Link Assembly with Offset Axes for Suspension Compliance

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional single bushing pivot arrangements in vehicle suspension assemblies limit the differential travel distance and rate, leading to compromised steering response, ride harshness, and shock absorber efficiency, while complex bushing geometries increase costs and reduce durability.

Innovation Solution

A link assembly with separate first and second bushing assemblies, where the first axis and second axis are spaced by an offset distance and extend in different non-parallel directions, allowing for greater travel distance and spring rate differentials without the cost and durability penalties of complex geometries.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of operation

If complex bushing geometries are used to increase travel distance differential and rate differential, then steering response and ride quality improve, but manufacturing cost increases and durability decreases

Engineering Contradiction:
Improvesteering responseVSAvoidbushing geometry complexity
Core Design Contradiction:
Ease of operationVSDevice complexity

Solution Approach 1:

The invention divides the single bushing assembly into two separate bushing assemblies (first and second bushings) with different geometries. Each bushing is optimized for its specific function: the first bushing provides vertical compliance while the second bushing provides longitudinal compliance. This segmentation allows each component to be simpler in geometry while achieving the combined effect of complex geometries, thereby improving steering response without increasing overall complexity or reducing durability.

Inventive Principle:
Principle #1Segmentation

2Ease of operation

If complex bushing geometries are used to increase travel distance differential and rate differential, then ride quality improves, but manufacturing cost increases

Engineering Contradiction:
Improveride qualityVSAvoidmanufacturing cost
Core Design Contradiction:
Ease of operationVSEase of manufacture

Solution Approach 1:

By segmenting the compliance function into two separate bushings, each with simpler geometry, the manufacturing cost is reduced. The first bushing handles vertical ride quality while the second bushing handles longitudinal movement. This approach achieves the same ride quality improvement as complex geometries but with simpler, more cost-effective manufacturing.

Inventive Principle:
Principle #1Segmentation

3Device complexity

If a single bushing assembly is used to pivotally couple the longitudinal arm, then the structure is simple and cost-effective, but the travel distance and rate differential are limited

Engineering Contradiction:
Improvestructural simplicityVSAvoidtravel distance differential
Core Design Contradiction:
Device complexityVSLength of moving object

Solution Approach 1:

The invention maintains structural simplicity by using only two bushing assemblies instead of one complex bushing, while achieving greater travel distance differential. The first bushing allows vertical movement and the second bushing allows longitudinal movement, creating independent compliance paths that increase the overall travel distance differential without significantly increasing structural complexity.

Inventive Principle:
Principle #1Segmentation

4Device complexity

If a single bushing assembly is used to pivotally couple the longitudinal arm, then the structure is simple and cost-effective, but the travel rate differential is limited

Engineering Contradiction:
Improvestructural simplicityVSAvoidtravel rate differential
Core Design Contradiction:
Device complexityVSSpeed

Solution Approach 1:

By separating the compliance functions into two distinct bushings, each optimized for different movement rates, the invention achieves greater travel rate differential. The first bushing is optimized for vertical movement rate while the second bushing is optimized for longitudinal movement rate, allowing each to operate at its optimal rate without compromise.

Inventive Principle:
Principle #1Segmentation

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 provides improved steering response, reduced ride harshness, and increased shock absorber efficiency by decoupling travel distance and spring rate along different axes, while maintaining cost-effectiveness and durability.

Implementation Method 1

The bushing is made of a compliant material such that the longitudinal arm can move in the vertical and longitudinal directions relative to the hanger to a limited extent due to the compliance of the bushing

Methodology Applied
Scientific EffectCompliance: Elasticity

Implementation Method 2

different bushing spring rates in the vertical direction versus in the longitudinal direction

Methodology Applied
Scientific EffectSpring rate: Spring

Data Source

PatentEP3297860B1Link assembly for longitudinal arm vehicle suspension
Publication Date: 2020.07.15 FCA US LLC
  • EP3297860B1 patent drawingFigure 1
  • EP3297860B1 patent drawingFigure 2~3
  • EP3297860B1 patent drawingFigure 4~5

AI summary

A link assembly (42) for coupling a longitudinal arm (30A) to a mounting location of a vehicle (22) is provided. The link assembly (42) includes a link body (44), a first attachment member (46), a second attachment member (48), a first bushing assembly (70), and a second bushing assembly (72). The first attachment member (46) is disposed in the link body (44) and defines a first axis (50). The second attachment member (48) is disposed in the link body (44) and defines a second axis (58). The first bushing assembly (70) is disposed in the link body (44) and supports the first attachment member (46) in the link body (44). The second bushing assembly (72) is disposed in the link body (44) and supports the second attachment member (48) in the link body (44). The first axis (50) of the first attachment member (46) is spaced from the second axis (58) of the second attachment member (48) by an off-set distance and the first axis (50) and second axis (58) extend in different, non-parallel directions.