Patent ID: 8267647

Claim:
A turbocharger comprising: a turbine housing ( 100 ); a vane ring assembly, comprising a lower vane ring ( 20 , 21 , 22 , 23 ), an upper vane ring ( 30 , 31 ), one or more guide vanes ( 80 ) pivotably mounted at least partially between said lower and upper vane rings, and at least one spacer ( 50 ) positioned between said lower and upper vane rings ( 20 , 30 ) for maintaining a distance between said lower and upper vane rings ( 20 , 30 ); one or more fasteners ( 190 ) attaching said lower vane ring ( 20 ) to said turbine housing ( 100 ) but not to said upper vane ring ( 30 ), and one or more fastener assemblies ( 191 , 43 ) attaching said lower vane ring ( 20 ) to said upper vane ring ( 30 ) but not to said turbine housing ( 100 ), wherein said lower vane ring ( 20 ) has radial elongate through holes or peripherally open slots through which the one or more fasteners ( 190 ) for attaching said lower vane ring ( 20 ) to said turbine housing ( 100 ) extend, said elongate holes or peripherally open slots maintaining concentricity yet allowing for thermal expansion of the lower vane ring ( 20 , 21 , 22 , 23 ).