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: A fuel injection control device includes an exhaust purification device for purifying an exhaust gas by catalytic action, an exhaust gas-temperature detection unit for detecting exhaust gas temperature, and a determination unit for determining the amount of the basic fuel injection and basic fuel injection timing from the operational status of a combustion engine, and a control unit for controlling the amount of the fuel injection and fuel injection timing. The control unit retards the fuel injection timing from the basic fuel injection timing when the exhaust gas temperature is lower than the temperature required for the catalytic activation of the exhaust purification device. The control unit also increases the amount of the fuel injection compared to the amount of the basic fuel injection to compensate for the loss of the torque output caused by the retarded fuel injection timing.

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 fuel injection quantity control device includes: vehicle speed detection unit; gear position detection unit; engine revolution speed detection unit; accelerator opening degree detection unit; target acceleration value computation unit for finding a basic target acceleration value corresponding to the difference between the set limit vehicle speed and an actual vehicle speed and an upper limit value and lower limit value of the basic target acceleration value for each gear position in a map, limiting the basic target acceleration value with the upper limit value and lower limit value, and determining a target acceleration value; basic fuel injection quantity for vehicle speed limit computation unit for determining a basic fuel injection quantity for vehicle speed limit by feedback computation from the difference between the determined target acceleration value and the actual acceleration value; an accelerator required injection quantity computation unit for computing an accelerator required injection quantit

Abstract: A fuel injection control device includes an after treatment device for purifying exhaust gas by the action of a catalyst, an exhaust gas temperature detector for detecting the exhaust gas temperature, and a controller for controlling the fuel injection quantity and fuel injection timing. The controller executes an exhaust gas temperature increase control by post-injection when the exhaust gas temperature detected by exhaust gas temperature detection means is less than the activity temperature of the catalyst in the after treatment device.

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: The common rail fuel injection control device in accordance with the present invention computes a base duty (A) equivalent to a base target opening degree of a metering valve and a correction coefficient (B) based on the engine operation state, adds the value obtained by multiplying an oscillation duty (C) which oscillates periodically by the correction coefficient (B) to the base duty (A), and determines the final duty (D) equivalent to a final target opening degree of the metering valve.

Abstract: The detected values of a common rail pressure that were detected by a pressure sensor are read within crank angle periods ?t which are at least not more than half of a pumping cycle ?T of a supply pump, the values detected within one pumping cycle preceding a reading time (for example, S(1), S(0), . . . S(?4)) are averaged during each of the reading times, and the value thus obtained (for example, Pav(1)) is used as a common rail pressure after averaging processing, which is a representative value or a control value of the actual common rail pressure. The feedback control of common rail pressure is executed by using the values of common rail pressure after averaging processing thus computed by moving averaging. Consequently, the actual common rail pressure is converted into values suitable for control, and the feedback control of common rail pressure is executed with higher accuracy.

Abstract: A fuel injection control device for executing multiple injection includes first means for determining the total injection quantity of fuel (Qtotal), second means for determining base injection quantities (QBsub) of each auxiliary injection, and third means which, when the sum (QBsubtotal) of base injection quantities (Qsub) of each of auxiliary injections is not larger than the value obtained by multiplying the total injection quantity (Qtotal) by a coefficient (K) (0<K≦1), computes the injection quantity (QTmain) of the main injection by subtracting the sum (QBsubtotal) from the total injection quantity (Qtotal), and when the sum (QBsubtotal) is larger than the value obtained by multiplying the total injection quantity (Qtotal) by the coefficient (K), computes the injection quantity (QTmain) of the main injection by reduction correcting the base injection quantities (QBsub) of auxiliary injections so that the sum (QBsubtotal′) of injection quantities (QBsub′) of auxiliary injections after t

Abstract: A fuel injection quantity control device for controlling an actual revolution speed En of an engine to a target revolution speed Eo, comprises difference computation unit for subtracting the actual revolution speed En from the target revolution speed Eo and finding the difference e therebetween; proportional term computation unit for multiplying the aforesaid difference e by the prescribed proportionality constant Kp and finding a proportional term output value Qp; integral term computation means for finding an integral term output value Qi which is obtained by integrating the product of the aforesaid difference e and the prescribed integration constant Ki; differential term computation unit for finding a differential term output value Qd which is obtained by multiplying the value obtained by differentiating the aforesaid difference e by the prescribed differentiation constant Kd; and injection quantity computation unit for adding up the proportional term output value Qp and the integral term output value Qi

Abstract: A fuel injection quantity control device includes: vehicle speed detection unit; gear position detection unit; engine revolution speed detection unit; accelerator opening degree detection unit; target acceleration value computation unit for finding a basic target acceleration value corresponding to the difference between the set limit vehicle speed and an actual vehicle speed and an upper limit value and lower limit value of the basic target acceleration value for each gear position in a map, limiting the basic target acceleration value with the upper limit value and lower limit value, and determining a target acceleration value; basic fuel injection quantity for vehicle speed limit computation unit for determining a basic fuel injection quantity for vehicle speed limit by feedback computation from the difference between the determined target acceleration value and the actual acceleration value; an accelerator required injection quantity computation unit for computing an accelerator required injection quantit

