Patent ID: 8465261

Claim:
A turbocharger ( 1 ) comprising: a compressor ( 8 ), which has a compressor wheel ( 9 ) which is fixed on one end of a rotor shaft ( 6 ); a turbine ( 2 ), which has a turbine rotor ( 10 ), which comprises a turbine wheel ( 5 ) which has a connecting journal ( 17 ) which is connected to a connecting section ( 12 ) of the rotor shaft ( 6 ); and at least two piston ring grooves ( 11 , 11 ′), arranged on the connecting journal ( 17 ) of the turbine rotor ( 10 ), wherein the connecting journal ( 17 ) of the turbine wheel ( 5 ) has a cylindrical cavity ( 15 ), the depth (L) of which is smaller than a length (B) of the connecting journal ( 17 ), measured from an axial shaft-side end face ( 14 ) of the rotor shaft ( 6 ) to a wheel back ( 13 ) of the turbine wheel ( 5 ), and wherein the piston ring grooves ( 11 , 11 ′) surround the cavity ( 15 ).