SOUND-DAMPING SYSTEM

WIPO Patent Application WO/2019/009342

A1

Provided is a highly versatile sound-damping system with which it is possible to combine high ventilation performance and sound-proofing performance, and with which it is possible to dampen a plurality of resonant sounds, and which does not require design to be made to correspond to a ventilation sleeve. The sound-damping system has a sound-damping device provided to a ventilation sleeve, and the sound-damping device damps sound having the first resonant frequency of the ventilation sleeve. The sound-damping device is equipped with: a sound damper having a cavity portion and an opening portion, and is positioned one end side surface of a wall; and a sound-absorbing material positioned at a position inside the cavity portion or covering the opening portion. The opening portion of the sound damper is positioned facing the central axis side of the ventilation sleeve, and the depth Ld of the cavity portion in the direction of propagation of sound waves within the sound damper is greater than the width Lo of the opening portion in the width direction of the ventilation sleeve. If the wavelength of the sound waves having the first resonant frequency of the ventilation sleeve is defined as λ, the depth Ld of the cavity portion satisfies the condition 0.011×λ