| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a crankshaft which prevents the occurrence of a delayed crack, has improved productivity and can be lightened. <P>SOLUTION: A peripheral part 6 of a crank pin is formed so that a value obtained by dividing the height (H) of the peripheral part 6 of the crank pin by the width (W) can be 0.4 or less (H/W≤0.4) and the difference between the maximum value (W<SB>max</SB>) and the minimum value (W<SB>min</SB>) of the width (W) of the peripheral part 6 of the crank pin can be 7 mm or less (W<SB>max</SB>-W<SB>min</SB>≤7) in the range of an angle phase -90°to an angle phase +90°when a pin top is defined as the base point 0°. Thereby, the crankshaft can avoid the delayed crack from occurring in the boundary of the fillet when the crankshaft is cooled after the fillet has been IH-treated. Accordingly, a tempering treatment can be abolished and the productivity can be improved. In addition, excessive cladding which has been conventionally necessary can be abolished and the weight of the crankshaft can be reduced. <P>COPYRIGHT: (C)2010,JPO&INPIT</p> |
