Exhaust device equipped with spark arrester

A muffler comprising a spark arrester and a main body, the main body has a tubular shape and has an inside in which the spark arrester is disposed, wherein

• the spark arrester includes a main body part and a flange part, said main body part having a net portion through which exhaust gas passes, said flange part having a diameter enlarged from the main body part and being formed of a spring member,
• the flange part includes:
• an annular member having a predetermined thickness;
• and a bent part, said bent part extending from a periphery of said annular member and being telescopically bent with respect to the annular member by elastic deformation in a direction along a flow of the exhaust gas,
• the main body includes a downstream-side portion and an upstream-side portion, the upstream-side portion is disposed at an upstream side of the downstream-side portion and has an inner diameter larger than an inner diameter of the downstream-side portion,
• the main body is formed with a size that is equal to or smaller than an inner diameter of the downstream-side portion and the main body is disposed inside the downstream-side portion,
• the flange part is formed with a size that is equal to or larger than the inner diameter of the downstream-side portion and the flange part is accommodated in a space formed inside the upstream-side portion, and
• in the direction along the flow of the exhaust gas, a length of the space is set to be greater than the predetermined thickness, to be equal to or less than a natural length of the bent part and to be a length to further allow the elastic deformation of the bent part by an exhaust gas pressure acting on the spark arrester, whereby the bent part is supported by the upstream-side portion.