| 摘要 |
<p>PROBLEM TO BE SOLVED: To reduce noise generated from a cap which defines the inside of a crank case.SOLUTION: A change gear (20) comprises a CVT (22) which transmits a drive force of a crank shaft (21), and a crank case (24) which accommodates the CVT and the crank shaft. An accommodation chamber (46) and a crank chamber (50) of the crank case are defined by a cap (53). The CVT has a drive pulley (31) supported to the crank shaft, and is accommodated in the accommodation chamber. A drive face (36) at the cap side in the drive pulley has a sound-proof wall part (75) which is formed at an external peripheral side of an inclined part (74), and located between the cap and itself with gaps (S1, S2 and S3). The gaps are formed into shapes having bent parts (Sa, Sb) in a cross section view in the radial direction of the crank shaft.</p> |
