| 摘要 |
PURPOSE:To obtain optimum valve operating characteristics and improve an output, by rockably mounting to a rocker shaft a rocker arm abutting against a low-speed cam and the upper end of a valve and a cam arm abutting against a high-speed cam, and designing to connect or disconnect both the arms. CONSTITUTION:A low-speed cam 2 and a high-speed cam 3 are mounted to a cam shaft 1. A rocker arm 4 abutting against the upper end of a valve stem at one end abuts against the low-speed cam 2 at the other end, and a cam arm 7 abuts against the high-speed cam 3. Both the arms 4 and 7 are formed with through-holes 9. In high-speed running, a pin 8 inserted into the through- hole 9 of the cam arm 7 is pushed by a push rod 13 operated by an electromag netic device 12, and is inserted into the through-hole 9 of the rocker arm 4, thereby connecting both the arms 4 and 7 and letting the rocker arm 4 follow the high-speed cam 3. Thus, the valve is driven with optimum operating characteristics according to engine speeds to thereby obtain a high output over the entire range and improve fuel consumption. |
