Patent ID: 8118149

Claim:
A selective freewheeling mechanism for expanding an electromechanical vehicle brake into a parking brake, comprising: an outer ring; a locking element cage disposed in the outer ring; a shaft disposed in the locking element cage; and a plurality of locking elements disposed between the shaft and the outer ring; wherein the outer ring, the locking element cage, the shaft and the locking elements are arranged such that the freewheeling mechanism is disengaged when the locking element cage is pivoted relative to the outer ring about a rotation axis into a disengagement position which moves the locking elements into a disengagement position away from the shaft such that the outer ring and the shaft are rotatable relative to one another, wherein the freewheeling mechanism is engaged when the locking element cage is pivoted relative to the outer ring about said rotation axis into an engagement position which moves the locking elements into an engagement position with the shaft in which the locking elements lock the shaft and the outer ring against a rotation relative to one another in a locking direction, but which allow the outer ring and the shaft to rotate relative to one another in an opposite freewheeling direction, and wherein the locking element cage and the outer ring are embodied as a rotor and stator of an electric motor having at least one coil arranged such that, when current is applied to the coil, the locking element cage and the outer ring are pivoted relative to one another about said rotation axis into the engagement or disengagement position.