Muffler Partition Wall Suppresses Whistling Noise

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional mufflers for internal combustion engines in vehicles suffer from abnormal noise issues like whistling sounds due to pressure fluctuations between the tail pipe and tail cover, which are difficult to suppress without compromising design aesthetics or making exhaust gas sampling inspections cumbersome.

Innovation Solution

A muffler design featuring a partition wall that compartmentalizes the space between the tail pipe and tail cover into multiple sections, reducing the volume affected by pressure fluctuations and incorporating a pipe-shaped partition wall for easier manufacturing and noise suppression, along with a fold portion to prevent air from being directly affected by pressure.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Object-affected harmful factors

If the tail pipe is extended more rear than the tail cover, then abnormal noise is suppressed, but the rear end portion of the tail pipe is exposed from the tail cover, unsatisfying design requirements

Engineering Contradiction:
Improveabnormal noiseVSAvoidmuffler design
Core Design Contradiction:
Object-affected harmful factorsVSShape

Solution Approach 1:

The space between the tail pipe and tail cover is segmented into multiple independent spaces by partition walls. This segmentation reduces the volume of each individual space, thereby suppressing abnormal noise while allowing the tail pipe to remain shorter than the tail cover for better design appearance.

Inventive Principle:
Principle #1Segmentation

2Object-affected harmful factors

If the gap between the tail cover and tail pipe is narrowed to prevent abnormal noise, then noise suppression is improved, but it becomes difficult to insert a tube for exhaust gas sampling inspection

Engineering Contradiction:
Improveabnormal noiseVSAvoidexhaust gas sampling inspection
Core Design Contradiction:
Object-affected harmful factorsVSEase of operation

Solution Approach 1:

The gap space is divided into multiple smaller spaces by partition walls. This segmentation reduces the volume of air affected by pressure fluctuations, suppressing abnormal noise while maintaining sufficient gap width for tube insertion during exhaust gas sampling inspection.

Inventive Principle:
Principle #1Segmentation

3Shape

If the tail pipe rear edge is positioned more front than the tail cover rear edge, then design is improved by preventing exposure, but pressure fluctuation becomes larger

Engineering Contradiction:
Improvemuffler designVSAvoidpressure fluctuation
Core Design Contradiction:
ShapeVSStress or pressure

Solution Approach 1:

By dividing the space into multiple smaller spaces using partition walls, the volume of air subjected to pressure fluctuation is reduced. This allows the tail pipe to be positioned more front for better design while the segmented structure mitigates the impact of pressure fluctuations.

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

Effectively suppresses abnormal noise occurrences while allowing for smooth exhaust gas sampling inspections and improving muffler design by reducing pressure fluctuation impact, simplifying manufacturing, and enhancing noise reduction without exposing the tail pipe.

Implementation Method 1

a partition wall (24) disposed in a space (23) formed between the tail pipe (21) and the tail cover (22)... making a volume of a space affected by pressure fluctuation at an exhaust time smaller... suppress an occurrence of an abnormal noise such as a whistling sound

Methodology Applied
Scientific EffectAcoustic absorption: Acoustic Absorption

Data Source

PatentEP2514938B8Muffler of internal combustion engine
Publication Date: 2015.09.16 SUZUKI MOTOR CORP

AI summary

A muffler (16) of an internal combustion engine is characterized in having a muffler main body (18) connected to a rear end of an exhaust pipe of the internal combustion engine, a tail pipe (21) extended from a rear end surface (20)of the muffler main body, and a tail cover (22) covering an outer periphery of the tail pipe, the muffler comprises a partition wall (24) compartmentalizing a space (23) formed between the tail pipe and the tail cover into at least two or more spaces (34, 35).