Patent ID: 7685978

Claim:
A control device for a variable valve mechanism comprising: a drive element, provided in the variable valve mechanism, that determines a lift of at least one of an intake valve and an exhaust valve in an internal combustion engine; an electric actuator that adjusts a duration that represents a period in which the at least one of the intake valve and the exhaust valve is held open in terms of crank angle by moving the drive element in a variable valve control, and that is configured to maintain the drive element at a position after a supply of electric power to the actuator is interrupted, the position corresponding to a position of the drive element immediately before the supply of electric power to the actuator is interrupted; a first sensor that detects the duration; a second sensor used to determine whether the actuator will overheat; and a control unit that, when the control unit determines that the actuator will overheat based on an output from the second sensor, controls the supply of electric power to the actuator to maintain operation of the drive element under conditions corresponding to conditions prior to the determination that the actuator will overheat until the duration detected by the first sensor becomes equal to or larger than a target value, controls the supply of electric power to the actuator to maintain the duration at the target value when the duration is equal to or larger than the target value, and interrupts the supply of electric power to the actuator to maintain the position of the drive element after the control unit determines that the duration is maintained at the target value.