Abstract: A method for controlling an engine comprises establishing a torque correction coefficient (KA) to compensate for reducing effect of available engine torque in operating range of different excess air ratios (&lgr;) that are lower than a predetermined value (unity=1). An initial base desired in-cylinder air mass (tQacb) is determined based on a requested engine torque (tTe). A desired excess air ratio (t&lgr;) is determined. The initial base desired in-cylinder air mass (tQacb) is adjusted with at least the desired excess air ratio (t&lgr;) and the correction coefficient (KA) to generate a desired in-cylinder air mass (tQac). A desired injected fuel mass (tQf) is controlled based on the desired in-cylinder air mass (tQac) to deliver the requested engine torque (tTe) with the desired excess air ratio (t&lgr;) held accomplished.

Abstract: In a diesel engine (1) provided with an exhaust gas recirculation mechanism (9, 10), a fuel injection timing is calculated by considering a delay of air aspirated by the cylinders of the engine (1) and a delay of exhaust gas recirculation. By performing fuel injection based on this fuel injection timing, conditions of combustion in a cylinder of the engine (1) are improved.

Abstract: A diesel particulate filter 14 that traps particulate matters in an exhaust gas and a NOx trap catalyst 13 that traps NOx in the exhaust gas are disposed in an exhaust passage (10) in an internal combustion engine (1). When a regeneration timing of the diesel particulate filter (14) and one of a regeneration timing of SOx and a regeneration timing of NOx are overlapped, the diesel particulate filter regeneration is carried out first and thereafter, the SOx regeneration or the NOx regeneration is carried out.

Abstract: An air-fuel ratio control system for an internal combustion engine is comprised of an engine condition detecting unit and a control unit. The control unit is arranged to calculate a target engine torque on the basis of an engine operating condition, to calculate a target EGR ratio, a target excess air ratio and a target intake air quantity on the basis of the engine operating condition and the target engine torque, to calculate a target equivalence ratio on the basis of the target EGR ratio and the target excess air ratio, to calculate a target injection quantity on the basis of the engine operating condition and the target equivalence ratio, and to control an air-fuel ratio by bringing a real intake air quantity to the target intake air quantity and by bringing a real fuel injection quantity to the target fuel injection quantity.

Abstract: A particulate deposit amount Spm on a particulate filter disposed in an exhaust passage is estimated during a usual period different from a regeneration period of the particulate filter and during the regeneration period thereof respectively. An increase value Dpm per unit time of the Spm during the usual period is estimated based upon an engine operating condition and a total amount of the Spm is determined by integration thereof (S15, 16).

Abstract: A control unit (41) sets a target opening of a variable nozzle (53) of a turbocharger (50) according to a running condition of a diesel engine (1), and controls the opening of the variable nozzle (53) to the target opening. The control unit (41) calculates a target opening area of an exhaust gas recirculation valve (6) using the target opening of the variable nozzle (53) and a target exhaust gas recirculation amount determined according to the running condition. Control of an exhaust gas recirculation amount is performed according to the variation of turbocharging pressure by using the target opening of the variable nozzle (53) as a parameter representing the differential pressure upstream and downstream of the exhaust gas recirculation valve (6).

Abstract: A vehicle system controls a compression ignition internal combustion engine equipped with a supercharger system including a plurality of superchargers. The compression ignition internal combustion engine has an exhaust gas recirculation (EGR) system. The vehicle system determines a desired intake manifold supercharging state (tQac) and a desired EGR rate (Megr). The vehicle system includes control logics, each having a first input parameter and a second input parameter, for determining desired set points (Rvnt1 & Rvnt2) for the plurality of superchargers, respectively. The desired set points are used to control the plurality of superchargers, respectively. The vehicle system also includes control logic for determining the first input parameters in response to the desired intake manifold supercharging state. The vehicle system further includes control logic for determining the second input parameters in response to the desired EGR rate.

