| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a control device for a compression self-ignition combustion stable even in a low operation region of an engine load.SOLUTION: In higher load side compression self-ignition combustion regions A2 and A3 than a specific engine load T1, an internal EGR is executed, and an internal EGR ratio is made higher for the lower engine load. In a low load side compression self-ignition region A1 of an engine load less than the specific load T1, an exhaust valve 22 is opened in an exhaust stroke and an intake stroke, and an intake valve 21 is so opened after the exhaust valve 22 was opened in an intake stroke as to establish a negative overlap period, for which one of the exhaust valve 22 and an intake valve 21 is closed, and the closed period EVC of the exhaust valve 22 is brought to the more advance side as the engine load is the lower.</p> |
