Magnetic Field Sensor for Shaft Rotation Detection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for sensing the rotation of a shaft, such as using ferromagnetic toothed wheels, are inefficient and costly, requiring complex algorithms and significant space, and are sensitive to manufacturing accuracy and mounting precision.
Innovation Solution
A sensor device comprising a magnetic field sensitive element and electronic circuitry that senses the orientation angle of a magnetic field on a shaft, generating signals with a 90° phase shift to accurately determine the orientation and speed of the shaft, allowing for efficient and accurate rotation sensing without the need for toothed wheels.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a ferromagnetic toothed wheel is used for sensing rotation, then rotation speed and angular position can be detected, but the device complexity and space requirements increase significantly
Solution Approach 1:
The patent extracts the rotation sensing function from the complex toothed wheel mechanism and implements it using a simple magnet mounted on the rotating shaft. The magnetic field sensitive element detects the magnet's position and speed, eliminating the need for ferromagnetic toothed wheels while maintaining measurement precision.
Solution Approach 2:
The patent replaces the mechanical toothed wheel system with a magnetic field-based sensing system. Instead of using mechanical teeth and radial sensors, a magnet and magnetic field sensitive element are used, substituting mechanical complexity with a simpler magnetic field interaction approach.
2Measurement precision
If a ferromagnetic toothed wheel is used for sensing rotation, then rotation speed and angular position can be detected, but manufacturing accuracy and mounting precision requirements increase
Solution Approach 1:
The patent removes the toothed wheel component entirely and extracts the essential rotation detection function, implementing it through a magnet and magnetic field sensor. This eliminates the need for precise toothed wheel manufacturing while maintaining measurement accuracy.
Solution Approach 2:
The patent changes the sensing parameter from mechanical tooth geometry to magnetic field characteristics. By using the magnet's magnetic field instead of physical tooth profiles, the system becomes less sensitive to manufacturing tolerances and mounting precision requirements.
3Measurement precision
If a ferromagnetic toothed wheel is used for sensing rotation, then rotation information can be obtained, but costs increase due to space and complexity requirements
Solution Approach 1:
The patent extracts the rotation sensing capability from the expensive toothed wheel assembly and implements it using inexpensive magnet and magnetic field sensitive element components, significantly reducing material and manufacturing costs while maintaining measurement precision.
Solution Approach 2:
The patent uses simple, inexpensive magnet and sensor components instead of costly toothed wheels. These components are easier and cheaper to manufacture, making the overall system more cost-effective while achieving the same measurement precision.
4Measurement precision
If complex algorithms are used to estimate rotation angle from pulse patterns, then angular position accuracy can be improved, but device complexity and processing requirements increase
Solution Approach 1:
The patent replaces complex signal processing algorithms with direct magnetic field sensing. The magnetic field sensitive element provides direct position and speed information without requiring complex pulse pattern analysis, reducing computational complexity while maintaining angular position accuracy.
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 provides accurate and efficient rotation sensing, reducing complexity, space requirements, and costs, while maintaining high accuracy and compatibility with existing systems.
Implementation Method 1
a magnetic field sensitive element to be positioned in a magnetic field of a magnet positioned on an end face of a shaft, the magnetic field sensitive element being configured to sense an orientation angle of the magnetic field
Data Source
AI summary
A sensor device is provided with a magnetic field sensitive element being positioned in a magnetic field of a magnet. The magnetic field sensitive element is configured to sense an orientation angle of the magnetic field in the range between 0° and 360° and generate a sensing signal. The electronic circuitry is configured to receive and process the sensing signal from the magnetic field sensitive element to generate an angle signal indicating the orientation angle of the magnetic field and an angular speed of the shaft.