Electro-hydraulic valve drive for stroke-variable actuation of gas exchange valve of internal combustion engine, has supply channel positioned such that channel opening is opened in extended position of actuator piston

摘要

The drive (1) has a control channel (12) connecting a pressure chamber (11) with a pressure relief chamber (13). An electrically controllable hydraulic valve (14) releases or blocks flow of a hydraulic medium through the channel. A supply channel (17) separately runs to the control channel, and opens into a region of a guide (3) in the pressure chamber. The supply channel is positioned such that a channel opening (19) is opened in an extended position of an actuator piston (5) and is closed by an outer casing surface in a retracted position of the piston.