| 摘要 |
PURPOSE: A noise reduction having a duplex type structure is provided to efficiently seclude noise by reflecting or diffract the noise came into inside at a space where sound-absorbing materials are installed. CONSTITUTION: A noise reduction having a duplex type structure comprises a noise catcher body, a plurality of noise cutoff plate(200), and an inner sound absorbing material(300). One side of the noise catcher body is opened and a closed other side of the noise catcher body reflects and diffracts noise came into the inside space. The noise cutoff plates are installed in the outer side of the noise cutoff plate body and comprise a plurality of noise reflection projections. The noise reflection projections primarily reflect the noise and diffracts. The inner sound absorbing material absorbs the noise and secondarily diffracts the noise. |
