| 摘要 |
PURPOSE:To obtain optimum valve operating characteristics and a high output over the entire range, by engaging a rocker arm with a rocker shaft by a spline, and fixing to a rocker shaft a cam arm abutting against a low-speed cam or a high-speed cam to move the rocker shaft. CONSTITUTION:A low-speed cam 2 and a high-speed cam 3 are mounted side by side to a cam shaft 1, and a cam arm 5 is fixed to a rocker shaft so as to selectively abut against either of the low-speed cam 2 or the high-speed cam 3. The rocker shaft 4 is formed with a spline 7 which is engaged with a rocker arm 8 prevented from moving along the rocker shaft by a retainer 9. An electromagnetic solenoid 12 is operated according to engine speeds to axially move the rocker shaft 4. As a result, the cam arm 5 is selectively engaged with either of the low-speed cam 2 or the high-speed cam 3. Thus, valve operating characteristics are optimumly selected according to the engine speeds, and a high output may be obtained over the entire range. Further, fuel consumption may be improved. |
