TURBOCHARGER WITH VARIABLE-VANE TURBINE NOZZLE HAVING A BYPASS MECHANISM INTEGRATED WITH THE VANES

摘要

A turbocharger includes a variable turbine nozzle defined between a nozzle ring (38) and a pipe flange (56), and having a plurality of circumferentially spaced vanes (34) rotatably mounted on the nozzle ring such that the vanes are pivotable. Each vane includes an airfoil section and a disk section rigidly affixed to an end of the airfoil section, the disk section being disposed against a face of the pipe flange, each disk section having a plurality of perforations extending axially therethrough. The pipe flange (56) has a corresponding number of holes (59) for each disk section of the vanes (34), the holes being positioned such that as each vane is rotated the perforations in the disk sections and the holes in the pipe flange of the insert become aligned in some positions of the vanes, allowing exhaust gas to pass between the nozzle and a space on an opposite side of the pipe flange from the nozzle.