STRUCTURE AND METHOD FOR BONDING NOZZLE VANE AND LEVER, AND VARIABLE-CAPACITY TURBOCHARGER

摘要

An object is to provide a structure and a method of joining a nozzle vane and a lever, and a variable geometry turbocharger, capable of reducing breakage of a welded part between a shaft portion of the nozzle vane and the lever during usage of the same by reducing generation of a hot crack in weld metal at the welded part. A joint structure includes: a nozzle vane 2 disposed in an exhaust passage for guiding exhaust gas to a turbine wheel 34 of a variable geometry turbocharger 500, and including a shaft portion 2a; and a lever 1 including a fitting surface 42a fitted with a peripheral surface 72 on one end side of the shaft portion, for transmitting torque to the shaft portion to adjust a vane angle of the nozzle vane. Weld metal 50 at a welded part 40 between the lever and the nozzle vane is formed so that a center position 64 of the weld metal is disposed inside a position 17 of the fitting surface with respect to a radial direction of the shaft portion.