Abstract: A turbocharger having a variable nozzle with stepped two-stage vanes (50), the variable nozzle comprising a tubular piston (70) disposed in the bore (44) of the turbine housing (38) such that the piston (70) is axially slidable adjacent to the vanes (50) that extend across the nozzle. Each vane defines a first vane stage (50a) proximate the free end of the vane, the second vane stage (50b) having a different aerodynamic contour in comparison with the first vane stage (50a), each vane comprising a step (60) transitioning from the first vane stage (50a) to the second vane stage (50b). The piston (70) in a closed position closes the second vane stage (50b) so that exhaust gas flows only through the first vane stage (50a). The second vane stage (50b) is progressively opened as the piston (70) is axially slid toward an open position.

Abstract: A turbocharger includes a thin-walled insert installed in the bore of the turbine housing. The insert is generally ring-shaped and is radially resilient. The insert can be made of sheet metal formed into a ring shape, and in some embodiments is a split ring. A piston is axially slidable in the bore for varying the size of the turbine nozzle. The outer surface of the piston slides against the inner surface of the insert, and in preferred embodiments a piston ring that encircles the piston engages the inner surface of the insert to substantially seal the interface between the insert and the piston.

Abstract: A turbocharger having a variable nozzle with stepped two-stage vanes (50), the variable nozzle comprising a tubular piston (70) disposed in the bore (44) of the turbine housing (38) such that the piston (70) is axially slidable adjacent to the vanes (50) that extend across the nozzle. Each vane defines a first vane stage (50a) proximate the free end of the vane, the second vane stage (50b) having a different aerodynamic contour in comparison with the first vane stage (50a), each vane comprising a step (60) transitioning from the first vane stage (50a) to the second vane stage (50b). The piston (70) in a closed position closes the second vane stage (50b) so that exhaust gas flows only through the first vane stage (50a). The second vane stage (50b) is progressively opened as the piston (70) is axially slid toward an open position.

Abstract: A turbocharger having a sliding piston assembly comprising a tubular piston disposed in the bore of the turbine housing such that the piston is axially slidable relative to the turbine housing. The piston assembly further comprises a tubular carrier inserted axially into the bore of the turbine housing surrounding the piston and fixed against axial movement relative to the turbine housing, a radially outer surface of the carrier engaging an inner surface of the bore and a radially inner surface of the carrier being slidably engaged by a radially outer surface of the piston. The carrier defines an axial split extending a length of the carrier, and the carrier is resiliently flexible. Accordingly, the axial split allows the carrier to expand and contract in diameter.

Abstract: The present invention provides a long route (i.e., low pressure) EGR system adapted for use in an internal combustion engine, the system providing for a variable mixture of EGR gas and fresh air supply to a turbocharger compressor for delivery to the engine intake manifold and further provides a variable geometry mixer for use in the system.

Abstract: A turbocharger having a sliding piston assembly comprising a tubular piston disposed in the bore of the turbine housing such that the piston is axially slidable relative to the turbine housing. The piston assembly further comprises a tubular carrier inserted axially into the bore of the turbine housing surrounding the piston and fixed against axial movement relative to the turbine housing, a radially outer surface of the carrier engaging an inner surface of the bore and a radially inner surface of the carrier being slidably engaged by a radially outer surface of the piston. The carrier defines an axial split extending a length of the carrier, and the carrier is resiliently flexible. Accordingly, the axial split allows the carrier to expand and contract in diameter.