| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a method of reducing the noise of an air duct that implements an excellent noise reduction effect, easy moldability and suitability for a clean room. <P>SOLUTION: A platelike or cylindrical sound absorbing material formed by laminating a surface skin material formed of dust-free paper or the like on at least one face of an organic fiber nonwoven fabric is installed in the air duct approximately at right angles to the length of the duct with the surface of the surface skin material positioned against an air flow or for contact with an air flow. Where the overall length of the duct is 100 parts, at least one sound absorbing material is installed in a position 20 to 50 parts apart from the upstream end, and the contact area of the surface skin material surface of the sound absorbing material with air is set to 1/2 to 4/5 of the cross sectional area of the duct, and the overall inside wall surface of the duct is lined with the sound absorbing material to further reduce the noise. <P>COPYRIGHT: (C)2007,JPO&INPIT |
