| 摘要 |
A sound-absorptive or sound-moderating exhaust-gas conduit connects between the exhaust manifold of a forwardly mounted internal combustion engine of an automobile and a location at the rear of the vehicle. The exhaust conduit has a substantially constant outer diameter along the whole of its length and can be bent so as to impart thereto a configuration suitable for the automobile in question. The conduit includes a tubular core, comprising two coaxial, metal wire helices (11, 13) between which a metal-net sleeve (12) is held. The tubular core (1) is encircled along the whole of its length by a coaxial sound absorbent (2), comprising for example mineral wool, which in turn is embraced by an impervious casing (3). As a result of its construction the conduit can be bent or curved to desired configurations while retaining its free gas-through flow area. A method of manufacturing the tubular conduit comprises forming the core (1) by helically winding metal wires (11, 13) coaxially with one another while placing therebetween a helically wound net-web sleeve (12) with mutually adjacent turns of the sleeve overlapping one another, this core then being fitted with the absorbent and casing. |
