Thrust bearing

Patent metadata

Field	Value
Publication number	US-10221885-B2
Application number	US-201615070311-A
Country	US
Kind code	B2
Filing date	Mar 15, 2016
Priority date	Sep 19, 2013
Publication date	Mar 5, 2019
Grant date	Mar 5, 2019

Abstract

A thrust bearing is a thrust bearing disposed facing a thrust collar provided on a rotary shaft and includes a top foil, a back foil and a base plate. The back foil includes a plurality of back foil pieces. The top foil includes a plurality of top foil pieces. In addition, a leading side of the top foil piece in the rotation direction of the rotary shaft is provided with a fixed part fixed to the base plate, an inner circumferential edge side of the top foil piece is provided with an inner circumferential edge-side thin part in which a part is removed from the surface of the top foil piece facing the back foil piece, and the inner circumferential edge-side thin part is formed to be thinner than an outer circumferential edge side of the top foil piece.

First claim

The invention claimed is:

1. A thrust bearing disposed so as to face a thrust collar provided on a rotary shaft, the thrust bearing comprising:
a top foil disposed so as to face the thrust collar;
a back foil disposed so as to face a surface of the top foil opposite to another surface of the top foil facing the thrust collar, and supporting the top foil; and
an annular plate-shaped base plate disposed on a side of the back foil opposite to the top foil, and supporting the back foil;
wherein the back foil includes a plurality of back foil pieces arranged in a circumferential direction of the base plate,
wherein the top foil includes a plurality of top foil pieces disposed on the plurality of back foil pieces,
wherein a leading side of a top foil piece in a rotation direction of the rotary shaft is provided with a fixed part fixed to the base plate,
wherein an inner circumferential edge side of the top foil piece is provided with an inner circumferential edge-side thin part in which a part is removed from a surface of the top foil piece facing a back foil piece, and the inner circumferential edge-side thin part is formed so as to be thinner than an outer circumferential edge side of the top foil piece and extends to a trailing edge on a trailing side of the top foil piece in the rotation direction, and
wherein the back foil piece includes a peak part supporting the top foil piece, and the inner circumferential edge-side thin part overlaps the peak part of the back foil piece.

2. The thrust bearing according to claim 1 ,
wherein a fixed part-side thin part is formed in the fixed part and in a vicinity of the fixed part of the top foil piece on a trailing side of the fixed part in the rotation direction of the rotary shaft and is formed so as to be thinner than the outer circumferential edge side of the top foil piece.

3. The thrust bearing according to claim 2 ,
wherein the top foil piece is formed in an arc sheet shape obtained by dividing an annular sheet in a circumferential direction thereof, and
wherein a borderline between the inner circumferential edge-side thin part and the outer circumferential edge side thereof is formed in an arc shape extending in a circumferential direction of the inner circumferential edge of the top foil piece.

4. The thrust bearing according to claim 3 ,
wherein the fixed part includes a linear fixed edge positioned at a trailing side of the fixed part in the rotation direction of the rotary shaft,
wherein the back foil piece is formed of a wave sheet-shaped bump foil piece in which peak parts and valley parts are alternately formed, and is disposed such that an arrangement direction of the peak parts crosses with the fixed edge, and
wherein a portion of the top foil piece facing a valley part is provided with a valley part-side thin part in which a part is removed from a surface of the top foil piece facing the bump foil piece, and the valley part-side thin part is formed so as to be thinner than a portion of the top foil piece facing a peak part.

5. The thrust bearing according to claim 4 ,
wherein an edge on a trailing side of the bump foil piece in the rotation direction of the rotary shaft is fixed to the base plate.

6. The thrust bearing according to claim 2 ,
wherein the fixed part includes a linear fixed edge positioned at a trailing side of the fixed part in the rotation direction of the rotary shaft,
wherein the back foil piece is formed of a wave sheet-shaped bump foil piece in which peak parts and valley parts are alternately formed, and is disposed such that an arrangement direction of the peak parts crosses with the fixed edge, and
wherein a portion of the top foil piece facing a valley part is provided with a valley part-side thin part in which a part is removed from a surface of the top foil piece facing the bump foil piece, and the valley part-side thin part is formed so as to be thinner than a portion of the top foil piece facing a peak part.

7. The thrust bearing according to claim 6 ,
wherein an edge on a trailing side of the bump foil piece in the rotation direction of the rotary shaft is fixed to the base plate.

8. The thrust bearing according to claim 1 ,
wherein the top foil piece is formed in an arc sheet shape obtained by dividing an annular sheet in a circumferential direction thereof, and
wherein a borderline between the inner circumferential edge-side thin part and the outer circumferential edge side thereof is formed in an arc shape extending in a circumferential direction of the inner circumferential edge of the top foil piece.

9. The thrust bearing according to claim 8 ,
wherein the fixed part includes a linear fixed edge positioned at a trailing side of the fixed part in the rotation direction of the rotary shaft,
wherein the back foil piece is formed of a wave sheet-shaped bump foil piece in which peak parts and valley parts are alternately formed, and is disposed such that an arrangement direction of the peak parts crosses with the fixed edge, and
wherein a portion of the top foil piece facing a valley part is provided with a valley part-side thin part in which a part is removed from a surface of the top foil piece facing the bump foil piece, and the valley part-side thin part is formed so as to be thinner than a portion of the top foil piece facing a peak part.

10. The thrust bearing according to claim 9 ,
wherein an edge on a trailing side of the bump foil piece in the rotation direction of the rotary shaft is fixed to the base plate.

11. The thrust bearing according to claim 1 ,
wherein the fixed part includes a linear fixed edge positioned at a trailing side of the fixed part in the rotation direction of the rotary shaft,
wherein the back foil piece is formed of a wave sheet-shaped bump foil piece in which peak parts and valley parts are alternately formed, and is disposed such that an arrangement direction of the peak parts crosses with the fixed edge, and
wherein a portion of the top foil piece facing a valley part is provided with a valley part-side thin part in which a part is removed from a surface of the top foil piece facing the bump foil piece, and the valley part-side thin part is formed so as to be thinner than a portion of the top foil piece facing a peak part.

12. The thrust bearing according to claim 11 ,
wherein an edge on a trailing side of the bump foil piece in the rotation direction of the rotary shaft is fixed to the base plate.

13. The thrust bearing according to claim 1 ,
wherein an extension of a borderline between the inner circumferential edge-side thin part and the outer circumferential edge side of the top foil piece crosses the fixed part in plan view.

14. A thrust bearing, comprising:
an annular base plate;
a back foil piece disposed on the base plate; and
a top foil piece disposed on the back foil piece;
wherein a first side of the top foil piece in a circumferential direction of the base plate is fixed to the base plate,
wherein the top foil piece includes a stepped part such that a radially inner side of the stepped part of the top foil piece is provided with a thin part thinner than a radially outer side of the stepped part of the top foil piece,
wherein the thin part extends to a circumferentially facing edge on a second side opposite to the first side of the top foil piece in the circumferential direction, and
wherein the back foil piece includes a peak part supporting the top foil piece, and the thin part overlaps the peak part of the back foil piece.

15. The thrust bearing according to claim 14 ,
wherein an extension of a borderline in plan view between the

Assignees

• Ihi Corp

Inventors

• Omori Naomichi

Classifications

• F16C2240/46

  Gap sizes or clearances · CPC title

• F16C17/042 Primary

  with flexible leaves to create hydrodynamic wedge, e.g. axial foil bearings · CPC title

• F16C2360/00

  Engines or pumps · CPC title