Compact device for measuring magnetic fields having magnetoresistors and an auxiliary magnetic field generator
First Claim
1. A device for measuring magnetic fields, comprising:
- an assembly of at least two magnetic field sensors, each of which comprises a number of magnetoresistive sensor elements situated in one plane and which have the same privileged directions of magnetization, said sensor elements including means for connection to a power supply circuit and to a signal processing circuit, the privileged directions of magnetization of the sensor elements of the at least two magnetic field sensors being different, said assembly of magnetic field sensors being arranged within a magnetization coil comprising an electric conductor having a number of turns and which extends around a central axis and which is arranged to generate an auxiliary magnetic field extending parallel to the central axis, the magnetic field sensors being arranged within the magnetization coil in a manner such that the angle enclosed by the central axis relative to a normal to the plane of the sensor elements is the same for each of the magnetic field sensors and so that the auxiliary magnetic field at the area of each of the magnetic field sensors contains a component which extends parallel to the privileged direction of magnetization of the sensor elements of the relevant magnetic field sensor, wherein the direction of the auxiliary magnetic field encloses the same angle α
relative to the privileged direction of magnetization of the sensor elements of each of the magnetic field sensors, where 0°
<
α
<
90°
.
4 Assignments
0 Petitions
Accused Products
Abstract
A device for measuring magnetic fields comprises an assembly of at least two magnetic field sensors each of which comprises a number of magnetoresistive sensor elements situated in one plane and which have the same privileged directions of magnetization, said sensor elements being connected to a power supply circuit and to a signal processing circuit. The privileged directions of magnetization of the sensor elements of different magnetic field sensors are different. The assembly of magnetic field sensors is arranged within a magnetization coil made of a number of turns of an electric conductor extending around a central axis so as to generate an auxiliary magnetic field extending parallel to the central axis. The magnetic field sensors are arranged within the magnetization coil so that the angle enclosed by the central axis relative to the normal to the plane of the sensor elements is the same for each of the magnetic field sensors and the auxiliary magnetic field at the area of each of the magnetic field sensors contains a component which is parallel to the privileged direction of magnetization of the sensor elements of the relevant magnetic field sensor. The sensor part formed by the magnetic field sensors and the magnetization coil is small and light because the direction of the auxiliary magnetic field encloses the same angle α relative to the privileged direction of magnetization of the sensor elements of each of the magnetic field sensors, where 0°<α<90°.
33 Citations
14 Claims
-
1. A device for measuring magnetic fields, comprising:
- an assembly of at least two magnetic field sensors, each of which comprises a number of magnetoresistive sensor elements situated in one plane and which have the same privileged directions of magnetization, said sensor elements including means for connection to a power supply circuit and to a signal processing circuit, the privileged directions of magnetization of the sensor elements of the at least two magnetic field sensors being different, said assembly of magnetic field sensors being arranged within a magnetization coil comprising an electric conductor having a number of turns and which extends around a central axis and which is arranged to generate an auxiliary magnetic field extending parallel to the central axis, the magnetic field sensors being arranged within the magnetization coil in a manner such that the angle enclosed by the central axis relative to a normal to the plane of the sensor elements is the same for each of the magnetic field sensors and so that the auxiliary magnetic field at the area of each of the magnetic field sensors contains a component which extends parallel to the privileged direction of magnetization of the sensor elements of the relevant magnetic field sensor, wherein the direction of the auxiliary magnetic field encloses the same angle α
relative to the privileged direction of magnetization of the sensor elements of each of the magnetic field sensors, where 0°
<
α
<
90°
. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9)
- an assembly of at least two magnetic field sensors, each of which comprises a number of magnetoresistive sensor elements situated in one plane and which have the same privileged directions of magnetization, said sensor elements including means for connection to a power supply circuit and to a signal processing circuit, the privileged directions of magnetization of the sensor elements of the at least two magnetic field sensors being different, said assembly of magnetic field sensors being arranged within a magnetization coil comprising an electric conductor having a number of turns and which extends around a central axis and which is arranged to generate an auxiliary magnetic field extending parallel to the central axis, the magnetic field sensors being arranged within the magnetization coil in a manner such that the angle enclosed by the central axis relative to a normal to the plane of the sensor elements is the same for each of the magnetic field sensors and so that the auxiliary magnetic field at the area of each of the magnetic field sensors contains a component which extends parallel to the privileged direction of magnetization of the sensor elements of the relevant magnetic field sensor, wherein the direction of the auxiliary magnetic field encloses the same angle α
-
10. A magnetoresistive device comprising:
-
first and second magnetic field sensors each of which comprises a plurality of magnetoresistive sensor elements connected together to form respective Wheatstone bridge circuits and each situated in one plane, and wherein the magnetoresistive sensor elements of each magnetic field sensor have the same privileged direction of magnetization with the privileged direction of magnetization of the first magnetic field sensor being different from that of the second magnetic field sensor, a magnetization coil magnetically coupled to said first and second magnetic field sensors to produce an auxiliary magnetic field parallel to a central axis thereof and positioned such that an angle enclosed by the central axis relative to a normal to the plane of the sensor elements is the same for each of the magnetic field sensors and so that the auxiliary magnetic field at the area of each of the magnetic field sensors contains a component which extends parallel to the privileged direction of magnetization of the sensor elements of the relevant magnetic field sensor, wherein the direction of the auxiliary magnetic field encloses the same angle α
relative to the privileged direction of magnetization of the sensor elements of each of the magnetic field sensors, where 0°
<
α
<
90°
, andmeans for coupling the Wheatstone bridge circuits to a source of supply voltage and to a signal processing circuit. - View Dependent Claims (11, 12, 13, 14)
-
Specification