A pneumatic servo for operating a switching valve (18, 19), e.g. for a turbocharger in an IC engine, has a sealed housing divided by a flexible membrane into an upper chamber (4c) and a lower chamber (6c). A thrust rod (14c) is attached to the membrane and...

An EGR valve for a turbocharged diesel engine has valve having a valve closure member (12) movable relative to a mating surface (14) for regulating the flow of EGR gases and a first actuator (16) for enabling the position of the valve closure member (12) t...