EGR CONTROLLER FOR ENGINE

摘要

PURPOSE:To prevent knocking reliably by feeding a portion of exhaust gas into the cylinder in the first half of intake stroke under heavy load of engine while distributing the exhaust gas in layer in the end gas zone further from an ignition plug during explosion stroke. CONSTITUTION:The opening 7a at the downstream end of intake path 7 is formed to direct in tangential direction of cylinder 4 thus to produce swirl K of intake air. EGR valve 20 to be driven through a negative pressure actuator A is placed in EGR path 19 for recirculating a portion of exhaust gas in exhaust path 8 into the intake path 7 thus to control the actuator A by the negative pressure to be led through a duty valve 25 into a negative pressure chamber 23. A rotary valve 28 is arranged in the downstream of EGR valve 20 in said path 19. Said valve 28 is controlled through valve timing variable mechanism 29 such that the recirculated exhaust gas will be fed to the cylinder 4 in the first half of intake stroke under heavy load of engine.