Valve timing control device for internal combustion engine

A valve timing control device for an internal combustion engine, comprising:

• a housing adapted to be driven by torque transmitted from a crankshaft and having a plurality of shoes formed to protrude radially inward from an inner periphery of the housing for partitioning an internal space into a plurality of working chambers;
• a vane rotor having a rotor configured to rotate relatively to the housing and a plurality of vanes fixedly connected to a camshaft together with the rotor and formed to protrude radially outward from an outer periphery of the rotor for partitioning the working chambers into phase-retard chambers and phase-advance chambers in cooperation with the shoes;
• a hydraulically-operated lock interposed between the vane rotor and the housing and structured to restrict rotary motion of the vane rotor relative to the housing;
• and
• a hydraulically-operated fluid-communication control mechanism having a communication hole formed in at least one of the plurality of vanes so as to permit fluid-communication between the phase-retard chamber and the phase-advance chamber defined by the at least one vane through the communication hole, and configured to enable switching between a communicated state of the communication hole and a fluid-communication restricted state of the communication hole,
• wherein the hydraulically-operated fluid-communication control mechanism is located at a different position from the hydraulically-operated lock in a cross-section perpendicular to an axis of the vane rotor, and a hydraulic pressure required for restricting fluid-communication by way of the communication hole by the hydraulically-operated fluid-communication control mechanism is set to be relatively less than a hydraulic pressure required for a switching operation of the hydraulically-operated lock from a lock state, in which rotary motion of the vane rotor relative to the housing is restricted, to an unlock state, in which rotary motion of the vane rotor relative to the housing is enabled.