Patent ID: 7608962

Claim:
An electrical machine, comprising: a stator which bears a winding; a rotatable rotor, situated at a distance from the stator via an air gap, the rotor including at least two coaxial rotor sections which are rotatable relative to one another, in which each rotor section bears a system of permanent magnets having polarities which point outward radially in alternation; and an actuating device for rotating the rotor sections relative to one another; wherein the actuating device has a controllable actuator configured to align the rotor sections with one another with a variable rotary offset which is independent of a rotational speed of the rotor; and wherein the rotor sections are provided on shaft sections of a main shaft designed as a hollow shaft, in which an inner shaft is supported in an axially displaceable manner, and the actuator is designed as a displacement element for axial displacement of the inner shaft which, in mechanical linkage with a mutually engaged guide situated on the shafts, provides a freely selectable rotation and alignment of the rotor sections with respect to one another.