Magnetic Resistance Sensor Redundancy for Electric Power Steering
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The high cost of using multiple resolvers to detect the rotation angle of a motor in electric actuator products, which increases production costs while aiming to ensure reliability through redundant configurations.
Innovation Solution
A rotation angle sensor configuration using a magnet, a circuit board with multiple magnetic resistance sensor elements, and a support member, where the circuit board is fixed between the support member and the motor to detect the rotation angle, allowing for a redundant detection at a lower cost.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If multiple resolvers are used to detect the rotation angle of a motor in redundant configuration, then the reliability is improved, but the production cost increases
Solution Approach 1:
The patent uses magnetic resistance sensor elements as inexpensive copies or alternatives to expensive resolver sensors. Multiple magnetic resistance sensors are mounted on the circuit board to detect the rotation angle of the motor, providing redundant detection capability without the high cost of multiple resolvers. This principle of using simpler, cheaper sensing elements achieves the same functional goal at lower cost.
Solution Approach 2:
The patent employs magnetic resistance sensor elements that are significantly cheaper than resolvers. These sensors are mounted directly on the circuit board in a simplified configuration, accepting their role as cost-effective, shorter-lived components that still provide the necessary redundant detection function for reliability.
2Reliability
If multiple expensive resolvers are mounted, then the redundant detection capability is improved, but the device complexity increases
Solution Approach 1:
The patent merges multiple magnetic resistance sensor elements onto a single circuit board, integrating them into one compact unit. This consolidation provides redundant detection capability while reducing the overall device complexity compared to mounting multiple separate resolver units. The sensors share common mounting and signal processing infrastructure on the same circuit board.
Solution Approach 2:
The circuit board serves multiple functions: it provides the mounting structure for the magnetic resistance sensors, supplies electrical connections to all sensors, and integrates the signal processing circuitry. This multi-functional design reduces device complexity by eliminating the need for separate components for each sensing function.
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
This configuration enables simultaneous detection of a motor's rotation angle by multiple sensors at a lower cost, maintaining reliability while reducing production expenses.
Implementation Method 1
a plurality of magnetic resistance sensor elements, which detect magnetic flux
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A rotation angle sensor including: a magnet (10) fixed to an end (5) on an opposite side to an output end (4) of a rotation shaft (3) of a motor (2); a circuit board (11) on which a plurality of magnetic resistance sensor elements (20, 21) are mounted; and a support member (12) fixed to the motor (2), wherein the circuit board (11) is arranged between the support member (12) fixed to the motor (2) and the motor (2) and is fixed to the support member (12) in such a way that the plurality of magnetic resistance sensor elements (20, 21) come close to the magnet (10).