Thermally Insulated Wheel Speed Sensor for Utility Vehicle Brakes
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Wheel speed sensors in utility vehicles face significant thermal stress due to higher peak temperatures during braking, which exceeds the tolerance of existing Hall sensors, making them unreliable in high-temperature environments.
Innovation Solution
A wheel speed sensor design featuring a housing with thermal insulation and an AMR sensor, which includes a protective cap with cavities filled with air or another gas to reduce thermal conductivity, and an active pulse sensor to detect magnetic field changes, ensuring functionality and extended lifespan in high-temperature conditions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If Hall sensors are used in utility vehicle wheel speed sensors, then the sensor can detect wheel speed, but the sensor cannot withstand the high thermal stress from braking temperatures
Solution Approach 1:
The patent introduces a thermal barrier as an intermediary element between the Hall sensor and the high-temperature environment. This thermal barrier mediates the thermal stress by blocking direct heat transfer to the sensor, allowing the sensor to operate reliably in the high-temperature environment of utility vehicle brakes.
Solution Approach 2:
The patent employs a disposable thermal barrier that can be easily replaced. This component is designed to withstand the thermal stress and can be discarded when degraded, protecting the more expensive and durable Hall sensor from direct exposure to extreme temperatures.
2Adaptability or versatility
If active wheel speed sensors are used in utility vehicles, then diagnostic functions and data protocols can be implemented, but the sensor fails under high peak temperatures during braking
Solution Approach 1:
The thermal barrier serves as a protective intermediary that enables the active sensor with its diagnostic capabilities to function in high-temperature environments. By blocking thermal stress, it allows the sensor to maintain its electronic functionality and diagnostic features without failure.
Solution Approach 2:
The patent changes the thermal parameters of the sensor environment by introducing the thermal barrier, which modifies the temperature profile reaching the sensor. This parameter change allows the active sensor to operate within its specified temperature range despite the high external temperatures during braking.
3Measurement precision
If wheel speed sensors are placed in the wheel hub region for direct detection, then accurate wheel speed detection is achieved, but the sensor is exposed to high thermal stress
Solution Approach 1:
The thermal barrier acts as a mediator between the sensor and the high-temperature wheel hub environment. It allows the sensor to maintain its precise measurement capability while protecting it from thermal damage by blocking the harmful thermal stress.
Solution Approach 2:
The patent applies local quality protection by placing the thermal barrier specifically at the interface between the sensor and the high-temperature environment. This localized protection maintains measurement precision in the detection region while shielding the sensor components from thermal stress.
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 allows wheel speed sensors to operate reliably in high-temperature environments, enabling accurate wheel speed detection, rotational direction recognition, and additional diagnostic functionalities while protecting heat-sensitive components from peak temperatures.
Implementation Method 1
The wheel speed sensor has a region between the active pulse sensor and an environment of the wheel speed sensor, which region has a thermal insulation medium that has a lower thermal conductivity than a thermal conductivity of a material of the housing
Implementation Method 2
The active pulse sensor is a sensor which detects pulses which are generated by a change of a magnetic field in a detection region of the sensor
Data Source
AI summary
A wheel speed sensor for a utility vehicle, including: an active pulse sensor, a housing to at least partially enclose the active pulse sensor, and a protective cap to at least partially cover the housing; in which the wheel speed sensor has at least one component to adapt a temperature resistance capability of the wheel speed sensors so that the wheel speed sensor is usable in a high temperature environment.