Variable stator vane arrangement

Abstract

A variable guide vane assembly comprising a variable guide vane having an aerofoil and a spindle at one end of the aerofoil; wherein the vane further comprises a platform positioned between the aerofoil and the spindle, the platform having a surface facing in the direction of the spindle and at least one side face; the assembly also having a washer with an aperture through which the spindle extends, the washer having a portion which overhangs the at least one side face.

1 . A variable guide vane assembly comprising a variable guide vane having an aerofoil and a spindle at one end of the aerofoil;
 wherein the vane further comprises a platform having a non-circular plan positioned between the aerofoil and the spindle, the platform having a surface facing in the direction of the spindle and at least one side face;   the assembly also having a washer having a circular plan with an aperture through which the spindle extends, the washer having a portion which overhangs the at least one side face.   
     
     
         2 . A variable guide vane assembly according to  claim 1 , wherein the washer is supported by the platform surface. 
     
     
         3 . A variable guide vane assembly according to  claim 1 , wherein the plan of the platform is rectangular. 
     
     
         4 . A variable guide vane assembly according to  claim 1 , wherein the plan of the platform is fluted. 
     
     
         5 . A variable guide vane assembly according to  claim 1 , wherein the washer is formed from plastic. 
     
     
         6 . A variable guide vane assembly according to  claim 5 , wherein the washer is formed from polyimide. 
     
     
         7 . A variable guide vane assembly according to any of  claims 1 , wherein the washer is formed from metal having a surface coating. 
     
     
         8 . A variable guide vane assembly according to  claim 1 , further comprising a casing having a chamber containing the platform and the washer. 
     
     
         9 . A variable guide vane assembly according to  claim 8 , wherein the chamber is stepped from a casing surface wherein a surface of the platform opposing the spindle facing surface is flush with the casing surface. 
     
     
         10 . A variable guide vane assembly comprising a variable guide vane having an aerofoil and a spindle at one end of the aerofoil;
 wherein the vane further comprises a platform having a rectangular plan positioned between the aerofoil and the spindle, the platform having a surface facing in the direction of the spindle and at least one side face;   the assembly also having a washer having a circular plan with an aperture through which the spindle extends, the washer having a portion which overhangs the at least one side face;   wherein the washer is supported by the platform surface.   
     
     
         11 . A variable guide vane assembly according to  claim 10 , further comprising a casing having a chamber containing the platform and the washer. 
     
     
         12 . A variable guide vane assembly according to  claim 11 , wherein the chamber is stepped from a casing surface wherein a surface of the platform opposing the spindle facing surface is flush with the casing surface.