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:
At the time of reference position learning, an operation amount of an actuator is set such that intake valve phase changes to a position of most retarded angle in a region where the amount of change in intake valve phase relative to the actuator operation amount is small (S110). When the intake valve phase reaches the position of most retarded angle and the change in the intake valve phase stops (YES at S140), it is determined that the intake valve phase has reached the position of most retarded angle as the reference phase, and learning is completed. Further, in response to completion of learning, power supply to the electric motor as the actuator is stopped. Consequently, it becomes possible to reduce power consumption and to protect the apparatus at the reference position learning for ensuring accuracy in detecting valve opening/closing timing.
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:
A required valve timing change rate Vreq is calculated so as to make a deviation D between a target valve timing VTtg and an actual valve timing VT small and then a required speed difference DMCRreq between a motor 26 and a camshaft 16 is calculated on a basis of the required valve timing change rate Vreq. When the deviation D is larger than a predetermined value, a required motor speed Rmreq is calculated by adding the required speed difference DMCRreq to a camshaft speed RC and a motor control value is calculated so as to control the motor speed RM to the required motor speed Rmreq. When the deviation D is not larger than the predetermined value, the camshaft speed RC is set as the required motor speed Rmreq and the motor control value is calculated so as to control the motor speed RM to the camshaft speed RC.
摘要:
A current value of an intake valve phase calculated based on a sensor output is smoothed along the direction of time axis in accordance with a smoothing factor, whereby a phase detection value is detected. At the time of reference position learning, the smoothing factor is set to a value larger than at the time of normal control, so that the degree of smoothing in the smoothing process of phase detection value becomes smaller. Therefore, it is possible to detect more quickly that the intake valve timing has reached the reference timing at the time of reference position learning based on the phase detection value, than when a common smoothing factor is set both for the normal control and for the reference position learning.
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:
If it is necessary to rapidly change a phase of an intake camshaft and an intake VVT mechanism relatively slow in responsiveness as it is associated with an “A” bank of a V-type, 8-cylinder engine is in operation for at least a predetermined period of time, an ECU executes a program including the step of controlling intake VVT mechanisms to operate those associated with both the “A” bank and a “B” bank.
摘要:
A required valve timing change rate Vreq is calculated so as to make a deviation D between a target valve timing VTtg and an actual valve timing VT small and then a required speed difference DMCRreq between a motor 26 and a camshaft 16 is calculated on a basis of the required valve timing change rate Vreq. When the deviation D is larger than a predetermined value, a required motor speed Rmreq is calculated by adding the required speed difference DMCRreq to a camshaft speed RC and a motor control value is calculated so as to control the motor speed RM to the required motor speed Rmreq. When the deviation D is not larger than the predetermined value, the camshaft speed RC is set as the required motor speed Rmreq and the motor control value is calculated so as to control the motor speed RM to the camshaft speed RC.