摘要 |
<p>A muffler having a shell of a double-layer structure includes an inner shell that is formed by fixing ends of a tubularly rolled plate material to each other through a lock seam, and an outer shell that is formed substantially in the same manner as the inner shell. In this muffler, a through-hole is provided through the inner shell at a position where the inner shell overlaps with a lock seam portion of the outer shell.</p> |