Patent ID: 7726443

Claim:
A muffler, comprising: a muffler body adapted to be attached to an engine and receive exhaust gas from the engine, the muffler body including an exhaust outlet through which exhaust gas received from the engine flows outward; and a diffuser that covers the exhaust outlet of exhaust gas provided on the muffler body such that the exhaust gas passes into the diffuser, the diffuser being arranged to lower a temperature of the exhaust gas as the exhaust gas passes therethrough, wherein the diffuser includes a diffusion space to diffuse the exhaust gas passing therethrough, and an exhaust surface on which a plurality of exhaust holes for exhausting the diffused exhaust gas are formed, the exhaust surface facing the exhaust outlet, and wherein an opening rate provided by the exhaust holes of the exhaust surface is gradually increased toward an outer periphery of the exhaust surface from a portion of the exhaust surface opposite the exhaust outlet.