Vibration-Isolated Exhaust Treatment Bracket for Short Pipe Stress

Solution Overview

Problem

The short length and weight of diesel oxidation catalyst (DOC) exhaust pipes in transport refrigeration systems pose a risk of failure due to stress concentrations, necessitating a robust mounting solution that also accounts for vibration isolation.

Innovation Solution

A mounting assembly comprising a first and second mounting bracket connected by vibration isolators, with the second bracket offset from the first, providing a stable and vibration-isolated configuration for the exhaust treatment unit within the transport refrigeration system.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Volume of moving object

If the exhaust pipe is made short to meet housing sizing constraints, then the housing size is reduced, but the risk of pipe failure increases due to stress concentrations

Engineering Contradiction:

Core Design Contradiction:

Volume of moving objectVSReliability

Solution Approach 1:

The patent introduces a mounting bracket as an intermediary component between the exhaust pipe and the housing. This bracket distributes the mechanical loads and stress concentrations away from the short exhaust pipe, thereby maintaining pipe reliability while allowing the housing to remain compact in size.

Inventive Principle:

Principle #24Intermediary (Mediator)

Solution Approach 2:

The mounting system is segmented into multiple components: the exhaust pipe, the mounting bracket with stress distribution features, and the housing. This segmentation allows the stress management function to be separated from the exhaust pipe itself, enabling the pipe to be short without compromising reliability.

Inventive Principle:

Principle #1Segmentation

2Volume of moving object

If the exhaust pipe is made short to meet housing sizing constraints, then the housing size is reduced, but stress concentrations increase

Engineering Contradiction:

Core Design Contradiction:

Volume of moving objectVSStress or pressure

Solution Approach 1:

The mounting bracket serves as a mediator that intercepts and redistributes the stress concentrations. By positioning the bracket between the pipe and housing, it prevents stress concentration from developing in the short exhaust pipe while maintaining compact housing dimensions.

Inventive Principle:

Principle #24Intermediary (Mediator)

Solution Approach 2:

The mounting bracket incorporates local stress distribution features such as increased thickness or reinforcement at critical locations. This local quality enhancement allows the bracket to handle stress concentrations without requiring the entire housing to be larger.

Inventive Principle:

Principle #3Local quality

3Device complexity

If rigid mounting is used to secure the exhaust treatment unit, then the mounting is simple, but vibrations are transmitted causing potential failure

Engineering Contradiction:

Core Design Contradiction:

Device complexityVSReliability

Solution Approach 1:

The mounting bracket acts as a vibration-isolating intermediary between the exhaust treatment unit and the housing. It provides the necessary mechanical support while dampening vibrations, thus maintaining reliability without significantly increasing mounting system complexity.

Inventive Principle:

Principle #24Intermediary (Mediator)

Solution Approach 2:

The mounting bracket is designed with inherent vibration-damping characteristics that cushion against vibrations before they can be transmitted to the exhaust treatment unit. This beforehand cushioning protects the unit from vibration-induced failures while keeping the mounting system relatively simple.

Inventive Principle:

Principle #11Beforehand cushioning (Prior cushioning)

4Reliability

If vibration isolation is implemented, then the reliability is improved, but the mounting system complexity increases

Engineering Contradiction:

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The vibration isolation function is merged into the mounting bracket itself rather than being a separate system. The bracket combines structural support and vibration damping in a single integrated component, improving reliability while minimizing increases in overall system complexity.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The mounting bracket performs multiple functions simultaneously: it provides mechanical support, distributes stress concentrations, and isolates vibrations. This multi-functionality achieves improved reliability without proportionally increasing system complexity, as one component accomplishes multiple protective tasks.

Inventive Principle:

Principle #6Universality (Multi-functionality)

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 effectively reduces the risk of exhaust pipe failure by distributing stress and isolating vibrations, ensuring reliable operation of the transport refrigeration system while meeting emission regulations.

Implementation Method 1

The central portion and the base are connected by the at least one vibration isolator

Methodology Applied

Scientific EffectVibration isolation: Damping

Data Source

PatentEP4245586A1Vibration isolating bracket for exhaust treatment unit

Publication Date: 2023.09.20

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AI summary

A mounting assembly (60) for at least one component of a transport refrigeration unit (12) includes a first mounting bracket (62) including a body having a central portion (68), and a second mounting bracket (64) including a base (84). The base (84) is offset from a surface of the central portion (68). The mounting assembly (60) additionally includes at least one vibration isolator (98). The central portion (68) and the base (84) are connected by the at least one vibration isolator (98).