Porous Plate Soundproofing Structure for Broadband Noise
Solution Overview
Problem
Existing soundproofing structures face challenges in achieving high soundproofing performance across a broad frequency band, particularly in miniaturizing designs while ensuring ventilation properties and light transmittance, and are inadequate for low-frequency sound absorption and clean room environments due to material limitations and resonance frequency limitations.
Innovation Solution
A soundproofing structure comprising a plate-like member with through-holes in the thickness direction and a frame member that enables membrane vibration, with an average opening diameter of through-holes ranging from 0.1 µm to 250 µm and a unique vibration frequency between 10 Hz to 100,000 Hz, allowing for efficient sound absorption across a broad frequency range without the need for a closed space.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If traditional sound absorbing materials (urethane sponge, glass wool) are used to increase sound absorption, then soundproofing performance is improved, but the volume of the material must be increased which is problematic when device size is limited
Solution Approach 1:
The patent uses a porous plate-like member with through-holes as the core soundproofing structure. The porous configuration allows sound waves to pass through and be absorbed while maintaining a compact form factor. The through-holes enable the plate to function as both a structural component and a sound absorption element, eliminating the need for bulky traditional soundproofing materials.
Solution Approach 2:
The patent changes the physical parameters of the plate-like member by creating through-holes with specific dimensions and patterns. This transforms the plate from a simple barrier into an acoustic resonance structure that absorbs sound energy. The parameter changes in hole size, distribution, and depth create resonant frequencies that target specific sound frequencies for absorption.
2Reliability
If membrane vibration soundproofing structure is used to absorb sound at resonance frequency, then sound absorption is increased at resonance frequency, but sound absorption is decreased at other frequencies making it difficult to widen the frequency band
Solution Approach 1:
The patent segments the sound absorption function across multiple plate-like members with different through-hole configurations. Each plate is tuned to absorb specific frequency ranges, and by stacking multiple plates with varying hole patterns, the system achieves broad frequency coverage. This segmentation allows each component to specialize in certain frequencies while the collective system covers the full spectrum.
Solution Approach 2:
The plate-like member serves multiple functions simultaneously: it acts as a structural barrier, a sound absorption resonator, and a ventilation passage. The through-holes enable both sound absorption through resonance and airflow for ventilation, making the structure multi-functional. This universality allows a single component to address multiple requirements that would traditionally need separate elements.
3Reliability
If Helmholtz resonance soundproofing structure with closed space is used, then sound absorption occurs at specific frequency, but the structure requires a closed space which increases device volume and complicates the structure
Solution Approach 1:
The patent extracts the essential sound absorption function from the complex Helmholtz resonance cavity structure and implements it in a simplified plate-like form. By using through-holes directly in the plate rather than requiring a enclosed cavity behind it, the design achieves similar acoustic effects with dramatically reduced complexity and volume. The plate itself becomes the resonating element rather than requiring a separate cavity system.
4Reliability
If fibrous sound absorbing materials are used, then sound absorption is achieved, but the environment is contaminated by fiber garbage and the material cannot be used in clean room environment or with precision equipment
Solution Approach 1:
The patent employs a porous plate-like member with through-holes as a non-fibrous alternative to traditional fibrous sound absorbing materials. This solid porous structure provides sound absorption through acoustic resonance while completely eliminating fiber shedding and contamination issues. The plate can be manufactured from various materials including metals, plastics, or ceramics that do not generate particulate contamination.
5Reliability
If urethane sponge or glass wool with three-dimensional pores is used, then sound absorption is achieved, but light transmittance is low which is problematic
Solution Approach 1:
The patent uses a porous plate-like member with through-holes that maintains light transmittance while providing sound absorption. The controlled porosity with through-holes allows light to pass through the plate while the holes create acoustic resonance for sound absorption. This differs from three-dimensional porous materials like foam that block light completely, as the through-hole configuration permits optical transmission.
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 high soundproofing performance across a broad frequency band, miniaturization, ensured ventilation, and light transmittance, effectively addressing the limitations of existing structures by enhancing sound absorption through membrane vibration and frictional heat generation in fine through-holes.
Implementation Method 1
membrane vibration of the plate-like member is enabled by fixing the plate-like member to a peripheral edge of an opening portion of the frame member
Implementation Method 2
sound absorption occurs at the resonance frequency of membrane vibration
Implementation Method 3
strong sound absorption occurs at a specific frequency due to the friction between the sounds and the through-holes during the reciprocation
Implementation Method 4
frictional heat generation in fine through-holes
Data Source
Figure 1~3
Figure 4~6B
Figure 6C~6E
AI summary
An object is to provide a soundproofing structure, a partition structure, a window member, and a cage which exhibit high soundproofing performance in a broad frequency band, can be miniaturized, can ensure ventilation properties, and have a light transmittance. Provided is a soundproofing structure including: a plate-like member which has a plurality of through-holes passing therethrough in a thickness direction; and a frame member which includes an opening portion, in which membrane vibration of the plate-like member is enabled by fixing the plate-like member to a peripheral edge of the opening portion of the frame member, an average opening diameter of the through-holes is in a range of 0.1 µm to 250 µm, and a first unique vibration frequency of the membrane vibration of the plate-like member is present in a range of 10 Hz to 100000 Hz.