Abstract: A plurality of intake air amount control devices for controlling an amount of air drawn into a combustion chamber in association with a depression stroke of an accelerator pedal are provided. Each of the intake air amount control devices responds to a change in depression stroke of the accelerator pedal after the lapse of a predetermined delay period.

Abstract: Calculation models (22, 24) for an in-cylinder air charge amount determine an estimated intake air pressure (Pe) based on an intake air flow rate (Ms), and then determine an air charge amount (Mc) from the estimated intake air pressure (Pe). A correction execution module (26) corrects, while a vehicle is traveling, the calculation model based on the relationship between the estimated intake air pressure (Pe) and a measured intake air pressure (Ps).

Abstract: A device for controlling an internal combustion engine, comprising a variable valve mechanism for varying opening areas (valve lift) or the working angles (valve-opening periods) of at least either the intake valves or the exhaust valves, wherein a pressure in the cylinder is calculated based on the opening area or the working angle of at least either the intake valve or the exhaust valve varied by the variable valve mechanism, and the internal combustion engine is controlled based on the pressure in the cylinder. Upon calculating the pressure in the cylinder based on the opening areas or the working angles of the intake and exhaust valves, it is possible to more suitably control the internal combustion engine based not only upon the peak combustion pressure in the cylinder like when a combustion pressure sensor is used but also upon a pressure in the cylinder at a moment other than the peak combustion pressure.

Abstract: A control apparatus for controlling an internal combustion engine includes a flow rate sensor that detects an intake air flow rate that represents a flow rate of air admitted into a combustion chamber of the internal combustion engine, a pressure sensor that detects a pressure of the air admitted into the combustion chamber of the internal combustion engine, a characteristic change estimation unit that estimates a characteristic change in the internal combustion engine in accordance with the intake air flow rate detected by the flow rate sensor and the intake air pressure detected by the pressure sensor, and a control unit capable of correcting a control amount of the internal combustion engine so as to compensate the characteristic change thereof in accordance with an estimation performed by the characteristic change estimation unit.

Abstract: An internal combustion engine has a variable valve actuation device for lifting an intake valve. The device is capable of changing the amount of opening of the intake valve. The device is configured to calculate a first estimated value Gao of the amount of intake air from a parameter regarding the operation state of the engine at the time of opening the intake valve; calculate a second estimated value Gac of the amount of intake air from a parameter regarding the operation state of the engine at the time of closing the intake valve; and calculate an actual amount of intake air Ga based on the first estimated value and the second estimated value.

Abstract: A device for controlling an internal combustion engine, comprising a variable valve mechanism for varying opening areas (valve lift) or the working angles (valve-opening periods) of at least either the intake valves or the exhaust valves, wherein a pressure in the cylinder is calculated based on the opening area or the working angle of at least either the intake valve or the exhaust valve varied by the variable valve mechanism, and the internal combustion engine is controlled based on the pressure in the cylinder. Upon calculating the pressure in the cylinder based on the opening areas or the working angles of the intake and exhaust valves, it is possible to more suitably control the internal combustion engine based not only upon the peak combustion pressure in the cylinder like when a combustion pressure sensor is used but also upon a pressure in the cylinder at a moment other than the peak combustion pressure.

Abstract: A device for controlling an internal combustion engine, comprising a variable valve mechanism for varying opening areas (valve lift) or the working angles (valve-opening periods) of at least either the intake valves or the exhaust valves, wherein a pressure in the cylinder is calculated based on the opening area or the working angle of at least either the intake valve or the exhaust valve varied by the variable valve mechanism, and the internal combustion engine is controlled based on the pressure in the cylinder. Upon calculating the pressure in the cylinder based on the opening areas or the working angles of the intake and exhaust valves, it is possible to more suitably control the internal combustion engine based not only upon the peak combustion pressure in the cylinder like when a combustion pressure sensor is used but also upon a pressure in the cylinder at a moment other than the peak combustion pressure.

