Gas turbine engine aft bearing arrangement

Patent metadata

Field	Value
Publication number	US-10240529-B2
Application number	US-201615274465-A
Country	US
Kind code	B2
Filing date	Sep 23, 2016
Priority date	Jan 31, 2012
Publication date	Mar 26, 2019
Grant date	Mar 26, 2019

Abstract

An example gas turbine engine includes a turbine and first and second spools coaxial with one another. The first spool is arranged within the second spool and extends between forward and aft ends. The aft end extends axially beyond the second spool and supports the turbine. A housing is arranged downstream from the turbine. First and second bearings are mounted to the aft end of the first spool and supported by the housing portion.

First claim

What is claimed is:

1. A bearing hub for a gas turbine engine comprising:
first and second hub walls integrally formed with one another to provide a unitary structure;
a radial to axial translation flange arm extending outward from an apex of the unitary structure;
a translation flange extending outward from said radial to axial translation flange arm;
a spring arm connected to the apex for connecting the bearing hub to a canted annular flange, the spring arm including a plurality of angled flex points.

2. The bearing hub of claim 1 , wherein the radial to axial translation flange arm extends axially aftward from said apex of said unitary structure.

3. The bearing hub of claim 1 , wherein the plurality of angled flex points comprises at least a first flex point, a second flex point, and a third flex point, and wherein a stiffness of each of said first flex point, said second flex point and said third flex point is configured to control an amount of radial vibrations translated to axial vibrations by said bearing hub.

4. The bearing hub of claim 1 , wherein the first and second hub walls are inclined radially inward from an annular apex, and a first and second bearing are respectively supported by the first and second walls opposite the apex.

5. The bearing hub of claim 4 , wherein a focal node of radial vibrations of the bearing hub is the first bearing.

6. The bearing hub of claim 1 , wherein said spring arm is rigidly connected to said apex.

7. A gas turbine engine comprising:
a fan;
a compressor section fluidly connected to the fan, the compressor section comprising a first compressor section and a second compressor section;
a combustor fluidly connected to the compressor section;
a turbine section fluidly connected to the combustor, the turbine section comprising:
a first turbine section coupled to the first compressor section via a shaft;
a second turbine section;

first and second hub walls integrally formed with one another to provide a unitary structure;
a radial to axial translation flange arm extending outward from an annular apex of the unitary structure;
a translation flange extending outward from said radial to axial translation flange arm;
turbine exhaust case arranged downstream from the second turbine section and supporting the annular apex; and
a spring arm connecting the annular apex to a canted annular flange of the turbine exhaust case, the spring arm including a plurality of angled flex points.

8. The gas turbine engine of claim 7 , wherein the radial to axial translation flange arm extends axially aftward from said annular apex of said unitary structure.

9. The gas turbine engine of claim 7 , wherein said translation flange is received in an annular cavity supported by the canted annular flange.

10. The gas turbine engine of claim 9 , wherein said annular cavity includes an axial vibration damper.

11. The gas turbine engine of claim 10 , wherein said axial vibration damper comprises at least a first wire mesh structure disposed between said translation flange and a first wall of said annular cavity.

12. The gas turbine engine of claim 11 , wherein said axial vibration damper comprises at least a second wire mesh structure disposed between said translation flange and a second wall of said annular cavity.

13. The gas turbine engine of claim 10 , wherein said axial vibration damper comprises at least a first seal defining a damping annulus within said annular cavity.

14. The gas turbine engine of claim 13 , further comprising a damping fluid disposed within said damping annulus.

15. The turbine engine of claim 14 , wherein said damping fluid is damping oil.

16. The turbine engine of claim 13 , wherein said axial vibration damper comprises at least a second seal further defining the damping annulus.

17. The turbine engine of claim 13 , wherein said first seal is one of an elastomeric O-ring seal and a piston ring.

18. A method for damping vibrations in a bearing hub comprising the steps of:
converting radial vibrations in said bearing hub to axial vibrations using a spring arm and a radial to axial vibration translation flange, wherein the spring arm includes a plurality of angled flex points;
damping axial vibrations of said radial to axial vibration translation flange using an axial vibration damper.

19. The method of claim 18 , further comprising the step of adjusting a level of vibrational damping by adjusting a stiffness of the spring arm.

Assignees

• United Technologies Corp

Inventors

• Savela Gregory M

Classifications

• F05D2240/50

  Bearings · CPC title

• F02C3/10

  with another turbine driving an output shaft but not driving the compressor · CPC title

• F02C7/20

  Mounting or supporting of plant; Accommodating heat expansion or creep · CPC title

• F02C7/06 Primary

  Arrangements of bearings (bearings F16C); Lubricating ({of turbo machines F01D25/18; of machines or} engines in general F01M) · CPC title

• F05D2260/96

  Preventing, counteracting or reducing vibration or noise · CPC title