Variable timing valve gear for internal combustion engine, has cam follower bearing on rocker with movable fulcrum on arm containing piston

摘要

The cam (14) bears on a valve follower (13) which in turn pushes a rocker (18) with a central fulcrum (24). As the cam pushes the end of the rocker up, the other end pushes the valve stem (16) down. The rocker fulcrum is mounted on the end of a piston (19) inside a movable arm (M) on a shaft (10). Oil may flow down a channel (20) to push the fulcrum away from the shaft, to enable the valve to be actuated. Sideways movement of the fulcrum changes the valve lift.