Sensing Device With Segmented Collector For Position Detection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing sensing devices for electric power steering systems face challenges with nonlinear magnetic flux density changes and increased manufacturing costs due to complex components, which affect accuracy and are influenced by external magnetic fields.
Innovation Solution
A sensing device design featuring a magnet with collectors and sensors arranged to minimize magnetic leakage, where the collectors have varying gap sizes and orientations to enhance position detection accuracy, and the sensors detect magnetic flux density differences to determine the magnet's position, reducing component complexity and external field influence.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a traditional sensing device with multiple coils and a tube is used to detect rack bar position, then the device can measure steering angle, but magnetic flux density changes nonlinearly and manufacturing costs increase due to many components
Solution Approach 1:
The collector is divided into multiple legs (first leg part and second leg part) with gaps between them, creating a segmented structure that simplifies the overall device while maintaining detection capability. This segmentation allows the magnetic field to be detected through the gaps without requiring a complete enclosed tube structure.
Solution Approach 2:
The invention extracts the essential function of position detection from the complex multi-coil system and implements it through a simpler collector-sensor arrangement. The tube structure is removed entirely, replacing it with a collector that has gaps, thereby reducing component count while preserving the core sensing function.
2Measurement precision
If a traditional sensing device with multiple coils and a tube is used to detect rack bar position, then the device can measure steering angle, but magnetic flux density changes nonlinearly
Solution Approach 1:
The gaps between the collector legs are strategically positioned and dimensioned to optimize magnetic field detection. The local geometry of the gaps (including their width and spacing) is specifically designed to create a linear relationship between magnet position and detected magnetic flux density, improving measurement linearity throughout the detection range.
Solution Approach 2:
The invention transitions from a three-dimensional enclosed tube structure to a planar collector configuration with gaps. This dimensional simplification allows for better control of magnetic flux paths and improves linearity by eliminating the nonlinear effects introduced by the curved tube walls and multiple coil windings.
3Measurement precision
If collectors with varying gap sizes are used to reduce magnetic leakage, then position measurement accuracy improves, but device complexity increases
Solution Approach 1:
The collector legs are designed with asymmetric gap configurations where different gaps have different sizes. This asymmetry is intentional and optimized to compensate for magnetic field distribution variations, reducing magnetic leakage effects while maintaining a relatively simple single-piece collector structure rather than requiring multiple complex components.
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 proposed sensing device improves accuracy by reducing magnetic leakage and external field interference while simplifying components, leading to more precise position measurement and lower manufacturing costs.
Implementation Method 1
A sensing device includes a magnet, a first collector disposed to correspond to a path through which the magnet moves
Implementation Method 2
the sensing device can detect the position of the rack bar using an inductive magnetic field between the coils and the magnet
Data Source
AI summary
An embodiment provides a sensing device comprising: a magnet; a first collector disposed to correspond to a path along which the magnet moves; and a first sensor disposed at one side of the first collector, wherein the first collector comprises a first leg part and a second leg part, the first leg part and the second leg part each comprise a facing surface disposed to face the magnet, and the sensing device comprises an area in which a gap between the first leg part and the second leg part increases along a direction from one side toward the other side thereof or an area in which the facing surface of each of the first leg part and the second leg part has a width decreasing along a direction from one side toward the other side thereof. Accordingly, the sensing device can reduce an effect of an external magnetic field to improve sensing accuracy.