Dual flex-beam assembly for folding rotor blade

Patent metadata

Field	Value
Publication number	US-11225324-B2
Application number	US-201916414882-A
Country	US
Kind code	B2
Filing date	May 17, 2019
Priority date	May 17, 2019
Publication date	Jan 18, 2022
Grant date	Jan 18, 2022

Abstract

A rotor blade for a rotary wing aircraft includes a rotor hub including a first flex-beam attachment member and a flex-beam assembly. The flex-beam assembly includes a flex-beam support member having an attachment end and a wrapping end. A first flex-beam includes a first end, a second end and an intermediate portion. The first end of the first flex-beam is connected at the first flex-beam attachment member and the second end of the first flex-beam being connected to the attachment end of the flex-beam support member. A second flex-beam includes first end portion, a second end portion and an intermediate section. The first end portion of the second flex-beam is connected at the first flex-beam attachment member, the second end portion of the second flex-beam being connected at the second flex-beam attachment member and the intermediate section extending about the wrapping end of the flex-beam support member.

First claim

What is claimed is:

1. A rotor blade system for a rotary wing aircraft comprising:
a rotor hub including a first flex-beam attachment member and a second flex-beam attachment member;
a rotor blade which generates lift for the rotor blade system; and
a flex-beam assembly supporting the rotor blade system and connected to the rotor hub, the flex-beam assembly comprising:
a flex-beam support member spaced from the rotor hub and having an attachment end and a wrapping end, the rotor blade rotatably attached to and extending from the flex-beam support member;
a first flex-beam including a first end, a second end and an intermediate portion, the first end of the first flex-beam being connected at the first flex-beam attachment member and the second end of the first flex-beam being connected to the attachment end of the flex-beam support member; and
a second flex-beam including first end portion, a second end portion and an intermediate section, the first end portion of the second flex-beam being connected at the first flex-beam attachment member, the second end portion of the second flex-beam being connected at the second flex-beam attachment member and the intermediate section extending about the wrapping end of the flex-beam support member.

2. The rotor blade system according to claim 1 , further comprising: a third flex-beam including a first end section, a second end section and an intermediate segment, the first end section of the third flex-beam being connected at the second flex-beam attachment member and the second end section of the third flex-beam being connected at the attachment end of the flex-beam support.

3. The rotor blade system according to claim 1 , wherein the first flex-beam defines an inner beam and the second flex-beam defines an outer beam.

4. The rotor blade system according to claim 1 , wherein the first flex-beam is connected to the flex-beam support member with at least one fastener.

5. The rotor blade system according to claim 1 , wherein the flex-beam support member defines a hinge end having an opening between the attachment end and a wrapping end, the rotor blade being attached to a hinged end.

6. The rotor blade system according to claim 5 , further comprising: a torque tube mounted to at least one of the first and second flex-beams.

7. The rotor blade system according to claim 6 , wherein the torque tube is included within the rotor blade, which is arranged at the hinge end.

8. The rotor blade system according to claim 1 , wherein the first flex-beam attachment member includes a first attachment element and a second attachment element spaced from the first attachment element by a gap, wherein the first end of the first flex-beam is connected between the first and second attachment elements in the gap, and the first end portion of the second flex-beam is connected to an inner surface of the second attachment element.

9. A rotary wing aircraft comprising:
a fuselage;
at least one prime mover supported in the fuselage;
a rotor assembly operatively connected to the at least one prime mover, the rotor assembly including a rotor hub including a first flex-beam attachment member, a second flex-beam attachment member, and a rotor blade system mounted to the rotor hub, the rotor blade system including a flex-beam assembly supporting the rotor blade system and connected to the rotor hub, the flex-beam assembly comprising:
a flex-beam support member spaced from the rotor hub and having an attachment end and a wrapping end, a rotor blade being rotatably attached to and extending from the flex-beam support member;
a first flex-beam including a first end, a second end and an intermediate portion, the first end being connected at the first flex-beam attachment member and the second end being connected to the attachment end of the flex-beam support member; and
a second flex-beam including first end portion, a second end portion and an intermediate section, the first end portion being connected at the first flex-beam attachment member, the second end portions being connected at the second flex-beam attachment member and the intermediate section extending about the wrapping end of the flex-beam support member.

10. The rotary wing aircraft according to claim 9 , further comprising: a third flex-beam including a first end section, a second end section and an intermediate segment, the first end section being connected at the second flex-beam attachment member and the second end section being connected at the attachment end of the flex-beam support.

11. The rotary wing aircraft according to claim 9 , wherein the first flex-beam defines an inner beam and the second flex-beam defines an outer beam.

12. The rotary wing aircraft according to claim 9 , wherein the first flex-beam is connected to the flex-beam support member with at least one fastener.

13. The rotary wing aircraft according to claim 9 , wherein the flex-beam support member defines a hinged end having an opening between the attachment end and a wrapping end, the rotor blade being attached to the hinged end.

14. The rotary wing aircraft according to claim 13 , further comprising: a torque tube extending about the flex-beam assembly.

15. The rotary wing aircraft according to claim 14 , wherein the rotor blade system is connected to the torque tube, the rotor blade system being configured to pivot about the hinge end.

Assignees

• Lockheed Corp

Inventors

• Baskin Bryan Kenneth

Classifications

• B64C27/06

  with single rotor · CPC title

• B64C27/50

  Blades foldable to facilitate stowage of aircraft · CPC title

• B64C27/33 Primary

  having flexing arms · CPC title

• B64C27/48 Primary

  Root attachment to rotor head · CPC title

• B64C27/37

  having articulated joints · CPC title