Guide blade arrangement for an exhaust gas turbocharger

Abstract

A guide blade arrangement for an exhaust gas turbocharger may include guide blades rotatably mounted on a guide blade carrier ring via a respective blade bearing pin. A cover disc may be spaced from the guide blade carrier ring, wherein the guide blades may be arranged between the cover disc and the guide blade carrier ring. The cover disc may include a ceramic material, and the ceramic material may have a higher thermal conductivity in relation to at least one of the guide blade carrier ring, the guide blades, and the respective blade bearing pin.

1 . A guide blade arrangement for an exhaust gas turbocharger, comprising:
 guide blades rotatably mounted on a guide blade carrier ring via a respective blade bearing pin,   a cover disc that is spaced from the guide blade carrier ring, wherein the guide blades are arranged between the cover disc and the guide blade carrier ring,   wherein the cover disc includes a ceramic material, and   wherein the ceramic material has a higher thermal conductivity in relation to at least one of the guide blade carrier ring, the guide blades, and the respective blade bearing pin.   
     
     
         2 . The guide blade arrangement according to  claim 1 , wherein the ceramic material has a thermal conductivity of at least 120 W/mK. 
     
     
         3 . The guide blade arrangement according to  claim 1 , wherein the ceramic material is one of silicon nitride and silicon carbide. 
     
     
         4 . The guide blade arrangement according to  claim 1 , wherein at least one of the guide blade carrier ring, the guide blades, and the blade bearing pins are produced from a metal which has a lower thermal conductivity than the thermal conductivity of the ceramic material. 
     
     
         5 . The guide blade arrangement according to  claim 4 , wherein the metal has a maximum thermal conductivity of 20 W/mK. 
     
     
         6 . The guide blade arrangement according to  claim 4 , wherein the metal is a steel. 
     
     
         7 . The guide blade arrangement according to  claim 1 , wherein the cover disc is formed entirely of the ceramic material. 
     
     
         8 . The guide blade arrangement according to  claim 1 , further comprising at least one spacer element, which is arranged coaxially to the blade bearing pin and holds the guide blade carrier ring spaced from the cover disc. 
     
     
         9 . An exhaust gas turbocharger for a motor vehicle, comprising:
 a guide blade arrangement including:
 guide blades rotatably mounted on a guide blade carrier ring via a respective blade bearing pin, 
 a cover disc that is spaced from the guide blade carrier ring, wherein the guide blades are arranged between the cover disc and the guide blade carrier ring, 
 wherein the cover disc includes a ceramic material, the ceramic material having a higher thermal conductivity in relation to at least one of the guide blade carrier ring, the guide blades, and the respective blade bearing pin, 
   a turbine housing with a housing wall facing the guide blade arrangement, on which the cover disc of the guide blade arrangement is arranged,   a bearing housing and   a spring element supporting itself on the bearing housing, wherein in the axial direction a pressure force is exerted on at least one spacer element via the guide blade carrier ring, said spacer element configured to push the cover disc against the turbine housing for axial fixing.   
     
     
         10 . (canceled) 
     
     
         11 . The guide blade arrangement according to  claim 2 , wherein the ceramic material is one of silicon nitride and silicon carbide. 
     
     
         12 . The guide blade arrangement according to  claim 1 , wherein the guide blade carrier ring, the guide blades, and the blade bearing pins are produced from metal which has a lower thermal conductivity than the thermal conductivity of the ceramic material. 
     
     
         13 . The guide blade arrangement according to  claim 3 , wherein at least one of the guide blade carrier ring, the guide blades, and the blade bearing pins are produced from metal which has a lower thermal conductivity than the thermal conductivity of the ceramic material. 
     
     
         14 . The guide blade arrangement according to  claim 5 , wherein the metal is steel. 
     
     
         15 . The guide blade arrangement according to  claim 12 , wherein the metal is steel. 
     
     
         16 . The guide blade arrangement according to  claim 1 , wherein the cover disc is formed entirely of ceramic material. 
     
     
         17 . The turbocharger according to  claim 9 , wherein the ceramic material has a thermal conductivity of at least 120 W/mK. 
     
     
         18 . The turbocharger according to  claim 9 , wherein the ceramic material is one of silicon nitride and silicon carbide. 
     
     
         19 . The turbocharger according to  claim 9 , wherein at least one of the guide blade carrier ring, the guide blades, and the blade bearing pins are produced from a metal which has a lower thermal conductivity than the thermal conductivity of the ceramic material. 
     
     
         20 . The turbocharger according to  claim 19 , wherein the metal has a maximum thermal conductivity of 20 W/mK. 
     
     
         21 . The turbocharger according to  claim 9 , wherein the cover disc is formed entirely of the ceramic material.