Device for folding a blade, a blade, and an aircraft

Patent metadata

Field	Value
Publication number	US-9708058-B2
Application number	US-201414463981-A
Country	US
Kind code	B2
Filing date	Aug 20, 2014
Priority date	Aug 28, 2013
Publication date	Jul 18, 2017
Grant date	Jul 18, 2017

Abstract

A device ( 20 ) for folding a blade ( 5 ), the device comprising a fitting ( 30 ) and a cuff ( 50 ) connected to said fitting ( 30 ). The fitting ( 30 ) has at least one horizontal pin axis ( 31 ) perpendicular to a radial direction (AX 2 ) and a clevis ( 35 ) axially offset relative to the horizontal pin axis ( 31 ) in the radial direction (AX 2 ). The cuff ( 50 ) has an insert ( 51 ) inserted in said clevis ( 35 ), a vertical pin ( 70 ) passing through said clevis ( 35 ) and said insert ( 51 ). The cuff ( 50 ) includes at least one horizontal fastener pin axis ( 55 ) axially offset relative to said insert ( 51 ) along the radial direction (AX 2 ), at least one lateral arm ( 80 ) connects said horizontal pin axis ( 31 ) to said fastener pin axis ( 55 ).

First claim

What is claimed is:

1. A device for folding a blade that includes an airfoil extending in a radial direction and having a spar, the device comprising:
a fitting suitable for being secured to the spar of the airfoil, the fitting having a horizontal pin axis perpendicular to a radial direction of the fitting, and a vertical pin orifice axially offset relative to the horizontal pin axis of the fitting along the radial direction of the fitting;
a cuff connected to the fitting and suitable for being fastened to a hub, the cuff having a horizontal pin axis and a vertical pin orifice;
a vertical pin passing through the vertical pin orifice of the fitting and the vertical pin orifice of the cuff; and
a lateral arm connecting the horizontal pin axis of the fitting to the horizontal pin axis of the cuff in releasable manner so as to enable the fitting to pivot in rotation relative to the cuff about the vertical pin.

2. The device according to claim 1 , wherein the fitting and the cuff together define a clevis and an insert inserted in the clevis, the clevis and the insert each presenting the vertical pin orifices of the fitting and of the cuff.

3. The device according to claim 2 , wherein the clevis comprises a top lug and a bottom lug, each lug and the insert having the vertical pin passing therethrough.

4. The device according to claim 1 , wherein the fitting includes a clevis that extends from the horizontal pin axis of the fitting in the radial direction of the fitting, the clevis including the vertical pin orifice of the fitting;
the cuff includes an insert offset axially from the horizontal pin axis of the cuff, the insert including the vertical pin orifice of the cuff, the insert being arranged in the clevis by bringing the vertical pin orifice of the fitting into coincidence with the vertical pin orifice of the insert; and
the vertical pin passes through the clevis and the insert.

5. The device according to claim 4 , wherein the fitting is T-shaped, the horizontal pin axis of the fitting extending transversely along a first branch of the T-shape, while the clevis extends along a second branch of the T-shape orthogonal to the first branch.

6. The device according to claim 1 , wherein the cuff includes a clevis extending from the horizontal pin axis of the cuff in the radial direction of the fitting, the clevis including the vertical pin orifice of the cuff;
the fitting includes an insert axially offset from the horizontal pin axis of the fitting, the insert including the vertical pin orifice of the fitting, the insert being arranged in the clevis of the cuff by bringing the vertical pin orifice of the fitting into coincidence with the vertical pin orifice of the insert; and
the vertical pin passes through the clevis and the insert.

7. The device according to claim 1 , wherein at least one horizontal pin axis includes at least one bushing and a pin that passes through the bushing and the lateral arm in a horizontal pin direction.

8. The device according to claim 1 , wherein the horizontal pin axis of the fitting is situated between the vertical pin and the horizontal pin axis of the cuff.

9. The device according to claim 1 , wherein the horizontal pin axis of the fitting and the horizontal pin axis of the cuff are situated axially on opposite sides of the vertical pin.

