VALVE OPERATING DEVICE FOR USE IN INTERNAL COMBUSTION ENGINE

摘要

A valve operating device for operating an intake or exhaust valve in an internal combustion engine includes a cam having a cam profile including a valve lifting portion for applying a force to open the engine valve and a base circle portion for allowing the valve to be closed, the cam profile having a valve opening point and a valve closing point between the valve lifting portion and the base circle portion, a cam follower slidably engaging the cam, and a hydraulic lash adjuster combined with the cam follower for eliminating any gap between the means and the engine valve. The base circle portion has a gradient cam surface or a combination of different gradient cam surfaces for cancelling out valve-lifting radial displacement of the base circle portion.