Turbo engine comprising a damping fluid film for damping a guide bearing of a shaft of the turbo engine and method of adjusting the thickness of such a damping fluid film

Patent metadata

Field	Value
Publication number	US-9631493-B2
Application number	US-201214240152-A
Country	US
Kind code	B2
Filing date	Sep 4, 2012
Priority date	Sep 5, 2011
Publication date	Apr 25, 2017
Grant date	Apr 25, 2017

Abstract

A turbine engine including a casing, a turbine engine shaft extending axially, a guide bearing for guiding the turbine engine shaft in the casing, the guide bearing including an inner circumferential ring rigidly connected to the turbine engine shaft, an outer circumferential ring fitted in a housing of the casing, and gripping rolling members, and a damping cavity configured to receive a damping fluid to form a damping fluid film for damping the guide bearing, the cavity being delimited radially between an outer surface of the outer ring and an inner surface of the housing. The outer surface of the outer ring and the inner surface of the housing are conical surfaces.

First claim

The invention claimed is:

1. A turbine engine comprising:
a casing including an annular cavity in which is fitted a circumferential housing ring with an outer surface in contact with an inner surface of the annular cavity of the casing;
a turbine engine shaft extending axially;
a guide bearing to guide the turbine engine shaft in the casing, the guide bearing including an inner circumferential ring rigidly connected to the turbine engine shaft and an outer circumferential ring fitted in the housing ring and gripping rolling members;
a damping cavity, configured to receive a damping fluid that flows from a radially outer surface of the housing ring to a radially inner surface of the housing ring to form a damping fluid film to dampen the guide bearing, the damping cavity being delimited radially between an outer surface of the outer ring and the inner surface of the housing ring, the outer surface of the outer ring and the inner surface of the housing ring being conical surfaces; and
a mechanism to adjust an axial position of the housing ring relative to the casing, the mechanism including a shim fitted removably to the housing ring.

2. A turbine engine according to claim 1 , wherein the outer surface of the outer ring and the inner surface of the housing ring are conical surfaces of revolution with substantially a same cone angle.

3. A turbine engine according to claim 2 , wherein the cone angle is substantially equal to 2°.

4. A turbine engine according to claim 1 , wherein the shim and the housing ring are rigidly connected to the casing by at least one retaining bolt.

5. A turbine engine according to claim 1 , wherein the housing ring includes a radial flange, formed at a longitudinal extremity of a body of the housing ring, to which the mechanism is fixed.

6. A turbine engine according to claim 1 , wherein a longitudinal body of the housing ring includes a plurality of radial distribution orifices.

7. A turbine engine according to claim 1 , wherein the damping cavity is configured to receive the damping fluid that flows from the radially outer surface of the housing ring to the radially inner surface of the housing ring through at least one distribution orifice in the housing ring.

8. A turbine engine according to claim 7 , wherein the radially inner surface of the housing ring includes an annular distribution groove into which the at least one distribution orifice in the housing ring opens.

9. A turbine engine according to claim 7 , wherein the at least one distribution orifice in the housing ring is axially positioned between an upstream seal and a downstream seal that seal the damping cavity.

10. A turbine engine according to claim 1 , wherein the inner surface of the annular cavity of the casing includes an annular groove that is supplied with the damping fluid.

11. A method for adjusting a thickness of a damping fluid film to dampen a guide bearing of a turbine engine shaft in a turbine engine casing including an annular cavity in which there is fitted a circumferential housing ring including a radially outer surface in contact with an inner surface of the annular cavity of the casing, the guide bearing including an inner circumferential ring rigidly connected to the turbine engine shaft and an outer circumferential ring fitted in the housing ring and gripping rolling members, a damping cavity, configured to receive a damping fluid to form a damping fluid film to dampen the guide bearing, the cavity being delimited radially between an outer conical surface of the outer ring and an inner conical surface of the housing ring, the method comprising:
positioning a shim between the housing ring and the casing to axially displace the outer ring relative to the housing ring to modify a radial thickness of the damping fluid film in the damping cavity, and the damping fluid to form the damping fluid film flows from the radially outer surface of the housing ring to the inner conical surface of the housing ring.

12. A turbine engine comprising:
a casing including an annular cavity in which is fitted a circumferential housing ring with an outer surface in contact with an inner surface of the annular cavity of the casing;
a turbine engine shaft extending axially;
a guide bearing to guide the turbine engine shaft in the casing, the guide bearing including an inner circumferential ring rigidly connected to the turbine engine shaft and an outer circumferential ring fitted in the housing ring and gripping rolling members;
a damping cavity, configured to receive a damping fluid to form a damping fluid film to dampen the guide bearing, the damping cavity being delimited radially between an outer surface of the outer ring and an inner surface of the housing ring, the outer surface of the outer ring and the inner surface of the housing ring being conical surfaces; and
a mechanism to adjust an axial position of the housing ring relative to the casing, the mechanism including a shim fitted removably to the housing ring, wherein
a longitudinal body of the housing ring includes a plurality of radial distribution orifices.

13. A turbine engine according to claim 12 , wherein the outer surface of the outer ring and the inner surface of the housing ring are conical surfaces of revolution with substantially a same cone angle.

14. A turbine engine according to claim 13 , wherein the cone angle is substantially equal to 2°.

15. A turbine engine according to claim 12 , wherein the shim and the housing ring are rigidly connected to the casing by at least one retaining bolt.

16. A turbine engine according to claim 12 , wherein the housing ring includes a radial flange, formed at a longitudinal extremity of a body of the housing ring, to which the mechanism is fixed.

17. A turbine engine according to claim 12 , wherein the damping cavity is configured to receive the damping fluid that flows from the outer surface of the housing ring to the inner surface of the housing ring through the radial distribution orifices.

18. A turbine engine according to claim 17 , wherein the inner surface of the housing ring includes an annular distribution groove into which the radial distribution orifices open.

19. A turbine engine according to claim 17 , wherein the radial distribution orifices are axially positioned between an upstream seal and a downstream seal that seal the damping cavity.

20. A turbine engine according to claim 12 , wherein the inner surface of the annular cavity of the casing includes an annular groove that is supplied with the damping fluid.

Assignees

• Morreale Serge Rene
• Vial Albert
• Chevillot Fabrice
• Snecma

Inventors

• Morreale Serge Rene
• Vial Albert
• Chevillot Fabrice

Classifications

• F16C27/045

  with a fluid film, e.g. squeeze film damping · CPC title

• F16F15/0237

  involving squeeze-film damping · CPC title

• F01D1/04 Primary

  traversed by the working-fluid substantially axially · CPC title

• F05D2250/232

  conical · CPC title

• F02C7/06

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