| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a valve control system for an exhaust turbo charged internal combustion engine capable of preventing counter-flow of residual gas into a cylinder at the time of transient operation such as start acceleration to thereby improve knocking resistance and charging efficiency, resulting in an output increase. SOLUTION: This internal combustion engine comprises a variable valve control mechanism which varies opening and closing timing of an intake valve 2 or an exhaust valve 4 by continuous variable control of operating angles. At the time of idling, the engine is controlled to reduce overlap of the valves 2, 4. A transient operating condition, for example, during start acceleration, is detected from a pressure difference between a boost pressure sensor 3 and an exhaust pressure sensor 6. When the transient operating condition is detected, the overlap of the valves 2, 4 is controlled to be smaller than a set value in a steady driving mode where an operating condition is under a constant load and a constant engine speed.</p> |
