Abstract: An engine control apparatus having a unit for calculating the mean value of the angular acceleration with respect to each cylinder; a unit for calculating the variance of the angular acceleration with respect to each cylinder; a unit for estimating the torque and the air/fuel ratio with respect to each cylinder on the basis of the mean value and the variance; and a unit for controlling at least one of the intake air amount, the fuel injection amount and the ignition timing with respect to each cylinder on the basis of the estimated torque and air/fuel ratio.

Abstract: Provided is a control device for an engine which is capable of purifying NOx with high efficiency at a restart after an idle stop without deteriorating purification efficiency of HC and CO. At the restart after the idle stop, an air-fuel ratio is controlled to be rich, and an atmosphere inside of a catalyst is estimated on the basis of a required time ?T from a time point at which an output value (VO2—2) of first oxygen concentration detection means upstream of the catalyst exceeds a predetermined value A1 to a time point at which an output value (VO2—2) of second oxygen concentration detection means downstream of the catalyst exceeds a predetermined value A2, whereby an air-fuel ratio at next and subsequent restarts is corrected so that the atmosphere inside of the catalyst is optimized at the next and subsequent restarts.

Abstract: An EGR flow rate control apparatus of an internal combustion engine is provided that can correct with high accuracy an EGR gas flow rate measured by a gas flow rate measurement apparatus in an EGR passage and control with high accuracy a gas flow rate regulating valve to reduce discharge amounts of PM and NOx in exhaust gases. An EGR flow rate control apparatus 10 of an internal combustion engine includes a gas flow rate correction unit 45 that corrects the EGR gas flow rate based on a first operating state parameter relating to pressure fluctuations of the intake pipe or exhaust pipe of the internal combustion engine and a second operating state parameter relating to a flow channel resistance of the EGR flow channel.

Abstract: The present invention performs correction appropriately according to errors in the fuel system and air system respectively and corrects both variations in the air-fuel ratio and torque. When the difference between a target air-fuel ratio and a real air-fuel ratio is equal to or below a predetermined value when feedback control based on the air-fuel ratio of an exhaust manifold 10A is in progress, the air-fuel ratio of a cylinder cyl—1 having the largest variation of angular acceleration is corrected to the rich side, for example, by increasing the amount of fuel. Angular acceleration per cylinder is then detected again and when the variation in angular acceleration among cylinders is not eliminated, it is judged that there is an error in the amount of air control of the cylinder having the largest variation and the amount of air, amount of fuel, ignition timing or the like are corrected.

Abstract: Provided is a control apparatus for a multi-cylinder internal combustion engine equipped with fuel injection valves provided respectively for the cylinders including: a revolution measuring means for measuring a revolution speed for a predetermined angle for each cylinder; an inter-cylinder revolution-difference calculating means for calculating, from the measured revolution speed, a difference in revolution speed between a cylinder of current explosion and a cylinder of the previous explosion; an injection amount correcting means for adjusting the average amount of injection of the fuel injection valves of all the cylinders in accordance with the inter-cylinder differences in revolution speed after the cold start of the engine calculated by the inter-cylinder revolution-difference calculating means; an inter-cylinder revolution-difference averaging means for averaging the differences in revolution speed, calculated by the inter-cylinder revolution-difference calculating means, each between the cylinder of cu

Abstract: An engine controller capable of optimizing both the air-fuel ratio and the ignition timing to provide HC-minimized performance under the relevant driving conditions (environmental conditions) in order to minimize the amount of HC emitted from an engine at the time of start-up (before catalyst activation) is provided. The engine controller includes: air-fuel ratio control means for controlling the air-fuel ratio to be within a predetermined range (for example, 14.5 to 16.5) when the engine is operated at a certain driving condition (for example, in a state in which the catalyst is not activated such as the time of starting a cooler, or idling time); and ignition timing correction means for correcting the ignition timing to the retard side when the engine is operated at the certain driving condition and the air-fuel ratio is within the predetermined range.

