Exhaust line allowing a faster triggering of the catalyst
AssigneeInstitut Francais du Petrole
InventorMichel Castagne
Life of this patent
Estimating the term…
Abstract
Device intended to improve the working of a catalyst (3) placed in the exhaust manifold of an internal-combustion engine, said exhaust manifold consisting of a tube (2) opening on one side into the collector (1) collecting the combustion gases coming from the cylinder(s) and covering with the other end thereof said catalyst (3). According to the invention, the device comprises: at least one pipe (8) inside said tube (2), having a first end (81) which opens in proximity to said catalyst (3), and a means (10) intended to selectively close the intertube volume (9) delimited between said inner pipe (8) and said tube (2) as a function of the temperature of the exhaust gases flowing onto said catalyst (3).
Claims7
A device for improving the working of a catalyst placed in the exhaust manifold of an internal-combustion engine, said exhaust manifold comprising a tube connected to one side of a collector collecting the exhaust gases coming from the engine and opening at the other end thereof onto an inlet cone of said catalyst, said device comprising:
- an inner pipe located inside said tube, said inner pipe being arranged coaxially with said tube and having a restricted section with respect to said tube, a small thickness and a first end opening in proximity of said catalyst, and
- means for selectively closing an intertube space delimited between said inner pipe and said tube, as a function of the temperature of the exhaust gases led towards said catalyst so that the exhaust gases warm up a central portion of the catalyst when the selective closing means closes the intertube space.
A device for improving the working of a catalyst placed in the exhaust manifold of an internal-combustion engine, said exhaust manifold comprising a tube connected comprising a tube connected to one side of a collector collecting the exhaust gases coming from the engine and opening at the other end thereof onto an inlet cone of said catalyst, said device comprising:
- an inner pipe located inside said tube, said inner pipe being arranged coaxially with said tube and having a restricted section with respect to said tube, a small thickness and a first end opening in proximity of said catalyst, and
- means for selectively closing an intertube space delimited between said inner pipe and said tube, as a function of the temperature of the exhaust gases led towards said catalyst, said selective closing means comprising an annular member whose section completely covers the inlet of said intertube space when the catalyst is not primed.
A device as claimed in any one of the previous claims, further comprising means for homogenizing the velocities of the exhaust gases at the inlet of said catalyst.
Dependencies are inferred from the claim text.