Superimposition installation of speed for a steering system.

- Device for imposing rotational speeds for a steering system for vehicles, with: - an output shaft (4), which is aligned to the drive shaft (1) in its axial direction, - a support arrangement (8) , which houses, at least partially, the drive shaft (1) and the output shaft (4), positioned rotatably, - an auxiliary drive (6, 7) with a rotor (6) which is connected fixed against rotation with a wave generator (5), as an oval disc, on whose periphery a flexible ring (2) with external toothing is directly hosted or indirectly, wherein the external toothing engages in an internal toothed wheel (3), the least two peripheral points, in which the support arrangement (8) is arranged fixed to the bodywork, the output shaft (4) is fixed connected rotationally with the internal gear (3), the shaft (1 ) is connected fixed against rotation with the flexible ring (2) with ntado outside and in that the drive shaft (19 and the output shaft (4) are mounted freely rotatable independently of each other and that the device has a locking device (9, 310), in aso fault, blocks the rotor (6) with the stator (7) and / or the support arrangement (8) rotationally fixed manner, wherein the rotor (6) is connected rotationally with a first contact element (308) ferromagnetic or permanent magnet, concentrically surrounding the axial direction of the output shaft (4) and the shaft (1) so that the optionally fixed engagement against rotation between the output shaft (4) and the shaft (1 ) can be achieved by a frictional connection of the first contact element (308) with a second contact element (309) which is connected rotationally with the support arrangement (8), and the pressing force torque needed for fu erza ​​friction is generated by a magnetic force and wherein at least one of the two contact elements (308, 309) is axially displaceable.