| 摘要 |
PROBLEM TO BE SOLVED: To raise the sound absorbing effect of a sound absorbing panel with respect to sound of a low-frequency sound region without making the panel thicker. SOLUTION: A sound absorbing panel 1 is constituted into multilayered structure in which a porous plate 10, glass wool 12, a gas filling vessel 14 and a sound isolation plate 16 are closely stuck mutually in order from the front side of the panel and is made to be porous plate sound absorbing structure. Among these, the gas filling vessel 14 consists of high polymer films having high airtight, for example, such as multilayered polyethylene films, polypropylene films and it is constituted so as to transmit most sonic waves which hit each face of the films and to absorb a part of the waves. Moreover, hydrofluorocarbon 134a whose transmission speed of sound is small is enclosed in the vessel 14. COPYRIGHT: (C)2004,JPO
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