NOISE ATTENUATION DEVICE

摘要

PURPOSE: A noise attenuation apparatus is provided to effectively reduce noise which is under a fixed frequency by coupling a hollow tube with two or more side holes to a noise source. CONSTITUTION: A noise attenuation apparatus comprises two or more side holes(12) and a soundproofing member. The side holes vertically penetrates through a hollow tube(11) and has a smaller cross section than the hollow tube. Protrusions(13) are formed in the side holes and are outward protruded from the outer surface of the hollow tube. The soundproofing member covers the outer surface of the tube in order to block or inhale noise.