基于微振动理论单罩杯双自由度耳罩隔声模型

摘要

A single cup earmuff was simplified to a single cup and double degree-of-freedom vibration model. The model reveals the influence of earmuff’s stiffness, damping, mass, volume and foam absorption material on the sound insulation performance of the earmuffs. It shows that increasing the cup stiffness and reducing the stiffness of the absorption material in the cup are helpful for improving the sound insulation performance of the earmuffs. Higher damping coefficient of the cup can lead to smaller system resonance peak and better sound insulation performance in the low-frequency range. Smaller damping coefficient of sound absorbing material is better. Larger earmuff’s mass or volume can effectively improve the sound insulation performance of the earmuffs, but will reduce earmuff’s comfort.%把单耳罩结构考虑为单罩杯双自由度模型，揭示耳罩刚度、阻尼、质量、体积、泡沫类吸声材料对耳罩隔声的影响规律。该模型表明，提高罩杯刚度，降低罩杯内吸声材料的刚度，有利于提高耳罩的隔声性能。罩杯阻尼系数越高，系统共振峰越小，低频隔声性能有改善；吸声材料的阻尼系数较小为宜；较大的耳罩质量或体积，可以有效提高耳罩的隔声性能，但较大的质量或体积会导致耳罩舒适性降低。