Four-Point Link Suspension With Torsion Bar for E-Axle Packaging
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing parallelogram rear air suspension systems in vehicles with e-axles face challenges in accommodating the drive unit due to dynamic movements, leading to roll stiffness that affects mobility, vehicle comfort, and handling, particularly when combined with an e-axle design.
Innovation Solution
A four-point link suspension system with tapered side link arms and a torsion bar, allowing for improved management of lateral and twisting movements, incorporating an e-axle with a front-mounted drive unit, and enhancing vehicle stability and comfort.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Stability of the object's composition
If a stabiliser bar or beam is used to constitute both torque rod and stabiliser functions, then the stabilising function becomes very roll stiff, but this does not allow the lateral movement a high positioned roll centre imposes, negatively impacting mobility, vehicle comfort and handling
Solution Approach 1:
The stabilisation frame is divided into separate link arms (first and second link arms) connected by a torsion bar, rather than using a single rigid stabiliser bar. This segmentation allows each component to perform its specific function independently while working together to provide both stabilisation and lateral movement capability.
Solution Approach 2:
The torsion bar provides controlled rotational stiffness that can be adjusted through its design parameters (material, diameter, length, wire diameter). This allows the suspension to provide sufficient roll stiffness for stability while maintaining enough flexibility to accommodate lateral movements required by high positioned roll centres.
2Stability of the object's composition
If a parallelogram rear air suspension with four air springs is used, then the caster remains virtually constant as the axle moves vertically, but it is problematic to accommodate an e-axle drive unit between the front air springs considering dynamic movements
Solution Approach 1:
The suspension system is designed to accommodate dynamic movements of the axle while maintaining caster stability. The link arms and torsion bar configuration allows the system to adapt to varying positions and movements, creating sufficient space for the e-axle drive unit even during dynamic operation.
Solution Approach 2:
The design moves the drive unit mounting to the front of the axle in a different spatial arrangement, utilizing space in another dimension rather than trying to fit it between the air springs in the traditional configuration. This dimensional repositioning resolves the space conflict while maintaining suspension functionality.
3Ease of operation
If the side link arms are tapered towards the first ending, then lateral and twisting movements are managed better, but the structure becomes more complex
Solution Approach 1:
The link arms feature local tapering specifically at the first ending where connection to the vehicle frame occurs, rather than uniform complexity throughout. This localized geometric modification provides improved movement management precisely where needed at the connection point, while keeping other portions of the structure simpler.
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 suspension system provides enhanced vehicle comfort, improved handling, and increased space for components like the e-axle drive unit, reducing the risk of cargo displacement and passenger injury, while allowing higher-speed maneuvering.
Implementation Method 1
a torsion bar, connecting the first side link arm and the second side link arm
Implementation Method 2
a first side suspension spring, configured to absorb a vertical load and a second side suspension spring, configured to absorb the vertical load
Data Source
Figure 1
Figure 2A
Figure 2B
AI summary
A four point link suspension (200) for a vehicle (100); the suspension (200) comprises: a first side suspension spring (210a), configured to absorb a vertical load; a second side suspension spring (210b), configured to absorb the vertical load; wherein the springs (210a, 210b) are configured to be connected to a vehicle frame (220a, 220b) via a respective joint (312a, 312b); a stabilisation frame (300), comprising a first side link arm (310a) having a first ending (311a) and a second ending (313a) connected to the first side suspension spring (210a) via a second joint (315a); a second side link arm (310b) and a second ending (313b) connected to the second side suspension spring (210b) via a second joint (315b); a torsion bar (320), connecting the side link arms (310a, 310b); which side link arms (310a, 310b) are tapered towards the respective first ending (311a, 311b).