Abstract: Motor control means of a motor poppet valve has initial motor torque setting means for setting the initial motor torque of an electric motor so that the initial motor torque equals a torque corresponding to a force biasing a valve element of a poppet-valve body toward a valve seat or a proximate value, and drives the electric motor so as to obtain the initial motor torque when driving the electric motor to detach the valve element from the valve seat.

Abstract: An EGR control device includes an EGR control means (44) which, when a large-amount EGR is requested, continuously controls an EGR valve (26) toward a fully open condition, and then continuously controls an intake throttle valve (12) toward a fully closed condition, and in a dead region where a change in the opening of the intake throttle valve only causes a small change in EGR quantity, the control means restricts a feedback control of the EGR quantity using the intake throttle valve and performs a feedback control of the EGR quantity using the EGR valve to compensate for the restriction of the feedback control using the intake throttle valve.

Abstract: Immediately before fuel pressure is increased by a pressure-increase mechanism, a pressure-increase control valve of each cylinder is opened in timing that does not overlap the timing of opening of an injection control valve, and the period of time for which the pressure-increase control valves is opened is gradually increased. As a result, it is possible to prevent the quantity of fuel consumed by the pressure-increase mechanism from rapidly increasing when the increase of fuel pressure is started.

Abstract: Immediately before fuel pressure is increased by a pressure-increase mechanism, a pressure-increase control valve of each cylinder is opened in timing that does not overlap the timing of opening of an injection control valve, and the period of time for which the pressure-increase control valves is opened is gradually increased. As a result, it is possible to prevent the quantity of fuel consumed by the pressure-increase mechanism from rapidly increasing when the increase of fuel pressure is started.

Abstract: An exhaust emission control device of an internal combustion engine includes a fuel supply unit provided in a fuel supply passage, for supplying a reducing agent directly to a NOx trap catalytic converter; an addition pressure detection unit for detecting the supply pressure of the reducing agent supplied by the fuel supply unit; and a controller for calculating the amount of NOx adsorbed by the catalytic converter. When the supply pressure of the reducing agent is almost zero, the controller prohibits calculation of NOx adsorption amount depending on the supply of the reducing agent, creates a rich state in a cylinder, carries out calculation of NOx adsorption amount depending on the created rich state, and causes release and reduction of the adsorbed NOx.

Abstract: A failure detection apparatus for an internal combustion engine includes failure detecting means (S22–S30) for detecting abnormality of fresh air quantity detecting means (air flow sensor) based on the result of comparison between a fresh air quantity detected by the fresh air quantity detecting means (air flow sensor) and a fresh air quantity reference value set by fresh air quantity reference value setting means (S20), and a supercharger equipped with variable nozzles/vanes. The fresh air quantity reference value setting means sets the reference value (S16) in accordance with not only the operating state (engine speed Ne, fuel injection quantity Qf, etc.) of the engine but also a target vane opening set for the variable nozzles/vanes of the supercharger by target vane opening setting means (S12, S14).

Abstract: A failure detection apparatus for an internal combustion engine includes failure detecting means (S22-S30) for detecting abnormality of fresh air quantity detecting means (air flow sensor) based on the result of comparison between a fresh air quantity detected by the fresh air quantity detecting means (air flow sensor) and a fresh air quantity reference value set by fresh air quantity reference value setting means (S20), and exhaust flow rate adjusting means. The fresh air quantity reference value setting means sets the reference value (S16) in accordance with not only the operating state (engine speed Ne, fuel injection quantity Qf, etc.) of the engine but also a target adjustment amount (target throttle valve opening) set for the exhaust flow rate adjusting means by target adjustment setting means (S12, S14).

Abstract: A failure detection apparatus for an internal combustion engine includes failure detecting means (S22-S30) for detecting abnormality of fresh air quantity detecting means (air flow sensor) based on the result of comparison between a fresh air quantity detected by the fresh air quantity detecting means (air flow sensor) and a reference value for the fresh air quantity set by fresh air quantity reference value setting means (S20), and an EGR device (EGR passage, EGR valve, target opening setting means, EGR valve control means). The fresh air quantity reference value setting means sets the reference value (S16) in accordance with not only the operating state (engine speed Ne, fuel injection quantity Qf, etc.) of the engine but also a target EGR valve opening set by target opening setting means (S12, S14).

Abstract: A pressure-elevating type fuel injecting system selectively injects via injectors fuel stored in a common rail or fuel whose pressure is elevated by a pressure elevating mechanism into a combustion chamber, and comprises a crank angle sensor producing crank pulse signals in accordance with operating states of an engine, a pulse interval calculating unit calculating pulse intervals between respective crank pulse signals, and a determination unit determining the malfunction of the pressure elevating mechanism when a variation of the pulse interval is above a determination threshold.

Abstract: The present invention is a method for estimating a NOx occlusion amount of a NOx occlusion catalyst interposed in an exhaust passage in an engine, which is constituted such that a NOx occlusion amount is estimated by using a polynomial reflected with NOx occlusion characteristics of a NOx occlusion catalyst and each coefficient of the polynomial is sequentially corrected on the basis of NOx purification rates actually measured.

Abstract: A failure detection apparatus for an internal combustion engine includes failure detecting means (S22-S30) for detecting abnormality of fresh air quantity detecting means (air flow sensor) based on the result of comparison between a fresh air quantity detected by the fresh air quantity detecting means (air flow sensor) and a fresh air quantity reference value set by fresh air quantity reference value setting means (S20), and exhaust flow rate adjusting means. The fresh air quantity reference value setting means sets the reference value (S16) in accordance with not only the operating state (engine speed Ne, fuel injection quantity Qf, etc.) of the engine but also a target adjustment amount (target throttle valve opening) set for the exhaust flow rate adjusting means by target adjustment setting means (S12, S14).