Abstract: In a diesel engine provided with an exhaust gas recirculation valve (6), a target exhaust gas recirculation amount determined based on the engine running condition is compared with a maximum recirculation amount of the valve (6) (S28). When the target exhaust gas recirculation amount exceeds the maximum recirculation amount, the target exhaust gas recirculation amount is limited to the maximum flowrate (S28). By maintaining the opening of the exhaust gas recirculation valve (6) at an opening corresponding to the maximum recirculation amount for a predetermined time even after the target exhaust recirculation amount has fallen below the maximum flowrate (S26), the exhaust gas recirculation amount is made to promptly follow the target amount.

Abstract: In a diesel engine (1) provided with an exhaust gas recirculation mechanism (9, 10), a fuel injection timing is calculated by considering a delay of air aspirated by the cylinders of the engine (1) and a delay of exhaust gas recirculation. By performing fuel injection based on this fuel injection timing, conditions of combustion in a cylinder of the engine (1) are improved.

Abstract: In a diesel engine provided with an exhaust gas recirculation valve (6), a target exhaust gas recirculation amount determined based on the engine running condition is compared with a maximum recirculation amount of the valve (6) (S28). When the target exhaust gas recirculation amount exceeds the maximum recirculation amount, the target exhaust gas recirculation amount is limited to the maximum flowrate (S28). By maintaining the opening of the exhaust gas recirculation valve (6) at an opening corresponding to the maximum recirculation amount for a predetermined time even after the target exhaust recirculation amount has fallen below the maximum flowrate (S26), the exhaust gas recirculation amount is made to promptly follow the target amount.

Abstract: A control unit (41) controls an opening of an exhaust recirculation valve (6) according to a running condition of a diesel engine (1). The control unit (41) calculates an equivalence ratio of the gas mixture supplied to the engine (1) and a target intake fresh air amount taking account of the air amount in the exhaust gas recirculated by the exhaust gas circulation valve (6), based on the opening of the valve (6) and a target excess air factor of the engine (1) set according to the running condition. By controlling a turbocharger (50) according to the target intake fresh air amount, and by controlling the fuel supply mechanism according to a fuel injection amount calculated from the equivalence ratio, the excess air factor of the engine (1) and an exhaust gas recirculation rate of the exhaust gas recirculation valve (6) are respectively controlled to optimum values.

Abstract: A method for controlling an engine comprises establishing a torque correction coefficient (KA) to compensate for reducing effect of available engine torque in operating range of different excess air ratios (&lgr;) that are lower than a predetermined value (unity=1). An initial base desired in-cylinder air mass (tQacb) is determined based on a requested engine torque (tTe). A desired excess air ratio (t&lgr;) is determined. The initial base desired in-cylinder air mass (tQacb) is adjusted with at least the desired excess air ratio (t&lgr;) and the correction coefficient (KA) to generate a desired in-cylinder air mass (tQac). A desired injected fuel mass (tQf) is controlled based on the desired in-cylinder air mass (tQac) to deliver the requested engine torque (tTe) with the desired excess air ratio (t&lgr;) held accomplished.

Abstract: In air-fuel ratio control apparatus and method for an internal combustion engine having an EGR valve interposed in an EGR passage between an intake manifold and an exhaust manifold, a target EGR quantity is calculated, a determination is made which of air-fuel ratio feedback controls through an EGR control and through an intake-air quantity is to be executed according to the target EGR quantity, and one of the air-fuel ratio feedback controls is selectively made according to a result of a determination of which of the air-fuel feedback controls is to be executed. During an execution of a rich spike control, the feedback control through the intake-air quantity control is unconditionally executed.

Abstract: A basic target excess air factor tLAMBDA0 and a target fresh air intake amount tQac are set base upon the operation condition of an engine (30). A target excess air factor tLAMBDA is calculated by multiplying the ratio of a real fresh air intake amount rQac as detected by a sensor (16) and the target fresh air intake amount tQac by the basic target excess air factor tLAMBDA0. A fuel injector (9) is controlled so that the amount of fuel injected thereby converges to a target fuel injection amount tQf which corresponds to the target excess air factor tLAMBDA. It is possible to prevent variation of the output torque of the engine (30) accompanying a rich spike by this control, even if the basic target excess air factor tLAMBDA0 varies abruptly, since the fuel injection amount varies in correspondence to the variation of the real fresh air intake amount rQac.

