Foil bearing

• US 6,953,283 B2
• Filed: 08/21/2003
• Issued: 10/11/2005
• Est. Priority Date: 08/28/2002
• Status: Expired due to Fees

• Current Assignee: Honda Giken Kogyo Kabushiki Kaisha (Honda Motor Company)
• Original Assignee: Honda Giken Kogyo Kabushiki Kaisha (Honda Motor Company)
• Inventors: Matsunaga, Minoru
• Primary Examiner(s): Footland, Lenard A.
• Application Number:
  US10/644,724
• Publication Number:
  US 20040042691A1
• Time in Patent Office: 782 Days
• Field of Search: 384/103, 384/105, 384/104, 384/106
• US Class Current: 384/103
• CPC Class Codes: F16C 17/024 with flexible leaves to create hydrodynamic wedge, e.g. radial foil bearings
• CPC Class Codes: F16C 17/042 with flexible leaves to create hydrodynamic wedge, e.g. axial foil bearings
• CPC Class Codes: F16C 2360/23 Gas turbine engines in general F02C
• CPC Class Codes: F16C 25/02 Sliding-contact bearings
• CPC Class Codes: F16C 43/02 Assembling sliding-contact bearings

Abstract

In a foil bearing (23) having a plurality of foils (26) disposed in a gap between a rotating member (12) and a stationary mount member (25), a moveable member (27) is disposed on a side of the stationary member opposite to the rotating member so as to be rotatable with respect to the stationary mount member, abutting members (30) extend from the moveable member toward the associated foils through respective through-holes formed in the stationary mount member, and a surface of the moveable member with which one end of each abutting member is in contact is provided with a cam surface. In such a structure, by rotating the moveable member and thus changing the length of the abutting members projecting out from the surface of the stationary mount member, it is possible to vary the range of movement of the foils and practically vary the stiffness of the same.

Claims

1. A foil bearing for supporting a rotating member that rotates about an axis, comprising:

a stationary mount member spaced from the rotating member so that a gap is defined between the stationary mount member and the rotating member, the stationary mount member having a first surface facing the rotating member and a second surface opposite to the first surface;

a moveable member disposed on a side of the stationary mount member opposite to the rotating member so as to be rotatable about the axis, the moveable member having a first surface facing the second surface of the stationary mount member;

a first foil disposed in the gap between the rotating member and the stationary mount member to support the rotating member via a fluid film when the rotating member rotates, the first foil having a portion extending in a substantially circumferential direction; and

an abutting member extending from the moveable member toward the first foil through a through-hole formed in the stationary mount member, the abutting member having one end in contact with the first surface of the moveable member and other end facing the circumferentially extending portion of the first foil,

wherein a cam surface is formed on a part of the first surface of the moveable member with which the one end of the abutting member is in contact so that rotation of the moveable member around the axis can vary a length of the other end portion of the abutting member projecting out from the first surface of the stationary mount member toward the circumferentially extending portion of the first foil.

2. A foil bearing according to claim 1, comprising a plurality of the first foils arranged in the circumferential direction of the rotating member, and at least one of the plurality of first foils is allotted with the abutting member.

3. A foil bearing according to claim 2, each of the plurality of first foils is allotted with the abutting member.

4. A foil bearing according to claim 1, comprising a plurality of the abutting members having varying lengths.

5. A foil bearing according to claim 1, comprising a plurality of the abutting members wherein a plurality of the cam surfaces are provided on the first surface of the moveable member corresponding to the plurality of abutting members, the plurality of first cam surfaces having varying levels.

6. A foil bearing according to claim 2, wherein spaces between adjacent ones of the plurality of first foils are varied.

7. A foil bearing according to claim 1, wherein the rotating member comprises a shaft having a substantially cylindrical portion, and the stationary mount member surrounds the shaft so that the gap is formed as an annular gap defined between a cylindrical surface of the cylindrical portion of the shaft and the stationary mount member.

8. A foil bearing according to claim 7, wherein the shaft consists of a rotor shaft of a gas turbine engine, and the foil bearing constitutes a journal bearing for the rotor shaft of the gas turbine engine.

9. A foil bearing according to claim 7, comprising a plurality of the first foils arranged in the circumferential direction of the shaft, and the foil bearing further comprises a second foil disposed between the shaft and the plurality of first foils and extending in the circumferential direction to have a substantially cylindrical shape.

10. A foil bearing according to claim 1, wherein the rotating member comprises a disk-shaped member and the gap is defined between the stationary mount member and a planar surface of the disk-shaped member.

11. A foil bearing according to claim 10, wherein the disk-shaped member is provided as a unitary portion of a rotor shaft of a gas turbine engine, and the foil bearing constitutes a thrust bearing of the rotor shaft of the gas turbine engine.

12. A foil bearing for supporting a rotating member that rotates about an axis, comprising:

a stationary mount member surrounding the rotating member so that a gap is defined between the stationary mount member and the rotating member, the stationary mount member having an inner circumferential surface facing the rotating member and an outer circumferential surface opposite to the inner circumferential surface; and

a top foil disposed in the gap between the rotating member and the stationary mount member to support the rotating member via a fluid film when the rotating member rotates, the top foil consisting of a member extending in a circumferential direction to have a substantially cylindrical shape,

wherein one end of the top foil is secured to the stationary mount member while the other end of the top foil extends in a radial direction through a slot formed in the stationary mount member at a position near the one end of the top foil to project out from the outer circumferential surface of the stationary mount member,

and wherein the foil bearing further comprises an abutting member which is moveably attached to the stationary member so as to abut a side of the radially extending portion of the other end of the top foil facing away from the one end of the top foil whereby stiffness of the top foil can be practically adjusted by varying a position at which the abutting member abuts the radially extending portion of the top foil.