Composite Rotor System Using Two Race Track Style Cantilevered Yokes

• US 20140271222A1
• Filed: 03/13/2013
• Published: 09/18/2014
• Est. Priority Date: 03/13/2013
• Status: Active Grant

• Current Assignee: Textron Innovations Incorporated (Textron Inc)
• Original Assignee: Bell Helicopter Textron Incorporated (Textron Inc)
• Inventors: Maresh, Andrew, Stamps, Frank Bradley, Tisdale, Patrick Ryan, Haldeman, Andrew, Sutton, Drew, Wardlaw, Robert
• Granted Patent: US 9,505,490 B2
• Time in Patent Office: Days
• US Class Current: 416/244.R
• CPC Class Codes: B64C 11/02 Hub construction
• CPC Class Codes: B64C 11/12 flexible
• CPC Class Codes: B64C 27/33 having flexing arms
• CPC Class Codes: B64C 27/35 having elastomeric joints
• CPC Class Codes: B64C 27/48 Root attachment to rotor head

Abstract

A hub system comprises at least one yoke, at least one shear bearing, and at least one mast adapter. The at least one mast adapter is configured to support the at least one yoke and the at least one shear bearing, and the at least one yoke has a flapping hinge that is non-coincident with a flapping hinge of the at least one shear bearing. Another hub system comprises a stacked yoke and a mast adapter. The mast adapter is configured to transfer rotation from a rotor mast to the hub system to rotate the hub system about a central axis of rotation. The mast adapter is further configured to support the stacked yoke such that each yoke in the stacked yoke is configured to accommodate at least some amount of rotation about an axis that is perpendicular to or about perpendicular to the central axis of rotation.

Claims

1. A hub system comprising:

at least one yoke;

at least one shear bearing;

at least one mast adapter configured to support the at least one yoke and the at least one shear bearing, and

wherein the at least one yoke has a flapping hinge that is non-coincident with a flapping hinge of the at least one shear bearing.

2. The hub system of claim 1, wherein the at least one yoke flapping hinge is located inboard of the at least one shear bearing flapping hinge.

3. The hub system of claim 1, wherein the at least one yoke comprises a built in pre-cone angle and a flexure section, and wherein the at least one mast adapter is configured to support the at least one yoke without extending into the flexure section.

4. The hub system of claim 1, wherein the at least one yoke comprises mast sections, outboard sections, and flexure sections extending between the mast sections and the outboard sections, and wherein the at least one mast adapter is configured to support the at least one yoke through at least one aperture in a center or about the center of each of the mast sections.

5. The hub system of claim 1, wherein the at least one mast adapter comprises a number of arms, and wherein each arm comprises at least one aperture that is configured to connect to a center or about the center of a yoke mast section.

6. The hub system of claim 5, wherein the at least one aperture comprises multiple apertures, and wherein the multiple apertures are aligned in a cruciform shape.

7. The hub system of claim 1, wherein the at least one mast adapter comprises an inner plate and an outer plate, wherein the inner plate is configured to transfer torque to the at least one yoke, and wherein the outer plate is configured to control flapping and feathering of the at least one yoke.

8. A hub system comprising:

a stacked yoke;

a mast adapter,

wherein the mast adapter is configured to transfer rotation from a rotor mast to the hub system to rotate the hub system about a central axis of rotation, and

wherein the mast adapter is configured to attach to and support the stacked yoke such that each yoke in the stacked yoke is configured accommodate at least some amount of rotation about an axis that is perpendicular to or about perpendicular to the central axis of rotation.

9. The hub system of claim 8, wherein the mast adapter comprises apertures in a cruciform pattern, and wherein the apertures are configured to connect to a center or about the center of a mast section of each yoke in the stacked yoke.

10. The hub system of claim 8, wherein the mast adapter comprises an outer plate and an inner plate, wherein the inner plate is configured to transfer the rotation from the rotor mast to the stacked yoke, and wherein the outer plate is configured to control out-of-plane motion and spanwise torsion of the stacked yoke.

11. The hub system of claim 10, wherein the inner plate is configured to absorb shear strain from a flexure section of the stacked yoke to reduce an amount of shear strain in apertures of the stacked yoke.

12. The hub system of claim 11, wherein the inner plate comprises a composite material or a metal.

13. The hub system of claim 8, wherein the mast adapter comprises a flexure section that is configured to attach to and support the stacked yoke.

14. The hub system of claim 13, wherein the flexure section comprises an I-shaped cross-section or a V-shaped cross-section.

15. The hub system of claim 13, wherein the flexure section is integrally formed with the mast adapter, or wherein the flexure section and the mast adapter comprise separate components.

16. A hub system comprising:

a mast adapter;

a stacked yoke;

a spring mechanism,

wherein the mast adapter is configured to support the stacked yoke and the spring mechanism,

wherein the mast adapter is configured to restrain the stacked yoke in in-plane and out-of-plane directions, and

wherein the spring mechanism is configured to control a bent shape of yokes in the stacked yoke.

17. The hub system of claim 16, wherein the spring mechanism comprises a leaf spring.

18. The hub system of claim 16, wherein the spring mechanism comprises a cantilevered plate that is parallel to a yoke arm and that is affixed to a cantilevered support structure that is configured to apply force in a flapping direction.

19. The hub system of claim 16, wherein the spring mechanism is selected from a group consisting of a coil, a torsional, an elastomeric, or a flexure type spring mechanism.

20. The hub system of claim 16, wherein the spring mechanism comprises multiple spring mechanisms, and wherein the multiple spring mechanisms are spaced along a span of a flexure of the stacked yoke to create multiple virtual hinge points in the stacked yoke.