| 摘要 |
A crankshaft 2 of an internal combustion engine 1 includes crank journals 23 adapted to be pivotally supported by a crankcase 10, crank pins 25 adapted to pivotally support connecting rods 17F and 17R, and crank webs 20 connecting the crank journals 23 and crank pins 25. Holes 3, 4 are provided in the crank webs 20, and run from the side faces of the crank webs 20 in axial view of the crankshaft 2 and pass near connection sections C between the crank pin 25 and the crank webs 20. With such a crankshaft, it is possible to reduce stress on connection sections between crank pins and crank webs by distributing stress so as to ensure rigidity of the crank webs. |
