| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a production apparatus and a production method for a crankshaft which form a plurality of hole parts in one stroke from a top dead center to a bottom dead center of a press ram. <P>SOLUTION: Punches 112p, 117p and punches 114p, 115p are provided with two-level crossing structures 121, 122 as shown in Figs.3 and 4 in order to prevent interference between the punches in zones X, Y. In the two-level crossing structure 121, a flattened part 121B is disposed movably in a through-hole part 121A, and the punches 112p, 117p are crossed in a two-level manner. In the two-level crossing structure 122, the flattened part 121B is disposed movably in the through-hole part 121A and the punches 114p, 115p, are crossed in a two-level manner when inserted into a crank pin part 203. Thereby, the plurality of hole parts at the positions where the punches 112p, 117p and the punches 114p, 115p, are interfered with each other can be simultaneously formed. <P>COPYRIGHT: (C)2011,JPO&INPIT |
