centering of a projecting part 4 in the mold 1b by using these coordinates and the molds are subjected to working such as cutting and grinding, etc. of a machining allowance, by which the molds are worked with high accuracy. |
