Rubber Compound Speaker Diaphragm for Vibration and Temperature Resistance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing loudspeaker diaphragms made of high modulus plastic film and thermoplastic polyurethane elastomer suffer from mechanical weakness, poor heat and cold resistance, and brittleness, leading to film rupture and reduced service life.
Innovation Solution
A diaphragm composed of an elastomer layer made of a rubber compound containing nitrile rubber and hydrogenated nitrile rubber with acrylonitrile blocks, along with fillers like carbon black, and a controlled vulcanizing agent, enhancing mechanical strength, cold resistance, and damping performance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If high modulus plastic film is used in the diaphragm, then mechanical strength is improved, but the film is difficult to withstand large mechanical vibration in high frequency circumstance, leading to film rupture
Solution Approach 1:
The patent uses a composite structure consisting of a plastic film layer and a rubber layer. The plastic film layer provides mechanical strength, while the rubber layer provides flexibility and resistance to mechanical vibration. This composite material approach resolves the contradiction by combining materials with complementary properties, allowing the diaphragm to withstand high frequency vibrations without film rupture.
2Ease of operation
If thermoplastic polyurethane elastomer is used in the diaphragm, then flexibility is improved, but the material has poor heat and cold resistance, causing plastic deformation at high temperature and brittleness at low temperature
Solution Approach 1:
The patent combines thermoplastic polyurethane elastomer with rubber material in a composite structure. The thermoplastic layer provides flexibility and elastic recovery, while the rubber layer provides resistance to extreme temperatures. This composite approach allows the diaphragm to maintain flexibility across a wide temperature range without plastic deformation or brittleness.
3Adaptability or versatility
If a composite structure of multiple materials is used in the diaphragm, then various properties are attempted to be improved, but the comprehensive performance is poor due to material incompatibility and performance trade-offs
Solution Approach 1:
The patent employs a carefully designed composite structure where a plastic film layer is combined with a rubber layer in specific configurations. The materials are selected and arranged to ensure compatibility and synergistic performance. The plastic film provides strength and dimensional stability, while the rubber layer provides flexibility, damping, and temperature resistance, achieving consistent comprehensive performance.
4Temperature
If the diaphragm material needs to withstand extreme temperatures, then heat resistance is improved, but the material becomes more rigid and less resilient
Solution Approach 1:
The patent uses a composite structure where the rubber layer is specifically designed to maintain resilience at extreme temperatures. The rubber material provides thermal stability while maintaining elastic properties, preventing the diaphragm from becoming overly rigid. The composite structure allows heat resistance and resilience to coexist by distributing functional requirements across different material layers.
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 diaphragm exhibits improved mechanical strength, resilience, and damping properties, allowing operation under extreme temperatures and reducing the risk of film rupture, with a longer service life and maintained acoustic performance.
Implementation Method 1
The elastomer layer is made of a rubber compound. The rubber compound comprises nitrile rubber and hydrogenated nitrile rubber, and both the nitrile rubber and the hydrogenated nitrile rubber contain acrylonitrile blocks
Implementation Method 2
the rubber compound further comprises a vulcanizing agent. In terms of mass percentage, the content of the vulcanizing agent in the rubber compound is 0.5% to 5%
Implementation Method 3
the diaphragm has a damping factor in the range of greater than 0.15
Implementation Method 4
the rubber compound further comprises filler. In terms of mass percentage, the content of the filler in the rubber compound is 5% to 60%
Data Source
Figure 1~2
Figure 3
AI summary
A diaphragm and a sound generating apparatus. The diaphragm comprises at least one elastomer layer, and the elastomer layer is made of a rubber compound. The rubber compound comprises nitrile rubber and hydrogenated nitrile rubber. Both the nitrile rubber and the hydrogenated nitrile rubber contain acrylonitrile blocks. In terms of mass percentage, the range of the content of acrylonitrile blocks is 20% to 80%. The described diaphragm has excellent mechanical strength, cold resistance, and resilience, and has high damping performance.