Shut-off valve unit for a circuit for injecting air in the exhaust system of an internal combustion engine
AssigneeSagem SA
InventorBernard LaFleur
Life of this patent
Estimating the term…
Abstract
A shut-off valve unit for a circuit for injecting air into an exhaust system of an internal combustion engine has a casing (9, 29) with a first chamber (10), a second chamber (24) and a third chamber (27). The valve rod (18) forms a passage (43) for communicating air between the first chamber (10) and the second chamber (24). The opening and closing of valve (19) with respect to valve seat (21) is controlled by movement of the membrane (12); which also controls communication between the second chamber (24) and the third chamber (27).
Claims10
A shut-off valve unit for an air injection circuit in an exhaust system of an internal combustion engine, the shut-off valve unit comprising;
- a casing having a first chamber, a second chamber and a third chamber;
- a membrane delimiting the first chamber in said casing;
- means for admitting air into said first chamber from an air pump;
- means for admitting air into said second chamber from said air pump;
- means for evacuating air from said third chamber towards an exhaust manifold of said engine;
- a valve including a valve rod controlled by said membrane to allow communication between said second chamber and said third chamber when said air pump is in operation;
- wherein said means for admitting air into said first chamber includes a passage between said first and second chambers;
- and
- wherein said passage is formed in said valve rod.
Dependencies are inferred from the claim text.