Fluid-operated servomotor for actuation of clutches or the like

摘要

A servomotor which actuates the throw-out device of a clutch, particularly in an automotive vehicle, has a piston which is reciprocable in a housing and is adapted to be coupled to a reciprocable motion transmitting rod for the throw-out device by a compensating device having cylindrical rollers which establish a motion transmitting connection between the piston and the rod as soon as the piston leaves its starting position in response to evacuation of air from the housing at one side of the piston. The rollers are automatically disengaged from the rod when the piston returns to its starting position so that the rod can be moved by the clutch in a first direction to compensate for wear upon the parts of the clutch or in a second direction to compensate for expansion of one or more friction discs in the clutch.