Abstract: A convergence determination of intake valve phase control is made by comparing a phase deviation of an intake valve from a target phase with a convergence determination value. At the time of convergence, it is determined that the intake valve phase has reached the target phase, so that the required phase-change amount of a camshaft is set to zero and therefore the actuator operation amount is also set to zero. At the time of engine stop when the target phase has a fixed value, after convergence of the intake valve phase control, the operation of the actuator is stopped. In addition, during the course of engine stop, the convergence determination value is set to be switched from the time of engine operation so that the convergence determination of the intake valve phase control is made in more relaxed conditions compared with at the time of engine operation.

Abstract: When an ignition switch is turned off, an ECU executes a program including the steps of: stopping an engine; setting a phase of an intake camshaft (or a phase in which an intake valve opens/closes) to be a maximally retarded phase; advancing the phase of the intake camshaft; detecting the phase of the intake camshaft as based on a number or rotations of an electric motor of an intake VVT mechanism changing the phase of the intake camshaft; and, if the phase detected as based on the number or rotations of the electric motor is advanced to a target phase, stopping changing the phase of the intake camshaft.

Abstract: In the case where an intake valve has its phase in a first region between a most retarded angle and CA(1), the rotational speed of relative rotation between an output shaft of an electric motor and a sprocket is reduced at a reduction gear ratio R(1) to change the phase of the intake valve. In the case where the intake valve has its phase in a second region between CA(2) and a most advanced angle, the rotational speed of relative rotation is reduced at a reduction gear ratio R(2) to change the phase of the intake valve. As long as the rotational direction of relative rotation is the same, the phase of the intake valve is changed in the same direction for both of the first region between the most retarded angle and CA(1) and the second region between CA(2) and the most advanced angle.

Abstract: A valve characteristic controller for an engine including variable valve actuation mechanisms, one for a first valve and another for a second valve, to vary the opening and closing timings of the valves. The controller executes main control to calculate a target timing of the first valve in accordance with an operation state of the engine and has the corresponding variable valve actuation mechanism adjust the timing of the first valve to the target timing. Further, the controller executes sub-control to calculate a target timing of the second valve based on a target valve overlap amount and the actual timing of the first valve and has the corresponding variable valve actuation mechanism adjust the valve timing of the second valve to the target timing. The main control is executed on the one of the two variable valve actuation mechanisms having a lower response speed.

Abstract: A valve characteristic controller for an engine including variable valve actuation mechanisms, one for a first valve and another for a second valve, to vary the opening and closing timings of the valves. The controller executes main control to calculate a target timing of the first valve in accordance with an operation state of the engine and has the corresponding variable valve actuation mechanism adjust the timing of the first valve to the target timing. Further, the controller executes sub-control to calculate a target timing of the second valve based on a target valve overlap amount and the actual timing of the first valve and has the corresponding variable valve actuation mechanism adjust the valve timing of the second valve to the target timing. The main control is executed on the one of the two variable valve actuation mechanisms having a lower response speed.

Abstract: An ignition timing control apparatus for an engine includes a controller that sets an ignition timing considering a change of a temperature or a pressure in a combustion chamber at a time when an opening/closing characteristic of an intake valve is changed, the opening/closing characteristic including a valve opening timing and a valve closing timing at least one of which is changed by a variable valve mechanism for the engine.

Abstract: During the period of deceleration of a vehicle, an air conditioning control unit modifies a target cooling temperature (TEO) of an evaporator to a temperature lower than that before the deceleration by ? ° C. in order to store cold in the evaporator (step S130). When the vehicle comes to rest, the air conditioning control unit sets an upwardly-modified target temperature TEOK, which is a temperature modified toward more or less higher temperatures from the target cooling temperature TEO, and brings a compressor to rest and keeps the resting state of the compressor until a detected temperature TE of an evaporator discharge temperature sensor exceeds TEOK (step S180). Therefore, it is possible to effectively utilize the cold heat stored in the evaporator 6 during the period of deceleration of the vehicle with a good feeling of passengers being maintained while the vehicle is at rest.

Abstract: In a vehicle air conditioner having a variable displacement compressor, a control unit calculates a target cooling temperature of air to be cooled by an evaporator, and controls a discharge capacity of the compressor such that a detected air temperature of the evaporator approaches the target cooling temperature. When a deceleration running state of the vehicle is detected, the control unit sets a corrected target cooling temperature lower than the target cooling temperature by a predetermined temperature, and controls the discharge capacity of the compressor such that the detected air temperature approaches the corrected target cooling temperature when the detected air temperature is lower than the corrected target cooling temperature, or controls the discharge capacity of the compressor approximately at the maximum capacity regardless of the corrected target cooling temperature when the detected air temperature is not lower than the corrected target cooling temperature.

Abstract: An controller detects a change in a load generation state of an accessory device that generates a load on the internal combustion engine during operation, and the controller in turn controls a variable valve mechanism to change at least one of an operation angle and a valve lift of an intake valve of the internal combustion engine, as well as changing an amount of an intake air drawn into the internal combustion engine, in response to the detected change in the load generation state of the accessory device.

Abstract: An ignition timing control apparatus for an engine includes a controller that sets an ignition timing considering a change of a temperature or a pressure in a combustion chamber at a time when an opening/closing characteristic of an intake valve is changed, the opening/closing characteristic including a valve opening timing and a valve closing timing at least one of which is changed by a variable valve mechanism for the engine.

