Timing gear for 4-stroke combustion engines has valve lifter connected to hydraulic control piston, and two cylinder pressure chambers connected to pressure source/reducer via rotary slide valves

摘要

A valve lifter (1) is fastened to the regulator piston (2) of a hydraulic control cylinder (3). The piston separates two pressure chambers (4,5) within the cylinder, each with an intake and an outlet (6,7). The intake is connected to a pressure source, and the outlet is connected to a pressure reducer via a control unit (8), so that the valve lifter can open and close the valve cyclically. The pressure chambers are connected to pressure source and reducer via two rotary slide valves (9), which re contained in the control unit.