| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a silencer for a ventilating opening capable of carrying out noise reduction of a wide range of frequency components of outdoor noise while having a compact structure. <P>SOLUTION: The silencer for the ventilating opening is provided with an outside air passage 30 comprising of a first passage 31 linearly passing outside air flowing in from an inlet 10, a second passage 32 formed adjacent to the first passage 31 to double back from an end of the first passage 31, and linearly passing double-backed outside air, and a third passage 33 formed adjacent to the second passage 32 so as to double back from an end of the second passage 32, and linearly passing double-backed outside air, and a chamber space 34 continuous with an end of the third passage 33, and formed with the ventilating opening 8 communicated with the indoors. The outside air passage 30 is structured such that sound absorbing materials 41 and 42 are provided on at least two opposing faces, sound absorbing materials 43 and 45 are respectively provided on an outside air collision face of the first passage 31 end and an outside air collision face of the second passage end, and a sound absorbing material 47 is provided on a whole of the chamber space 34. <P>COPYRIGHT: (C)2007,JPO&INPIT |
