SOUND REDUCTION STRUCTURE FOR EXHAUST PIPE SUB-MUFFLER, AND EXHAUST PIPE SUB-MUFFLER

摘要

PROBLEM TO BE SOLVED: To provide a sound reduction structure for an exhaust pipe sub-muffler having heat resistance and heat insulation property, and capable of exhibiting high sound reduction performance with respect to a low frequency region of 1 kHz or less even when its thickness is thin.;SOLUTION: In a sound reduction structure disposed between an inner pipe and an outer pipe of an exhaust pipe sub-muffler having a coaxial double cylindrical structure of the inner pipe and the outer pipe, a first inorganic fiber elastic porous body, an intermediate layer composed of inorganic fiber cloth, and a second inorganic fiber elastic porous body are successively stacked in this order from the inner pipe side toward the outer pipe side in arrangement.;SELECTED DRAWING: None;COPYRIGHT: (C)2018,JPO&INPIT