Magnetic position sensor device, method and system, with error detection

Patent metadata

Field	Value
Publication number	US-11852507-B2
Application number	US-202218090123-A
Country	US
Kind code	B2
Filing date	Dec 28, 2022
Priority date	Dec 31, 2021
Publication date	Dec 26, 2023
Grant date	Dec 26, 2023

Abstract

A position sensor device includes: a first, second and third magnetic sensor for measuring a first magnetic field component oriented in the first direction, and a second magnetic field component oriented in a second direction perpendicular to the first direction; a processing circuit for determining a first and a second difference of signals provided by the first and third sensor, and for determining and outputting a first angle based on these differences; and for determining a third and a fourth difference of signals provided by the second sensor and one of the first and the third sensor; and for determining a second angle based on the third and the fourth difference, and for outputting the second angle and/or a diagnostic signal based on a comparison of the first and second angle.

First claim

The invention claimed is:

1. A position sensor device comprising:
a substrate comprising a first, a second and a third magnetic sensor spaced apart in a first direction, each magnetic sensor capable of measuring at least a first magnetic field component oriented in the first direction, and a second magnetic field component oriented in a second direction perpendicular to the first direction;
a processing circuit connected to said magnetic sensors, and configured for:
a) determining a first difference between the first magnetic field components provided by the first and the third sensor, and configured for determining a second difference between the second magnetic field components provided by the first and the third sensor, and for calculating a first angle based on a ratio of the first difference and the second difference, and for outputting the first angle as a first signal;
b) and for determining a third difference between the first magnetic field component provided by the second sensor and the first magnetic field component provided by one of the first and the third sensor;
c) and for determining a fourth difference between the second magnetic field component provided by the second sensor and the second magnetic field component provided by said one of the first and the third sensor;
d) and for determining a second angle based on the third and the fourth difference, and for outputting a second signal based on said second angle.

2. The position sensor device according to claim 1 , wherein the first, second and third sensor are located on a straight line; or
wherein the first, second and third sensor are located at the corners of a triangle.

3. The position sensor device according to claim 1 , wherein the second angle is calculated in accordance with the following formula: θaux12=atan2(ΔBx12, ΔBz12), where θaux12 is the second angle, ΔBx12 is the third difference, and ΔBz12 is the fourth difference.

4. The position sensor device according to claim 1 , wherein the processing circuit is further configured for calculating a fifth difference between the first magnetic field component provided by the second sensor and the first magnetic field component provided by the other one of the first and the third sensor; and
wherein the processing circuit is further configured for calculating a sixth difference between the second magnetic field component provided by the second sensor and the second magnetic field component provided by said other one of the first and the third sensor; and
wherein the processing circuit is further configured for calculating said second angle as a function of the third and the fourth and the fifth and the sixth difference.

5. The position sensor device according to claim 1 , wherein the first, second and third sensor are located on a straight line, and
wherein the second sensor is situated in the middle between the first and the third sensor.

6. The position sensor device according claim 1 , wherein each of the first, second and third sensor comprises an integrated magnetic concentrator and two horizontal Hall element arranged on opposite sides of the integrated magnetic concentrator.

7. The position sensor device according to claim 1 , wherein each of the first, second and third sensor comprises a horizontal Hall element and a vertical Hall element; or
wherein each of the first, second and third sensor comprises a horizontal Hall element and a pair of vertical Hall element located on opposite sides of the horizontal Hall element.

8. The position sensor device according to claim 1 , wherein each of the first, second and third sensor comprises two vertical Hall elements, having direction of maximum sensitivity which are perpendicular to each other; or
wherein each of the first, second and third sensor comprises two pairs of vertical Hall elements, arranged around a virtual square.

9. The position sensor device according to claim 1 , wherein each of the first and the third sensor comprise an integrated magnetic concentrator and four horizontal Hall element angularly spaced by multiples of 90°, consisting of a first and a second Hall element being spaced apart along the first direction, and a third and a fourth Hall element spaced apart in a direction perpendicular to the first direction;
wherein the first angle is calculated based on signals obtained from the first and the second Hall element; and
wherein the sensor device is further configured to determine a first sum as a sum of the signals obtained from the first and the second Hall element, and to calculate a second sum as a sum of the signals obtained from the third and the fourth Hall element, and to take into account a match of the first sum and the second sum when determining the second signal.

10. A magnetic position sensor system comprising:
a magnetic source for generating a magnetic field having at least two poles;
a position sensor device according to claim 1 , movable relative to said magnetic source, or vice versa.

11. The magnetic position sensor system according to claim 10 , wherein the magnetic source is a permanent magnet, rotatable about a rotation axis; and
wherein the position sensor device is mounted at a nonzero radial distance from the rotation axis, and is oriented such that the first direction is tangential to an imaginary circle having a centre on the rotation axis.

12. An angular position sensor system according to claim 11 , wherein the sensor device is arranged in one of the following ways:
i) wherein the substrate of the sensor device is oriented perpendicular to the rotation axis, and the magnet has an outer radius, and a geometric center of the sensors of the sensor device are located at a radial position of 30% to 95% of the outer radius, and at an axial position above a top surface or below a bottom surface of the magnet;
ii) wherein the substrate of the sensor device is oriented parallel to the rotation axis, and the magnet has an outer radius, and a geometric center of the sensors of the sensor device are located at a radial position of 30% to 95% of the outer radius, and at an axial position above a top surface or below a bottom surface of the magnet;
iii) wherein the substrate of the sensor device is oriented perpendicular to the rotation axis, and the magnet has an outer radius, and a geometric center of the sensors of the sensor device are located at a radial position of 105% to 200% of the outer radius, and at an axial position substantially inside the bottom surface or inside the top surface, or at an axial position between the bottom surface and the top surface;
iv) wherein the substrate of the sensor device is oriented parallel to the rotation axis, and the magnet has an outer radius, and a geometric center of the sensors of the sensor device are located at a radial position of 105% to 200% of the outer radius, and at an axial position substantially inside the bottom surface or inside the top surface, or at an axial position between the bottom surface and the top surface;
v) wherein the substrate of the sensor device is oriented perpendicular to the rotation axis, and the magnet has an outer radius, and a geometric center of the sensors of the sensor device are located at a radial position of 105% to 200% of the outer radius, and at an axial position above a top surface or below a bottom surface of the magnet;
vi) wherein the substrate of the sensor device is oriented parallel to the rotation axis, and the magnet has an outer radius, and a geometric center of the sensors of the sensor device are located at a radial position of 105% to 200% of the outer radius, and at an axial position above a top surface or below a bottom surface of the magnet

Assignees

• Melexis Tech Sa

Inventors

• Tombez Lionel
• Bidaux Yves
• Close Gael

Classifications

• G01D5/145 Primary

  influenced by the relative movement between the Hall device and magnetic fields (see G01R33/06) · CPC title

• G01B7/30

  for measuring angles or tapers; for testing the alignment of axes · CPC title

• G01B7/00 Primary

  Measuring arrangements characterised by the use of electric or magnetic techniques · CPC title

• G01D5/24461 Primary

  by redundancy or plausibility · CPC title

• G01D5/2451

  Incremental encoders (G01D5/2454 takes precedence) · CPC title