Abstract: An air-fuel ratio control system for an internal combustion engine is comprised of an engine condition detecting unit and a control unit. The control unit is arranged to calculate a target engine torque on the basis of an engine operating condition, to calculate a target EGR ratio, a target excess air ratio and a target intake air quantity on the basis of the engine operating condition and the target engine torque, to calculate a target equivalence ratio on the basis of the target EGR ratio and the target excess air ratio, to calculate a target injection quantity on the basis of the engine operating condition and the target equivalence ratio, and to control an air-fuel ratio by bringing a real intake air quantity to the target intake air quantity and by bringing a real fuel injection quantity to the target fuel injection quantity.

Abstract: A fuel injection control system is arranged to decide the execution of a pilot fuel injection based on evaluation functions indicative of degree of a pilot fuel injection demand, to decide an engine operating condition, to calculate a fuel injection quantity for each cylinder when the engine operating condition is in the predetermined low-load operating region, to calculate a pilot fuel injection quantity for each cylinder by multiplying a predetermined ratio to the fuel injection quantity in the predetermined low-load operating region and when the pilot fuel injection is executed, and to calculate a main fuel injection quantity by subtracting the pilot fuel injection quantity from the fuel injection quantity. Therefore, this arrangement enables accurate decision as to the execution of the pilot fuel injection and proper control of pilot and main fuel injection quantities.

Abstract: This invention relates to a valve timing control device for a vehicle engine (2) which performs combustion stop in a predetermined vehicle running condition. The predetermined vehicle running condition comprises, for example, engine startup, and combustion stop is performed by stopping fuel supply to the engine (2) or stopping ignition of the supplied fuel. The device comprises an actuator (51A, 52, 55, 61) which varies the timing of an intake valve of the engine (2) according to an input signal, and a microprocessor (16, 31) which outputs the signal to the actuator (51A, 52, 55, 61). The microprocessor (16, 31) is programmed to determine whether or not combustion has stopped (S80), and when combustion has stopped, control the signal so that the open/close timing of the intake valve is retarded compared to the case when combustion has not stopped (S94).

Abstract: A control unit (41) sets a target opening of a variable nozzle (53) of a turbocharger (50) according to a running condition of a diesel engine (1), and controls the opening of the variable nozzle (53) to the target opening. The control unit (41) calculates a target opening area of an exhaust gas recirculation valve (6) using the target opening of the variable nozzle (53) and a target exhaust gas recirculation amount determined according to the running condition. Control of an exhaust gas recirculation amount is performed according to the variation of turbocharging pressure by using the target opening of the variable nozzle (53) as a parameter representing the differential pressure upstream and downstream of the exhaust gas recirculation valve (6).

Abstract: In driving apparatus and method for a hybrid vehicle, a controller is provided and programmed: to calculate a target driving force [tFd], the target driving force representing a target value of a vehicular driving force; to calculate a basic target engine speed [tNinb] on the basis of tFd, the basic target engine speed representing a basic target value of the engine speed; to calculate a power generation request quantity [tWg], the power generation request quantity representing a power to be generated by the motor/generator; to calculate a basic target engine torque [tTeg] on the basis of tFd, tWg, and tNinb, the basic target engine torque representing an engine torque to be developed when an output required for a vehicular drive and for a power drive of the motor/generator is developed at tNinb; to calculate a limit torque [tTlim] during an occurrence of a power generation request on the basis of tNinb, this limit torque representing a limit torque of the eng

Abstract: At least an engine speed, an opening of an accelerator and an amount of an intake air are detected as an engine operating condition. A standard volume for injecting fuel oil is calculated on the basis of at least the engine speed and the opening of the accelerator. A target injection timing of fuel is set on the basis of the engine speed and the standard volume for injecting fuel oil. An actual fuel injection timing is detected. A standard target EGR rate is calculated on the basis of the engine speed, the amount of the intake air and the standard volume for injecting fuel oil. An amount of adjustment of a target EGR rate is calculated on the basis of the standard volume for injecting fuel oil, the target fuel injection timing and the actual fuel injection timing. A final target EGR rate is set on the basis of the standard target EGR rate and the amount of adjustment. An EGR is controlled on the basis of the final target EGR rate.