Abstract: A turbocharger comprises a shaft connecting a turbine wheel, which is disposed in a turbine housing, to an impeller wheel. Between the two is a bearing system having a bearing housing and bearings for the shaft disposed therein. The shaft is fitted with at least one heat insulation between the turbine wheel and the bearing system, of which the heat conductivity is lower than that of the portions of the shaft which are adjoining said insulation and which hampers heat transmission through the shaft.

Abstract: The invention concerns an exhaust gas turbocharger (1) having a shaft (2) on which a turbine wheel (4) and a compressor wheel (3) sit and which is guided in radial bearings (5, 6) and in at least one axial bearing (9), which is characterized in that the radial bearings (5, 6) are embodied as passive magnetic bearings having permanent magnets (23 through 31) generating axial magnetic fluxes; and the axial bearing (9) is embodied as an active magnetic bearing having an electromagnet (55), an axial sensor, and a controller for controlling the electrical current impinging upon the electromagnet (55).