Patent ID: 7549508

Claim:
A muffler comprising: a shell main body that is formed in a cylinder with two openings opposite to each other being apart from each other in an axial direction of the shell main body by rolling a flat plate to have an inner shell portion and an outer shell portion where the inner and outer shell portions have an overlapped portion overlapping an inner end portion of the inner shell portion and an outer end portion of the outer shell portion so that the inner end portion is located at an innermost position of the cylinder of the shell main body and at an inner side of the outer end portion, the inner end portion forming a part of the openings; and a pair of end plates that are partially inserted in the openings of the shell main body and are fixed to the shell main body, wherein the inner end portion of the overlapped portion is formed with two cut-off portions at opening-side edges of the inner end portion, respectively, to avoid interference between the inner end portion and the end plates when the end plates are inserted into the openings of the shell main body, the cut-out portions being located at an inner side of the cylinder and contactable with inserting portions of the end plates.