扬声器纸质振膜材料复弹性模量测试系统研究

Testing System of Complex Elastic Modulus of Paper Diaphragm for Loudspeaker

采用完全非接触式的声激振、激光拾振方式,并采用了正弦扫频激振法,建立了扬声器纸质振膜材料试样的复数弹性模量测试系统及专用的振动台和采集分析软件。建立了考虑黏性力作用下试样的悬臂梁动力学模型,提高了纸样动态弹性模量和损耗因数的计算精度。经实验验证该套系统具有较高的精度、重复性和可靠性,可以为扬声器生产企业选择纸盆提供依据,也可以为新型纸质振膜材料的开发提供理论指导。

A system for complex elastic modulus measurement of loudspeaker paper diaphragm material based on acoustical excitation was designed in this paper. Vibration signal of the paper was detected by a laser transducer in a no-touching way. Meanwhile sine sweeping excita- tion method was used for testing. A set of vibration apparatus and the detection and analysis software were developed. The cantilever dynami- cal model considering the viscoelasticity of paper material was built, making the results of dynamic elastic modulus and damping factor more accurate. Experiments illustrated that the system has high accuracy, repeatability and reliability, and it can help enterprise to choose the cone paper, and to develop new type paper diaphragm materials.