Patent ID: 8177024

Claim:
Acoustic attenuation device for an intake line of an internal combustion engine, said device being intended to have a flow of pressurized gaseous fluid passing through it and comprising: a conduit structure which has a tubular wall ending in two ends, these respectively being the fluid inlet and fluid outlet ends, which are able to be incorporated into said intake line, and at least one resonance chamber forming a Helmholtz resonator which is arranged on the outside of this conduit structure and which communicates therewith via at least one opening formed in said wall for the passage of the fluid, the or each chamber being axially delimited by two partitions substantially transverse to the axial direction (A) of this structure, wherein the or each resonance chamber further comprises at least one gravity discharge orifice for discharging condensate carried along by the fluid, which orifice is formed in said wall in the immediate vicinity of one of said transverse partitions, the or each chamber being transversely delimited by two longitudinal walls which run parallel to the axial direction of the structure and are joined together by these transverse partitions thereby forming a housing which is closed off in a fluid tight manner by a cover formed as one piece with this housing and wherein said housing and said cover are formed as one piece with a radially external duct of said conduit structure thereby forming a one-piece assembly made of a plastic, at least one anti-creep metal ring, said anti-creep ring being a cylindrical tube having a tubular wall provided with said or each passage opening and with said or each discharge orifice being inserted against the radially internal face of this duct to allow it to withstand high operating temperatures, such that the fluid flowing along the inside of the or each ring communicates directly with the or each chamber opposite.