| 摘要 |
PROBLEM TO BE SOLVED: To optimize supply/stop timing of fresh air in an internal combustion engine, in which the fresh air is supplied to the lower stream of a throttle valve from a fresh air bypass passage when the throttle valve and an EGR valve are closed and operated.SOLUTION: An EGR passage 22 is connected to an intake passage 7, as well as a fresh air bypass passage 14 is connected when a connection part of an EGR passage 22 is closed. A surge tank 12 is arranged at the lower side than the end terminal of the fresh air bypass passage 14. Closing and opening of the bypass valve 15 is controlled based on detection values of a second intake pressure sensor 27 and a surge pressure sensor 28. The bypass valve 15 can be closed by accurately grasping the timing when the remaining EGR gas 34 is completely gone. Therefore, sufficient torque deviation can be prevented, achieving smooth operation. |
