Abstract: A control device for a diesel engine includes a variable geometry supercharger with a variable supercharge pressure mechanism and an EGR valve configured to adjust an EGR gas amount. In the control device, when the diesel engine is determined to be accelerating, a maximum exhaust pressure is set such that an increased amount of an engine torque by increasing a fuel injection amount in association with acceleration is greater than an increased amount of pumping loss increased with increasing exhaust pressure due to an actuation of the variable supercharge pressure mechanism in association with acceleration. A target control variable for the variable supercharge pressure mechanism and a target control variable for the EGR valve are controlled on the basis of the maximum exhaust pressure.

Abstract: A control device for a diesel engine includes a variable geometry supercharger with a variable supercharge pressure mechanism and an EGR valve configured to adjust an EGR gas amount. In the control device, when the diesel engine is determined to be accelerating, a maximum exhaust pressure is set such that an increased amount of an engine torque by increasing a fuel injection amount in association with acceleration is greater than an increased amount of pumping loss increased with increasing exhaust pressure due to an actuation of the variable supercharge pressure mechanism in association with acceleration. A target control variable for the variable supercharge pressure mechanism and a target control variable for the EGR valve are controlled on the basis of the maximum exhaust pressure.

Abstract: An exhaust emission control device includes a first detection unit for detecting a NOx adsorption amount and an oxygen storage amount of a three-way catalyst and a NOx purification catalyst during rich spike, a second detection unit for detecting the oxygen storage amount of the three-way catalyst and the NOx purification catalyst until the output of a second air-fuel sensor becomes lean after the rich spike, and a deterioration determination unit for determining deterioration of the NOx purification catalyst based on a detected value of the first detection unit and that of the second detection unit.

Abstract: A control device of a diesel engine, including an acceleration detector including an acceleration sensor, the acceleration sensor being attached to an engine body that defines a combustion chamber, the acceleration detector configured to output a vibration acceleration, an integrator configured to integrate values corresponding to amplitudes of the vibration acceleration from a predetermined integration start timing that is at least before an ignition timing, a comparison unit configured to compare an integration value of the integrator with a predetermined ignition timing judgment level, and a real ignition timing judgment unit configured to judge a real ignition timing on the basis of a reach timing, at which the integration value has reached the ignition timing judgment level.

Abstract: An exhaust emission control device includes a NOx purification catalyst, a three-way catalyst provided upstream of the NOx purification catalyst, a first air-fuel ratio sensor provided upstream of the three-way catalyst, a second air-fuel ratio provided downstream of the NOx purification catalyst, a rich spike unit for changing an exhaust gas air-fuel ratio from lean to rich for a predetermined period to reduce and purify NOx adsorbed by the NOx purification catalyst, a first detection unit for detecting a NOx adsorption amount and an oxygen storage amount of the three-way catalyst and the NOx purification catalyst during rich spike, a second detection unit for detecting the oxygen storage amount of the three-way catalyst and the NOx purification catalyst until the output of the second air-fuel sensor becomes lean after the rich spike, and a deterioration determination unit for determining deterioration of the NOx purification catalyst based on a detected value of the first detection unit and that of the seco

Abstract: A NOx trapping catalytic converter diagnostic apparatus basically has a particulate matter accumulation estimating component, a particulate matter accumulation detecting component and a deterioration determining component. The particulate matter accumulation estimating component is configured to estimate an estimated amount of particulate matter accumulated a particulate matter filter that is positioned downstream of a NOx trapping catalytic converter. The particulate matter accumulation detecting component is configured to detect a detected amount of particulate matter accumulated in the particulate matter filter. The deterioration determining component is configured to determine if deterioration of the NOx trapping catalytic converter has occurred based on the estimated amount of accumulated particulate matter and the detected amount of accumulated particulate matter without using a NOx sensor to determine if the NOx trapping catalytic converter has deteriorated.

