Vibrating diaphragm and sound production device

Abstract

The invention discloses a vibrating diaphragm and a sound production device. Wherein the vibrating diaphragm is prepared from pouring type polyurethane, the pouring type polyurethane is prepared by vulcanizing a polyurethane prepolymer and a compounding agent, the polyurethane prepolymer is a block polymer, the block polymer is formed by alternately arranging hard segments and soft segments, the hard segments are isocyanate, the soft segments are polyol flexible long chains, and the flexible long chains are made of polyurethane. The end groups of the block polymer are isocyanate hard segments, and the elastic recovery rate of the vibrating diaphragm after 20% strain is greater than 70%. According to the technical scheme, the problem that the thermoplastic elastomer vibrating diaphragm is poor in recovery rate after being vibrated at a high temperature or for a long time can be solved, the vibrating diaphragm can be uniform in thickness and smooth in forming in the air pressure forming process, and therefore it is guaranteed that the vibrating diaphragm has good acoustic performance.

Description

technical field [0001] The invention relates to the technical field of electro-acoustic conversion, in particular to a vibrating membrane and a sound-generating device. Background technique [0002] At present, the diaphragm in the sound generating device usually adopts a thermoplastic elastomer diaphragm, such as a thermoplastic polyurethane elastomer and a thermoplastic polyester elastomer diaphragm. Because thermoplastic polyurethane elastomer and thermoplastic polyester elastomer diaphragm have good plasticity, damping and temperature resistance, with the high demand for high power and high sound quality of speakers, thermoplastic elastomer diaphragm has been widely used in the field of speakers. Promote the application. However, the thermoplastic elastomer diaphragm is often formed by air pressure, and the stretching is uneven during the molding process, resulting in uneven thickness of the diaphragm after molding and uneven molding, resulting in a decrease in the yiel...

AI Technical Summary

Problems solved by technology

However, thermoplastic elastomer diaphragms are often molded by air pressure, and the stretching is uneven during the molding process, resulting in uneven thickness of the diaphragm after molding and uneven molding, which leads to a decrease in the yield of the diaphragm and affects the acoustic performance; On the other hand, due to the linear structure of the thermoplastic elastomer diaphragm, on the one hand, under large strains, the molecules are prone to slip, the viscous part increases, and the loss increases. After the external force is removed, the unrecoverable part increases and the resilience Poor, the acoustic performance of the loudspeaker using this diaphragm becomes worse after large-displacement vibration and high-demand waterproof test; moreover, during the long-term high-temperature force test, the molecular chain is stretched at high temperature for a long time, and the molecular chain moves at high temperature Increased capacity makes slippage more likely to occur. After the external force is removed, the recovery rate becomes poor, which makes the diaphragm deformed after the reliability of the speaker using this diaphragm, resulting in poor performance and even the risk of membrane rupture.

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