Patent ID: 8011471

Claim:
An exhaust chamber for a motor vehicle exhaust line, the exhaust chamber ( 1 ) comprising: a main envelope ( 2 ) defining a main enclosure ( 4 ) and having an exhaust gas inlet ( 6 ) and an exhaust gas outlet ( 8 ), the main envelope ( 2 ) comprising a rolled sleeve ( 26 ) having a longitudinal central axis and defining mutually axially opposite upstream and downstream openings, said rolled sleeve being made of a single unitary sheet of metal rolled around the central axis, said sheet having two longitudinal edges joined together and secured to one another, the sleeve having a closed cross section perpendicularly to the central axis, and at least one saucer-shaped shell ( 20 ) having an opening defined by a peripheral edge ( 22 ) of the shell ( 20 ), the or each shell ( 20 ) being tightly connected to an outside surface ( 24 ) of the sleeve ( 26 ) of the main envelope ( 2 ) along the peripheral edge ( 22 ), the shell ( 20 ), with the sleeve ( 26 ), defining a secondary enclosure ( 40 ), the sleeve of the main envelope ( 2 ) having, beneath the shell ( 20 ), a plurality of perforations ( 48 ) for placing the main enclosure ( 4 ) in communication with the secondary enclosure ( 40 ), wherein the sleeve ( 26 ) of the main envelope ( 2 ) has, in a first area located beneath the shell ( 20 ), at least one slot ( 52 , 54 , 56 ) for increasing the elasticity of said first area, and/or the sleeve ( 26 ) the main envelope ( 2 ) has, in a second area that is not covered by the shell ( 20 ), at least one rib ( 58 , 60 , 62 , 64 , 72 , 74 ) for increasing the stiffness of said second area.