Abstract: When controlled variable in a variable valve event and lift mechanism is made to be a predetermined value, requested closing timing at which a target air amount can be obtained and requested opening timing at which a target residual gas rate can be obtained are calculated, and the controlled variable is changed in stepwise until an absolute value of a deviation between a requested operating angle at the requested closing timing and the requested opening timing, and an operating angle corresponding to the controlled variable, reaches a predetermined value or less, so that the controlled variable of the time when the absolute value of the deviation reaches the predetermined value or less is set to a desired value.

Abstract: A requested volume flow ratio calculated based on a requested torque, an amount of two times a spit-back gas amount at the valve overlap time calculated based on a requested residual gas rate, and a spit-back gas amount of the time when an intake valve is closed are added together, to set a requested valve passing gas amount of the intake valve, thereby determining a target operating characteristic of the intake valve based on the requested valve passing gas amount.

Abstract: In an internal combustion engine equipped with a variable valve operating mechanism that performs a valve timing control and a valve lift amount control of at least one of an intake valve and an exhaust valve, target values of the valve timing and the valve lift amount set based on an engine operating condition are limited by a limit value to limit a control range of one of the valve timing and the valve lift amount in accordance with a control state of the other of the valve timing and the valve lift amount, so that the valve timing and the valve lift amount are controlled based on the respective target values one of which has been limited as above.

Abstract: In an internal combustion engine provided with a variable valve mechanism that varies an open/close characteristic of an intake valve, a target open/close characteristic of the intake valve is determined and at the same time, a control speed of when the intake valve is controlled to have the target open/close characteristic is determined, so that the variable valve mechanism is controlled according to the target open/close characteristic and the control speed.

Abstract: A rotation phase of a camshaft relative to a crankshaft is detected based on a crank angle signal and a cam angle signal, and also the currents or voltages of electromagnetic brakes constituting a variable valve timing mechanism are converted into the rotation phase, to estimate a change in the rotation phase during the rotation phase is detected, based on the rotation phase obtained by converting the currents or voltages.

Abstract: In an internal combustion engine provided with a variable valve mechanism that varies a valve operating characteristic of an intake valve, the valve operating characteristic of the intake valve is detected, and a flow loss coefficient and an effective opening area of the intake valve are calculated based on the valve operating characteristic, to calculate an intake air flow amount in a cylinder portion based on parameters inclusive of the calculated flow loss coefficient and effective opening area.

Abstract: In a sliding mode control system to feedback control a control object amount to a target value by calculating an operation amount based on a non-linear term calculated corresponding to a switching function and a linear term, an abnormality judgment signal is output when an operation amount by the non-linear term does not change within a predetermined time from when a predetermined period of time has elapsed after the target value has changed.

Abstract: In a constitution to control a valve lift amount of an intake valve to achieve a target intake air amount, a target valve overlap amount is calculated based on an engine load and an engine rotation speed, and target valve timing is calculated based on a target valve lift amount and the target valve overlap amount, so that the valve overlap amount is maintained at a requested value corresponding to operating conditions.

Abstract: In an international combustion engine in which fuel injection valves are arranged upstream from and downstream from the throttle valve, respectively, the response of the accelerated increase in quantity and correction will be improved. The total injection quantity determination unit determines a total quantity of fuel to be injected from each fuel injection valve on the upstream and downstream sides. The injection rate determination unit determines an injection rate of the upstream injection valve. The correction factor calculation unit calculates a total correction factor. The injection quantity correction unit includes an accelerated increase in quantity and correction unit, and during acceleration, increases and corrects only the injection quantity of the downstream injection valve during acceleration.

Abstract: To enable restart of an engine by detecting that a vehicle is restored to the upright position after overturning in an early state. An acceleration sensor having a detection shaft laid laterally of a vehicle body is integrated into an ECU and mounted on the vehicle body. Outputs of the acceleration sensor are weighted and averaged, and when an average value exceeds an overturn threshold repeatedly, an overturn determination unit determines that the vehicle is overturned. On the other hand, when outputs of the acceleration sensor are determined to be below a restoration threshold, and the determination is repeatedly made, it is determined that the vehicle is restored from the overturned state. The engine is stopped when determination of overturn is made, while restart of the engine is enabled when determination of restoration is made. Especially, the reference value of determination is set so that determination of restoration is made at an early stage.

Abstract: In an internal combustion engine provided with a variable valve operating apparatus which variably changes a valve operating characteristic of at least one of intake and exhaust valves, a reference intake pipe pressure and a reference fresh air ratio corresponding to a reference operating condition of the variable valve operating apparatus are computed based on the detection value of the engine operating condition, a fresh air ratio correction amount corresponding to an operating condition of the variable valve operating apparatus is computed based on the detection value of the intake pipe pressure and the reference intake pipe pressure, the reference fresh air ratio is corrected based on the computed fresh air ratio correction amount to compute a final fresh air ratio, and an operating amount of the control object in the internal combustion engine is computed based on the final fresh air ratio to operate the control object.

