Patent ID: 8165784

Claim:
An apparatus for learning a reference position of a variable valve unit provided with a variable valve mechanism that varies opening characteristics of an engine valve of an engine by rotary motion of a control shaft, an actuator that generates a rotary motion of the control shaft, a stopper that is arranged to restrict the rotary motion of the control shaft, and an angle sensor that is capable of outputting signals corresponding to angle positions of the control shaft, comprising: a drive control unit that is configured, upon a condition that the engine is stopping, to control the actuator such that the rotary motion of the control shaft reaches a state where said control shaft is pressed against the stopper and then reduce drive torque of the actuator; and a learning unit that learns signals of the angle sensor, under a condition that the drive torque of the actuator is reduced by the drive control unit, as signals at a reference position where the rotary motion of the control shaft is restricted by the stopper.