The invention relates to an electrical machine (8), in particular an electric motor, suitable for the adjustment by external force of elements of a motor vehicle, essentially for driving a steering booster. The inventive electrical machine comprises a rotor (7) and a shaft (10), the rotor having a plurality of plates (5), wherein the plates (5) are premounted on the shaft either individually or as a plate assembly (6) or by means of a plurality of plate assemblies (6), the rotor (7) being connected to the shaft (10). The plates (5) have resilient lugs (3) for fixing the plates (5) and/or plate assemblies (6) to the shaft (10). Furthermore, the plates (5) of the plate assemblies (6) comprise centering lugs (1) which serve to radially center the plate assembly (6) relative to the shaft (10). An attachment of the stator (15) in a housing part (16) is possible, wherein centering lugs (1) at the plates (5) of the plate assembly (6) of the stator (15) serve to center the plate assembly (6) of the stator (15) relative to the shaft (10).