MANUFACTURING METHOD FOR MUFFLER

PROBLEM TO BE SOLVED: To provide a manufacturing method for a muffler by packing acoustic material in a gap portion uniformly at a high bulk density even when the gap portion has a long entire length and the gap is narrow, in regard to the manufacturing method for a muffler in which an outer shell forming part is arranged around an outer periphery of a gas flow passage forming part formed with a number of small holes and an acoustic material is provided in the gap portion between the parts. SOLUTION: The manufacturing method is for the muffler which comprises the gas flow passage forming passage 3 having the number of small holes 5, the outer shell forming part 2 disposed with the gap portion 4 around the outer periphery of the gas flow passage forming part 3 and the acoustic material 9 packed in the gap portion 4. In the manufacturing method for the muffler, air in the gap portion 4 is evacuated through the small holes partitioned by a partition means and the acoustic material 9 is packed into the gap portion 4 while the partition means is moved. COPYRIGHT: (C)2006,JPO&NCIPI