Vane assembly with trapped segmented vane structures

Abstract

A vane assembly includes inner and outer rings, a plurality of segmented vane structures circumferentially-spaced around a central axis and between the inner and outer rings, and at least one spring that mechanically traps the segmented vane structures in radial compression between the inner and outer rings.

What is claimed is: 
     
         1 . A vane assembly comprising:
 a radial stack of inner and outer rings and a plurality of segmented vane structures circumferentially-spaced between the inner and outer rings around a central axis, the radial stack being firmly secured together in radial compression exclusively by friction-fit between the inner and outer rings and the segmented vane structures.   
     
     
         2 . The vane assembly as recited in  claim 1 , wherein the inner and outer rings have a coefficient of thermal expansion differential selected with respect to thermo-mechanically trapping the segmented vane structures in radial compression between the inner ring and the outer ring. 
     
     
         3 . The vane assembly as recited in  claim 2 , wherein each of the plurality of segmented vane structures includes an airfoil and inner and outer platforms; and further comprising at least one distinct intermediate platform radially trapped between one of the inner and outer platforms and one of the inner and outer rings, wherein the at least one intermediate platform includes one or more interference-fit members configured to secure the plurality of segmented vane structures in the stack. 
     
     
         4 . The vane assembly as recited in  claim 3 , further comprising at least one spring mechanically trapping the segmented vane structures in radial compression between the inner and outer rings. 
     
     
         5 . The vane assembly as recited in  claim 4 , further comprising at least one wedge located radially between the segmented vane structures and at least one of the inner and outer rings such that the wedge causes compression of the at least one spring, and a retainer ring secured to at least one of the inner and outer rings adjacent the wedge, the retainer ring mechanically restricting axial movement of the wedge. 
     
     
         6 . The vane assembly as recited in  claim 2 , wherein the vane assembly includes a ceramic material. 
     
     
         7 . The vane assembly as recited in  claim 6 , wherein the ceramic material is a ceramic matrix composite. 
     
     
         8 . The vane assembly as recited in  claim 1 , wherein each of the plurality of segmented vane structures includes an airfoil and inner and outer platforms; and further comprising at least one distinct intermediate platform radially trapped between one of the inner and outer platforms and one of the inner and outer rings, wherein the at least one intermediate platform includes one or more interference-fit members configured to secure the plurality of segmented vane structures in the stack. 
     
     
         9 . The vane assembly as recited in  claim 8 , further comprising at least one spring mechanically trapping the segmented vane structures in radial compression between the inner and outer rings. 
     
     
         10 . The vane assembly as recited in  claim 9 , further comprising at least one wedge located radially between the segmented vane structures and at least one of the inner and outer rings such that the wedge causes compression of the at least one spring, and a retainer ring secured to at least one of the inner and outer rings adjacent the wedge, the retainer ring mechanically restricting axial movement of the wedge. 
     
     
         11 . The vane assembly as recited in  claim 9 , wherein each of the segmented vane structures is a monolithic piece including an airfoil and inner and outer platforms, each of the inner and outer platforms having a core gas-path surface, an opposed radial surface, and leading and trailing ends, and further including at least one distinct intermediate platform radially trapped between one of the inner and outer platforms and one of the inner and outer rings. 
     
     
         12 . The vane assembly as recited in  claim 11 , wherein the monolithic piece comprises a monolithic ceramic material. 
     
     
         13 . The vane assembly as recited in  claim 1 , further comprising at least one spring mechanically trapping the segmented vane structures in radial compression between the inner and outer rings. 
     
     
         14 . The vane assembly as recited in  claim 13 , wherein the inner and outer rings have a coefficient of thermal expansion differential selected with respect to thermo-mechanically trapping the segmented vane structures in radial compression between the inner ring and the outer ring. 
     
     
         15 . The vane assembly as recited in  claim 13 , further comprising at least one wedge located radially between the segmented vane structures and at least one of the inner and outer rings such that the wedge causes compression of the at least one spring, and a retainer ring secured to at least one of the inner and outer rings adjacent the wedge, the retainer ring mechanically restricting axial movement of the wedge. 
     
     
         16 . The vane assembly as recited in  claim 1 , wherein the vane assembly includes a ceramic material. 
     
     
         17 . The vane assembly as recited in  claim 16 , wherein the inner and outer rings have a coefficient of thermal expansion differential selected with respect to thermo-mechanically trapping the segmented vane structures in radial compression between the inner ring and the outer ring. 
     
     
         18 . The vane assembly as recited in  claim 16 , wherein the ceramic material is a ceramic matrix composite. 
     
     
         19 . The vane assembly as recited in  claim 18 , wherein the inner and outer rings have a coefficient of thermal expansion differential selected with respect to thermo-mechanically trapping the segmented vane structures in radial compression between the inner ring and the outer ring. 
     
     
         20 . The vane assembly as recited in  claim 16 , wherein each of the segmented vane structures is a monolithic piece including an airfoil and inner and outer platforms, each of the inner and outer platforms having a core gas-path surface, an opposed radial surface, and leading and trailing ends, and further including at least one distinct intermediate platform radially trapped between one of the inner and outer platforms and one of the inner and outer rings, and wherein the monolithic piece comprises a monolithic ceramic material.