| 摘要 |
<p>PROBLEM TO BE SOLVED: To obtain a high muffling effect while lowering the wall as low as possible. SOLUTION: A muffling wall 21 is erected at the position separating a specific distance in the muffling object direct direction from an air-conditioner outdoor machine 11, and a roof 13 is erected to the air-conditioner outdoor machine 11 from the upper end part of the muffling wall 21. In this case, the inner part of the muffling wall 21 is made in a duct 25 opening its upper surface, and an active noise control system which consists of a speaker 26, an error microphone 27, a detecting microphone 28, and a controller 29, is attached to the duct 25. And a duct 31 is erected at the upper part of the air-conditioner outdoor machine 11, and an active noise control system which consists of a detecting microphone 32, a speaker 33, an error microphone 34, and the controller 29, is attached to the duct 31.</p> |
