Patent ID: 7143729

Claim:
A valve timing regulating apparatus arranged in a drive force transmission system for transmitting the drive force from a driving shaft of an internal combustion engine to a driven shaft for operating, opening and closing, at least one of an intake valve and an exhaust valve thereby to regulate operation timing of the opening and closing of at least one of the intake valve and the exhaust valve, comprising: a driving rotary member rotated by the drive force of the driving shaft; a driven rotary member relatively rotated to a retard side and a advance side with respect to the driving rotary member by pressure of working fluid of a retard chamber and an advance chamber thereby to transmit the drive force of the driving shaft to the driven shaft; a supply switching valve arranged in a supply path for supplying working fluid from a fluid source to the retard chamber and the advance chamber and capable of selectively switching communication only either between the retard chamber and the fluid source or between the advance chamber and the fluid source; a check valve arranged in the supply path for allowing working fluid to flow from the fluid source to the retard chamber and the advance chamber and prohibiting a flow of working fluid from the retard chamber and the advance chamber to the fluid source; and a discharge switching valve configured as a member independent of the supply switching valve and arranged in a discharge path for discharging working fluid from the retard chamber and the advance chamber, the discharge switching valve being capable of selectively switching communication only either between the retard chamber and a fluid discharge side or between the advance chamber and a fluid discharge side, and wherein the discharge switching valve communicates the fluid discharge side with the chamber other than the chamber with which the fluid source is communicated by the supply switching valve.