U-Shaped Magnet Sensor for Vehicle Seat Position Monitoring
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Modern passenger vehicles face challenges in implementing advanced safety systems, particularly in ensuring competitive pricing while incorporating adaptive airbag systems that adjust deployment based on seat position relative to the instrument panel, which requires effective monitoring of seat positions.
Innovation Solution
A magnetic sensing device utilizing a U-shaped magnet with specific flux regions to detect the presence of ferromagnetic materials, enabling the activation of control signals for seat position monitoring in vehicle systems, including a sensor assembly within a housing on a sliding rail that generates distinct magnetic flux areas to sense movement between positions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a magnetic sensing device uses a larger magnet to generate stronger magnetic flux for reliable detection, then the sensing reliability is improved, but the device size and cost increase
Solution Approach 1:
The magnetic sensing device is divided into two functional sections: a first section with a sensor that detects magnetic flux changes, and a second section with a ferromagnetic target that modifies the magnetic field. This segmentation allows the use of a smaller magnet while maintaining reliable detection through the interaction between the two sections.
Solution Approach 2:
A ferromagnetic target is introduced as an intermediary element between the magnet and the sensor. This target modifies the magnetic flux distribution, creating detectable changes in the magnetic field that enhance the sensing signal without requiring a larger magnet.
2Ease of manufacture
If the magnet is made smaller to reduce device cost and size, then manufacturing cost is reduced, but the magnetic flux generation capability deteriorates
Solution Approach 1:
The ferromagnetic target acts as a magnetic flux concentrator and modifier, enhancing the magnetic field interaction without requiring a larger magnet. This intermediary element amplifies the effect of the smaller magnet, maintaining sufficient magnetic flux generation capability while reducing material costs.
Solution Approach 2:
The invention changes the magnetic circuit parameters by introducing the ferromagnetic target with specific permeability properties. This modifies the magnetic flux distribution and density in the sensing region, compensating for the reduced magnet size while maintaining detection effectiveness.
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 magnetic sensing device accurately detects the presence of ferromagnetic materials, allowing for precise seat position monitoring and enabling adaptive airbag deployment adjustments, thereby enhancing safety systems while potentially reducing costs through smaller magnet usage.
Implementation Method 1
The magnet generates a first region of low or no magnetic flux in the region of the sensor above the distal plane of the magnet
Data Source
AI summary
A magnetic sensing device including a U-shaped magnet with a pair of legs and a base defining a first interior channel and a distal plane. A sensor assembly in the first interior channel includes a sensor that extends above the distal plane. The magnet generates a first region of low or no flux above the distal plane in a first position of the magnet, a second region of low or no magnetic flux in the interior channel in a second position of the magnet, and a third region of magnetic flux above the distal plane in the second position of the magnet which causes the sensor to activate a control signal. The base includes steps and a second interior channel that opens into the first interior channel.