Abstract: An controller detects a change in a load generation state of an accessory device that generates a load on the internal combustion engine during operation, and the controller in turn controls a variable valve mechanism to change at least one of an operation angle and a valve lift of an intake valve of the internal combustion engine, as well as changing an amount of an intake air drawn into the internal combustion engine, in response to the detected change in the load generation state of the accessory device.

Abstract: Based on results of a knock control for adjusting ignition timing in accordance with the occurrence of knocking, an electronic control unit computes deposit required ignition timing akgrg, which is ignition timing determined by taking adhesion of deposits in an internal combustion engine into consideration. Based on the deposit required ignition timing akgrg, the electronic control unit reduces a vvt allowable variable range of a target VVT advancement amount, which is a control target value of a variable valve timing mechanism. The electronic control unit corrects a required ignition timing based on the actual VVT advancement amount vt, which is chanted according to the reduction of the allowable variable range of the target VVT advancement amount. As a result, problems resulting from the adhesion of deposits are effectively avoided.

Abstract: During the period of deceleration of a vehicle, an air conditioning control unit modifies a target cooling temperature (TEO) of an evaporator to a temperature lower than that before the deceleration by ? ° C. in order to store cold in the evaporator (step S130). When the vehicle comes to rest, the air conditioning control unit sets an upwardly-modified target temperature TEOK, which is a temperature modified toward more or less higher temperatures from the target cooling temperature TEO, and brings a compressor to rest and keeps the resting state of the compressor until a detected temperature TE of an evaporator discharge temperature sensor exceeds TEOK (step S180). Therefore, it is possible to effectively utilize the cold heat stored in the evaporator 6 during the period of deceleration of the vehicle with a good feeling of passengers being maintained while the vehicle is at rest.

Abstract: In a vehicle air conditioner having a variable displacement compressor, a control unit calculates a target cooling temperature of air to be cooled by an evaporator, and controls a discharge capacity of the compressor such that a detected air temperature of the evaporator approaches the target cooling temperature. When a deceleration running state of the vehicle is detected, the control unit sets a corrected target cooling temperature lower than the target cooling temperature by a predetermined temperature, and controls the discharge capacity of the compressor such that the detected air temperature approaches the corrected target cooling temperature when the detected air temperature is lower than the corrected target cooling temperature, or controls the discharge capacity of the compressor approximately at the maximum capacity regardless of the corrected target cooling temperature when the detected air temperature is not lower than the corrected target cooling temperature.

Abstract: Based on results of a knock control for adjusting ignition timing in accordance with the occurrence of knocking, an electronic control unit computes deposit required ignition timing akgrg, which is ignition timing determined by taking adhesion of deposits in an internal combustion engine into consideration. Based on the deposit required ignition timing akgrg, the electronic control unit reduces a vvt allowable variable range of a target VVT advancement amount, which is a control target value of a variable valve timing mechanism. The electronic control unit corrects a required ignition timing based on the actual VVT advancement amount vt, which is chanted according to the reduction of the allowable variable range of the target VVT advancement amount. As a result, problems resulting from the adhesion of deposits are effectively avoided.

Abstract: The invention relates to valve condition control system and method for an internal combustion engine including a first variable valve drive mechanism for changing a valve condition of one of an intake valve and an exhaust valve, a second variable valve drive mechanism for changing a valve condition of the other of the intake valve and the exhaust valve, and a controller.

Abstract: A fuel-injected engine is operated in a compression stroke injection mode or an intake stroke injection mode. The intake flow rate appropriate for the compression stroke injection mode is greater than that of the intake stroke injection mode. When the engine is cold, the ECU determines the amount of fuel injected in accordance with the actual intake flow rate. The ECU controls a throttle valve such that the intake flow rate is appropriate for the selected fuel injection mode before the fuel injection mode is actually switched. As a result, fluctuations of the engine speed caused by switching the fuel injection mode are reduced.

Abstract: A control apparatus for a cylinder injection type internal combustion engine in which the fuel injection mode of the engine is switched between a compression stroke injection and an intake stroke injection. When the engine is cold, the compression stroke injection is selected for the fuel injection mode so that injected fuel collides with the top surface of a piston and is directed toward the vicinity of a spark plug. When the fuel injection mode is switched from the compression stroke injection to the intake stroke injection, the ignition timing is delayed during the execution of the intake stroke injection from when the fuel injection mode is switched until a predetermined period elapses compared with a case when the fuel injection mode is not switched.

Abstract: An engine has an injector, which directly injects fuel into a combustion chamber. When the coolant temperature during the cranking of the engine is low, an ECU controls the injector such that the engine is operated in a compression stroke injection mode. When the engine is operated in the compression stroke injection mode, the ECU controls the injector to advance the fuel injection timing in accordance with an increase of the coolant temperature. As a result, the engine reduces the amount of unburned discharge gas, provides improved ignition and combustion, and provides stable idling.

Abstract: The invention relates to valve condition control system and method for an internal combustion engine including a first variable valve drive mechanism for changing a valve condition of one of an intake valve and an exhaust valve, a second variable valve drive mechanism for changing a valve condition of the other of the intake valve and the exhaust valve, and a controller.