VALVE TIMING CONTROL APPARATUS OF INTERNAL COMBUSTION ENGINE

摘要

In a valve timing control apparatus configured to enable rotary motion of a vane rotor relative to a sprocket in a phase-retard direction or in a phase-advance direction by controlling hydraulic-pressure supply-and-exhaust for each of phase-advance hydraulic chambers and hydraulic-pressure supply-and-exhaust for each of phase-retard hydraulic chambers, first and second lock pins are located in a large-diameter rotor portion rather than a small-diameter rotor portion. The rotary motion of the vane rotor relative to the sprocket from an intermediate lock position between a maximum phase-advance position and a maximum phase-retard position is restricted by engagement of the first lock pin with a first lock hole and by engagement of the second lock pin with a second lock hole. The vane rotor is held at the maximum phase-retard position by engagement of the first lock pin with the second lock hole.

主权项

1. A valve timing control apparatus of an internal combustion engine, comprising:
a housing adapted to be driven by a crankshaft of the engine, and configured to define a working-fluid chamber therein by partitioning an internal space by 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 radially-extending vanes formed on an outer periphery of the rotor for partitioning the working-fluid chamber of the housing by the shoes and the vanes to define phase-advance hydraulic chambers and phase-retard hydraulic chambers; a stopper for restricting an angular range of relative rotation of the vane rotor with respect to the housing; a first locking member located in the vane rotor and configured to extend or retract as necessary; a second locking member located in the vane rotor and configured to extend or retract as necessary; a third locking member located in the vane rotor and configured to extend or retract as necessary; a first lock recessed portion configured to restrict rotary motion of the driven rotary member relative to the driving rotary member in a phase-retard direction from an intermediate lock position between a maximum phase-advance position and a maximum phase-retard position by engagement of the first locking member with the first lock recessed portion; a second lock recessed portion configured to restrict rotary motion of the driven rotary member relative to the driving rotary member in a phase-advance direction from the intermediate lock position by engagement of the second locking member with the second lock recessed portion; and a third lock recessed portion located in the housing, and having a stepped portion whose bottom face lowers stepwise in the phase-advance direction, and configured to guide the first locking member toward the first lock recessed portion by virtue of movement of the third locking member into engagement with the third lock recessed groove, and further configured to hold the vane rotor at the maximum phase-retard position by restricting the rotary motion of the vane rotor in the phase-advance direction by engagement of the second locking member with the third lock recessed portion under a state where the rotary motion of the vane rotor relative to the housing in the phase-retard direction is restricted by the stopper.