Patent ID: 7613307
Filing Date: 2009-11-03
Classification: E01F,G10K

Abstract:
1. An active noise insulation wall having a plurality of active sound reduction apparatuses, each such apparatus comprising; an active acoustic control cell, disposed on an upper end surface of a noise insulation wall, for controlling a coming noise such that a diffracted sound pressure component of the coming noise at the upper end surface is actively reduced; and at least one sound tube of a length determined based on a wave length of a sound wave to be decreased by the at least one sound tube, the at least one sound tube being provided on a side of the active acoustic control cell facing a sound source to be subjected to sound reduction, or on a side of the active acoustic control cell opposite to the sound source, or on both of the sound source side and the opposite side of the active acoustic control cell; the active sound reduction apparatuses being disposed in a row along a longitudinal direction of an upper end surface of a noise insulation wall or a side surface of an upper portion of the noise insulation wall, and wherein the at least one sound tube has a bottom portion buried in a depression formed in the noise insulation wall while maintaining a thickness of the noise insulation wall.