Tribologically improved design for variable stator vanes
AssigneeGeneral Electric Company
InventorRobert W. Bruce
Life of this patent
Estimating the term…
Abstract
A bushing and washer forming a bearing assembly at the outer radial end of a stator vane, the outer bearing assembly, and the bearing assembly at the inner radial end of the stator vane, the inner bearing assembly, that facilitate durability, effectiveness and reduced cost. Both the inner and outer bearing assemblies are designed to rotate relative to the vane shaft and the respective mating shroud or case to even out the wear around the circumference of the bushing. When a rotating bushing is used, a flange on the bushing is designed to be positioned on the inside of the case, so that a pressure differential across the case applies a force to the vane to move it outwardly against the flange and the flange against the case, thereby minimizing air leakage.
Claims23
A bearing assembly for rotatively positioning a variable vane to an engine casing comprising a bushing wherein a first surface of the bushing contacts a variable vane stem;
- a second opposed surface of the bushing contacts the engine casing, and, upon installation of the bushing, the bushing rotates relative to the variable vane stem and engine casing.
A variable vane assembly for a gas turbine engine comprising:
- a variable vane, the vane including a first vane stem at a first vane end and a second vane stem at a second, opposing vane end positioned radially inward toward a center line of the engine;
- a first bearing assembly for rotatively positioning the first vane stem within an outer engine casing;
- a second bearing assembly for rotatively positioning the second vane stem within an inner engine shroud;
- and
- a lever arm fixedly attached to the first vane stem for variably altering an angular orientation of a vane airfoil;
- the first bearing assembly having a first bushing with an inner diameter wherein the inner diameter of the bushing contacts the first vane stem at the first vane end, and the outer diameter of the bushing contacts the outer engine casing, the bushing preventing contact between the outer engine casing and the first vane stem, the bushing providing a wear surface as the variable vane assembly is moved from a first position to a second position;
- the second bearing assembly having a second bushing with an inner diameter wherein the inner diameter of the bushing contacts the second vane stem at the second end positioned radially inward from the first vane end, and the outer diameter of the bushing contacts the outer engine casing, the bushing preventing contact between a seal and the second vane stem, the bushing providing a wear surface as the variable vane assembly is moved from a first position to a second position;
- and
- wherein at least one of the first bushing and the second bushing rotates relative to its respective vane stem.
Dependencies are inferred from the claim text.