TURBOCHARGER HAVING PISTON-TYPE VARIABLE NOZZLE WITH INTEGRATED ACTUATION SYSTEM

摘要

A turbocharger (20) having a sliding piston type variable turbine nozzle includes a tubular piston (40) disposed in a bore (32) of the turbine housing and axially slidable relative to the turbine housing, the piston being slidable between a closed position and an open position for blocking the nozzle (36) opening by an amount dependent on axial positioning of the piston so as to regulate flow into the turbine wheel (30). The turbine housing (32) and piston (40) are structured and arranged to define a cavity (50) therebetween, and there are seals (52a, 52b) between the turbine housing and piston for sealing the cavity, the turbine housing (32) defining a passage (54) connecting with the cavity (50) and adapted to be connected with a fluid source such that application of differential fluid pressure through the passage to the cavity urges the piston to axially slide in the turbine housing.