公开(公告)号：US6041125A

公开(公告)日：2000-03-21

申请号：US769381

申请日：1996-12-19

申请人： Masaharu Nishimura ,  Keizo Ohnishi ,  Chiaki Yasuda ,  Shinichiro Kajii ,  William P. Patrick ,  Anthony C. Zander

发明人： Masaharu Nishimura ,  Keizo Ohnishi ,  Chiaki Yasuda ,  Shinichiro Kajii ,  William P. Patrick ,  Anthony C. Zander

IPC分类号： E01F8/00 ,  E04B1/82 ,  G10K11/172 ,  G10K11/178 ,  A61F11/06

CPC分类号： G10K11/172

摘要： An active acoustic wall has sound-pressure detectors provided within respective cells so that a detected signal acts to oscillate an oscillation plate in the cell. A porous material on a surface is thereby provided with a high sound absorption coefficient over a wide frequency range. A space between a porous material or a perforated plate 1 on the surface and a back material fixed on a back side is divided into a plurality of sections so as to form cells 10 containing an air layer or a porous sound-absorbing material. Oscillation plates 6 are arranged within respective cells 10 so as to be driven for oscillation by oscillation-plate driving units 5. Sound-pressure detectors 7 are provided close to the porous material 1 in the cell 10 so that a detected signal is inputted to a signal-processing unit 8. The signal processing unit 8 outputs a signal to the driving unit 5 for oscillating the oscillation plate 6 such that an output of the sound-pressure detector is minimized. The sound pressure on the surface of the porous material 1 is minimized at all frequencies. The velocity of particles on the surface becomes large so that the particles are turned into thermal energy, thereby providing a high sound-absorption coefficient.

摘要翻译： 主动声学墙具有设置在各个单元内的声压检测器，使得检测信号用于振荡单元中的振荡板。 由此，在宽的频率范围内，表面上的多孔材料具有高吸声系数。 表面上的多孔材料或多孔板1之间的空间和固定在背面的背面材料被分成多个部分，以形成包含空气层或多孔吸声材料的电池10。 振荡板6布置在各个电池单元10内，以便被振荡板驱动单元5驱动以进行振荡。声压检测器7设置在电池单元10中靠近多孔材料1的位置，从而将检测信号输入到 信号处理单元8.信号处理单元8向驱动单元5输出振荡振荡板6的信号，使得声压检测器的输出最小化。 在多孔材料1的表面上的声压在所有频率下被最小化。 表面上的颗粒的速度变大，使得颗粒变成热能，从而提供高的吸声系数。