Speaker Diaphragm Using Thermoplastic Polyester Elastomer Film
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing speaker diaphragms, particularly those made from silicone rubber, suffer from low elastic modulus and hardness, leading to reduced sensitivity and sound quality due to increased thickness and weight, along with poor elastic recovery and susceptibility to plastic deformation during vibration.
Innovation Solution
A speaker diaphragm comprising two surface layers and at least one intermediate layer, where one surface layer is a thermoplastic polyester elastomer film with a Young's modulus of 1-1000 MPa and an elastic recovery rate of ≥80% after 10% strain, and an adhesive layer with a loss factor ≥0.1, providing improved stiffness, damping, and resilience.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If silicone rubber is used to make the diaphragm thicker to ensure strength, then the strength is improved, but the weight increases and space allowance for vibration is reduced
Solution Approach 1:
The patent uses a composite structure consisting of a thermoplastic polyester elastomer film layer (providing strength and stiffness) and an adhesive layer (providing damping). This composite structure achieves the required diaphragm strength with a thinner overall thickness, thereby reducing the vibration system weight while maintaining structural integrity.
Solution Approach 2:
The patent changes the material parameters by selecting a thermoplastic polyester elastomer with specific Young's modulus (1-1000 MPa) and loss factor (≥0.015) values. This parameter optimization allows the diaphragm to achieve sufficient strength at reduced thickness, solving the weight-strength trade-off.
2Strength
If silicone rubber is used to make the diaphragm thicker to ensure strength, then the strength is improved, but the space allowance for vibration is reduced
Solution Approach 1:
The composite structure of thermoplastic polyester elastomer film and adhesive layer provides high strength-to-thickness ratio. The thermoplastic polyester elastomer film layer contributes primarily to strength while the adhesive layer provides damping, enabling a thinner overall diaphragm structure that preserves vibration space.
Solution Approach 2:
By optimizing the Young's modulus and thickness parameters of the thermoplastic polyester elastomer film layer, the patent achieves sufficient strength with reduced thickness, thereby maintaining adequate space allowance for vibration movement.
3Weight of moving object
If the diaphragm is made thinner to reduce weight, then sensitivity is improved, but the strength is reduced
Solution Approach 1:
The composite structure compensates for the reduced thickness by using high-strength thermoplastic polyester elastomer material. The adhesive layer bonded between the film layers provides additional structural support and damping, maintaining overall strength despite the thinner design.
4Stability of the object's composition
If silicone rubber is used, then elasticity is improved, but the elastic recovery rate is low and plastic deformation occurs
Solution Approach 1:
The patent changes the material selection from silicone rubber to thermoplastic polyester elastomer, which has superior elastic recovery properties. The material parameters (Young's modulus of 1-1000 MPa and loss factor of ≥0.015) are optimized to achieve both elasticity and high elastic recovery rate (≥80% after 10% strain), preventing plastic deformation during vibration.
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 speaker diaphragm with enhanced stiffness, damping, and thermal plasticity, allowing for a thinner design that reduces weight and improves sensitivity, while maintaining excellent resilience and sound quality, with a wider elastic region and lower resonant frequency.
Implementation Method 1
an elastic recovery rate after 10% strain being greater than or equal to 80%
Implementation Method 2
a loss factor being greater than or equal to 0.015
Implementation Method 3
at least one of the intermediate layers is an adhesive layer, wherein the thermoplastic polyester elastomer film layer has a Young's module of 1-1000 MPa, a loss factor being greater than or equal to 0.015
Data Source
AI summary
The present disclosure provides a speaker diaphragm and a speaker. The diaphragm includes two surface layers compounded together and at least one intermediate layer located between the two surface layers, at least one of the surface layers is a thermoplastic polyester elastomer film layer, and at least one of the intermediate layers is an adhesive layer, wherein the thermoplastic polyester elastomer film layer has a Young's module of 1-1000 MPa, a loss factor being greater than or equal to 0.015, and an elastic recovery rate after 10% strain being greater than or equal to 80%. The speaker diaphragm may be made very thin, thus reducing the weight of the speaker diaphragm, improving the space allowance for vibration, improving the sensitivity, and making the F0 of the speaker lower. Further, elastic area of the speaker diaphragm is wider and the resilience performance is excellent.