Abstract: In a valve timing control apparatus employing two lock pins located in a vane rotor and two lock holes located in a sprocket so as to permit movement of the lock pins into and out of engagement with the respective holes, a guide mechanism is provided for guiding movement of the vane rotor relative to the sprocket toward a prescribed lock position. The guide mechanism includes a guide pin and a guide hole configured to permit movement of the guide pin into and out of engagement with the guide hole. Hydraulic pressure, used for retreating-movement of the lock pins out of engagement, is supplied through a first branch passage branching from an unlock passage configured to communicate with a pump discharge passage. Hydraulic pressure, used for retreating-movement of the guide pin out of engagement, is supplied through a second branch passage branching from the same unlock passage.

Abstract: In a valve timing control apparatus employing two lock pins located in a vane rotor and two lock holes located in a sprocket so as to permit movement of the lock pins into and out of engagement with the respective holes, a guide mechanism is provided for guiding movement of the vane rotor relative to the sprocket toward a prescribed lock position. The guide mechanism includes a guide pin and a guide hole configured to permit movement of the guide pin into and out of engagement with the guide hole. Hydraulic pressure, used for retreating-movement of the lock pins out of engagement, is supplied through a first branch passage branching from an unlock passage configured to communicate with a pump discharge passage. Hydraulic pressure, used for retreating-movement of the guide pin out of engagement, is supplied through a second branch passage branching from the same unlock passage.