Abstract: A control device of a diesel engine, including an acceleration detector including an acceleration sensor, the acceleration sensor being attached to an engine body that defines a combustion chamber, the acceleration detector configured to output a vibration acceleration, an integrator configured to integrate values corresponding to amplitudes of the vibration acceleration from a predetermined integration start timing that is at least before an ignition timing, a comparison unit configured to compare an integration value of the integrator with a predetermined ignition timing judgment level, and a real ignition timing judgment unit configured to judge a real ignition timing on the basis of a reach timing, at which the integration value has reached the ignition timing judgment level.

Abstract: The exhaust gas temperature control method includes executing an exhaust gas temperature control to raise an exhaust gas temperature upon determining that a purificatory performance of an exhaust gas purification device of an engine has declined. The step of executing of the exhaust gas temperature control includes performing a first fuel injection control in which a timing of a main fuel injection is retarded and a post fuel injection is executed after the main fuel injection when the internal combustion engine is operating in the first operating region, and performing a second fuel injection control in which the timing of the main fuel injection is retarded and an execution of the post fuel injection after the main fuel injection is prohibited when the internal combustion engine is operating in the second operating region.

Abstract: A diesel particulate filter (14) which traps particulate matter and a NOx trap catalyst (13) which traps nitrogen oxides are installed in series in an exhaust passage (10) of a diesel engine (1). A controller (21) calculates a particulate matter deposition amount in the diesel particulate filter (14) (S4). The controller (21), when the particulate matter deposition amount exceeds a first predetermined amount (PM2), prevents sharp increase of the particulate matter deposition amount by prohibiting rich spike where the oxygen concentration of the exhaust gas is controlled to a value corresponding to a rich air-fuel ratio in order to regenerate the NOx trap catalyst (13) (S301, S302, S306), and prevents the particulate matter deposition amount of the diesel particulate filter (14) from reaching a limit.

Abstract: A NOx trapping catalytic converter diagnostic apparatus basically has a particulate matter accumulation estimating component, a particulate matter accumulation detecting component and a deterioration determining component. The particulate matter accumulation estimating component is configured to estimate an estimated amount of particulate matter accumulated a particulate matter filter that is positioned downstream of a NOx trapping catalytic converter. The particulate matter accumulation detecting component is configured to detect a detected amount of particulate matter accumulated in the particulate matter filter. The deterioration determining component is configured to determine if deterioration of the NOx trapping catalytic converter has occurred based on the estimated amount of accumulated particulate matter and the detected amount of accumulated particulate matter without using a NOx sensor to determine if the NOx trapping catalytic converter has deteriorated.

Abstract: The exhaust gas temperature control method includes executing an exhaust gas temperature control to raise an exhaust gas temperature upon determining that a purificatory performance of an exhaust gas purification device of an engine has declined. The step of executing of the exhaust gas temperature control includes performing a first fuel injection control in which a timing of a main fuel injection is retarded and a post fuel injection is executed after the main fuel injection when the internal combustion engine is operating in the first operating region, and performing a second fuel injection control in which the timing of the main fuel injection is retarded and an execution of the post fuel injection after the main fuel injection is prohibited when the internal combustion engine is operating in the second operating region.

Abstract: In order to prevent the generation of surge noise or other abnormal phenomena during deceleration of a vehicle, the present engine control apparatus comprises a turbo-supercharger driven by exhaust energy of the engine, at least one of an NOx trap catalyzer and a DPF mounted in the exhaust path of the engine for purifying the exhaust, an EGR path interconnecting the exhaust path and the inlet path of the engine, an EGR valve for adjusting the cross-section of the duct of the EGR path, means for detecting deceleration, and a fuel cutoff control means that, if predetermined conditions are satisfied, effects fuel cutoff control to reduces the rate of fuel injection, wherein the EGR valve is closed during the period of vehicle deceleration.

Abstract: A combustion control apparatus for an internal combustion engine having an exhaust gas purifier in an exhaust passage, includes a controller that controls supply of fuel and air to the engine. The controller is configured to produce preliminary combustion at or near compression top dead center and main combustion after an end of the preliminary combustion under a predetermined condition based on a condition of the exhaust gas purifier. The controller is further configured to determine a target intake air quantity by adding an increase correction to the target intake air quantity based on a torque correction value and determine a target fuel injection quantity by calculating the target fuel injection quantity from an actual air quantity and a target air/fuel ratio. A combustion control method is also provided.

