Electromechanical-hydraulic piston actuator and brake system

An electromechanical-hydraulic piston actuator for providing pressurized pressure medium for a brake system of a vehicle, comprising:

• an electric motor having a stator and a rotor,
• a rotation-translation mechanism which is driven in rotation by the electric motor and which has a rotatable threaded nut and a threaded spindle which is prevented from rotating and is mounted so as to be displaceable in its axial direction,
• a piston coupled with the threaded spindle in the axial direction thereof,
• a hydraulic cylinder having a hydraulic chamber which is filled with pressure medium and into which the piston is displaceable by translational movement of the threaded spindle from a rear piston position in the direction towards a forward piston position in order to pressurize the pressure medium and/or expel it from the chamber, a hydraulic connection which is connected to the chamber and via which pressure medium can be expelled from the chamber
• and
• a supporting structure to which the electric motor, the rotation-translation mechanism and the hydraulic cylinder are fastened,
• wherein there is provided an isolation device for the piston-travel-controlled isolation of the rotational coupling between the rotor of the electric motor and the threaded nut.