Axial blade slot pressure face with undercut

Abstract

A blade and disk assembly includes a blade body and a disk body having a slot to receive the blade body. The blade body has a blade bearing surface. The slot has a disk bearing surface that contacts the blade bearing surface at a bearing interface. The slot has an undercut surface that is spaced apart from the blade body. An angle between the disk bearing surface and a line tangent to the undercut surface is at least 70 degrees.

1 . A blade and disk assembly comprising:
 a blade body having a blade bearing surface;   a disk body including at least one slot to receive said blade body, said slot having a disk bearing surface that contacts said blade bearing surface at a bearing interface, and said slot having an undercut surface that is spaced apart from said blade body, and wherein an angle between said disk bearing surface and a line tangent to said undercut surface is at least 70 degrees.   
   
   
       2 . The blade and disk assembly according to  claim 1  wherein said angle is less than 90 degrees. 
   
   
       3 . The blade and disk assembly according to  claim 1  wherein said undercut surface transitions directly from said disk bearing surface to form an undercut in said slot. 
   
   
       4 . The blade and disk assembly according to  claim 3  wherein said undercut surface comprises a curved surface and said disk bearing surface comprises a linear surface. 
   
   
       5 . The blade and disk assembly according to  claim 4  wherein said blade bearing surface comprises a linear surface. 
   
   
       6 . The blade and disk assembly according to  claim 3  wherein said line tangent to said undercut surface is defined at a location where said undercut surface transitions from said disk bearing surface. 
   
   
       7 . A gas turbine engine comprising:
 a fan;   a compressor section;   a combustor; and   a turbine section wherein said compressor and said turbine sections each include a disk body having a plurality of slots with each slot receiving one blade, and wherein at least one of said plurality of slots includes a first bearing surface that contacts a second bearing surface on a corresponding blade at a bearing interface, said slot having an undercut surface that is spaced apart from said corresponding blade, and wherein an angle between said first bearing surface and a line tangent to said undercut surface is at least 70 degrees.   
   
   
       8 . The gas turbine engine according to  claim 7  wherein said undercut surface transitions directly from said first bearing surface to form an undercut in said slot. 
   
   
       9 . The gas turbine engine according to  claim 8  wherein said line tangent to said undercut surface is defined at a location where said undercut surface transitions from said first bearing surface. 
   
   
       10 . The gas turbine engine according to  claim 9  wherein said undercut surface comprises a curved surface and said first bearing surface comprises a linear surface. 
   
   
       11 . The gas turbine engine according to  claim 10  wherein said second bearing surface comprises a linear surface. 
   
   
       12 . The gas turbine engine according to  claim 7  wherein said angle is less than 90 degrees.