Abstract: A diesel particulate filter (14) which traps particulate matter and a NOx trap catalyst (13) which traps nitrogen oxides are installed in series in an exhaust passage (10) of a diesel engine (1). A controller (21) calculates a particulate matter deposition amount in the diesel particulate filter (14) (S4). The controller (21), when the particulate matter deposition amount exceeds a first predetermined amount (PM2), prevents sharp increase of the particulate matter deposition amount by prohibiting rich spike where the oxygen concentration of the exhaust gas is controlled to a value corresponding to a rich air-fuel ratio in order to regenerate the NOx trap catalyst (13) (S301, S302, S306), and prevents the particulate matter deposition amount of the diesel particulate filter (14) from reaching a limit.

Abstract: In order to prevent the generation of surge noise or other abnormal phenomena during deceleration of a vehicle, the present engine control apparatus comprises a turbo-supercharger driven by exhaust energy of the engine, at least one of an NOx trap catalyzer and a DPF mounted in the exhaust path of the engine for purifying the exhaust, an EGR path interconnecting the exhaust path and the inlet path of the engine, an EGR valve for adjusting the cross-section of the duct of the EGR path, means for detecting deceleration, and a fuel cutoff control means that, if predetermined conditions are satisfied, effects fuel cutoff control to reduces the rate of fuel injection, wherein the EGR valve is closed during the period of vehicle deceleration.

Abstract: A combustion control apparatus for an internal combustion engine having an exhaust gas purifier in an exhaust passage, includes a controller that controls supply of fuel and air to the engine. The controller is configured to produce preliminary combustion at or near compression top dead center and main combustion after an end of the preliminary combustion under a predetermined condition based on a condition of the exhaust gas purifier. The controller is further configured to determine a target intake air quantity by adding an increase correction to the target intake air quantity based on a torque correction value and determine a target fuel injection quantity by calculating the target fuel injection quantity from an actual air quantity and a target air/fuel ratio. A combustion control method is also provided.

Abstract: A method of determining a degree of oil degradation in the diesel engine depending on an injection end point in such an injection way as to cause the injection 0end point to be earlier that a specific point (TB) and depending on the injection amount after the specific point and the injection end point in such an injection way as to cause the injection end point to be later than the specific point. In every fuel injection, it is judged whether the injection end point is set before or after the specific point, and a current injection degradation value is obtained by using a corresponding map. A cumulative added value is obtained to judge the oil degradation.

Abstract: It is checked whether or not a supercharged pressure Pb becomes equal to or greater than a predetermined value P0 to judge whether or not a mechanism for adjusting the supercharged pressure is failed. When it is judged that the mechanism for adjusting the supercharged pressure is not failed, the fuel injection quantity Tp of normal time is computed based upon the engine operation condition. When it is judged that the mechanism for adjusting the supercharged pressure is failed, on the other hand, the fuel injection quantity Tp of failed time is computed, which is smaller than the fuel injection quantity of normal time. The fuel injection is then controlled based upon either the computed fuel injection quantity Tp of normal time or the computed fuel injection quantity Tp of failed time.

Abstract: The oil of a diesel engine is exchanged for each running at a predetermined distance. The oil exchange is carried out by estimating the amount of soot generation by combustion based on a running distance, and is not very accurate. The oil is exchanged earlier. Therefore, the oil is consumed wastefully and a cost of maintenance is increased.

Abstract: The present invention relates to a fuel injection amount control system for a diesel engine to control a fuel injection amount electrically by an electronic-hydraulic governor. In the invention, when a driver steps on the accelerator at 100% in acceleration to raise the engine speed suddenly and vigorously, a DC linear motor transfers a control rack to the full-rack position according to the engine speed to bring the necessary amount of fuel injection. The process is that the rack position detects the second rack position firstly and the control rack leaves the second rack position accordingly, then the DC linear motor suspends the control rack at the first rack position for a certain time under a signal, afterwards and the control rack is positioned to the full-rack position by another command given to the DC linear motor to operate again.