| 摘要 |
<p>PROBLEM TO BE SOLVED: To improve starting performance at a cold time of an engine by controlling an actual compression ratio. SOLUTION: This device is provided with a variable valve gear mechanism for varying and controlling an intake valve closing timing and a variable compression ratio mechanism for varying and controlling a compression ratioε. The variable valve gear mechanism is constituted of a lift/operating angle varying mechanism capable of continuously enlarging/reducing a lift/operating angle of the intake valve and a phase varying mechanism for changing a lift center angleΦ. At an initial time of cranking, the actual compression ratio is lowered by quickening the intake valve closing timing, making the lift/ operating angle small, and cranking rotating speed is quickly raised. After the cranking rotating speed is raised, the center angleΦis lagged, the actual compression ratio is enhanced together with the high compression ratioεat the time, and an intake air temperature is raised. As a result, an initial explosion is surely led to start the engine.</p> |
