Patent ID: 8689748

Claim:
A valve timing control apparatus of an internal combustion engine, comprising: a cylindrical housing having a plurality of shoes protruding radially inward from an inner peripheral surface of the housing; a vane rotor having a rotor adapted to be fixedly connected to a camshaft and a plurality of radially-extending vanes formed on an outer periphery of the rotor for partitioning a working-fluid chamber of the housing by the shoes and the vanes to define phase-advance hydraulic chambers and phase-retard hydraulic chambers; an axially-slidable locking member located in one of the rotor and the housing; and a lock hole located in the other of the rotor and the housing, for restricting rotary motion of the vane rotor relative to the housing with the axially-slidable locking member engaged with the lock hole, wherein the rotor has a large-diameter portion formed between a first group of adjacent vanes of the plurality of vanes of the rotor and a small-diameter portion formed between a second group of adjacent radially-extending vanes of the plurality of vanes of the rotor, wherein an innermost end of a shoe of the plurality of shoes, opposed to an outer peripheral surface of the small-diameter portion, is configured to protrude radially inward rather than an innermost end of a shoe of the plurality of shoes, opposed to an outer peripheral surface of the large-diameter portion, and wherein the one of the axially-slidable locking member and the lock hole, located in the rotor, is arranged in an area except the small-diameter portion of the rotor.