Inductive position sensor
An inductive position sensor including a stator element having an exciter coil to which a periodic alternating voltage is applied and having a receiving system, wherein the signal of the exciter coil is inductively coupled into the receiving system. A rotor element influences the strength of the inductive coupling between the exciter coil and the receiving system according to its angular position relative to the stator element. An evaluation circuit determines the angular position of the rotor element relative to the stator element from the voltage signals induced in the receiving system. The position sensor has an unambiguous range E, in which the angular position can be unambiguously determined. The receiving system extends over a first angular range, wherein the first angular range is N 1 =n*E where n≥1, and the exciter coil extends over a second angular range, wherein the second angular range is N 2 =m*E where m≥2.
1. An inductive position sensor comprising:
a stator element having an exciter coil to which a periodic alternating voltage is applied and having a receiving system, a signal of the exciter coil being inductively coupled into the receiving system;
a rotor element that influences a strength of the inductive coupling between the exciter coil and the receiving system according to an angular position of the rotor element relative to the stator element; and
an evaluation circuit to determine the angular position of the rotor element relative to the stator element from voltage signals induced in the receiving system,
wherein the inductive position sensor has an unambiguous range E, in which the angular position is unambiguously determined,
wherein the receiving system extends over a first angular range,
wherein the first angular range is N 1 =n*E where n≥1,
wherein the exciter coil extends over a second angular range,
wherein the second angular range is N 2 =m*E where m≥2,
wherein m and n are positive whole numbers and m>n, and
wherein the unambiguous range E is determined according to the formula:
E= 360°/Number of blades of the rotor element.
2. The inductive position sensor according to claim 1 , wherein m≥n+1, or wherein m=n+1.
3. The inductive position sensor according to claim 1 , wherein the geometry of the rotor element is described by two circular paths with different radii around a center point, wherein a first radius of a first of the two circular paths is smaller than a second radius of a second of the two circular paths, and a section of an outer contour extends alternately and uniformly on the first or the second circular path, and the ends of the sections are connected by a radial connection between the circular paths to the respective adjacent sections on the respective other circular path.
4. The inductive position sensor according to claim 3 , wherein the section on the circular path with the second radius forms a blade and the section on the circular path with the first radius forms a gap.
5. The inductive position sensor according to claim 1 , wherein the receiving system has at least two or three first conductor loops.
6. The inductive position sensor according to claim 5 , wherein the first conductor loops each form a uniformly repeating loop structure.
7. The inductive position sensor according to claim 6 , wherein a winding direction of the first conductor loops of the uniformly repeating loop structure changes, wherein an area is spanned by the change of the winding direction.
8. The inductive position sensor according to claim 5 , wherein the stator element and the evaluation circuit are arranged on a printed circuit board, wherein the evaluation circuit is arranged inside the exciter coil and outside the first conductor loops of the receiving system.
9. An inductive position sensor comprising:
a stator element having an exciter coil to which a periodic alternating voltage is applied and having a receiving system, a signal of the exciter coil being inductively coupled into the receiving system;
a coupling element that influences the strength of the inductive coupling between the exciter coil and the receiving system according to a linear position of the coupling element relative to the stator element; and
an evaluation circuit to determine the linear position of the coupling element relative to the stator element from voltage signals induced in the receiving system,
wherein the inductive position sensor has an unambiguous range E in which the linear position is unambiguously determined,
wherein the receiving system extends over a first length range,
wherein the first length range is L 1 =n*E where n≥1,
wherein the exciter coil extends over a second length range,
wherein the second length range is L 2 =m*E where m≥2,
wherein m and n are positive whole numbers and m>n, and
wherein the inductive position sensor is a linear sensor.
10. The inductive position sensor according to claim 1 , wherein the inductive position sensor is a segment sensor.