Split-Ring Wheel Bearing Assembly for Stable Preload
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In wheel bearing assemblies, the preload variation due to temperature expansions and material differences between the bearing unit and wheel hub complicates the installation and increases costs, as precise pairing and measurement are required to achieve optimal bearing clearance and service life.
Innovation Solution
A multi-row bearing assembly with a two-part ring and an elastic element in the gap between the ring parts, allowing for elastic compensation of dimensional differences and independent preload adjustment, eliminating the dependence on press fit tolerances and enabling optimal bearing friction and service life.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If the bearing unit is preassembled and preloaded at the factory with precise bearing clearance, then the installation is simplified and sufficient to attach using an axle nut, but the preload variation increases when the bearing unit and wheel hub have different temperature expansions due to material differences
Solution Approach 1:
The bearing assembly is divided into a bearing unit and a hub unit that can be manufactured separately with different materials. The bearing unit contains the bearing rings, rolling elements, and seal assembly, while the hub unit contains the press-fit outer ring. This segmentation allows each component to be optimized for its specific material requirements and thermal expansion characteristics.
Solution Approach 2:
A press-fit outer ring acts as an intermediary component between the bearing unit and the hub. This outer ring is pressed into the hub and provides a controlled interface that decouples the thermal expansion differences between the bearing unit (steel) and the hub (aluminum or other materials), preventing direct thermal interaction and maintaining preload stability.
2Weight of moving object
If the bearing unit and wheel hub are made from materials with different thermal expansion coefficients, then weight reduction is achieved, but the preload variation increases due to temperature expansions
Solution Approach 1:
Different materials are used in different locations: the bearing unit is made from steel with low thermal expansion for precision and load-bearing, while the hub can be made from aluminum or other lightweight materials with higher thermal expansion for weight reduction. The press-fit outer ring serves as a transition zone that manages the thermal expansion mismatch between these dissimilar materials.
Solution Approach 2:
The design explicitly accounts for thermal expansion differences by using materials with different coefficients of thermal expansion in the bearing unit and hub, and managing these expansions through the press-fit outer ring interface. This allows the system to accommodate thermal growth without generating harmful preload variations.
3Manufacturing precision
If precise pairing and measurement of bearing units and wheel hubs are performed at the factory, then the bearing clearance and service life are optimized, but the manufacturing complexity and costs increase
Solution Approach 1:
The bearing unit is preassembled with the bearing rings, rolling elements, and seal assembly at the factory in a controlled environment. This preliminary assembly allows for precise bearing clearance setup without requiring complex field adjustments. The press-fit outer ring is also pre-prepared with the correct interference fit dimensions, enabling straightforward installation.
Solution Approach 2:
The design changes the critical parameters from bearing clearance (which requires precise pairing) to press-fit interference dimensions. By controlling the press-fit outer ring dimensions and interference fit values, the system achieves reliable installation without requiring complex bearing-to-hub pairing measurements, simplifying the manufacturing process.
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 reduces preload variation, improves bearing friction control, and allows for optimal installation without factory presetting, leading to reduced fuel consumption and CO2 emissions by enabling the use of components with different thermal expansion coefficients.
Implementation Method 1
an elastic element is disposed in the gap, which elastic element is configured to fill the gap. The elastic element makes it possible in particular to elastically compensate for differences in the dimensions of the bearing rings and/or the components.
Data Source
AI summary
A bearing assembly includes a stationary component, a rotatable component and a preloadable double row bearing unit having a rotatable bearing ring and a stationary bearing ring and two rows of rolling elements between the rings. The rotatable bearing ring and/or the stationary bearing ring includes a first part and a second part, and the first part is spaced from the second part by a gap so that the first part and the second part do not touch. At least one elastic element is disposed in the gap and fills the gap.