Valve timing control device

摘要

A valve timing control device for controlling the opening/closing timing of the intake valve or exhaust valve of an internal combustion engine is disclosed, comprising a valve opening/closing rotary shaft rotatably assembled with the cylinder head of the internal combustion engine; a rotation transmitting member mounted around the rotary shaft so as to rotate relative thereto within a predetermined range for transmitting a rotating power from a crank pulley; vanes provided on the rotary shaft are the rotation transmitting member; a fluid chamber formed between the rotary shaft and the rotation transmitting member and halved into advancing chambers and delaying chambers by the vanes; first fluid passages for feeding and discharging a fluid to and from the advancing chambers; second fluid passages for feeding and discharging the fluid to and from the delaying chambers; a refuge hole formed in the rotation transmitting member or the rotary shaft and accommodating therein a lock pin spring-biased toward the rotary shaft or the rotation transmitting member; a fitting hole formed in the rotary shaft or the rotation transmitting member for fitting therein the head portion of the lock pin when the rotary shaft and the rotation transmitting member are synchronized in predetermined relative phases; and a third passage for feeding and discharging the fluid to and from the fitting hole, wherein the fluid is a working oil and a back pressure chamber formed in the refuge hole at the back of the lock pin is given communication with the inside of the cylinder head of the internal combustion engine via a communication passage formed in the rotation transmitting member or the rotary shaft.