Patent ID: 7845321

Claim:
A controller for a vane-type variable valve timing adjusting mechanism in which each of a plurality of vane accommodating chambers formed in a housing is divided into an advance hydraulic chamber and a retard hydraulic chamber by a vane, a one-way valve is disposed in each of a hydraulic supply passage of the advance hydraulic chamber and a hydraulic supply passage of the retard hydraulic chamber in at least one of the vane accommodating chambers for preventing reverse flow of operating oil from the each hydraulic chamber, a drain oil passage is disposed in parallel to the hydraulic supply passage of the each hydraulic chamber for bypassing the one-way valve and a hydraulic control valve for controlling a hydraulic pressure supplied to the each hydraulic chamber includes integrally a drain switching control function for opening/closing the drain oil passage of the each hydraulic chamber, wherein: response characteristic learning means is provided for learning a response characteristic of the variable valve timing adjusting mechanism to a control current value of the hydraulic control valve.