Abstract: A plurality of intake air amount control devices for controlling an amount of air drawn into a combustion chamber in association with a depression stroke of an accelerator pedal are provided. Each of the intake air amount control devices responds to a change in depression stroke of the accelerator pedal after the lapse of a predetermined delay period.

Abstract: A failure diagnosis for a slide sensor of a variable valve mechanism is performed when a valve working angle is at a value in the initial state. The initial state is set to a valve characteristic state where the valve working angle is at the maximum value. The maximum valve working angle corresponds to the refuge running performable region in which an engine can be started and refuge running can be performed. Therefore, even when it is difficult to adjust the valve working angle using rotation of a spiral cam due to a failure in the slide sensor, the refuge running can be performed only by maintaining the initial state by maintaining control. It is thus possible to increase reliability of the refuge running in the case where a failure has occurred in the variable valve mechanism.

Abstract: An air-fuel ratio control apparatus of an internal combustion engine according to the present invention is provided with oxygen storage amount estimating means, downstream exhaust air-fuel ratio detecting means, maximum oxygen storage amount estimating means, and air-fuel ratio target setting means. The oxygen storage amount estimating means estimates an oxygen storage amount of an exhaust purifying catalyst, based on a history of an oxygen adsorption/desorption amount of the exhaust purifying catalyst located on an exhaust path. The downstream exhaust air-fuel ratio detecting means is located downstream of the exhaust purifying catalyst and detects an exhaust air-fuel ratio downstream of the exhaust purifying catalyst. The maximum oxygen storage amount estimating means estimates a maximum oxygen storage amount, based on an oxygen storage amount estimate when the exhaust air-fuel ratio detected is a predetermined air-fuel ratio.

Abstract: A plurality of intake air amount control devices for controlling an amount of air drawn into a combustion chamber in association with a depression stroke of an accelerator pedal are provided. Each of the intake air amount control devices responds to a change in depression stroke of the accelerator pedal after the lapse of a predetermined delay period.

Abstract: A control apparatus for an internal combustion engine provided with a fuel supply mechanism capable of adjusting a fuel supply amount includes a flow rate sensor that detects an intake air flow rate that represents a flow rate of air admitted into a combustion chamber of the internal combustion engine, a pressure sensor that detects a pressure of the air admitted into the combustion chamber of the internal combustion engine, a characteristic change estimation unit that estimates a characteristic change of the internal combustion engine in accordance with the intake air flow rate detected by the flow rate sensor and the intake air pressure detected by the pressure sensor, and a fuel supply mechanism control unit that controls the fuel supply mechanism. The fuel supply mechanism control unit controls the fuel supply mechanism such that the characteristic change in the internal combustion engine is compensated in accordance with an estimation performed by the characteristic change estimation unit.

Abstract: A control apparatus for controlling an internal combustion engine includes a flow rate sensor that detects an intake air flow rate that represents a flow rate of air admitted into a combustion chamber of the internal combustion engine, a pressure sensor that detects a pressure of the air admitted into the combustion chamber of the internal combustion engine, a characteristic change estimation unit that estimates a characteristic change in the internal combustion engine in accordance with the intake air flow rate detected by the flow rate sensor and the intake air pressure detected by the pressure sensor, and a control unit capable of correcting a control amount of the internal combustion engine so as to compensate the characteristic change thereof in accordance with an estimation performed by the characteristic change estimation unit.

Abstract: An intake air amount control apparatus for an internal combustion engine is provided with: an opening control mechanism and a variable valve mechanism, which control an intake air amount; an intake characteristics change mechanism for controlling the intake air amount by adjusting a parameter or parameters different from those of the above two mechanisms; and an intake amount control device for performing a cooperative control of these mechanisms upon the occurrence of any normal condition. The intake air amount control apparatus is also provided with: an abnormality detection device for detecting an abnormal condition in these three mechanisms; and a fail-safe device for controlling the intake air amount of the opening control mechanism out of these three mechanisms and controlling the other two mechanism, so as to fix their control amounts to constant values.

