Imbalance damping devices for gas turbine engine fan shaft bearings

Patent metadata

Field	Value
Publication number	US-11021995-B2
Application number	US-201816055704-A
Country	US
Kind code	B2
Filing date	Aug 6, 2018
Priority date	Aug 6, 2018
Publication date	Jun 1, 2021
Grant date	Jun 1, 2021

Abstract

A gas turbine engine includes a fan rotating with a fan shaft, a compressor and a turbine section. The turbine section includes a fan drive rotor driving the fan through the fan shaft. At least one bearing is between an inner static case and the fan shaft. The inner static case is cantilever mounted to static structure, and has a forward end spaced in a forward direction toward the fan rotor from a cantilever mount. A damping assembly is associated with the inner static case.

First claim

The invention claimed is:

1. A gas turbine engine comprising:
a fan rotating with a fan shaft, a compressor and a turbine section, said turbine section including a fan drive rotor driving said fan through said fan shaft;
at least one bearing between an inner static case and said fan shaft, and said inner static case being cantilever mounted to static structure, and having a forward end spaced in a forward direction toward said fan from a cantilever mount, and there being a damping assembly associated with said inner static case;
said damping assembly includes a particle damper positioned between said forward end of said inner static case and a bearing support structure supporting said at least one bearing, with said particle damper being positioned radially intermediate said inner static case and said bearing support structure;
said particle damper includes a plurality of elements within a chamber, and air filling at least some percent of said chamber;
wherein said particle damper includes a plurality of radially extending separating members separating said particle damper into a plurality of circumferentially spaced chambers each receiving said particles; and
wherein said damping assembly further includes an elastic damping member positioned adjacent a rear end of said inner static case and said cantilever mount.

2. The gas turbine engine as set forth in claim 1 , wherein said air fills between 1% and 40% of a volume of said chamber.

3. The gas turbine engine as set forth in claim 2 , wherein said particles in said particle damper are at least one of metallic particles and a powder.

4. The gas turbine engine as set forth in claim 1 , wherein said elastic damping member is positioned radially inward of said rear end of said inner static case.

5. The gas turbine engine as set forth in claim 1 , wherein said elastic damping member includes a viscoelastic material.

6. The gas turbine engine as set forth in claim 5 , wherein a constraining layer is positioned radially about said viscoelastic material.

7. The gas turbine engine as set forth in claim 1 , wherein a second bearing is positioned radially inwardly of said rear end of said inner static case and axially adjacent said cantilever mount, such that said elastic damping member is adjacent to said second bearing.

8. The gas turbine engine as set forth in claim 7 , wherein said second bearing is a thrust bearing.

9. The gas turbine engine as set forth in claim 8 , wherein said elastic damping member includes a viscoelastic material.

10. The gas turbine engine as set forth in claim 9 , wherein a constraining layer is positioned radially about said viscoelastic material.

11. A gas turbine engine comprising:
a fan rotating with a fan shaft, a compressor and a turbine section, said turbine section including a fan drive rotor driving said fan through said fan shaft;
at least one bearing between an inner static case and said fan shaft, and said inner static case being cantilever mounted to static structure, and having a forward end spaced in a forward direction toward said fan from a cantilever mount, and there being a damping assembly associated with said inner static case;
wherein said damping assembly includes a particle damper is positioned between said forward end of said inner static case and a bearing support structure supporting said at least one bearing, with said particle damper being positioned radially intermediate said inner static case and said bearing support structure;
wherein said particle damper includes a plurality of elements within a chamber, and air filling at least some percent of said chamber;
wherein said particles in said particle damper are at least one of metallic particles and a powder;
wherein said particle damper includes a plurality of radially extending separating members separating said particle damper into a plurality of circumferentially spaced chambers each receiving said particles; and
wherein said damping assembly further includes an elastic damping member positioned adjacent a rear end of said inner static case and said cantilever mount.

12. The gas turbine engine as set forth in claim 11 , wherein a second bearing is positioned radially inwardly of said rear end of said inner static case and axially adjacent said cantilever mount, such that said elastic damping member is adjacent to said second bearing.

13. The gas turbine engine as set forth in claim 12 , wherein said second bearing is a thrust bearing.

14. The gas turbine engine as set forth in claim 13 , wherein said elastic damping member includes a viscoelastic material.

15. The gas turbine engine as set forth in claim 14 , wherein a constraining layer is positioned radially about said viscoelastic material.

16. The gas turbine engine as set forth in claim 15 , wherein said elastic damping member is positioned radially inward of said rear end of said inner static case.

17. A gas turbine engine comprising:
a fan rotating with a fan shaft, a compressor and a turbine section, said turbine section including a fan drive rotor driving said fan through said fan shaft;
at least one bearing between an inner static case and said fan shaft, and said inner static case being cantilever mounted to static structure, and having a forward end spaced in a forward direction toward said fan from a cantilever mount, and there being a damping assembly associated with said inner static case;
wherein said damping assembly includes a particle damper positioned between said forward end of said inner static case and a bearing support structure supporting said at least one bearing, with said particle damper being positioned radially intermediate said inner static case and said bearing support structure;
wherein said particle damper includes a plurality of elements within a chamber, and air filling at least some percent of said chamber; and
wherein said damping assembly further includes an elastic damping member positioned adjacent a rear end of said inner static case and said cantilever mount.

Assignees

• United Technologies Corp
• Raytheon Tech Corp

Inventors

• Morris Robert J

Classifications

• F16F15/36

  operating automatically {, i.e. where, for a given amount of imbalance, there is movement of masses until balance is achieved (damping vibrations of washing machines by displacing, supplying or ejecting a material, e.g. liquid, into or from counterbalancing pockets D06F37/245)} · CPC title

• F16C2360/23

  Gas turbine engines · CPC title

• F05D2260/96

  Preventing, counteracting or reducing vibration or noise · CPC title

• F16F7/01

  using friction between loose particles, e.g. sand · CPC title

• F05D2240/50

  Bearings · CPC title