| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a variable valve system, attaining both reduction in vibration by a decompression effect at the initial stage of cranking at the start of an engine and an increase in cranking speed by the decompression effect and a reduction effect of valve actuation system friction. <P>SOLUTION: In the step 1, it is determined whether or not an engine is in the state immediately before a complete stop, and if the state immediately before the stop is determined, in the step 2, the valve closure timing is controlled to be enough closer to the top dead center before the bottom dead center by a lift variable mechanism and an intake valve timing variable mechanism. In the step 5, after an ignition switch is determined to turn on, at the first rotation of cranking, the decompression state and reduction in friction of the valve actuation system can be attained, thereby reducing the engine vibration and improving startability. In the step 8, the closure timing of the intake valve is controlled to the timing lag side by both variable mechanisms, thereby improving the effective compression ratio to obtain favorable combustion and attain quick complete explosion. <P>COPYRIGHT: (C)2011,JPO&INPIT</p> |
