Yoke and bearing fitting assembly for rotors

• US 8,360,727 B2
• Filed: 01/19/2009
• Issued: 01/29/2013
• Est. Priority Date: 01/19/2009
• Status: Active Grant

• Current Assignee: Textron Innovations Incorporated (Textron Inc)
• Original Assignee: Textron Innovations Incorporated (Textron Inc)
• Inventors: Stamps, Frank B., Tisdale, Patrick R., Campbell, Thomas C., Rauber, Richard E., Braswell, James L. Jr.
• Primary Examiner(s): VERDIER, CHRISTOPHER M
• Application Number:
  US13/144,510
• Publication Number:
  US 20110274550A1
• Time in Patent Office: 1,471 Days
• Field of Search: 416/106, 416/107, 416/134.A, 416/138, 416/140, 416/141, 416/244.R
• US Class Current: 416/134.A
• CPC Class Codes: B64C 27/32 Rotors
• CPC Class Codes: B64C 27/33 having flexing arms

Abstract

A yoke and bearing fitting assembly for a multi-blade aircraft rotor is disclosed. The assembly has a yoke having arms extending generally radially from a central portion of the yoke, the arms each having opposing surfaces. An aperture is formed in each arm and extends between the surfaces. A bearing fitting has a body configured for insertion into the aperture of the yoke and has two rims protruding from a periphery of the body, the body also having a bearing mount adapted for mounting a pitch change bearing assembly to the yoke. Each rim abuts one of the surfaces of the associated yoke arm when the bearing fitting is installed within the aperture, so as to create clamping forces between the rims and the arm and the arm. The bearing fitting transmits forces from the pitch bearing assembly into the yoke.

Claims

1. A yoke and bearing fitting assembly for a multi-blade aircraft rotor, comprising:

a yoke having arms extending generally radially from a central portion of the yoke, the arms each having an upper surface and a lower surface an aperture being formed in each arm and extending between the upper surface and the lower surface, the aperture having an inboard and an outboard end; and

a bearing fitting comprising a body configured for insertion into the aperture of the yoke, such that the bearing fitting extends within the aperture from the inboard end to the outboard end, the bearing fitting having two rims protruding from a periphery of the body, the rim at the inboard end being discontinuous from the rim at the outboard end of the aperture, the bearing fitting also having a bearing mount adapted for mounting a pitch-change bearing assembly to the yoke;

wherein each rim abuts one of the surfaces of the associated yoke arm when the bearing fitting is installed within the aperture, so as to create clamping forces between the rims and the arm; and

wherein the bearing fitting is adapted for transmitting forces from the pitch bearing assembly into the yoke.

2. The assembly according to claim 1, wherein the bearing fitting is formed as two pieces.

3. The assembly according to claim 1, wherein the bearing fitting is formed as two halves.

4. The assembly according to claim 1, wherein the bearing fitting is formed as two halves, a rim being located on each half.

5. The assembly according to claim 1, further comprising:

an elastomeric buffer located between each rim and the adjacent surface of the yoke.

6. The assembly according to claim 1, further comprising:

a Teflon buffer located between each rim and the adjacent surface of the yoke.

7. A yoke and bearing fitting assembly for a multi-blade aircraft rotor, comprising:

a yoke having arms extending generally radially from a central portion of the yoke, the arms each having an upper surface and a lower surface an aperture being formed in each arm and extending between the upper surface and the lower surface, the aperture having an inboard and an outboard end; and

a bearing fitting comprising a body configured for insertion into the aperture of the yoke, such that the bearing fitting extends within the aperture from the inboard end to the outboard end, the bearing fitting having two rims protruding from a periphery of the body, the bearing fitting being formed in at least two pieces, the rim at the inboard end being discontinuous from the rim at the outboard end of the aperture, the bearing fitting having a bearing mount adapted for mounting a pitch-change bearing assembly to the yoke;

wherein each rim abuts one of the surfaces of the associated yoke arm when the bearing fitting is installed within the aperture, so as to create clamping forces between the rims and the arm; and

wherein the bearing fitting is adapted for transmitting forces from the pitch bearing assembly into the yoke.

8. The assembly according to claim 7, wherein the bearing fitting is formed as two halves.

9. The assembly according to claim 7, wherein the bearing fitting is formed as two halves, a rim being located on each half.

10. The assembly according to claim 7, further comprising:

an elastomeric buffer located between each rim and the adjacent surface of the yoke.

11. The assembly according to claim 7, further comprising:

a Teflon buffer located between each rim and the adjacent surface of the yoke.

12. A bearing fitting for installing a pitch-change bearing in a rotor yoke, the fitting comprising:

a body adapted for insertion into an aperture in an arm of the rotor yoke, the body extending within the aperture from an inboard end of the aperture to an outboard end of the aperture;

two rims protruding from a periphery of the body, each rim contacting an opposing surface of the rotor yoke, the rim adjacent the inboard end being distinct from the rim along the outboard end of the aperture;

a bearing mount adapted for locating a pitch-change bearing assembly within the fitting;

wherein each rim is adapted to abut one of opposing surfaces of the yoke arm when the bearing fitting is installed within the aperture, so as to create clamping forces between the rims and the arm; and

wherein the bearing fitting is adapted for transmitting forces from the pitch bearing assembly into the yoke.

13. The bearing fitting according to claim 12, wherein the bearing fitting is formed as two pieces.

14. The bearing fitting according to claim 12, wherein the bearing fitting is formed as two halves.

15. The bearing fitting according to claim 12, wherein the bearing fitting is formed as two halves, a rim being located on each half.