Ascertaining a rotational angle of a steering shaft by means of three toothed gears

Abstract

The invention relates to a method for ascertaining a rotational angle (E) of a shaft (2). In order to increase the accuracy of the ascertainment within a greater predefined angle range in relation to the prior art, the following steps are provided: detecting respective rotational angles (W1, W2, W3) of three toothed gears (Z1, Z2, Z3) of a toothed gear arrangement, wherein the three toothed gears (Z1, Z2, Z3), with different numbers of teeth (z1, z2, z3), are meshed directly with a gear ring (10) of the shaft (2), and ascertaining the rotational angle (E) of the shaft (2) on the basis of the respective rotational angles (W1, W2, W3) of the three toothed gears (Z1, Z2, Z3) in accordance with a predetermined extraction rule, wherein the rotational angle (E) of the shaft (2) is distinctly defined within a predefined angle range by the entirety of the respective rotational angles (W1, W2, W3).

Dependencies are inferred from the claim text.