VALVE TIMING CONTROL DEVICE FOR INTERNAL COMBUSTION ENGINE

摘要

PROBLEM TO BE SOLVED: To improve the responsiveness to valve timing control and also surely reduce the sliding resistance of a plunger even for a vane body and a cylindrical member made of material of light specific gravity such as aluminum alloy. SOLUTION: A guide bushing 26 is fixed to a vane body 2, and a plunger 6 is slidably attached to the guide bushing 26. The tip of the plunger 6 is pressed against the inner face of a housing 1 by introducing the same pressure as that in a spark-advance side hydraulic chamber 12 into the pressure chamber 27 inside the plunger 6 in controlling the spark-advance side. The returning of the vane body 2 caused by the torque reaction from an engine valve is controlled by the stretching force of the plunger 6. A connection passage 30 communicating the pressure chamber 27 to a low pressure passage 29 is opened and closed in controlling the lag angle side. The vane body 2 is made of material of light specific gravity such as aluminum alloy, and the guide bushing 26 and the plunger 6 are made of iron system material similar to each other.