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HIGH DURABILITY BUSHING ASSEMBLY FOR A VARIABLE STATOR VANE

IP.com Disclosure Number: IPCOM000246170D
Publication Date: 2016-May-12
Document File: 5 page(s) / 96K

Publishing Venue

The IP.com Prior Art Database

Abstract

In a gas turbine engine, a bushing for a variable stator vane is made of two pieces and incorporates a self-lubricating material. The bushing can be substituted for a conventional one-piece bushing.

This text was extracted from a PDF file.
This is the abbreviated version, containing approximately 49% of the total text.

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HIGH DURABILITY BUSHING ASSEMBLY FOR A VARIABLE STATOR VANE

ABSTRACT


[0001] In a gas turbine engine, a bushing for a variable stator vane is made of two pieces and incorporates a self-lubricating material. The bushing can be substituted for a conventional one-piece bushing.

BACKGROUND


[0002] This disclosure relates generally to gas turbine engines and more particularly to variable stator vanes in the compressor of such engines.


[0003] A gas turbine engine includes a compressor used to pressurize intake air which then flows to a downstream combustor and one or more turbines. A typical compressor includes a series of stages, each stage including a row of stationary stator vanes and a row of rotating compressor blades.


[0004] In some gas turbine engines, one or more stages of the stator vanes are variably actuated. An outer trunnion or spindle of each vane passes through the stator case and is coupled to a lever arm. The lever arms are coupled to an actuation ring that is connected to a vane actuator. The vanes are retained to the stator case using a bushing assembly comprising a combination of bushings, washers, and a lock nut that is threaded onto the outer trunnion.


[0005] Described herein is a configuration for a bushing assembly having a long life.

BRIEF DESCRIPTION OF THE DRAWINGS


[0006] The concept may be best understood by reference to the following description taken in conjunction with the accompanying drawing figures, in which:


[0007] FIG. 1 is a schematic cross-sectional view of a variable stator vane trunnion and

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conventional bushing assembly; and


[0008] FIG. 2 is a schematic cross-sectional view of a variable stator vane trunnion and bushing assembly using the concept described herein.

DETAILED DESCRIPTION OF THE CONCEPT


[0009] Illustrated in FIG. 1 is a schematic representation of a variable vane bushing assembly 10 as commonly found in existing gas turbine engines, for example in aircraft applications. The bushing assembly 10 is used for the purpose of mounting a vane 12 to an engine casing 14 so that the vane 12 is rotatable over a range of a few degrees about an axis "A". The vane 12 includes an airfoil 16 with a cylindrical trunnion 18 extending therefrom. An adapter 20 is mounted to the casing 14, and has a bore 22 passing therethrough.


[0010] A bushing 24 is provided which includes a cylindrical portion 26 and a radial flange 28 at an inboard end. The bushing 24 is inserted into the bore 22 from the radially inboard end of the adapter 20. An outer washer 30 fits over the trunnion 18, on the radially outer face of the adapter 20. The assembly is secured by a fastener such as illustrated nut 32.


[0011] This bushing assembly is referred to herein as a "two-piece" configuration.


[0012] As an example, in the existing two-piece configuration, the bushing 24 and the outer washer 30 are made of an aerospace-grade polymer such as high temperature polyimide with additives for strength and friction. The a...