Abstract: In an internal combustion engine provided with a variable valve mechanism that variably controls at least an operating characteristic (valve lift amount and the like) of an intake valve, a valve opening area AWm at a valve overlap time is calculated based on a valve lift amount (VCS-ANGL) and opening timing IVO of the intake valve, and a spit-back gas amount Wm at the valve overlap time is calculated based on the valve opening area AWm. On the other hand, a volume flow ratio (basic actual engine volume flow ratio) RQH0VEL1 in the intake valve, equivalent to an actual intake air amount of the engine, is calculated based on the valve lift amount and closing timing of the intake valve, and a basic residual gas amount Wcyl is calculated based on the basic actual engine volume flow ratio RQH0VEL1. Then, a resultant obtained by adding the spit-back gas amount Wm and the basic residual gas amount Wcyl, is set as a total residual gas amount of the engine.

Abstract: In an internal combustion engine provided with a variable valve mechanism that varies at least a valve operating characteristic (valve lift amount and the like) of an intake valve, a target intake air amount equivalent to a target torque is set based on operating conditions of the engine, to calculate a target volume flow ratio by dividing the target intake air amount by an engine rotation speed and total cylinder volume. The target volume flow ratio is corrected according to closing timing of the intake valve. If the valve lift amount of the intake valve is in a low valve lift region, the target volume flow ratio is further corrected according to the valve lift amount, and the post corrected target volume flow ratio is converted into a valve opening area of the intake valve to be set as a target valve opening area. Then, based on the target valve opening area, a target valve operating characteristic of the intake valve is set.

Abstract: To allow an engine having an intake duct for drawing running air to produce a high output by performing appropriate fuel injection depending on dynamic pressure variations. A vehicle speed corrective coefficient calculator calculates a fuel corrective coefficient KVPLS based on a vehicle speed VPLS, and a throttle corrective coefficient calculator calculates a corrective coefficient KV&thgr;TH based on a throttle opening &thgr;TH. A corrective coefficient multiplier multiplies the fuel corrective coefficient KVPLS and the corrective coefficient KV&thgr;TH, thus calculating a vehicle speed fuel adjustment corrective coefficient KVAF. An injection time calculator calculates a basic injection time TiM based on the throttle opening &thgr;TH and an engine rotational speed Ne, and also calculates a fuel injection time Ti by reading the vehicle speed fuel adjustment corrective coefficient KVAF and correcting the basic injection time TiM.

Abstract: In a variable valve mechanism that changes an opening characteristic of an engine valve by a rotation force of a direct current motor, an electric current to be supplied to the direct current motor is forcibly lowered by providing restriction to a control signal of a power transistor that supplies the electric current to the direct current motor, or providing restriction to a change speed of target value of the opening characteristic, when an engine temperature is high.

Abstract: In an electronically controlled fuel injection apparatus of a speed density type, a new air intake efficiency correction value for correcting an intake pressure is calculated based on the intake pressure, an engine rotation speed, and an advance angle amount of valve timing.

Abstract: In an internal combustion engine provided with a variable valve mechanism that varies a valve operating characteristic of an intake valve, the valve operating characteristic of the intake valve is detected, and a flow loss coefficient and an effective opening area of the intake valve are calculated based on the valve operating characteristic, to calculate an intake air flow amount in a cylinder portion based on parameters inclusive of the calculated flow loss coefficient and effective opening area.

Abstract: In a constitution to control a valve lift amount of an intake valve to achieve a target intake air amount, a target valve overlap amount is calculated based on an engine load and an engine rotation speed, and target valve timing is calculated based on a target valve lift amount and the target valve overlap amount, so that the valve overlap amount is maintained at a requested value corresponding to operating conditions.

Abstract: In an internal combustion engine provided with a variable valve mechanism that varies at least a valve operating characteristic (valve lift amount, valve operating angle and the like) of an intake valve, a target volume flow ratio equivalent to a target torque of the engine is obtained to be converted into a valve opening area, and a target valve operating characteristic of the variable valve mechanism is set based on the converted valve opening area, to control the variable valve mechanism so that an actual valve operating characteristic reaches a target valve operating angle, thereby executing with high accuracy an intake air amount control mainly by the variable valve mechanism.

Abstract: To enable accurate detection of the alternative ambient pressure when the correction of fuel supply is carried out by the used of the value of the ambient pressure substituted by the negative pressure in the inlet pipe. The difference between the calculated alternative ambient pressure and the estimated ambient pressure (offset) is set as a plurality of functions of the number of engine revolutions and the throttle opening, and stored in the area determination section with a plurality of areas divided by each offset value. In which area the condition of the engine resides is determined from the number of engine revolution and the throttle opening and the offset corresponding to the area is supplied. The calculation section calculates the calculation base value by the use of the negative pressure PB and the offset.