Disc spring centering device for squeeze film dampers

1. A damper film bearing assembly for supporting a rotatable shaft, said damper film bearing assembly comprising:

a bearing housing having a longitudinal opening passing therethrough for receiving the rotatable shaft, said bearing housing also having at least one radial recess formed in an outer surface thereof, the recess having a floor;

at least one support piston slideably disposed within the recess in said bearing housing, said support piston slideable within the recess radially toward and away from a central longitudinal axis of the rotatable shaft; and

at least one resilient element disposed within the recess in said bearing housing between the floor of the recess and said support piston, said resilient element biasing said support piston away from the axis of the rotatable shaft.

2. The damper film bearing of claim 1 wherein said at least one resilient element comprises at least one disc spring.

3. The damper film bearing assembly of claim 1 wherein said at least one resilient element comprises a plurality of resilient elements.

4. The damper film bearing of claim 3 wherein said plurality of resilient elements comprises a plurality of disc springs.

5. The damper film bearing of claim 4 wherein at least some of said plurality of disc springs are arranged in parallel.

6. The damper film bearing of claim 4 wherein at least some of said plurality of disc springs are arranged in series.

7. The damper film bearing of claim 1 wherein said at least one radial recess formed in the outer surface of said bearing housing comprises a plurality of radial recesses formed in the outer surface of said bearing housing, and wherein said at least one support piston comprises a plurality of support pistons.

8. The damper film bearing of claim 7 wherein the plurality of radial recesses are radially spaced around a circumference of said bearing housing.

9. The damper film bearing of claim 7 wherein the plurality of radial recesses are spaced longitudinally along said bearing housing.

10. The damper film bearing of claim 1 further comprising a preloading bolt causing said support piston to be moved toward the axis of the rotatable shaft and against the bias of said resilient element and held in that position.

11. The damper film bearing of claim 10 wherein said preloading bolt comprises a threaded bolt cooperating with a threaded opening in the floor of the recess of said bearing housing.

12. The damper film bearing of claim 1 further comprising a backing washer disposed between the floor of the recess of said bearing housing and said resilient element.

13. A damper film bearing assembly for supporting a rotatable shaft, said damper film bearing assembly comprising:

a bearing housing having a longitudinal opening passing therethrough for receiving the rotatable shaft;

a bearing case having a longitudinal opening passing therethrough for receiving said bearing housing, an outer surface of said bearing housing and an inner surface of said bearing case defining a space therebetween adapted to receive a damper oil therein;

wherein at least one of the outer surface of said bearing housing and the inner surface of said bearing case have at least one radial recess formed therein, the recess having a floor;

at least one support piston slideably disposed within the recess, said support piston slideable within the recess radially toward and away from the space defined between the outer surface of said bearing housing and the inner surface of said bearing case; and

at least one resilient element disposed within the recess between the floor of the recess and said support piston, said resilient element biasing said support piston toward the space defined between the outer surface of said bearing housing and the inner surface of said bearing case.

14. The damper film bearing assembly of claim 13 wherein said bearing case comprises a generally continuous wall without radial holes passing completely therethrough.

15. The damper film bearing of claim 13 wherein said at least one resilient element comprises at least one disc spring.

16. The damper film bearing assembly of claim 13 wherein said at least one resilient element comprises a plurality of resilient elements.

17. The damper film bearing of claim 16 wherein said plurality of resilient elements comprises a plurality of disc springs.

18. The damper film bearing of claim 17 wherein at least some of said plurality of disc springs are arranged in parallel.

19. The damper film bearing of claim 17 wherein at least some of said plurality of disc springs are arranged in series.

20. The damper film bearing of claim 13 wherein said at least one radial recess comprises a plurality of radial recesses, and wherein said at least one support piston comprises a plurality of support pistons.

21. The damper film bearing of claim 20 wherein the plurality of radial recesses are radially spaced.

22. The damper film bearing of claim 20 wherein the plurality of radial recesses are spaced longitudinally.

23. The damper film bearing of claim 13 further comprising a preloading bolt causing said support piston to be moved away from the space defined between the outer surface of said bearing housing and the inner surface of said bearing case and against the bias of said resilient element and held in that position.

24. The damper film bearing of claim 23 wherein said preloading bolt comprises a threaded bolt cooperating with a threaded opening in the floor of the recess.

25. The damper film bearing of claim 13 further comprising a backing washer disposed between the floor of the recess and said resilient element.