Liquid-Resistant Acoustic Port Module Using PTFE Membrane
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Electronic devices with electro-acoustic transducers face damage from liquid intrusion, particularly when used in wet environments, as existing solutions fail to effectively prevent water ingress while maintaining acoustic transparency.
Innovation Solution
The development of liquid-resistant port modules and microphone assemblies that incorporate a gas-permeable, acoustically transparent membrane and a protective barrier to prevent liquid intrusion, allowing for pre-assembly testing and increased yield, and utilizing materials like PTFE and ePTFE for enhanced hydrophobicity and durability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a liquid-resistant membrane is used to prevent water ingress, then liquid resistance is improved, but acoustic transparency deteriorates
Solution Approach 1:
The patent employs a porous PTFE membrane as the liquid-resistant port membrane. The porous structure allows acoustic energy to pass through while the hydrophobic properties of PTFE prevent liquid penetration. The membrane's pore size and distribution are optimized to maintain acoustic transparency while providing effective liquid resistance.
Solution Approach 2:
The patent uses composite construction combining PTFE membrane with supporting structures including a cap, housing, and adhesive layers. This composite approach creates a multi-functional assembly that provides both liquid resistance and acoustic transparency, with each layer contributing specific properties to the overall system performance.
2Reliability
If liquid-resistant sealing structures are added to electronic devices, then liquid resistance is improved, but device complexity increases
Solution Approach 1:
The patent divides the liquid-resistant structure into separate modular components: a port module with the PTFE membrane, a cap, a housing with acoustic channel, and adhesive layers. This segmentation allows each component to be optimized independently and facilitates assembly while maintaining overall liquid resistance without excessive complexity.
Solution Approach 2:
The port module design integrates multiple functions into a single assembly: the PTFE membrane provides both liquid resistance and acoustic transparency, the acoustic channel directs sound waves, and the adhesive structures provide both bonding and sealing functions. This multi-functionality reduces the number of separate components needed.
3Reliability
If liquid-resistant membranes are integrated into final assembly, then liquid resistance is improved, but manufacturing yield decreases due to inability to pre-test
Solution Approach 1:
The patent enables preliminary liquid-resistance testing of the port module assembly before final integration into the electronic device. The modular design allows the PTFE membrane, cap, and housing to be assembled and tested independently, identifying defects early in the manufacturing process and improving overall yield by preventing defective units from reaching final assembly.
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 inhibits liquid intrusion while allowing acoustic energy to pass through, ensuring the reliability and performance of electronic devices in wet conditions, with increased manufacturing efficiency through pre-assembly testing and the use of hydrophobic materials.
Implementation Method 1
Port modules have a cap defining a gas-permeable region and spanning the aperture corresponding to the first end of the housing. The gas-permeable region of the cap defines an acoustic pathway through the cap.
Implementation Method 2
The port membrane can prevent movement of water across the port membrane for hydrostatic pressure gradients across the port membrane below a selected threshold hydrostatic pressure gradient. The port membrane can be formed of one or more of PTFE and ePTFE.
Implementation Method 3
The housing defines an acoustic channel. The housing extends from a first end to an opposed second end. Each end has a corresponding aperture open to the channel.
Implementation Method 4
An adhesive can be positioned between the cap and the abutment and can affix the cap to the abutment. The second adhesive can affix the gas-permeable membrane to the cap.
Data Source
AI summary
A liquid-resistant module can be formed as a laminated construct having a housing, a cap, and a port membrane to inhibit liquid from passing across the membrane. The housing defines an internal duct extending from an inlet port to an outlet region. The cap defines an acoustic port and extends across the outlet region of the housing. The port membrane is attached to the cap and extends across the acoustic passage. The port membrane inhibits passage of liquid water through the membrane at differential pressures across the membrane less than a threshold pressure differential, and yet is gas permeable. The module can provide a liquid-resistant seal with an enclosure of an electronic device, and an enclosed microphone transducer or an enclosed loudspeaker transducer can be attached to the cap such that a port opening to or from the transducer is aligned with the acoustic port.