Rocker arm valve drive for lifting valve

摘要

The valve drive has a rocker arm between a cam and the valve, which can be turned by a bearing in the form of the piston of a hydraulic valve play reduction device. The piston (7) projects into a cavity (11) which is closed by a nonreturn valve (17) under pressure from the outside. The cavity can be opened by a control piston (22) which is acted on by hydraulic pressure on one side and a spring on the other. A spring (12) acting on the piston may be fitted in the cavity. A hydraulic channel (15) may run from the cavity so that the nonreturn valve has a flow round it which is perpendicular to the direction of motion of the nonreturn valve body.