Abstract: Provided is a control device for an engine which is capable of purifying NOx with high efficiency at a restart after an idle stop without deteriorating purification efficiency of HC and CO. At the restart after the idle stop, an air-fuel ratio is controlled to be rich, and an atmosphere inside of a catalyst is estimated on the basis of a required time ?T from a time point at which an output value (VO2—2) of first oxygen concentration detection means upstream of the catalyst exceeds a predetermined value A1 to a time point at which an output value (VO2—2) of second oxygen concentration detection means downstream of the catalyst exceeds a predetermined value A2, whereby an air-fuel ratio at next and subsequent restarts is corrected so that the atmosphere inside of the catalyst is optimized at the next and subsequent restarts.

Abstract: A control apparatus for an engine including a unit for retarding an ignition timing from an MBT by a predetermined value or more during cranking at engine starting or during a period from a first combustion up to an idling engine speed.

Abstract: An engine control apparatus having a unit for calculating the mean value of the angular acceleration with respect to each cylinder; a unit for calculating the variance of the angular acceleration with respect to each cylinder; a unit for estimating the torque and the air/fuel ratio with respect to each cylinder on the basis of the mean value and the variance; and a unit for controlling at least one of the intake air amount, the fuel injection amount and the ignition timing with respect to each cylinder on the basis of the estimated torque and air/fuel ratio.

Abstract: The present invention performs correction appropriately according to errors in the fuel system and air system respectively and corrects both variations in the air-fuel ratio and torque. When the difference between a target air-fuel ratio and a real air-fuel ratio is equal to or below a predetermined value when feedback control based on the air-fuel ratio of an exhaust manifold 10A is in progress, the air-fuel ratio of a cylinder cyl_1 having the largest variation of angular acceleration is corrected to the rich side, for example, by increasing the amount of fuel. Angular acceleration per cylinder is then detected again and when the variation in angular acceleration among cylinders is not eliminated, it is judged that there is an error in the amount of air control of the cylinder having the largest variation and the amount of air, amount of fuel, ignition timing or the like are corrected.

Abstract: An EGR flow rate control apparatus of an internal combustion engine is provided that can correct with high accuracy an EGR gas flow rate measured by a gas flow rate measurement apparatus in an EGR passage and control with high accuracy a gas flow rate regulating valve to reduce discharge amounts of PM and NOx in exhaust gases. An EGR flow rate control apparatus 10 of an internal combustion engine includes EGR flow channels 16, 20 that communicate exhaust pipe 11 with intake pipe 7, gas flow rate regulating valve 17 installed in EGR flow channels 26, 20 that regulates an EGR gas flow rate, and gas flow rate measurement apparatus 18 that is installed on an intake pipe 7 side with respect to the flow rate regulating valve 17 of EGR flow channels 16 and 20 and that measures an EGR gas flow rate flowing through the EGR flow channels 16 and 20.

Abstract: An engine control system for an internal combustion engine with a fuel injector, comprises a combustion fuel quantity computing means for computing a combustion fuel quantity in a combustion cycle; and a residual fuel quantity computing means for computing a residual fuel quantity in the combustion cycle based on a difference between an injection fuel quantity of the fuel injector and the combustion fuel quantity.

Abstract: An engine control apparatus for controlling the amount of the air flowing into each cylinder in accordance with the amount of the fuel flowing into the cylinder at the time of starting the engine is disclosed. Further, at the engine starting time, the target amount of the air flowing into the cylinder is calculated and/or the amount of the air flowing into the cylinder is controlled, based on the amount of the fuel flowing into the cylinder. The amount of the fuel remaining in the neighborhood of the engine intake port or in the intake pipe is calculated by being separated into a balanced liquid film amount and unbalanced liquid film amount. Based on the unbalanced liquid film amount, the injection fuel amount is corrected so that the amount of the fuel flowing into the cylinder is controlled with high accuracy.

