JPS57124018A - Muffler for internal combustion engine - Google Patents

Abstract

PURPOSE:To reduce the quantity of a sound absorbent for a muffler provided at the outlet port of an exhaust pipe, by providing the sound absorbent between the outer and inner walls of a gas receiver whose one end is ckised and by providing the inner wall with numerous small holes. CONSTITUTION:Exhaust gas flows through the outlet port 16 of an exhaust pipe 10 and collides against the inner wall 22 of a gas receiver 18 so that the direction of proceeding of the gas is turned. After that, the gas flows through a passage 28 into a chamber 29 defined by partitions 34, 44. The exhaust noise is absorbed through the small holes 26 of the inner wall 22. Since the sound absorbent is made of steel wool, tar is not adsorbed on the absorbent. For that reason, the sound absorbing function of the absorbent does not deteriorate in a long time. The gas from the chamber 29 flows through a passage 31 defined by the outer wall 20 and body 14 of the gas receiver 18 and enters into a silender 38 through an inlet port 40 The gas thereafter goes out through an outlet port 42 and folws through a chamber 36 and a pipe 49 and passes through expansion chambers 48, 52, 58, 64 and holes 54, 60, 66 alternately so that the exhaust noise is reduced while expansion and contraction are repeated. Finally, the gas is released through a tailpipe 68.