摘要 |
A valve driving system for an internal combustion engine having two intake valves and/or two exhaust valves for each cylinder, which includes a cam shaft formed with a pair of low speed cams and a high speed cam located at substantially the center part of the cam shaft, a pair of first rocker arms driven by the low speed cams respectively, each having a portion engaged with one of the valves, second rocker arms driven by the high speed cam and located between the first rocker arms, two oil pressure chambers formed in the second rocker arm and facing the respective first rocker arms, two plungers, each being provided in one of the oil chambers, two bores each being formed engageably with one of the plungers in one of the first rocker arms, an oil passage formed in the second rocker arm and communicated with both oil pressure chambers, and a control valve for controlling oil pressure fed to the oil passage in accordance with the engine operating condition.
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