Abstract: An engine controller comprises a combustion state detection or estimation means for detecting or estimating a combustion state in the combustion chamber, a combustion air-fuel ratio estimation means for estimating a combustion air-fuel ratio in the combustion chamber according to an exhaust air-fuel ratio and the detected or estimated combustion state, and a means for calculating engine control parameters according to the estimated combustion air-fuel ratio.

Abstract: An engine controller capable of optimizing both the air-fuel ratio and the ignition timing to provide HC-minimized performance under the relevant driving conditions (environmental conditions) in order to minimize the amount of HC emitted from an engine at the time of start-up (before catalyst activation) is provided. The engine controller includes: air-fuel ratio control means for controlling the air-fuel ratio to be within a predetermined range (for example, 14.5 to 16.5) when the engine is operated at a certain driving condition (for example, in a state in which the catalyst is not activated such as the time of starting a cooler, or idling time); and ignition timing correction means for correcting the ignition timing to the retard side when the engine is operated at the certain driving condition and the air-fuel ratio is within the predetermined range.

Abstract: Provided is a control apparatus for a multi-cylinder internal combustion engine equipped with fuel injection valves provided respectively for the cylinders including: a revolution measuring means for measuring a revolution speed for a predetermined angle for each cylinder; an inter-cylinder revolution-difference calculating means for calculating, from the measured revolution speed, a difference in revolution speed between a cylinder of current explosion and a cylinder of the previous explosion; an injection amount correcting means for adjusting the average amount of injection of the fuel injection valves of all the cylinders in accordance with the inter-cylinder differences in revolution speed after the cold start of the engine calculated by the inter-cylinder revolution-difference calculating means; an inter-cylinder revolution-difference averaging means for averaging the differences in revolution speed, calculated by the inter-cylinder revolution-difference calculating means, each between the cylinder of cu

Abstract: Exhaust emission control is exercised to restrict the exhaust amounts [g] of HC, CO, NOx, and the like. However, since the intake air amount for startup unduly increases due to an engine speed overshoot for startup, the exhaust amounts of HC, CO, and NOx increase excessively. Therefore, there is a need for optimizing the intake air amount for startup. The present invention proposes an engine startup control method that assures excellent startability and low exhaust emissions (small gas amount). Disclosed is an engine control device for starting an engine (from its stop state). The engine control device includes a section for setting a target engine operating state of each combustion; a section for detecting an actual engine operating state of each combustion; and a section for computing a control parameter for each subsequent combustion in accordance with the target engine operating state of each combustion and the actual engine operating state of each combustion.

Abstract: A control apparatus for an engine including a unit for retarding an ignition timing from an MBT by a predetermined value or more during cranking at engine starting or during a period from a first combustion up to an idling engine speed.

Abstract: An engine control apparatus for controlling the amount of the air flowing into each cylinder in accordance with the amount of the fuel flowing into the cylinder at the time of starting the engine is disclosed. Further, at the engine starting time, the target amount of the air flowing into the cylinder is calculated and/or the amount of the air flowing into the cylinder is controlled, based on the amount of the fuel flowing into the cylinder. The amount of the fuel remaining in the neighborhood of the engine intake port or in the intake pipe is calculated by being separated into a balanced liquid film amount and unbalanced liquid film amount. Based on the unbalanced liquid film amount, the injection fuel amount is corrected so that the amount of the fuel flowing into the cylinder is controlled with high accuracy.

Abstract: An engine control apparatus which can ensure and maintain a stability and constant exhaust emission characteristics even in such a condition that a nature of a fuel used as present is unsure, and which is robust among different fuel natures, comprising a plurality of different nature fuel quantity computing means and an operating condition detecting means for detecting an operating condition of an engine, wherein a first nature fuel quantity computing means among the plurality of different nature fuel quantity computing means is used as a fuel quantity computing means during an engine start, and the first nature fuel quantity computing means is forcibly changed over into a second nature fuel quantity computing means if an engine operating condition detected by the operating condition detecting means satisfies a predetermined term.