Exhaust Isolator Support Arm Layout for Flexion-Free Load Transfer

Solution Overview

Problem

Existing automotive exhaust system isolators face durability issues due to the concentration of loads around bending points when subjected to flexion, which can weaken the support arms and reduce their effectiveness in withstanding vibrations and swinging loads.

Innovation Solution

The isolator features an elastomeric body with a central member and peripheral member connected by C-shaped and inverted C-shaped support arms, which operate under traction/compression loads instead of flexion, distributing loads along the support arms and increasing durability, and includes buffer holes for temperature dissipation and deformation.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Strength

If support arms are designed to connect central member and peripheral member, then the isolator can withstand static and dynamic loads, but the support arms are subjected to flexion loads causing load concentration around bending points which weakens the support arms and reduces durability

Engineering Contradiction:

Improvestrength of support armsVSAvoiddurability of isolator

Core Design Contradiction:

StrengthVSReliability

Solution Approach 1:

The patent inverts the loading mode of the support arms from flexion to traction/compression. Instead of allowing the support arms to bend and concentrate loads at bending points, the design configures them to work primarily in axial tension and compression directions, distributing loads along their entire length and eliminating stress concentration at bending points, thereby significantly improving durability

Inventive Principle:

Principle #13The other way round (Inversion)

Solution Approach 2:

The patent changes the operational parameters of the support arms by modifying their geometric configuration and connection points. The support arms are designed with specific shapes (C-shaped, inverted C-shaped, L-shaped, or Z-shaped) and connection arrangements that transform the loading conditions from flexion-dominated to traction/compression-dominated, optimizing their mechanical performance

Inventive Principle:

Principle #35Parameter changes

2Adaptability or versatility

If the central member moves up and down to accommodate terrain variations, then the isolator adapts to different driving conditions, but the support arms subjected to flexion loads experience increased stress and reduced service life

Engineering Contradiction:

Improveadaptability to terrainVSAvoidservice life of support arms

Core Design Contradiction:

Adaptability or versatilityVSDuration of action of stationary object

Solution Approach 1:

The patent inverts the loading mode of the support arms from flexion to traction/compression. Instead of allowing the support arms to bend and concentrate loads at bending points, the design configures them to work primarily in axial tension and compression directions, distributing loads along their entire length and eliminating stress concentration at bending points, thereby significantly improving durability

Inventive Principle:

Principle #13The other way round (Inversion)

Solution Approach 2:

The patent changes the operational parameters of the support arms by modifying their geometric configuration and connection points. The support arms are designed with specific shapes (C-shaped, inverted C-shaped, L-shaped, or Z-shaped) and connection arrangements that transform the loading conditions from flexion-dominated to traction/compression-dominated, optimizing their mechanical performance

Inventive Principle:

Principle #35Parameter changes

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

This design enhances the isolator's durability by distributing loads effectively and preventing excessive deformation, thereby improving its ability to handle vertical loads and vibrations, while also dissipating heat and maintaining structural integrity.

Implementation Method 1

an elastomeric body having a central member with a through hole for inserting a pin of an exhaust system, and a peripheral member surrounding the central member and connected to said central member through four support arms

Methodology Applied

Scientific EffectElasticity: Elasticity

Implementation Method 2

The isolator also comprises four buffer holes formed between the peripheral member and the support arms, and between the central member and the support arms

Methodology Applied

Scientific EffectConvection: Convection

Data Source

PatentEP3939818B1Automotive exhaust system isolator

Publication Date: 2024.02.21 CIKAUTXO

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AI summary

An automotive exhaust system isolator (1) comprising an elastomeric body (2) comprising a central member (3) having a through hole (3.1) for inserting a pin of an exhaust system, and a peripheral member (4), being configured to be coupled to a vehicle body, which surrounds the central member (3) and is connected to said central member (3). The elastomeric body (2) further comprises two support arms (5) having a first end and a second end , the first and second ends of the respective support arms (5) being joined to the peripheral member (4), and the central member (3) being connected to the two support arms (5) by means of respective lateral bridges (6), so that, in use, the first ends of the support arms (5) are positioned in an upper part of the peripheral member (4) and the second ends are positioned in a lower part of the peripheral member (4), the central member (3) being positioned between both support arms (5).