Vehicle Wheel Speed Sensor with Segmented Clamping Bush
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing wheel speed sensors for vehicles face issues with axial displacement due to temperature fluctuations and vibrations, leading to increased air gaps between the sensor head and pole wheel, which can result in inaccurate readings and potential damage.
Innovation Solution
A rod-shaped sensor device with a non-ferromagnetic metal carrier structure, filled with plastic, featuring interrupted metallic surface areas and resilient tongue clamping mechanism, allowing for precise positioning and stable attachment within a conventional clamping bush, enabling axial displacement without damage and maintaining contact during temperature changes.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If the sensor device is held in the clamping bush by frictional force, then the sensor device can be easily installed, but the sensor device can be displaced axially due to temperature fluctuations and vibrations
Solution Approach 1:
The clamping bush is divided into two functional zones: an upper frictional holding zone for easy installation and positioning, and a lower claw engagement zone for secure anti-displacement holding. This segmentation allows the single clamping bush to provide both easy installation and reliable position stability.
Solution Approach 2:
The clamping bush incorporates resilient (elastic) claws that can dynamically adapt to temperature fluctuations and vibrations. These claws engage with axial grooves in the sensor device, providing a mechanical interlock that maintains secure holding while accommodating dynamic environmental conditions.
2Reliability
If the sensor device is clamped securely to prevent displacement, then position stability is improved, but the sensor device may be damaged when the magnet wheel runs in opposite directions
Solution Approach 1:
The resilient claws in the clamping bush are made of elastic material that can flex and yield under load. When the magnet wheel runs in opposite directions or experiences reverse forces, these claws can deform elastically to absorb the shock, preventing damage to the sensor device while maintaining secure holding through the claw-groove engagement.
3Measurement precision
If the air gap between sensor head and pole wheel is minimized for accurate detection, then measurement precision is improved, but the sensor device becomes more sensitive to temperature-induced migration
Solution Approach 1:
The clamping bush creates two distinct holding mechanisms: upper frictional holding for initial positioning and lower claw-groove mechanical interlocking for secure fixation. This segmentation ensures the sensor device maintains its precise position relative to the pole wheel while being resistant to temperature-induced migration, as the claw-groove engagement provides rigid positional constraint.
Solution Approach 2:
The sensor device is pre-positioned in the upper frictional holding zone during installation, allowing for easy adjustment to achieve the optimal air gap for accurate measurement. Once positioned, the lower resilient claws engage with the axial grooves to lock the sensor device in place, preventing subsequent migration due to temperature changes while maintaining the precisely set air gap.
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 ensures stable and accurate wheel speed detection, even under mechanical vibrations and temperature fluctuations, with improved manufacturing efficiency and compatibility with existing systems, while maintaining sensor longevity and precise positioning.
Implementation Method 1
The clamping bushing has resilient tongues that lie against the sensor device and press it onto opposing tongues
Implementation Method 2
the support structure is filled with a casting compound, for example a plastic
Data Source
Figure 1~2
Figure 3
Figure 4
AI summary
The invention relates to a sensor apparatus 2 for detecting a wheel speed of a vehicle. The sensor apparatus 2 has a rod-shaped sensor carrier 4 and a sensor 6 which is introduced into the sensor carrier 4 and, in order to detect the wheel speed, senses the rotation of a rotor rotating together with the wheel. According to the invention, the sensor apparatus 2 has a carrier structure 8 for accommodating the sensor 6 and a potting compound 12 for filling the sensor carrier 4. The surface, in particular the lateral surface, of the sensor carrier 4 is formed by a plurality of interrupted, metal surface areas of the carrier structure 8 and areas filled with the potting compound 12, wherein at least two metal surface areas are in the form of contact surfaces 22. The invention also relates to a sensor arrangement, to a wheel speed detection system for a vehicle and to the vehicle having the sensor apparatus 2 and to a method for producing the sensor apparatus 2 and to the use of the sensor apparatus 2 for detecting the wheel speed.