Torque Sensor Stator Tooth Layout Against External Magnetic Interference
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing torque sensors in electronic power steering systems are affected by external magnetic fields, leading to inaccurate measurement of torsion in the steering shaft due to interference with the magnetic flux of Hall integrated circuits.
Innovation Solution
A sensing device with a stator and rotor configuration, where the stator teeth are designed with specific geometries and overlapping structures to minimize the impact of external magnetic fields, and a collector is placed between the stator teeth to further reduce interference.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a collector is disposed at an outer side of the stator teeth in a magnetic type torque sensor, then the torque sensor can measure torque, but the collector serves as a path for external magnetic fields, affecting the magnetic flux value of the Hall IC and causing measurement inaccuracies
Solution Approach 1:
The patent removes the collector component entirely from the torque sensor structure. Instead of using a collector to guide magnetic flux, the invention uses a magnetic shield disposed between the stator teeth and the rotor to block external magnetic fields, thereby eliminating the source of measurement errors while maintaining torque measurement capability through alternative means
Solution Approach 2:
The patent introduces a magnetic shield as an intermediary component between the stator teeth and the rotor. This magnetic shield acts as a mediator that blocks external magnetic fields from reaching the Hall IC, thereby protecting the measurement system without requiring a collector that would itself become a magnetic field path
2Measurement precision
If multiple collectors are used to maintain accurate torque measurement in the presence of external magnetic fields, then measurement accuracy can be maintained, but the device complexity and number of components increase
Solution Approach 1:
The patent removes the collector component entirely from the torque sensor structure. Instead of using a collector to guide magnetic flux, the invention uses a magnetic shield disposed between the stator teeth and the rotor to block external magnetic fields, thereby eliminating the source of measurement errors while maintaining torque measurement capability through alternative means
Solution Approach 2:
The patent introduces a magnetic shield as an intermediary component between the stator teeth and the rotor. This magnetic shield acts as a mediator that blocks external magnetic fields from reaching the Hall IC, thereby protecting the measurement system without requiring a collector that would itself become a magnetic field path
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 solution effectively inhibits magnetic field interference from external sources, allowing for accurate torque measurement and reducing the number of collectors required, resulting in a simplified and more reliable sensing device.
Implementation Method 1
a structure in which the collector is disposed at an outer side of the stator teeth... affecting a magnetic flux value of a Hall integrated circuit (IC)
Data Source
AI summary
An embodiment may provide a sensing device comprising: a stator comprising stator teeth; and a rotor comprising magnets, wherein: the stator teeth comprise a first stator tooth and a second stator tooth arranged to overlap the first stator tooth in the radial direction from the center of the stator; the first stator tooth comprises multiple first teeth and multiple third teeth, and the second stator tooth comprises multiple second teeth; one of the multiple first teeth is arranged to overlap one of the multiple second teeth in the radial direction; and the magnets are disposed between the multiple first teeth and the multiple third teeth, respectively.