Non-woven Filter Medium with High Modulus Fibers for Low Elongation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing filtering media struggle with high air rate filtration due to high pressure drops, elongation, and choking, especially in thin-type filter units designed for high air flow, which limits their effectiveness and lifespan in applications like automobile air conditioning.
Innovation Solution
A non-woven filtering medium constructed with organic fibers having varying Young's moduli and fineness, where non-crimped fibers with high Young's modulus and specific strength are used, along with a resin with a glass transition temperature of 30°C or more, to create a fabric with high air permeability and low elongation, preventing structure pressure drops and allowing for large air flow processing.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If a thin filtering medium is used to reduce structure pressure drop, then the filter can process large air flow, but the material itself causes high ventilation resistance and easy elongation
Solution Approach 1:
The filtering medium uses a composite structure combining a net-like support (providing dimensional stability and bending resistance) with a filtering layer (providing filtration function). This composite material approach allows the thin filter to maintain structural integrity while processing large air flows, resolving the contradiction between thinness and stability.
2Productivity
If the crest height is increased to reduce structure pressure drop, then large air flow can be processed, but disturbance in crest pitch interval occurs due to interference with net lattice interval
Solution Approach 1:
The invention applies different structural characteristics to different regions: the net-like support provides structural stability while the filtering layer contains the pleats. By locally optimizing each component's function, the filter achieves both large air flow processing and uniform crest pitch intervals without interference.
3Device complexity
If a net-like support is used, then the filter structure is simple, but dust retention is low causing large pressure drop increase and short lifespan
Solution Approach 1:
The filter combines a net-like support structure with a filtering layer that has high dust retention capability. The composite structure maintains simplicity while the filtering layer prevents dust penetration, reducing pressure drop increase and extending filter lifespan.
4Reliability
If glass fiber is used in the filtering medium, then filtration performance is improved, but glass fiber cracks during pleats processing and flies, causing maintenance and hygiene problems
Solution Approach 1:
The invention changes the material parameter from glass fiber to organic fiber, which has comparable filtration performance but superior flexibility and resistance to cracking during pleats processing. This parameter change eliminates fiber flying issues while maintaining filtration effectiveness.
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 results in a filtering medium with high specific strength, low elongation, and high air permeability, enabling efficient high air rate filtration with reduced pressure drops and noise, while maintaining dust capturing efficiency and extending the filter's lifespan.
Implementation Method 1
single fibers are fixed with a resin having a glass transition temperature of 30°C or more
Implementation Method 2
a non-crimped single fiber having a Young's modulus of 150 cN/dtex or more, and a fineness of 7 dtex or more is contained at a ratio of 20% or more of a total fiber mass
Data Source
AI summary
To provide a filtering medium which is not be elongated by air pressure even though it is thin and to provide a filter unit being able to treat high volume of air, a filtering medium is comprised of a non-woven fabric containing mainly an organic fiber, in which single fibers are fixed, wherein the non-woven fabric is constructed of a plurality of single fibers having different Young's moduli and finenesses, a non-crimped single fiber having a Young's modulus of 150 cN/dtex or more, and a fineness of 7 dtex or more is contained at a ratio of 20% or more of a total fiber mass, and single fibers are fixed with a resin having a glass transition temperature of 30°C or more.