摘要:
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.
摘要:
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.
摘要:
A direct-fuel-injection-type internal combustion engine is equipped with an injector for injecting fuel directly into a combustion chamber of a cylinder. A controller controls the degree of opening of a throttle valve for adjusting the amount of air drawn into the combustion chamber and sets the throttle valve to a closed valve state by setting the degree of opening of the throttle valve to a degree of opening that is on the closed valve side of a post-engine start target degree of opening, when the engine is to be started. After it is determined that a start of the engine has been accomplished, the controller opens the throttle valve by gradually increasing the degree of opening of the throttle valve from the degree of opening of the closed valve state to the post-engine start target degree of opening.
摘要:
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.
摘要:
A valve timing control is executed by an ECU that controls an engine and an electric-motor ECU that controls an electric motor. The ECU and the electric-motor EDU serve different functions. The ECU sets the target phase of an intake valve based on the engine operating state, and prepares a rotational speed command value for the electric motor that serves as an actuator such that a phase feedback control loop, in which the intake valve phase is caused to match the target phase, is formed. The electric-motor EDU forms a feedback control loop for the motor speed, in which the electric power supplied to the electric motor is controlled such that the electric motor rotates in accordance with the rotational speed command value.
摘要:
An ECU transmits a pulsed operation command signal, indicating operation commands for an electric motor used as a VVT actuator, to an electric-motor EDU. The electric-motor EDU recognizes the combination of the direction in which the actuator should be operated (actuator operation direction) and the control mode based on the duty ratio of the operation command signal, and the rotational speed command value based on the frequency of the operation command signal. The electric-motor EDU controls the electric motor according to the control commands. The duty ratio indicating the combination is set such that even if the duty ratio is falsely recognized, a false recognition concerning the actuator operation direction is prevented, such false recognition causing the valve phase to change in an undesirable direction, and even if the actuator operation direction is falsely recognized, the rate of change in the phase is restricted.
摘要:
A valve timing control is executed by an ECU that controls an engine and an electric-motor ECU that controls an electric motor. The ECU and the electric-motor EDU serve different functions. The ECU sets the target phase of an intake valve based on the engine operating state, and prepares a rotational speed command value for the electric motor that serves as an actuator such that a phase feedback control loop, in which the intake valve phase is caused to match the target phase, is formed. The electric-motor EDU forms a feedback control loop for the motor speed, in which the electric power supplied to the electric motor is controlled such that the electric motor rotates in accordance with the rotational speed command value.
摘要:
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.
摘要:
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.
摘要:
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.