10. The device according to claim 1 , wherein the lateral arm includes a damper.

11. The device according to claim 1 , wherein the fitting has an additional horizontal pin axis, and the two horizontal pin axes of the fitting are offset from each other.

12. The device according to claim 1 , wherein the cuff has an additional horizontal pin axis, and the two horizontal pin axes of the cuff are offset relative to each other.

13. The device according to claim 1 wherein the lateral arm is disposed laterally outside of the fitting and the cuff.

14. A blade assembly having an airfoil extending spanwise in a radial direction, wherein the blade assembly includes the device according to claim 1 , and the fitting is secured to the airfoil.

15. The blade assembly according to claim 14 , wherein the airfoil includes a spar, the spar including at least one horizontal tape wound in a horizontal plane and surrounding the vertical pin orifice of the fitting for transmitting forces that result from flapping movement of the airfoil, the spar including at least one vertical tape wound in a vertical plane and surrounding the horizontal pin axis of the fitting in order to transmit forces that result from lead-lag movement of the airfoil.

16. An aircraft provided with a rotor having a hub and a plurality of blade assemblies, wherein each blade assembly is a blade assembly according to claim 14 , each cuff being attached to the hub by hinge and retaining means.

17. The blade assembly according to claim 14 , wherein the airfoil includes a spar, the spar including at least one horizontal portion extending in a horizontal plane radially inwardly of the vertical pin orifice of the fitting for transmitting forces that result from flapping movement of the airfoil, the spar including at least one vertical portion extending in a vertical plane inwardly of the horizontal pin axis of the fitting in order to transmit forces that result from lead-lag movement of the airfoil.

18. An aircraft provided with a rotor having a hub and a plurality of blade assemblies, wherein each blade assembly is a blade assembly according to claim 14 , each cuff being attached to the hub by a hinge.

19. A device for folding a blade that includes an airfoil extending in a radial direction and having a spar, the device for folding comprising:
a fitting suitable for being secured to the spar of the airfoil, the fitting having a horizontal pin axis and a vertical pin orifice offset relative to the horizontal pin axis of the fitting;
a cuff to be connected to the fitting and suitable for being fastened to a hub, the cuff having a horizontal pin axis and a vertical pin orifice;
a vertical pin that is insertable into the vertical pin orifice of the fitting and the vertical pin orifice of the cuff; and
a lateral arm for connecting the horizontal pin axis of the fitting to the horizontal pin axis of the cuff in a releasable manner so as to enable the fitting to pivot relative to the cuff about the vertical pin;
wherein the horizontal pin axis of the fitting and the horizontal pin axis of the cuff are situated on opposite sides of the vertical pin when the vertical pin is disposed in the vertical pin orifice of the fitting and the vertical pin orifice of the cuff.

20. A device for folding a blade that includes an airfoil extending in a radial direction and having a spar, the device for folding comprising:
a fitting suitable for being secured to the spar of the airfoil, the fitting having two horizontal pin axes that are offset from each other, and a vertical pin orifice offset relative to the horizontal pin axes of the fitting;
a cuff to be connected to the fitting and suitable for being fastened to a hub, the cuff having a horizontal pin axis and a vertical pin orifice;
a vertical pin to pass through the vertical pin orifice of the fitting and the vertical pin orifice of the cuff; and
a lateral arm for connecting one of the horizontal pin axes of the fitting to the horizontal pin axis of the cuff in a releasable manner so as to enable the fitting to pivot relative to the cuff about the vertical pin.

Assignees

• Airbus Helicopters

Inventors

• Gaffiero Jacques
• Amari Andre

Classifications

• F04D29/36

  adjustable {(flexible blades F04D29/382)} · CPC title

• B64C27/50 Primary

  Blades foldable to facilitate stowage of aircraft · CPC title

• F04D29/34

  Blade mountings {(for axial flow compressors F04D29/322)} · CPC title

• B64C27/48

  Root attachment to rotor head · CPC title