Patent ID: 9133734
Filing Date: 2015-09-15
Classification: F01L

Abstract:
1. A valve timing control apparatus for an internal combustion engine, comprising: a housing to which a rotational force is transmitted from a crankshaft of the engine, the housing having shoes on an inner periphery thereof, a vane rotor fixed to a camshaft, the vane rotor cooperating with the shoes to define phase-advance hydraulic chambers and phase-retard hydraulic chambers therebetween, the vane rotor being rotatable relative to the housing toward a phase-advance side and a phase-retard side by a working fluid pressure that is selectively supplied to the phase-advance hydraulic chambers and the phase-retard hydraulic chambers and discharged therefrom, a first lock member and a second lock member respectively disposed on the vane rotor, the first lock member and the second lock member configured to be urged to project toward a side of the housing by a biasing member and allowed to retreat against a biasing force of the biasing member by a hydraulic pressure acting on a tip end portion of each of the first lock member and the second lock member, the hydraulic pressure being supplied separately from the working fluid pressure, a first lock concave portion disposed on the housing so as to be engaged with the tip end portion of the first lock member so as to restrain the vane rotor from being rotated from an intermediate phase position between a maximum phase-advance position and a maximum phase-retard position at least in a phase-advance direction; a second lock concave portion disposed on the housing so as to be engaged with the tip end portion of the second lock member so as to restrain the vane rotor from being rotated from the intermediate phase position between the maximum phase-advance position and the maximum phase-retard position at least in a phase-retard direction; and a communication passage formed as a groove that is formed on an axial end surface of the vane rotor so as to extend along a circumferential direction of the vane rotor, the groove being open to the axial end surface of the vane rotor and always opposed to the first lock concave portion and the second lock concave portion so as to always establish fluid communication between the first lock concave portion and the second lock concave portion and introduce the hydraulic pressure to allow the first lock member and the second lock member to retreat from the first lock concave portion and the second lock concave portion against the biasing force of the biasing member, wherein even when the vane rotor is rotationally moved between the maximum phase-advance position and the maximum phase-retard position, the first lock concave portion and the second lock concave portion always communicate with each other via the groove.