Abstract: A failure detection apparatus for an internal combustion engine includes failure detecting means (S22-S30) for detecting abnormality of fresh air quantity detecting means (air flow sensor) based on the result of comparison between a fresh air quantity detected by the fresh air quantity detecting means (air flow sensor) and a fresh air quantity reference value set by fresh air quantity reference value setting means (S20), and a supercharger equipped with variable nozzles/vanes. The fresh air quantity reference value setting means sets the reference value (S16) in accordance with not only the operating state (engine speed Ne, fuel injection quantity Qf, etc.) of the engine but also a target vane opening set for the variable nozzles/vanes of the supercharger by target vane opening setting means (S12, S14).

Abstract: An accumulator type fuel injection system adapted to prevent engine trouble by making a judgement that fuel injection rate switching change-over valves provided correspondingly to fuel injection nozzles in cylinders, a valve for controlling the pressure in a low-pressure accumulator or means for detecting fuel pressures in accumulators gets out of order, and carrying out when any of these parts break down a control operation of a limp-home mode in which a region of an operation of an engine is limited. To provide such an accumulator type fuel injection system, a control means 8 is formed so that, when a judgement that first control valves 5, a second control valve 34 or pressure sensors 3a, 4a for detecting the fuel pressures in the respective accumulators get out of order is given, the control means 8 sets a discharge pressure of a fuel pump 1 not higher than a permissible pressure in a second accumulator 4, and injects a fuel from fuel injection nozzles 9.

Abstract: A pressure-elevating type fuel injecting system pressurizes high pressure fuel from a pressure accumulating chamber using a pressure-elevating mechanism and injects the pressure-elevated fuel into combustion chambers by injectors. The pressure-elevating type fuel injecting system comprises a target fuel injection quantity setting unit which sets a target fuel injection quantity, a time difference setting unit which sets a time difference between a timing for opening an injector electromagnetic valve and a timing for operating an pressure-elevating mechanism electromagnetic valve, an initial fuel injection quantity calculating unit calculating an initial fuel injection quantity on the basis of a time-dependent variation of fuel pressure and the time difference, and a final injection period setting unit which calculates an operation period of the injector electromagnetic valve, on the basis of a final fuel injection quantity and the time-dependent variation of the pressure of the pressure-elevated fuel.

Abstract: The present invention relates to an EGR control unit and EGR control method for controlling an EGR adjusting apparatus, and it is an object of the invention to calculate an EGR rate at a low cost and to control an operation of the EGR apparatus with high accuracy. The EGR control unit is made up of temperature detecting devices detect in-passage temperature at least two of an intake passage, an atmospheric air introduction passage located on the upstream side of the intake passage and communicated with the atmosphere and an EGR passage, an actual EGR rate calculating device for calculating a rate of an exhaust gas to an intake gas in an internal combustion engine on the basis of information on temperatures detected by the temperature detecting devices, and an EGR controller for controlling the EGR adjusting device through the use of the actual EGR rate calculated by the actual EGR rate calculating device.

Abstract: A failure detection apparatus for an internal combustion engine includes failure detecting means (S22-S30) for detecting abnormality of fresh air quantity detecting means (air flow sensor) based on the result of comparison between a fresh air quantity detected by the fresh air quantity detecting means (air flow sensor) and a reference value for the fresh air quantity set by fresh air quantity reference value setting means (S20), and an EGR device (EGR passage, EGR valve, target opening setting means, EGR valve control means). The fresh air quantity reference value setting means sets the reference value (S16) in accordance with not only the operating state (engine speed Ne, fuel injection quantity Qf, etc.) of the engine but also a target EGR valve opening set by target opening setting means (S12, S14).

Abstract: An ECU preliminarily obtains a target supercharging pressure determined based on an engine rotational speed and an engine load, and stores the target supercharging pressure value. The ECU commands a flow passage area changing unit to set an exhaust gas flow passage area to the maximum flow passage area or the minimum flow passage area, and judges the abnormality of a supercharger by comparing supercharging pressure detected by a supercharging pressure sensor and the stored target supercharging pressure.

Abstract: A pressure-elevating type fuel injecting system selectively injects via injectors fuel stored in a common rail or fuel whose pressure is elevated by a pressure elevating mechanism into a combustion chamber, and comprises a crank angle sensor producing crank pulse signals in accordance with operating states of an engine, a pulse interval calculating unit calculating pulse intervals between respective crank pulse signals, and a determination unit determining the malfunction of the pressure elevating mechanism when a variation of the pulse interval is above a determination threshold.

Abstract: By setting a switching timing of switching means that connects either one of a high pressure fuel source and a low pressure fuel source to an injector earlier than a point of time when an injector finishes a high pressure fuel injection, leak fuel or return fuel is reduced and an engine load is reduced and therefore mileage is improved.

Abstract: A common-rail injection system includes a first accumulator of high pressure and a second accumulator of low pressure. The common-rail injection system includes a post injection control device for injecting additional low-pressure fuel from the second accumulator through a fuel injection nozzle after main fuel is injected. The post injection control device injects the additional fuel the injection terminates at a first timing when the fuel pressure in either fuel passage or second accumulator lowers to a predetermined value lower than that of the high-pressure fuel or at a second timing when an exhaust stroke of the engine is completed, whichever earlier.