Sensor for the detection of the direction of a magnetic field

• US 20020021124A1
• Filed: 08/08/2001
• Published: 02/21/2002
• Est. Priority Date: 08/21/2000
• Status: Active Grant

• Current Assignee: Melexis Tessenderlo NV
• Original Assignee: Sentron AG (Sensinnovat BVBA)
• Inventors: Popovic, Radivoje, Schott, Christian, Racz, Robert
• Granted Patent: US 6,545,462 B2
• Time in Patent Office: Days
• US Class Current: 324/207.2
• CPC Class Codes: G01D 2205/40 Position sensors comprising arrangements for concentrating or redirecting magnetic flux
• CPC Class Codes: G01D 5/145 influenced by the relative movement between the Hall device and magnetic fields see G01R33/06
• CPC Class Codes: G01R 33/07 Hall effect devices
• CPC Class Codes: G01R 33/077 Vertical Hall-effect devices

Abstract

A sensor for the detection of the direction of a magnetic field comprises one single magnetic field concentrator with a flat shape and at least a first horizontal Hall-effect element and a second horizontal Hall-effect element, whereby the Hall-effect elements are arranged in the area of the edge of the magnetic field concentrator. Within its environment, the magnetic field concentrator alters the course of the field lines of the magnetic field and, in particular, has the effect that the field lines which, in the absence of the magnetic field concentrator would run parallel to the surface of the Hall-effect elements penetrate the Hall-effect elements almost vertically to their surface. Instead of horizontal Hall-effect elements, vertical Hall-effect elements can also be used when they are arranged beside the magnetic field concentrator.

The sensor is particularly suitable as an angle sensor.

Claims

1. Sensor for the detection of the direction of a magnetic field, comprising:

one single magnetic field concentrator with a flat shape,

at least a first Hall-effect element and a second Hall-effect element or at least a first group and a second group of Hall-effect elements, whereby the Hall-effect elements are arranged in the area of the edge of the magnetic field concentrator.

2. Sensor according to claim 1, wherein the magnetic field concentrator has a centre of symmetry, that a third Hall-effect element and a fourth Hall-effect element or a third group or a fourth group of Hall-effect elements is present whereby the Hall-effect elements are arranged in the area of the edge of the magnetic field concentrator, that the first Hall-effect element and the third Hall-effect element or the first group of Hall-effect elements and the third group of Hall-effect elements are arranged symmetrically in relation to the centre of symmetry, and that the second Hall-effect element and the fourth Hall-effect element or the second group of Hall-effect elements and the fourth group of Hall-effect elements are arranged symmetrically in relation to the centre of symmetry.

3. Sensor according to claim 1, wherein the Hall-effect elements are horizontal Hall-effect elements.

4. Sensor according to claim 2, wherein the Hall-effect elements are horizontal Hall-effect elements.

5. Sensor according to claim 3, wherein the Hall-effect elements are arranged on the side of the edge of the magnetic field concentrator facing the centre of the magnetic field concentrator.

6. Sensor according to claim 4, wherein the Hall-effect elements are arranged on the side of the edge of the magnetic field concentrator facing the centre of the magnetic field concentrator.

7. Sensor according to claim 1, wherein the Hall-effect elements are vertical Hall-effect elements and wherein the Hall-effect elements are arranged outside the magnetic field concentrator.

8. Sensor according to claim 2, wherein the Hall-effect elements are vertical Hall-effect elements and wherein the Hall-effect elements are arranged outside the magnetic field concentrator.

12. Sensor according to claim 1, wherein the magnetic field concentrator is made of metal glass.

13. Sensor according to claim 2, wherein the magnetic field concentrator is made of metal glass.

15. Use of a sensor according to claim 1 as an angle sensor for determining the rotational position of an object rotatable around a rotary axis, whereby a permanent magnet is secured to the rotary axis, wherein the distance between the sensor and the permanent magnet is selected so that the magnetic field concentrator is magnetically at least partially saturated.

16. Use of a sensor according to claim 2 as an angle sensor for determining the rotational position of an object rotatable around a rotary axis, whereby a permanent magnet is secured to the rotary axis, wherein the distance between the sensor and the permanent magnet is selected so that the magnetic field concentrator is magnetically at least partially saturated.

17. Use of a sensor according to claim 3 as an angle sensor for determining the rotational position of an object rotatable around a rotary axis, whereby a permanent magnet is secured to the rotary axis, wherein the distance between the sensor and the permanent magnet is selected so that the magnetic field concentrator is magnetically at least partially saturated.

18. Use of a sensor according to claim 4 as an angle sensor for determining the rotational position of an object rotatable around a rotary axis, whereby a permanent magnet is secured to the rotary axis, wherein the distance between the sensor and the permanent magnet is selected so that the magnetic field concentrator is magnetically at least partially saturated.

19. Use of a sensor according to claim 5 as an angle sensor for determining the rotational position of an object rotatable around a rotary axis, whereby a permanent magnet is secured to the rotary axis, wherein the distance between the sensor and the permanent magnet is selected so that the magnetic field concentrator is magnetically at least partially saturated.

20. Use of a sensor according to claim 6 as an angle sensor for determining the rotational position of an object rotatable around a rotary axis, whereby a permanent magnet is secured to the rotary axis, wherein the distance between the sensor and the permanent magnet is selected so that the magnetic field concentrator is magnetically at least partially saturated.

21. Use of a sensor according to claim 7 as an angle sensor for determining the rotational position of an object rotatable around a rotary axis, whereby a permanent magnet is secured to the rotary axis, wherein the distance between the sensor and the permanent magnet is selected so that the magnetic field concentrator is magnetically at least partially saturated.

22. Use of a sensor according to claim 8 as an angle sensor for determining the rotational position of an object rotatable around a rotary axis, whereby a permanent magnet is secured to the rotary axis, wherein the distance between the sensor and the permanent magnet is selected so that the magnetic field concentrator is magnetically at least partially saturated.

9. Sensor for the detection of the direction of a magnetic field, comprising:

at least three magnetic field concentrators arranged symmetrically in one plane in relation to a point of symmetry with which facing, neighbouring margins run partially parallel to each other in the area of the point of symmetry, and

one Hall-effect element or one group of Hall-effect elements per magnetic field concentrator, whereby the Hall-effect elements are arranged in the area of the parallel running margin of the edge of the respective magnetic field concentrator.

10. Sensor according to claim 9, wherein the Hall-effect elements are horizontal Hall-effect elements.

11. Sensor according to claim 9, wherein the Hall-effect elements are vertical Hall-effect elements.

14. Sensor according to claim 9, wherein the magnetic field concentrators are made of metal glass.