Abstract: A control device for an internal combustion engine comprising an EGR passage (22) for connecting an intake passage (17) and an exhaust passage (18) with each other, an EGR valve (24) provided in the EGR passage (22), and an intake throttle valve (19) provided in the intake passage (17) at an upstream side of the connection part with the EGR passage (22). The control device comprises operational state detection means for detecting an operational state of the internal combustion engine, first control means for controlling opening and closing of the intake throttle valve (19) and the EGR valve (24) to adjust intake air volume if the operational state detection means detects a normal operational state, and second control means for controlling the intake throttle valve (19) at a predetermined constant opening degree and for controlling opening and closing of the EGR valve (24) to adjust an intake air volume if the operational state detection means detects a predetermined operational state.

Abstract: An EGR control apparatus for a diesel engine which can stop EGR in advance of increase of a fuel injection quantity when acceleration of the engine comprises: EGR means (4) to adjust an EGR volume which is recirculated from an exhaust pipe (2) to an intake pipe (3); filter means (23) to carry out a smoothening-process to an accelerator opening degree detected by an accelerator opening degree sensor; injection quantity determination means (24) to determine a target fuel injection quantity to be injected from an injector (20), using the accelerator opening degree after smoothening-processed; and control means (25) to calculate a fuel injection quantity for judging EGR stop (Qcut), using the accelerator opening degree before smoothening-processed, to allow the EGR means (4) to carry out a decrease control for the EGR volume when the fuel injection quantity for judging EGR stop (Qcut) exceeds a predetermined threshold value (Hi).

Abstract: A control device for an internal combustion engine comprising an EGR passage (22) for connecting an intake passage (17) and an exhaust passage (18) with each other, an EGR valve (24) provided in the EGR passage (22), and an Intake throttle valve (19) provided in the intake passage (17) at an upstream side of the connection part with the EGR passage (22). The control device comprises operational state detection means for detecting an operational state of the internal combustion engine, first control means for controlling opening and closing of the intake throttle valve (19) and the EGR valve (24) to adjust intake air volume if the operational state detection means detects a normal operational state, and second control means for controlling the intake throttle valve (19) at a predetermined constant opening degree and for controlling opening and closing of the EGR valve (24) to adjust an intake air volume if the operational state detection means detects a predetermined operational state.

Abstract: An EGR control apparatus for a diesel engine which can stop EGR in advance of increase of a fuel injection quantity when acceleration of the engine comprises: EGR means (4) to adjust an EGR volume which is recirculated from an exhaust pipe (2) to an intake pipe (3); filter means (23) to carry out a smoothening-process to an accelerator opening degree detected by an accelerator opening degree sensor; injection quantity determination means (24) to determine a target fuel injection quantity to be injected from an injector (20), using the accelerator opening degree after smoothening-processed; and control means (25) to calculate a fuel injection quantity for judging EGR stop (Qcut), using the accelerator opening degree before smoothening-processed, to allow the EGR means (4) to carry out a decrease control for the EGR volume when the fuel injection quantity for judging EGR stop (Qcut) exceeds a predetermined threshold value (Hi).