To provide an EGR (exhaust gas recirculation) device capable of accurately determining ON/OFF of an EGR mechanism.
When the EGR device is operated, the rotating speed of a diesel engine body 1 detected by an engine rotating speed sensor 22 is sent to an electronic control unit 3 to determine whether the engine speed Ne is within a range of N1-N2 in a step S1, and if the engine speed Ne is within this range, a shift to a step S2 is made. In the step S2, cargo lever opening γ detected by a cargo lever position sensor 31 is sent to the electronic control unit 3 to determine whether the cargo lever opening γ is γ1 or less. When the cargo lever opening γ is γ1 or less, a shift to a step S4 is made, and the EGR mechanism is turned on. when the EGR mechanism is turned on, a shift to a step S5 is made, and an EGR flow rate is determined based on a fuel injection quantity α estimated from the cargo lever opening γ.
Michiharu Soga
Hidetoshi Furukawa
Suzuki Kenchi
Kajinami order