| 摘要 |
PROBLEM TO BE SOLVED: To improve the drivability of an internal combustion engine with an exhaust throttle valve and an EGR device by accurately increasing/decreasing a proper amount of fuel at a good timing during operating the exhaust throttle valve and the EGR valve. SOLUTION: An exhaust emission control device for an internal combustion engine has an exhaust throttle valve 14 closed to throttle an exhaust pipe 9b when a diesel engine 1 is in a preset operated condition, a fuel supply control means 21 to control the supply amount and timing of fuel to the diesel engine 1 when the exhaust throttle valve 14 is closed, an exhaust recirculation passage 15 via which the exhaust pipe 9b and an intake pipe 8b are connected together in a bypass form to recirculate exhaust gas from the exhaust pipe 9b to the intake pipe 8b and circulated exhaust gas amount control means 16, 20 to control the amount of exhaust gas flowing from the exhaust pipe 9b to the intake pipe 8b via the exhaust recirculatin passage 15. The fuel supply control means 21 is operated in accordance with the recirculated exhaust gas control means 16, 20 when the exhaust throttle valve 14 is operated. |
