Birch, Stewart, Kolasch & Birch, LLP
Active sound reduction apparatus and active noise insulation wall having same
An active noise insulation wall includes an active sound reduction apparatus disposed on an upper end surface of a noise insulation wall. The active sound reduction apparatus comprises a combination of an active acoustic control cell and a sound tube. The active acoustic control cell controls a coming noise such that a diffracted sound pressure component of the coming noise at the upper end surface of the noise insulation wall is actively reduced. The sound tube decreases a sound wave of a frequency different from a target frequency of the active acoustic control cell. Thus, the active noise insulation wall can effectively reduce noises including many frequency components.
Mitsubishi Heavy Industries, Ltd.
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G10K G10K G10K E01F G10K
inventional inventional inventional inventional inventional
Keizo Masaharu Susumu Takanori
Ohnishi Nishimura Teranishi Arai