Patent ID: 7628012

Claim:
A mixing device comprising: an inlet end able to be mated to an engine side exhaust pipe; an outlet end able to be mated to a tailpipe; a periphery; an interior; at least two exhaust passages, said at least two exhaust passages each being in fluid communication with said inlet end via a common closed-section inlet at said inlet end of said mixing device, and said at least two exhaust passages each being in fluid communication with said outlet end via individual closed-section outlets at said outlet end of said mixing device, said at least two exhaust passages being operable to bifurcate vehicle exhaust from said engine side exhaust pipe into at least two separate exhaust flow streams; at least two ambient air passages, said at least two ambient air passages being interposed between and partially surrounding said at least two exhaust passages, said at least two ambient air passages each being in fluid communication with openings in said periphery of said mixing device and said at least two ambient air passages being in fluid communication with said outlet end via a common outlet, said common outlet of said at least two ambient air passages being defined by the area outside of said individual closed-section outlets of said at least two exhaust passages and within said periphery of said mixing device; said at least two exhaust passages each having a discrete length; and said at least two exhaust passages having at least one central exhaust passage and at least two peripheral exhaust passages.