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Arrangement for measuring the angular position of an object, using planar magnetoresistive sensors (6, 9) through which an electric current flows and which are arranged in a magnetic field which is parallel to their respective planes, which magnetic field is generated by an arrangement of magnets (4

Arrangement for measuring the angular position of an object, using planar magnetoresistive sensors (6, 9) through which an electric current flows and which are arranged in a magnetic field which is parallel to their respective planes, which magnetic field is generated by an arrangement of magnets (4, 14) rotatably journaled eccentrically on a shaft (11), the angular position of the shaft (11) corresponding to that of the object to be measured.

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The invention claimed is: 1. A device for measuring the angular position of a shaft with respect to an axis of rotation of the shaft that extends longitudinally within said shaft, comprising: a plurality of magnets configured for rotation with said shaft about said axis of rotation, the plurality o

The invention claimed is: 1. A device for measuring the angular position of a shaft with respect to an axis of rotation of the shaft that extends longitudinally within said shaft, comprising: a plurality of magnets configured for rotation with said shaft about said axis of rotation, the plurality of magnets generating a magnetic field; and a plurality of planar magnetoresistive sensors through which, for each sensor, an electric current flows parallel to a respective plane passing through a respective one of the sensors and being disposed such that said respective plane is arranged in parallel with said magnetic field, wherein the plurality of magnets are configured and disposed to collectively have rotational symmetry about a point offset from said axis of rotation such that the plurality of magnets do not collectively have rotational symmetry about said axis of rotation. 2. A device as claimed in claim 1, wherein said respective plane parallel to a first of said sensors is perpendicular to said respective plane parallel to a second of said sensors. 3. A device as claimed in claim 1, wherein the plurality of magnets includes a permanent magnet and an external ferromagnetic circuit, and air gap existing in between the permanent magnet and the circuit. 4. A device as claimed in claim 3, wherein said air gap is filled with a non-conducting material. 5. A device as claimed in claim 1, wherein an annular magnetization in a permanent-magnetic material generates the field. 6. A device as claimed in claim 3, wherein one of the respective planes and another of the respective planes are both parallel to an axis of rotation of said object. 7. A device as claimed in claim 1, wherein said plurality of planar magnetoresistive sensors consists of two sensors, said two sensors being arranged on a common carrier plate perpendicularly to said plate. 8. A device as claimed in claim 7, wherein the carrier plate is arranged perpendicularly to an axis of rotation of an object whose angular position is to be measured by said device, said object being connected to said shaft. 9. A device as claimed in claim 1, wherein the magnetoresistive sensors form part of an integrated circuit. 10. A device as claimed in claim 1, the plurality of magnetoresistive sensors includes a Wheatstone bridge with four magnetoresistive resistors. 11. The device of claim 1, wherein said shaft is connected to an object whose angular position is to be measured by said device. 12. The device of claim 1, wherein the plurality of magnets are supported by a structure implemented for rotation with said shaft. 13. The device of claim 12, wherein said shaft has an end upon which said structure is mounted. 14. The device of claim 1, configured such that rotation of said shaft through an angle of rotation rotates said plurality of magnets through an identical angle of rotation. 15. The device of claim 1, wherein the plurality of magnets are configured and disposed to collectively have axial symmetry. 16. A device for measuring the angular position of a shaft, comprising: a plurality of magnets configured for rotation with said shaft, the plurality of magnets generating a magnetic field; and a plurality of planar magnetoresistive sensors through which, for each sensor, an electric current flows parallel to a respective plane passing through each of a respective one of said sensors and being disposed such that each respective plane is arranged in parallel with said magnetic field; wherein, the plurality of magnets include a permanent magnet, and a cross-section of the permanent magnet as viewed along an axis of rotation of said shaft that extends longitudinally within said shaft lacks rotational symmetry, and wherein the plurality of magnets are configured and disposed to collectively have rotational symmetry about a point offset from said axis of rotation. 17. The device of claim 16, wherein said shaft is connect to an object such that an angular position of the shaft corresponds to that of said object and wherein the permanent magnet has a cam-shaped cross-section. 18. The device of claim 16, wherein the plurality of magnets are supported by a structure implemented for rotation with said shaft and wherein said shaft has an end upon which said structure is mounted. 19. The device of claim 16, configured such that rotation of said shaft through an angle of rotation rotates said plurality of magnets through an identical angle of rotation. 20. The device of claim 16, wherein said collective cross-section as viewed along said axis lacks radial symmetry. 21. A device for measuring an angular position of a shaft having an axis of rotation that is longitudinally within the shaft, comprising: a magnetic arrangement generating a magnetic field extending in a direction from an inner magnetic portion to an outer magnetic portion, the inner magnetic portion and the outer magnetic portion separated by a substantially nonmagnetic portion that the generated magnetic field extends across, and coupled to said shaft for 360 degrees of rotation with said shaft about the axis of rotation, the magnetic arrangement including a plurality of magnets configured and disposed to collectively have rotational symmetry about a point offset from said axis of rotation; and a magnetoresistive sensor for determining the angular position of said shaft by sensing an angle of the magnetic field dependent upon a position of the magnetoresistive sensor in said direction and relative to the inner magnetic portion and the outer magnetic portion, wherein the magnetoresistive sensor's position from the inner portion and the outer portion is a function of the angular position of the shaft. 22. The device of claim 21, further including another magnetoresistive sensor, wherein the magnetoresistive sensors are positioned perpendicular to the axis of rotation and at a same distance from the axis of rotation and where the magnetoresistive sensors are situated at about a 90 degree angle from each other relative to the axis of rotation.