Patent ID: 9631524
Date: 2017-04-25
CPC Classifications: F01L

Claim:
1. A valve timing control apparatus of 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 each of the plurality of the working chambers into a phase-retard chamber and a phase-advance chamber in cooperation with the plurality of shoes; a lock mechanism interposed between the vane rotor and the housing for restricting rotary motion of the vane rotor relative to the housing depending on an engine operating condition; and a fluid-communication control mechanism (FCCM) formed in at least one of the plurality of vanes so as to form at least one FCCM-equipped vane, wherein the FCCM comprises a communication hole which permits fluid-communication between the phase-retard chamber and the phase-advance chamber defined by the at least one FCCM-equipped vane, and the FCCM is further configured to enable switching between a communication state and a non-communication state of the communication hole, wherein at least one of the plurality of vanes is configured without a FCCM so as to form at least one non-FCCM equipped vane, wherein the at least one non-FCCM equipped vane is configured such that a summed pressure-receiving surface area on a first side, facing the phase-retard chamber, and a summed pressure-receiving surface area on a second side, facing the phase-advance chamber, are set to differ from each other.