| 摘要 |
PROBLEM TO BE SOLVED: To provide a structure which does not cause eccentric wear at a thrust metal.SOLUTION: Large-diameter regions 16a, 16b which are set larger than an outside diameter dimension of a thrust metal 4 in diameter, and small-diameter regions 16c, 16d which are set smaller than the outside diameter dimension of the thrust metal 4 in diameter are arranged at a thrust metal receiving face 16 of a crankshaft 1. The large-diameter regions are arranged at a side at which a counter weight 14 is arranged and a side at which a crank arm 13 is arranged, respectively, rather than an axial line O of the crankshaft 1. Since a portion which does not normally slide-contact with the thrust metal receiving face 16 does not exists in an external peripheral portion of the thrust metal 4, an entire end face of the thrust metal 4 is substantially uniformly worn, and eccentric wear is suppressed. Furthermore, since the large-diameter regions can be formed by using a part of a material which flows into a counter weight molding part of a forging die, it is not necessary to enlarge an outside diameter dimension of a raw material before forging in advance.SELECTED DRAWING: Figure 2 |
