摘要 |
A two-stage supercharging device for an internal combustion engine having a radial high-pressure turbine and an axial low-pressure turbine. The high-pressure turbine has spiral housing with an exhaust-gas inlet connecting piece connected to an exhaust line and via which an exhaust-gas flow flows from the internal combustion engine to the high-pressure turbine. A partial flow of the exhaust-gas flow can flow past the high-pressure turbine in a bypass unit and can be adjusted by a shut-off valve. The bypass unit includes a branch line and an annular duct housing which are integrally formed on the spiral housing as a single-piece component. The branch line branches off the exhaust-gas inlet connecting piece at a branching point and issues into an annular duct formed by the annular duct housing. The shut-off valve is arranged, at the branching point. The partial exhaust-gas flow flows through the branch line into the annular duct and from there through an axially arranged annular gap into an exhaust-gas duct. There, the partial exhaust-gas flow merges with a main exhaust-gas flow emerging from the high-pressure turbine and flows together therewith into the low-pressure turbine. |