Non-Oval Magnetic Sensor Geometry to Reduce Hysteresis
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Magnetic sensors exhibit hysteresis, which worsens precision by causing discrepancies in output between increasing and decreasing external magnetic fields.
Innovation Solution
The magnetic sensor is designed with an elongate element portion having a magnetically sensitive axis along its short axis, arranged in a non-oval shape within an imaginary ellipse, with soft magnetic bodies on both sides to shield external magnetic fields, reducing hysteresis and enhancing precision.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If the element portion is made elongate with magnetoresistive effect to detect magnetic field changes, then the sensitivity in the direction of the magnetically sensitive axis is improved, but hysteresis occurs causing precision deterioration
Solution Approach 1:
The element portion is designed with an asymmetric non-oval shape that can be arranged in an imaginary ellipse, where the major axis connects both ends along the long axis direction and the minor axis connects both ends along the short axis direction. This asymmetric geometry modifies the magnetic field distribution and magnetization patterns, reducing hysteresis effects while preserving sensitivity along the short axis (magnetically sensitive axis). The asymmetric shape creates more uniform magnetic field lines and reduces unstable magnetic field components that cause hysteresis.
2Measurement precision
If soft magnetic thin films are arranged on both sides of the giant magnetoresistive thin film to shield magnetic fields, then the sensitivity in the direction of the magnetically sensitive axis is enhanced, but device complexity increases
Solution Approach 1:
Soft magnetic bodies are strategically positioned on both sides of the element portion along the long axis direction, creating localized magnetic field shielding zones. This local quality approach enhances the magnetic field sensitivity along the short axis (magnetically sensitive axis) by shielding unwanted magnetic field components from directions other than the sensitive axis, while maintaining a relatively simple overall device structure. The soft magnetic bodies are positioned to provide targeted shielding without requiring complex multi-layer configurations.
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 design reduces hysteresis, leading to more precise output by minimizing unstable magnetic field components and improving sensitivity.
Implementation Method 1
a magnetic sensor that has an element having magnetoresistive effect
Implementation Method 2
the soft magnetic thin films that are arranged on both sides of the giant magnetoresistive thin film improves the performance of shielding a magnetic field
Data Source
AI summary
The magnetic sensor of the invention has an element portion that is elongate, that exhibits magnetoresistive effect and that has a magnetically sensitive axis in a direction of a short axis thereof. The element portion is non-oval and can be arranged in an imaginary ellipse, wherein the imaginary ellipse has a major axis that connects both ends of the element portion with regard to a direction of a long axis thereof to each other and a minor axis that connects both ends of the element portion with regard to a direction of the short axis thereof to each other, as viewed in a direction that is perpendicular both to the short axis and to the long axis of the element portion.