| 摘要 |
A valve system is provided to reduce the mean effective frictional pressure in idling of the cylinder as one of two valves has fixed, relatively low lift height. A valve system comprises a first valve(325) and a second valve(330) installed in ports performing inhalation or ventilation, a first cam unit(205) formed on a cam shaft, and a second cam unit(210) located apart from the first cam unit on the cam shaft. The first cam unit moves the first valve with first and second lifts of different sizes. The second cam unit moves the first valve with a third lift.
|