Abstract: A fuel injection quantity control device for controlling an actual revolution speed En of an engine to a target revolution speed Eo, comprises difference computation unit for subtracting the actual revolution speed En from the target revolution speed Eo and finding the difference e therebetween; proportional term computation unit for multiplying the aforesaid difference e by the prescribed proportionality constant Kp and finding a proportional term output value Qp; integral term computation means for finding an integral term output value Qi which is obtained by integrating the product of the aforesaid difference e and the prescribed integration constant Ki; differential term computation unit for finding a differential term output value Qd which is obtained by multiplying the value obtained by differentiating the aforesaid difference e by the prescribed differentiation constant Kd; and injection quantity computation unit for adding up the proportional term output value Qp and the integral term output value Qi

Abstract: A fuel injection control device includes an after treatment device for purifying exhaust gas by the action of a catalyst, an exhaust gas temperature detector for detecting the exhaust gas temperature, and a controller for controlling the fuel injection quantity and fuel injection timing. The controller executes an exhaust gas temperature increase control by post-injection when the exhaust gas temperature detected by exhaust gas temperature detection means is less than the activity temperature of the catalyst in the after treatment device.

Abstract: A fuel injection control device for executing multiple injection includes first means for determining the total injection quantity of fuel (Qtotal), second means for determining base injection quantities (QBsub) of each auxiliary injection, and third means which, when the sum (QBsubtotal) of base injection quantities (Qsub) of each of auxiliary injections is not larger than the value obtained by multiplying the total injection quantity (Qtotal) by a coefficient (K) (0<K≦1), computes the injection quantity (QTmain) of the main injection by subtracting the sum (QBsubtotal) from the total injection quantity (Qtotal), and when the sum (QBsubtotal) is larger than the value obtained by multiplying the total injection quantity (Qtotal) by the coefficient (K), computes the injection quantity (QTmain) of the main injection by reduction correcting the base injection quantities (QBsub) of auxiliary injections so that the sum (QBsubtotal′) of injection quantities (QBsub′) of auxiliary injections after t

Abstract: The common rail fuel injection control device in accordance with the present invention computes a base duty (A) equivalent to a base target opening degree of a metering valve and a correction coefficient (B) based on the engine operation state, adds the value obtained by multiplying an oscillation duty (C) which oscillates periodically by the correction coefficient (B) to the base duty (A), and determines the final duty (D) equivalent to a final target opening degree of the metering valve.

Abstract: The detected values of a common rail pressure that were detected by a pressure sensor are read within crank angle periods &Dgr;t which are at least not more than half of a pumping cycle &Dgr;T of a supply pump, the values detected within one pumping cycle preceding a reading time (for example, S(1), S(0), . . . S(−4)) are averaged during each of the reading times, and the value thus obtained (for example, Pav(1)) is used as a common rail pressure after averaging processing, which is a representative value or a control value of the actual common rail pressure. The feedback control of common rail pressure is executed by using the values of common rail pressure after averaging processing thus computed by moving averaging. Consequently, the actual common rail pressure is converted into values suitable for control, and the feedback control of common rail pressure is executed with higher accuracy.

Abstract: A fuel injection control device includes an exhaust purification device for purifying an exhaust gas by catalytic action, an exhaust gas-temperature detection unit for detecting exhaust gas temperature, and a determination unit for determining the amount of the basic fuel injection and basic fuel injection timing from the operational status of a combustion engine, and a control unit for controlling the amount of the fuel injection and fuel injection timing. The control unit retards the fuel injection timing from the basic fuel injection timing when the exhaust gas temperature is lower than the temperature required for the catalytic activation of the exhaust purification device. The control unit also increases the amount of the fuel injection compared to the amount of the basic fuel injection to compensate for the loss of the torque output caused by the retarded fuel injection timing.

Abstract: A common rail fuel injection device for ensuring the main injection start timing by correcting a pulse start time of a main injection command pulse, in accordance with the length of an interval between the main injection and a pilot injection. The recovery degree of current energy for driving an injector varies in accordance with the length of the interval Tint from a pilot injection end (T4) to an main injection start time (T6), and this variation affects the main injection start time. By taking a longer value for an injector drive delay time (Td) as the length of the interval Tint is shorter, a pulse start time (T5) of a main injection command pulse CPm for performing the main injection is corrected as a more advanced timing, and hence the fuel injection for the main injection can be performed at a prescribed injection start timing.

Abstract: When common rail pressure Pr is predetermined pressure Prai, which is low such that it is lower than the pressure for the initiation of fuel injection by the injectors (step 1), air-extraction pulse width Pwai, which is elected in accordance with a fixed value or the engine rotation speed (step 6), is elected as the final pulse width Pwf (step 7). Also, since air that is entrained with fuel is discharged at low pressure, along with fuel, from the pressure control chamber of the injectors, via a open/close valve, which opens based on pulse width Pwai, and via a discharge path, it is possible to avoid the effect, on the combustion characteristic, that arises due to the injection of entrained air, along with fuel, from nozzle holes into the combustion chamber.