Abstract: An internal combustion engine has a variable valve actuation device for lifting an intake valve. The device is capable of changing the amount of opening of the intake valve. The device is configured to calculate a first estimated value Gao of the amount of intake air from a parameter regarding the operation state of the engine at the time of opening the intake valve; calculate a second estimated value Gac of the amount of intake air from a parameter regarding the operation state of the engine at the time of closing the intake valve; and calculate an actual amount of intake air Ga based on the first estimated value and the second estimated value.

Abstract: An intake air amount control apparatus for an internal combustion engine is provided with: an opening control mechanism and a variable valve mechanism, which control an intake air amount; an intake characteristics change mechanism for controlling the intake air amount by adjusting a parameter or parameters different from those of the above two mechanisms; and an intake amount control device for performing a cooperative control of these mechanisms upon the occurrence of any normal condition. The intake air amount control apparatus is also provided with: an abnormality detection device for detecting an abnormal condition in these three mechanisms; and a fail-safe device for controlling the intake air amount of the opening control mechanism out of these three mechanisms and controlling the other two mechanism, so as to fix their control amounts to constant values.

Abstract: If during a specific steady operation state of an engine, the actual intake pipe pressure is different from a target intake pipe pressure set during the specific steady operation state, a first correction amount for the throttle valve control value is calculated by causing the actual intake pipe pressure to become equal to the target intake pipe pressure. If at this time the actual amount of intake air is still different from a target amount of intake air set during the specific steady operation state, a second correction amount for the variable valve control value is calculated by causing the actual amount of intake air to become equal to the target amount of intake air. The second correction amount is used to further correct the throttle valve control value corrected by the first correction amount.

Abstract: In an estimation apparatus of an air intake flow for an internal combustion engine, an air intake flow rate fed into a portion just upstream of an intake valve at a predetermined timing before starting of fuel injection is calculated based on an output of an air flow meter. A variance in the air intake flow rate caused by the change in the intake pressure at the portion just upstream of the intake vale at the predetermined timing is calculated based on an output of a pressure sensor. The calculated air intake flow rate is added to the variance to obtain an air intake flow rate fed into a cylinder at the predetermined timing. The air intake flow rate fed into the cylinder is corrected to an air intake flow rate required for estimating an actual air intake flow based on an amount of change in the air intake flow rate fed into the cylinder at the predetermined timing.

Abstract: A control apparatus is provided for a valve actuating system which is operable to lift an intake valve or an exhaust valve of an internal combustion engine and includes a lift characteristic changing mechanism for changing a lift characteristic of the intake valve or the exhaust valve. The control apparatus calculates a target operation value of the lift characteristic changing mechanism, and calculates a realizable range of the operation value which can be realized by the lift characteristic changing mechanism, based on a controlled variable that can be given to the lift characteristic changing mechanism and at least one parameter related to an environment surrounding the lift characteristic changing mechanism. If the target operation value is not within the realizable range of the operation value, the control apparatus calculates a new target operation value to be within the realizable range.

Abstract: A control system of an internal combustion engine includes a timing changing unit that changes opening and closing timing of an intake valve relative to rotation of an output shaft of the engine, a working angle changing unit that changes a working angle of the intake valve, a throttle mechanism including a throttle valve provided in an intake passage of the engine and an actuator that is operable to open and close the throttle valve, and an intake air quantity control unit that controls the timing changing unit, the working angle changing unit and the throttle mechanism so as to control an intake air quantity of the engine to a target intake air quantity. The control system detects a failure of at least one of the timing changing unit, the working angle changing unit and the throttle mechanism, and, upon detection of a failure, executes a selected one of difference fail-safe control processes corresponding to different forms of failures, depending upon the form of the detected failure.