Patent ID: 6672966
Filing Date: 2004-01-06
Classification: F01D,F16D

Abstract:
A toothed coupling mechanism for transmitting torque between rotating elements, said toothed coupling mechanism comprising:a curvic coupling having at least one male curvic coupling tooth and at least one female curvic coupling tooth, wherein said at least one male curvic coupling tooth matches said at least one female curvic coupling tooth, wherein said at least one male curvic coupling tooth has a first pressure surface and said at least one female curvic coupling tooth has a second pressure surface, wherein said at least one female curvic coupling tooth has a root, and wherein said at least one female curvic coupling tooth has a compound fillet formed between said second pressure surface and said root, wherein said compound fillet has a major fillet with a major radius and a minor fillet with a minor radius, said major radius is larger than said minor radius, said major fillet of said compound fillet is positioned in the root area of said at least one female curvic coupling tooth, and said minor fillet of said compound fillet is positioned between the major fillet and the second pressure surface of said at least one female curvic coupling tooth, wherein background hoop stresses act on the major fillet resulting in 10% to 30% lower normalized stress concentration factor, wherein said major radius and said minor radius are optimized using finite element analysis, and wherein, when said coupling mechanism is coupled, said compound fillet allows a clearance between said at least one female curvic coupling tooth and said at least one male curvic coupling tooth that matches said at least one female curvic coupling tooth, the clearance being the separation between the tangency point of the minor fillet with the second pressure surface and a tip surface of the male curvic coupling tooth.