Servo actuated valve for pressure medium, contains non rotating piston with communicating through channel and spiral groove

摘要

The piston (5) is prevented from rotating in relation to the valve housing and a channel (21-23) extends through the piston between the valve inlet (2) and outlet. This channel communicates with at least one spiral groove (18) linking the chambers (19) on either side of the piston, so that as the piston moves it is connected alternately to the inlet and outlet side chambers.