Torque Sensor Collector Unit Magnetic Flux Leakage Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional contactless torque sensors for electric power steering systems face issues with complexity, high manufacturing costs, and durability due to the large number of constituent elements, as well as leakage magnetic flux problems.
Innovation Solution
A torque sensor device with a simplified structure that includes a housing, a magnet unit, a collector unit, and a sensing unit, where the collector unit is designed to minimize magnetic flux leakage and maximize transfer to the sensing unit, using a magnet ring or block with a focused magnetic field detected by a torque sensor at the outer circumference of the collector unit.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a conventional contactless torque sensor uses multiple tooth rings and permanent magnets interlaced together, then the magnetic field can be generated for detection, but the leakage magnetic flux increases and the device complexity increases
Solution Approach 1:
The patent extracts and eliminates unnecessary tooth rings from the conventional structure. Instead of using multiple interlaced tooth rings with permanent magnets, the invention uses a single tooth ring structure where the permanent magnet is positioned alone, removing redundant components that caused complexity and assembly difficulties while maintaining the essential magnetic field generation function
Solution Approach 2:
The patent merges the functions of multiple tooth rings into a single integrated tooth ring structure. The single tooth ring combines the magnetic field generation and detection functions that were previously distributed across multiple separate components, simplifying the overall structure while maintaining detection capability
2Measurement precision
If a conventional torque sensor uses multiple interlaced tooth rings and permanent magnets, then magnetic field detection is enabled, but the leakage magnetic flux increases causing interference
Solution Approach 1:
The patent removes the source of leakage magnetic flux by eliminating the multiple interlaced tooth rings structure. The single tooth ring design with properly positioned permanent magnet prevents magnetic flux leakage while maintaining the necessary magnetic field for detection, thus removing the harmful interference effect
Solution Approach 2:
The patent converts the magnetic field configuration from a harmful leakage pattern to a beneficial focused pattern. By repositioning the permanent magnet and using a single tooth ring, the magnetic flux that would have leaked is now concentrated and directed properly for detection, turning potential interference into useful detection signal
3Reliability
If a conventional torque sensor uses an excessive number of constituent elements, then the detection function is achieved, but the manufacturing cost increases and assembly process becomes complicated
Solution Approach 1:
The patent extracts and removes unnecessary components from the conventional design. By eliminating redundant tooth rings and simplifying the permanent magnet arrangement, the invention reduces the number of parts that need to be manufactured and assembled, directly lowering manufacturing cost and assembly complexity while preserving detection functionality
Solution Approach 2:
The patent merges multiple separate components into fewer integrated elements. The single tooth ring structure replaces multiple interlaced tooth rings, reducing the number of assembly steps and manufacturing operations required, thereby improving ease of manufacture while maintaining detection reliability
4Reliability
If a conventional torque sensor uses many constituent elements, then the detection capability is provided, but the durability period is reduced due to more potential failure points
Solution Approach 1:
The patent removes excess components that create potential failure points. By eliminating redundant tooth rings and simplifying the structure to essential elements only, the invention reduces the number of parts that can fail, thereby extending the durability period while maintaining the necessary detection capability
Solution Approach 2:
The patent combines multiple separate components into fewer integrated elements, reducing the total number of interfaces and connection points that could fail over time. This merging approach maintains detection capability while improving long-term durability by minimizing potential failure sources
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 enhances detection accuracy, reduces manufacturing costs, and improves durability by minimizing material usage and optimizing the magnetic field transfer, resulting in a more reliable and cost-effective torque sensing system.
Implementation Method 1
a magnet unit (200) rotatably accommodated in the housing (100) in such a manner as to be connected to one end of one of the input shaft (2) and the output shaft (3)... a collector unit (300) rotatably accommodated in the housing (100) in such a manner as to be at least partially connected to one end of the other of the input shaft (2) and the output shaft (3), the collector unit (300) being configured to form a magnetic circuit together with the magnet unit (200)... a sensing unit (400) including a torque sensor disposed at the outer circumference of the collector unit (300) and configured to detect a magnetic field focused by the collector unit (300)
Implementation Method 2
the collector unit (300) being configured to form a magnetic circuit together with the magnet unit (200)... to detect a magnetic field focused by the collector unit (300)
Data Source
AI summary
Provided is a torque sensor device to detect a torque between an input shaft and an output shaft through a relative rotation displacement therebetween. The torque sensor device includes: a housing to accommodate an end of the input shaft and an end of the output shaft: a magnet unit rotatably accommodated in the housing to be connected to one end of one of the input shaft and the output shaft; a collector unit rotatably accommodated in the housing to be connected to one end of the other of the input shaft and the output shaft, the collector unit forming a magnetic circuit together with the magnet unit; and a sensing unit including a torque sensor disposed at the outer circumference of the collector unit and configured to detect a magnetic field focused by the collector unit. The collector unit includes a lower collector including an annular lower collector ring.