Displacement Detection Device Using Magnetic Concentrators

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional displacement detection devices require expensive magnetic multipole magnets, increasing costs and limiting the detectable range to the pitch of the magnetic detection element.

Innovation Solution

A displacement detection device using a rod-shaped magnet with a predetermined angle and pairs of magnetic detection element groups with magnetic concentrators to detect magnetic flux density, allowing for wider detection ranges with monopole magnets by reducing disturbance noise.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Length of stationary object

If a magnetic multipole magnet is used to expand the magnetic field range, then the detectable displacement range is widened, but the cost increases

Engineering Contradiction:
Improvedetectable displacement rangeVSAvoidcost
Core Design Contradiction:
Length of stationary objectVSEase of manufacture

Solution Approach 1:

Magnetic concentrators are introduced as intermediary elements between the monopole magnet and the magnetic detection elements. These concentrators reshape and redirect the magnetic flux from the monopole magnet to create an extended magnetic field range, achieving the same effect as a multipole magnet but with a simpler, cheaper monopole configuration

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The invention changes the magnetic field distribution parameters by using multiple magnetic concentrators positioned at specific intervals around the monopole magnet. This reconfigures the magnetic flux density distribution to extend the detectable range while maintaining cost-effectiveness with a monopole design

Inventive Principle:
Principle #35Parameter changes

2Ease of manufacture

If a monopole magnet is used to reduce cost, then the manufacturing cost decreases, but the detectable range is limited to the pitch of the magnetic detection element

Engineering Contradiction:
ImprovecostVSAvoiddetectable displacement range
Core Design Contradiction:
Ease of manufactureVSLength of stationary object

Solution Approach 1:

Magnetic concentrators serve as mediators that transform the limited magnetic field of a monopole magnet into an extended field. The concentrators are positioned between the monopole magnet and detection elements to redirect and extend the magnetic flux, enabling detection over a range larger than the detection element pitch

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The invention extends the magnetic field detection in additional spatial dimensions by strategically positioning magnetic concentrators around the monopole magnet. This creates magnetic field extensions in multiple directions, effectively increasing the detectable displacement range beyond the single-pitch limitation

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

3Length of stationary object

If magnetic detection elements are arranged in pairs with magnetic concentrators, then the detectable range is extended, but the sensor structure becomes more complex

Engineering Contradiction:
Improvedetectable displacement rangeVSAvoidsensor structure
Core Design Contradiction:
Length of stationary objectVSDevice complexity

Solution Approach 1:

The sensor structure is segmented into multiple magnetic detection elements arranged in pairs, each associated with specific magnetic concentrators. This segmentation allows each element pair to detect magnetic field changes in specific regions, collectively extending the overall detectable range while maintaining manageable complexity through modular arrangement

Inventive Principle:
Principle #1Segmentation

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

The solution enables wider detectable ranges and reduced noise interference, effectively utilizing monopole magnets to enhance displacement detection capabilities.

Implementation Method 1

magnetic concentrators which convert a magnetic flux in a second direction orthogonal to the one direction and the first direction into a magnetic flux in the first direction

Methodology Applied
Scientific EffectMagnetic flux conversion: Magnetic Field

Implementation Method 2

magnetic detection element groups, which detect a magnetic flux density of a magnetic field formed by the magnet

Methodology Applied
Scientific EffectMagnetic field detection: Hall Effect

Data Source

PatentEP3273202B1Displacement detection device
Publication Date: 2020.04.22 MELEXIS TECHNOLOGIES SA
  • EP3273202B1 patent drawingFigure 1
  • EP3273202B1 patent drawingFigure 2A~2B
  • EP3273202B1 patent drawingFigure 3A~3B

AI summary

Provided is a displacement detection device which reduces the influence of disturbance noise on a magnetic field to be detected and makes a range detectable by a monopole magnet wider than a pitch of a magnetic detection elements. A displacement detection device 3 includes a magnet 2 which is displaced in a displacement direction Ds, is rod-shaped and has a form in which a longitudinal direction and the displacement direction Ds form a predetermined angle θ, and a sensor IC 1 in which magnetic detection element groups, which detect a magnetic flux density of a magnetic field formed by the magnet 2 in an x direction and a z direction orthogonal to the displacement direction Ds, are arranged in pairs with a predetermined interval dp, and which outputs a difference between outputs of the magnetic detection element groups.