REMOVABLE LIFT ASSEMBLY FOR A ROTORCRAFT, AND A ROTORCRAFT

• US 20150284076A1
• Filed: 04/01/2015
• Published: 10/08/2015
• Est. Priority Date: 04/07/2014
• Status: Active Grant

• Current Assignee: Airbus Helicopters
• Original Assignee: Airbus Helicopters
• Inventors: CACCIAGUERA, Bruno
• Granted Patent: US 9,738,379 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: B64C 1/26 Attaching the wing or tail units or stabilising surfaces
• CPC Class Codes: B64C 2211/00 Modular constructions of airplanes or helicopters
• CPC Class Codes: B64C 27/26 characterised by provision of fixed wings
• CPC Class Codes: B64C 27/32 Rotors
• CPC Class Codes: B64C 3/185 Spars

Abstract

A lift assembly that is releasably fastened to a fuselage of a rotorcraft. The lift assembly comprises a wing comprising at least two spars. A main gearbox passes through an opening in the suction side of a central box of the wing so that its bottom is attached to a resilient suspension system arranged level with the pressure side of the central box, a top of the main gearbox projecting from the central box and being fastened to at least one spar by at least three suspension bars. A reversible fastener system having a plurality of fastener means serves to fasten the central box reversibly to a plurality of fastener points of a fuselage.

Claims

1. A lift assembly for a rotorcraft, the lift assembly being for fastening in removable manner to a fuselage of a rotorcraft and comprising:

a fixed wing comprising in succession in a transverse direction;

a left lift segment;

a central box for fastening to a fuselage; and

a right lift segment;

the wing having at least two spars extending from the left lift segment to the right lift segment, the wing extending in elevation from a pressure side to a suction side and longitudinally from a leading edge to a trailing edge;

a main gearbox extending in elevation from a bottom towards a top, the main gearbox having a mast for setting in rotation a lift rotor, the main gearbox passing through an opening in the suction side of the central box so that the bottom of the main gearbox is attached to a resilient suspension system arranged at the level of the pressure side of the central box, the top projecting from the central box, the top being fastened to at least one spar by at least three suspension bars; and

a reversible fastener system having a plurality of fastener means for reversibly fastening the central box to a plurality of fastener points of the fuselage.

2. A lift assembly according to claim 1, wherein the wing has a leading edge spar and a trailing edge spar, and the assembly includes at least two front suspension bars each fastened via a fitting to the leading edge spar, and at least two rear suspension bars each fastened via a fitting to the trailing edge spar.

3. A lift assembly according to claim 2, wherein the central box extends transversely from a left side beam to a right side beam, each side beam extending longitudinally from a leading edge spar to a trailing edge spar, each side beam being secured to a stiffening piece extending between the side beam and one of the leading edge and trailing edge bars so that the central box defines a hollow inside space receiving the bottom of the main gearbox, each of the fittings being fastened to a spar and also to a stiffening piece and to a pressure side panel of the central box.

4. A lift assembly according to claim 1, wherein the resilient suspension system comprises a mount extending longitudinally from a leading edge spar to a trailing edge spar, the resilient suspension system co-operating with resilient suspension means interposed between the mount and the bottom.

5. A lift assembly according to claim 4, wherein the resilient suspension means comprises a link bar and a support that is fastened to the bottom, the link bar extending between two ends, a laminated damper being arranged between each end and the support and between each end and the mount.

6. A lift assembly according to claim 4, wherein the resilient suspension means comprises a plate having slots, the plate being connected to the mount and to the bottom.

7. A lift assembly according to claim 1, wherein the fastener system includes at least a front pair of fastener means secured to a leading edge spar and at least one rear pair of fastener means secured to a trailing edge spar, each pair having:

first fastener means for transmitting the forces to which the lift assembly is subjected as a result of movement in translation in elevation, or transversely, or movement in rotation about a longitudinal axis, about a transverse axis, or about an axis in elevation; and

second fastener means for transmitting the forces to which the lift assembly is subjected as a result of a movement in translation in elevation, or a movement in rotation about a longitudinal axis, about a transverse axis, or about an axis in elevation.

8. A lift assembly according to claim 7, wherein the first fastener means of a pair comprises a triangular plate having two top orifices for fastening to a spar, and a bottom orifice for fastening to a fuselage, the two top orifices being in alignment with each other along a transverse direction, one of the top orifices being vertically above a bottom orifice, and each orifice co-operating with a ball joint.

9. A lift assembly according to claim 7, wherein the second fastener means comprises a link in elevation having a top hole for fastening it to a spar, and a bottom hole for fastening it to a fuselage, the top hole being vertically above the bottom hole, and each hole co-operating with a ball joint.

10. A lift assembly according to claim 7, wherein the fastener means of a pair are arranged in a common plane.

11. A lift assembly according to claim 7, wherein the fastener system includes at least two longitudinal fasteners, each longitudinal fastener having at least one longitudinal link for transmitting the forces to which the lift assembly is subjected as a result of movement in longitudinal translation, each longitudinal link being provided with a first passage for fastening it to the central box and with a second passage for fastening it to a fuselage, each passage co-operating with a ball joint.

12. A lift assembly according to claim 1, wherein the lift assembly includes a rotor secured to the mast.

13. A lift assembly according to claim 1, wherein the lift assembly includes at least one main transmission shaft that is connected to the main gearbox and that is designed to be set into rotation by an engine.

14. A lift assembly according to claim 1, wherein the lift assembly includes at least one propeller carried by a lift segment of the wing, a secondary drive train connecting the propeller to the main gearbox.

15. A lift assembly according to claim 1, wherein each lift segment of the wing includes at least one wheel set of a landing gear suitable for standing on ground.

16. A rotorcraft having a fuselage together with a fixed wing and a lift rotor, the lift rotor being driven in rotation by a main gearbox connected to at least one engine, wherein the rotorcraft includes a lift assembly according to claim 1, the lift assembly comprising the wing and the main gearbox and the lift rotor, the lift assembly being fastened to the fuselage in reversible manner by the fastener system.

17. A rotorcraft according to claim 16, wherein the rotorcraft has at least two longitudinal lift beams, the central box being arranged over the lift beams and being fastened to the lift beams by two respective longitudinal links.

18. A rotorcraft according to claim 16, wherein the rotorcraft includes at least two lift frames extending in elevation, two spars of the lift assembly being fastened in reversible manner respectively to the two lift frames, each spar being fastened to a lift frame by a pair of fastener means.