Self-lubricating bushings

Patent metadata

Field	Value
Publication number	US-9835053-B2
Application number	US-201514623320-A
Country	US
Kind code	B2
Filing date	Feb 16, 2015
Priority date	Feb 21, 2014
Publication date	Dec 5, 2017
Grant date	Dec 5, 2017

Abstract

A bushing includes a cylindrical bushing body with a lubricant aperture and a dry lubrication source. The bushing defines a main bushing bore therethrough along a longitudinal axis. The lubricant aperture is defined in the bushing body along an angle relative to the longitudinal axis. The dry lubrication source is disposed in the lubricant aperture. A variable vane system includes a cylindrical case, a plurality of vanes projecting radially inward from the case, and a plurality of bushings. Each vane includes a respective vane stem operatively connecting an end of each vane to the case. Each bushing is disposed on one of the respective vane stems between the vane stem and the case. The respective vane stem is disposed within the main bushing bore and each bushing is slidingly engaged with the case.

First claim

What is claimed is:

1. A self-lubricating bushing for variable vanes of a gas turbine engine, comprising:
a cylindrical bushing body defining a main bushing bore therethrough along a longitudinal axis, wherein the bushing body includes a lubricant aperture extending radially from the main bushing bore, and the lubricant aperture extends from an outer diameter surface of the bushing body and into the main bushing bore;
a dry lubrication source disposed in the lubricant aperture, wherein the bushing body includes at least one additional lubricant aperture extending from the outer diameter surface of the bushing body and into the main bushing bore, wherein each additional lubricant aperture also includes a dry lubrication source disposed therein; and
a connecting bore located within the cylindrical bushing body and spaced from the outer diameter surface of the bushing body and an inner diameter surface of the bushing body, the connecting bore extending from an end surface of the bushing body in a longitudinal direction with respect to the longitudinal axis connecting together the lubricant aperture and the at least one additional lubricant aperture.

2. A bushing as recited in claim 1 , wherein the lubricant aperture extends radially inward from the outer diameter surface along an aperture axis, wherein the aperture axis is normal to the outer diameter surface of the bushing body.

3. A bushing as recited in claim 1 , wherein the lubricant aperture is cylindrical.

4. A bushing as recited in claim 1 , wherein the lubricant aperture and the at least one additional lubricant aperture are a plurality of apertures are arranged in a geometric array on the bushing body.

5. A bushing as recited in claim 4 , wherein the geometric array is a staggered geometric array.

6. A bushing as recited in claim 1 , wherein the bushing body comprises a metallic material.

7. A bushing as recited in claim 1 , wherein the dry lubrication source includes a dry lubricant material selected from the group consisting of polymer and graphite.

8. A variable vane system, comprising:
a cylindrical case;
a plurality of vanes projecting radially inward from the case, wherein each vane includes a respective vane stem operatively connecting an end of each vane to the case; and
a plurality of bushings, each bushing including:
a cylindrical bushing body defining a main bushing bore therethrough along a longitudinal axis, wherein the bushing body includes a lubricant aperture extending radially from the main bushing bore, and the lubricant aperture extends from an outer diameter surface of the bushing body and into the main bushing bore; and
a dry lubrication source disposed in the lubricant aperture, wherein the bushing body includes at least one additional lubricant aperture extending from the outer diameter surface of the bushing body and into the main bushing bore, wherein each additional lubricant aperture also includes a dry lubrication source disposed therein; and
a connecting bore located within the cylindrical bushing body and spaced from the outer diameter surface of the bushing body and an inner diameter surface of the bushing body, the connecting bore extending from an end surface of the bushing body in a longitudinal direction with respect to the longitudinal axis connecting together the lubricant aperture and the at least one additional lubricant aperture, wherein one of the plurality of bushings is disposed on each one of the respective vane stems between the vane stem and the case, wherein the respective vane stem is disposed within the respective main bushing bore and wherein each bushing is slidingly engaged with the case.

9. A system as recited in claim 8 , wherein the inner diameter surface of each bushing is press-fit around one of the respective vane stems.

10. A system as recited in claim 8 , further comprising a plurality of secondary bushings, wherein the plurality of bushings are a plurality of primary bushings, wherein each secondary bushing has an outer diameter surface operatively connected to the case and an inner diameter surface slidingly engaged with the outer diameter surface of one of the primary bushings.

11. A system as recited in claim 10 , wherein the outer diameter surface of each secondary bushing is press-fit within a respective one of a plurality of cavities within the case.

12. A system as recited in claim 8 , wherein the lubricant aperture is disposed on the outer diameter surface of the bushing body.

13. A system as recited in claim 12 , wherein the lubricant aperture extends radially inward from the outer diameter surface along an aperture axis, wherein the aperture axis is normal to the outer diameter surface of the bushing body.

14. A system as recited in claim 8 , wherein the lubricant aperture is cylindrical.

Assignees

• United Technologies Corp

Inventors

• Do Logan H

Classifications

• F01D9/041

  using blades (F01D5/148 takes precedence) · CPC title

• F05D2240/50

  Bearings · CPC title

• F01D25/16

  Arrangement of bearings; Supporting or mounting bearings in casings (bearings per se F16C) · CPC title

• F01D25/18 Primary

  Lubricating arrangements (of machines or engines in general F01M) · CPC title

• F05D2220/32

  in gas turbines · CPC title