| 摘要 |
<p>A valve operating system in an internal combustion engine includes a cam shaft provided with a valve operating cam, a rocker arm having first and second support walls opposed to each other at a distance, a support shaft mounted to extend between the support walls, a roller rollably supported on the support shaft through a bearing, and an urging means for urging the rocker arm in a direction to bring the roller into rolling contact with the valve operating cam. In the valve operating system, one of the support walls included in the rocker arm is integrally provided with a receiving portion which contacts with the urging means. Thus, the structure of the rocker arm can be simplified in such a manner that the receiving portion is positioned to the side of the roller; and an increase in size of the rocker arm can be avoided and further, the inertial weight is reduced. Therefore, it is possible to conveniently accommodate the high-speed rotation of the internal combustion engine.</p> |
