| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an outboard motor designed to reduce the noise transmitted to the outside. <P>SOLUTION: An extension case (20) is provided as a member composing a frame of the outboard motor. The natural vibration frequency of the extension case (20) is set to be a higher value than the vibration frequency generated when an engine (16) is operated at maximum speed to prevent the extension case (20) from being vibrated resonantly in operation of the outboard motor (10), and the noise (the noise emitted from the outboard motor (10)) transmitted to the outside is reduced. <P>COPYRIGHT: (C)2006,JPO&NCIPI |
