Apparatus and method for controlling movement of at least one valve for a combustion chamber of an internal combustion engine

摘要

An apparatus for controlling movement of a valve(s) 27a for a combustion chamber of an internal combustion engine comprising a master piston 201 having a first end portion 202 with a first actuation surface 203 and a second different actuation surface 205, a first slave piston 23a configured to actuate the valve and to be hydraulically moved in dependence on movement of the master piston and a control system 207 configured to in a first mode, enable movement of the first slave piston via movement of the first actuation surface and the second actuation surface and in a second mode, enable movement of the first slave piston, via movement of the first actuation surface, but not via movement of the second actuation surface. A method of operation, a valve train, an internal combustion engine, a vehicle and a system are also claimed.