| 摘要 |
A rocker arm is provided free to pivot on a rocker shaft fixed to an engine. A valve that opens and closes according to the oscillation of this rocker arm, and a cam that causes this rocker arm to oscillate in synchronism with the engine, are also provided. A thrust fin projecting in a radial direction is formed in a one-piece construction with the rocker and is narrower than the rocker arm. A guide groove engaging with the thrust fin is formed on the engine so as to prevent the rocker arm from displacing in the axial direction of the rocker shaft. As the width of the guide groove is small, it can be formed easily and with high precision by cutting a part of the engine with an end mill.
|
