Patent attributes
A rotational angle sensor includes a stator element and rotor element. The stator element has a stator transmitting coil and stator receiving coil. The rotor element is rotatably mounted about a rotation axis, relative to the stator element, and has a rotor receiving coil and rotor transmitting coil electrically connected to each other. The rotor receiving coil is inductively coupled to the stator transmitting coil such that an electromagnetic field produced by the stator transmitting coil induces a current in the rotor receiving coil that flows through the rotor transmitting coil and causes the rotor transmitting coil to produce a further electromagnetic field. The stator receiving coil is inductively coupled to the rotor transmitting coil such that the inductive coupling between the stator receiving coil and the rotor transmitting coil is configured with reference to a rotational angle between the stator element and the rotor element, and such that the further electromagnetic field induces an angle-dependent alternating voltage in the stator receiving coil. The stator transmitting coil has a first circular outer partial winding, and a first circular inner partial winding positioned within and electrically connected to the first outer partial winding such that the first inner partial winding has an opposite current flow with respect to the first outer partial winding. The rotor receiving coil has a second circular outer partial winding and a second circular inner partial winding positioned within and electrically connected to the second outer winding such that the second inner winding has an opposite current flow with respect to the second outer partial winding. The first and second outer partial windings, and the first and second inner partial windings are oriented with respect to each other, respectively.