Turbine airfoil platform platypus for low buttress stress

Abstract

A blade is provided for use in a gas turbine engine. The blade has a platform, an airfoil portion extending radially from a first side of the platform, and an attachment portion extending from a second or underside side of the platform. The attachment portion includes a buttress which abuts the second side of the platform. The blade is provided with additional material on the second side of the platform for redistributing load away from the buttress.

1 . A blade for use in a gas turbine engine comprising: 
 a platform, an airfoil portion extending radially from a first side of the platform, and an attachment portion extending from a second side of the platform;    said attachment portion including a buttress which abuts said second side of the platform; and    means for redistributing load away from the buttress.    
   
   
       2 . The blade of  claim 1 , wherein said platform has a suction side and a pressure side and wherein said load redistributing means comprise means for directing the load outwardly towards a center of a leading edge root face.  
   
   
       3 . The blade of  claim 1 , wherein said platform has a leading edge and a thickness at said leading edge and wherein said load redistributing means includes a first region having a first thickness greater than said thickness at said leading edge and a second region having a second thickness greater than said first thickness.  
   
   
       4 . The blade of  claim 3 , wherein said platform has a central longitudinal axis and said first and second regions are offset from said central longitudinal axis.  
   
   
       5 . The blade of  claim 4 , wherein said first region is near the leading edge of said platform and said second region abuts said buttress.  
   
   
       6 . The blade of  claim 1 , wherein said platform has a suction side with a thickness and said means for redistributing said load comprises a third region offset from a central point of said buttress and said thickness in said third region is greater than said thickness at said suction side.  
   
   
       7 . The blade of  claim 6 , wherein said platform has a thickness which increases from said suction side to said third region.  
   
   
       8 . The blade of  claim 6 , wherein said platform has a pressure side with a thickness and said thickness at said third region is greater than said thickness at said pressure side.  
   
   
       9 . The blade of  claim 8 , wherein said thickness of said platform increases from said pressure side to said third region.  
   
   
       10 . The blade according to  claim 1 , wherein said load redistributing means comprises additional material located on the second side of the platform.  
   
   
       11 . The blade according to  claim 1 , wherein said second side is an underside of said platform.  
   
   
       12 . A turbine blade comprising: 
 a platform having a first side, a second side, a pressure side, a suction side and a leading edge;    an airfoil portion radially extending from said first side of said platform;    an attachment portion including a neck portion extending from the second side of said platform;    a buttress positioned adjacent an intersection of said neck portion and said second side;    a system for distributing loads away from said buttress;    said distributing system comprising additional material formed on the second side of said platform.    
   
   
       13 . The turbine blade according to  claim 12 , further comprising; 
 said additional material beginning at a first point near said leading edge and increasing in thickness to a second point abutting said buttress;    said additional material beginning at a third point adjacent said suction side and increasing in thickness from said third point to said second point; and    said additional material further beginning at a fourth point adjacent said pressure side and increasing in thickness from said fourth point to said second point.    
   
   
       14 . The turbine blade according to  claim 13 , further comprising said platform having a central longitudinal axis and said second point being offset from said central longitudinal axis.  
   
   
       15 . The turbine blade according to  claim 14 , wherein said first point is offset from said central longitudinal axis.  
   
   
       16 . The turbine blade according to  claim 12 , wherein said airfoil portion is an overhung airfoil portion.