Acoustic Path Pressure Vent for Speaker Modules
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Speakers and microphones may malfunction due to hindered movement of the acoustic membrane caused by liquid ingress or significant differences in barometric pressure, leading to distorted sound output.
Innovation Solution
Incorporating a pressure vent in the acoustic path of the speaker or microphone module, which can be acoustically opaque and made of materials like PTFE or sintered metal discs, to equalize barometric pressure on both sides of the acoustic membrane, preventing deformation and ensuring operation, and including a cavity with a hydrophobic coating to manage liquid presence.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the speaker or microphone module is made waterproof to prevent liquid ingress, then water resistance is improved, but barometric pressure equalization is hindered
Solution Approach 1:
The patent employs a hydrophobic porous coating applied to the acoustic membrane that allows air molecules to pass through while blocking liquid water. The porous structure creates capillary pressure that repels water based on surface tension effects, yet permits barometric pressure equalization through the same membrane. This resolves the contradiction by making the membrane selectively permeable to gases while maintaining waterproofing.
Solution Approach 2:
The acoustic membrane is constructed as a composite structure combining a base membrane material with a hydrophobic porous coating layer. This composite approach integrates the waterproofing function of the hydrophobic coating with the acoustic transmission function of the base membrane, while simultaneously enabling pressure equalization through the porous structure.
2Strength
If the acoustic membrane is made rigid to improve structural strength, then strength is improved, but movement freedom is reduced
Solution Approach 1:
The patent utilizes a thin-film acoustic membrane that is sufficiently flexible to vibrate freely for acoustic operation while being reinforced with a hydrophobic porous coating that provides structural support. The thin-film nature allows adequate movement freedom while the coating adds necessary strength and waterproofing properties.
Solution Approach 2:
The membrane operates as a composite structure where the base material provides flexibility and acoustic responsiveness, while the hydrophobic porous coating layer provides structural reinforcement and waterproofing. This composite construction allows the membrane to maintain both strength and movement freedom simultaneously.
3Productivity
If the pressure vent is made acoustically transparent to allow sound passage, then acoustic performance is improved, but pressure equalization efficiency is reduced
Solution Approach 1:
The hydrophobic porous coating acts as the pressure vent mechanism, where the porous structure provides sufficient open area for efficient barometric pressure equalization while the hydrophobic properties prevent liquid ingress. The porous nature allows acoustic signals to pass through with minimal attenuation, maintaining acoustic performance while ensuring reliable pressure equalization.
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 pressure vent ensures uninterrupted operation by equalizing pressures and preventing membrane deformation, while the hydrophobic coating aids in liquid removal, maintaining sound quality and water resistance.
Implementation Method 1
The membrane may allow air to pass but may prevent the passage of water and/or water vapor
Implementation Method 2
One or more portions of such a cavity may be coated (such as via vapor deposition) with a hydrophobic coating
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A speaker or microphone module includes an acoustic membrane and at least one pressure vent. The pressure vent equalizes barometric pressure on a first side of the acoustic membrane with barometric pressure on a second side of the acoustic membrane. Further, the pressure vent is located in an acoustic path of the speaker or microphone module. In this way, differences between barometric pressures on the different sides of the acoustic membrane may not hinder movement of the acoustic membrane. In one or more implementations, the pressure vent may be acoustically opaque. As the pressure vent is located in the acoustic path of the speaker or microphone module, being acoustically opaque may ensure that the pressure vent itself does not interfere with the operation of the speaker or microphone module.