Automotive Dash Insulator Resonance Suppression
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional soundproof materials for motor vehicles, such as dash insulators, suffer from reduced soundproofing effectiveness due to resonance phenomena between felt layers and intermediate sheet layers, particularly in the low frequency range, leading to increased noise transmission.
Innovation Solution
A laminated soundproof body comprising a sound absorption layer of the membrane-vibration type and a perforated sound insulation layer, with the sound absorption layer acting as a non-air permeable or air permeable thin membrane layer, and the perforated sound insulation layer having a predetermined opening ratio and number of openings to maintain a phase difference that suppresses resonance between the two layers, effectively absorbing and insulating noise across a wide frequency range.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If felt layers and intermediate sheet layers are used in conventional soundproof materials, then the material structure is simple and easy to manufacture, but resonance phenomena occur in the low frequency range which reduces soundproofing effectiveness
Solution Approach 1:
The patent applies composite materials by combining a membrane-vibration type sound absorption layer (made of flexible materials like rubber or resin) with a perforated sound insulation layer. This composite structure eliminates the resonance problems of conventional felt layers while maintaining ease of manufacture through integrated layering.
Solution Approach 2:
The patent changes the physical parameters of the soundproofing material by using a membrane-vibration type layer with specific flexibility and damping characteristics, rather than conventional felt. The perforated layer also has controlled opening ratios and hole distributions to suppress resonance in the low frequency range.
2Ease of operation
If air-permeable felt layers are used, then the material allows air flow and is easy to process, but resonance phenomena are induced which increase noise transmission
Solution Approach 1:
The patent replaces air-permeable felt layers with a membrane-vibration type sound absorption layer made of flexible materials. This thin film structure provides better noise transmission control through controlled vibration and damping, while still allowing for easy processing and installation.
Solution Approach 2:
The patent converts the potential harm of resonance phenomena into benefit by designing the membrane-vibration type layer to specifically target and suppress low frequency resonance. The flexible material's natural vibration characteristics are harnessed to absorb noise rather than amplify it.
3Device complexity
If conventional felt layers are used for soundproofing, then the material is simple in construction, but transmission sound loss is reduced due to resonance between layers
Solution Approach 1:
The patent uses a composite material structure with a membrane-vibration type sound absorption layer combined with a perforated sound insulation layer. This composite design reduces transmission sound loss by preventing resonance between layers, while keeping the overall construction relatively simple through integrated layering.
Solution Approach 2:
The patent applies mechanical vibration principles by using a membrane-vibration type layer that vibrates in response to incident sound waves. This vibration absorbs acoustic energy and converts it to mechanical energy, reducing transmission sound loss without requiring complex multi-layer constructions.
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 configuration significantly enhances soundproofing by absorbing low-frequency noise components through membrane vibration and insulating high-frequency components, improving soundproofing effects over a broader frequency range while maintaining a lightweight structure.
Implementation Method 1
a sound absorption layer of a membrane-vibration type (50) which is formed from a non-air permeable thin membrane layer or an air permeable thin membrane layer made of a flexible material
Implementation Method 2
the noise are partially absorbed by the one side layer due to the porous material which is the forming material of the one side layer
Implementation Method 3
maintain vibrations of the laminated body within a range of a phase difference which can suppress a resonance phenomenon between each of vibrations of the sound absorption layer of the membrane-vibration type and the perforated sound insulation layer
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A dash insulator (DS) is constructed by layering a front layer (40), a sound absorption layer (50) of a membrane-vibration type and a perforated sound insulation layer (60). A layered body of the sound absorption layer and the perforated sound insulation layer is constructed such that the inner diameter and the opening ratio of opening portions of the perforated sound insulation layer are set to enable suppression of a resonance phenomenon between vibrations of the sound absorption layer and the perforated sound insulation layer in relation to low frequency range noise components of noise.