| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a method for manufacturing a crankshaft which enables a targeted shape of a molded product to be manufactured with high precision in side molding by forging. <P>SOLUTION: When there is a clearance between a premolded article 40 and the cavity of a mold 31, a molded product is obtained by filling the mold 31 with the materials of the premolded article 40, but deformation occurs in the molded product, as shown in Drawing 7 (B). In the deformation of the molded product, a journal 41 moves so as to be separated from a crank pin 43 in the direction vertical to the reference axis. In designing the premolded article, the shape of the premolded article 200 is decided on the basis of the previously obtained amount of the move of the journal 211 in the direction vertical to the reference axis from the crank pin 213, by inserting the punch P into the crank pin 213 in forging. Even if deformation occurs in the molded product due to the insertion of the punch P, the deformation can be offset. <P>COPYRIGHT: (C)2012,JPO&INPIT |
