Measuring system

Patent metadata

Field	Value
Publication number	US-10816611-B2
Application number	US-201715666050-A
Country	US
Kind code	B2
Filing date	Aug 1, 2017
Priority date	Aug 1, 2016
Publication date	Oct 27, 2020
Grant date	Oct 27, 2020

Abstract

A measuring system having a magnetic device for generating a magnetic field and at least one magnetic field sensor for detecting a flux density of the magnetic field, at least in a first spatial direction. The magnetic device has a top side facing the magnetic field sensor, the magnetic field sensor is spaced apart from the top side of the magnetic device, the magnetic device has a main magnet, having two poles, with a main magnetizing direction for generating a main magnetic field and at least one secondary magnet, having two poles, with a secondary magnetization direction for generating a secondary magnetic field, the main magnet has larger dimensions than the at least one secondary magnet, the magnetic field is formed by superposition of the main magnetic field and the secondary magnetic field, the secondary magnetic field at least partially compensates the main magnetic field in the first spatial direction.

First claim

What is claimed is:

1. A measuring system comprising:
a magnetic device for generating a magnetic field; and
at least one magnetic field sensor for detecting a flux density of the magnetic field at least in a first spatial direction,
wherein the magnetic device has a top side facing the at least one magnetic field sensor,
wherein the at least one magnetic field sensor is spaced at a first distance from the top side of the magnetic device,
wherein the magnetic device has a main magnet having two permanent magnetic poles with a main magnetization direction for generating a main magnetic field,
wherein the magnetic device has at least one secondary magnet having two permanent magnetic poles with a secondary magnetization direction for generating a secondary magnetic field,
wherein the main magnet has larger dimensions than the at least one secondary magnet,
wherein the magnetic field is formed by superimposing the main magnetic field and the secondary magnetic field,
wherein the secondary magnetic field at least partially compensates the main magnetic field in the first spatial direction,
wherein the top side of the magnetic device is formed as a planar surface with a first surface region and a second surface region,
wherein the first surface region is formed by at least one pole of the main magnet,
wherein the second surface region is formed by at least one pole of the at least one secondary magnet,
wherein the at least one magnetic field sensor at least partially covers the second surface region in a projection extending substantially perpendicular to the top side of the magnetic device, and
wherein the at least one secondary magnet contacts the main magnet on four sides of the at least one secondary magnet, the four sides being orthogonal to the top side, or wherein a bottom side of the at least one secondary magnet opposite the top side contacts a bottom surface of at least one recess, the bottom surface being spaced apart from the top side in a first direction orthogonal to the top side such that the at least secondary magnet is arranged between the bottom surface and the at least one magnetic field sensor.

2. The measuring system according to claim 1 , wherein the second surface region of the top side is completely enclosed by the first surface region or the second surface region is surrounded by the first surface region on two opposite sides.

3. The measuring system according to claim 1 , wherein the magnetic device is cuboid.

4. The measuring system according to claim 1 , wherein the at least one secondary magnet is cuboid, and wherein the at least one recess has a negative shape of the secondary magnet.

5. The measuring system according to claim 1 , wherein the magnetic device is cylindrical, and wherein a base surface forms the top side of the magnetic device.

6. The measuring system according to claim 1 , wherein the main magnetization direction of the main magnet is oriented in a substantially same or reverse direction as the secondary magnetization direction of the at least one secondary magnet.

7. The measuring system according to claim 1 , further comprising a first secondary magnet with a first secondary magnetization direction and a second secondary magnet with a second secondary magnetization direction.

8. The measuring system according to claim 7 , wherein the first secondary magnetization direction runs in a substantially same or reverse direction to the second secondary magnetization direction.

9. The measuring system according to claim 8 , wherein the measuring system comprises a first magnetic field sensor and a second magnetic field sensor, wherein the first magnetic field sensor and the second magnetic field sensor are arranged next to one another in a plane extending parallel to the top side of the magnetic device, and wherein the first magnetic field sensor at least partially covers the first secondary magnet and the second magnetic field sensor of the second secondary magnet in a projection substantially perpendicular to the top side.

10. The measuring system according to claim 1 , wherein the main magnetization direction of the main magnet runs orthogonal or substantially parallel to the top side of the magnetic device.

11. The measuring system according to claim 1 , wherein the secondary magnetization direction of the secondary magnet runs orthogonal or substantially parallel to the top side of the magnetic device.

12. The measuring system according to claim 1 , wherein the magnetic device and the at least one magnetic field sensor are integrated in a component package, the component package being designed for mounting on a circuit board.

13. The measuring system according to claim 1 , wherein the measuring system has an encoder which is movable at least in one direction relative to the magnetic device.

14. A measuring system comprising:
a magnetic device for generating a magnetic field; and
at least one magnetic field sensor for detecting a flux density of the magnetic field at least in a first spatial direction,
wherein the magnetic device has a top side facing the at least one magnetic field sensor,
wherein the at least one magnetic field sensor is spaced at a first distance from the top side of the magnetic device,
wherein the magnetic device has a main magnet having two permanent magnetic poles with a main magnetization direction for generating a main magnetic field,
wherein the magnetic device has a secondary magnet having two permanent magnetic poles with a secondary magnetization direction for generating a secondary magnetic field,
wherein the main magnet has larger dimensions than the secondary magnet,
wherein the magnetic field is formed by superimposing the main magnetic field and the secondary magnetic field,
wherein the secondary magnetic field at least partially compensates the main magnetic field in the first spatial direction,
wherein the top side of the magnetic device is formed as a planar surface with a first surface region and a second surface region,
wherein the first surface region is formed by at least one pole of the main magnet,
wherein the second surface region is formed by at least one pole of the secondary magnet,
wherein the at least one magnetic field sensor at least partially covers the second surface region in a projection extending substantially perpendicular to the top side of the magnetic device, and
wherein the main magnetization direction between the two permanent magnetic poles of the main magnet is oriented orthogonal to the secondary magnetization direction between the two permanent magnetic poles of the secondary magnet.

Assignees

• TDK—Micronas GmbH
• Tdk Micronas Gmbh

Inventors

• Kaufmann Timo
• Franke Joerg

Classifications

• G01R33/02 Primary

  Measuring direction or magnitude of magnetic fields or magnetic flux (G01R33/20 takes precedence) · CPC title

• G01D5/145

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

• G01B7/023

  for measuring distance between sensor and object (G01B7/082 and G01B7/102 take precedence) · CPC title

• G01R33/07 Primary

  Hall effect devices · CPC title

• G01R33/0047

  Housings or packaging of magnetic sensors (packaging of semiconductor devices H10W99/00); Holders · CPC title