| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a cylinder deactivation engine which does not require an intake and exhaust valve opening/closing stop mechanism and can improve purifying performance of a catalyst.SOLUTION: A first throttle valve 7 is arranged in a first intake passage 3 of a first cylinder 1, a second throttle valve 8 is arranged in a second intake passage 4 of a second cylinder 2, a first air-fuel ratio sensor 11 and a first catalyst 13 are arranged in a first exhaust passage 9 of the first cylinder 1, a second air-fuel ratio sensor 12 and a second catalyst 14 are arranged in a second exhaust passage 10 of the second cylinder 2, and a third air-fuel ratio sensor 15 and a third catalyst 16 are arranged in an exhaust gas confluent part 19. The first exhaust passage 9 and the second intake passage 4 are communicated with each other by an exhaust gas recirculation passage 20, and an exhaust gas recirculation valve 21 is provided in the exhaust gas recirculation passage 20. In a state that a part of the cylinders is deactivated, the second throttle valve 8 is fully closed, and exhaust gas in the first cylinder 1 is introduced into the second cylinder 2 through the exhaust gas recirculation passage 20, and an air-fuel ratio of the first cylinder 1 is controlled based on the air-fuel ratio detected by the third air-fuel ratio sensor 15.</p> |
