Patent ID: 8104571
Filing Date: 2012-01-31
Classification: F01N,Y10T

Abstract:
1. An external cylinder used for a silencer, having an internal cylinder acting as a primary passage of an exhaust gas, and an acoustic absorbent provided outside said internal cylinder, said external cylinder comprising: a tubular body formed from a resin material; a metallic layer provided on an inner surface of said tubular body; an anterior covering portion provided on an inner circumferential surface of an anterior end of said external cylinder to cover an anterior portion of said metallic layer; and a posterior covering portion provided on an inner circumferential surface of a posterior end of said external cylinder to cover a posterior portion of said metallic layer, wherein an anterior end of said metallic layer is formed so as to be located posterior to the anterior end of said external cylinder and anterior to a posterior end of a coupling body inserted into the anterior end of said external cylinder, while a posterior end of said metallic layer is formed so as to be located anterior to the posterior end of said external cylinder and posterior to an anterior end of a tail cap inserted into the posterior end of said external cylinder.