RELATING TO AIRCRAFT WINGS

Abstract

An aircraft including an aircraft wing wherein the aircraft wing includes a fixed wing, a wing tip device at an end of the fixed wing, and a wing tip device actuator configured to move the wing tip device between a flight configuration and a ground configuration. The wing tip device actuator includes a shaft which is rotatable about a shaft axis to selectively displace respective first and second elbows of the wing tip device actuator towards or away from the shaft. The first elbow is connected to the wing tip device and the second elbow is connected to the fixed wing such that movement of the respective elbows away from the shaft causes the wing tip device to move away from the flight configuration and such that movement of the respective elbows towards the shaft causes the wing tip device to move towards the flight configuration.

Claims

1. A wing tip device actuator configured to move a wing tip device of an aircraft wing with respect to a fixed wing of the aircraft wing, the wing tip device actuator comprising: a first pair of arms, each arm having a first and second end, a second pair of arms, each arm having a first and second end, and a threaded shaft, each pair of arms comprising an elbow where the first ends of the arms are hinged to one another, and a connection to the threaded shaft at the second ends of the arms, wherein rotation of the threaded shaft causes the elbows of the arms to move towards or away from the threaded shaft, and the elbow of the first pair of arms configured to engage with the wing tip device and the elbow of the second pair of arms configured to engage with the fixed wing, such that rotation of the threaded shaft causes the wing tip device to move relative to the fixed wing.

2. The wing tip device actuator as claimed in claim 1, wherein each of the first pair of arms is connected to the threaded shaft via respective threaded sleeve assemblies, and each of the second pair of arms is connected to the threaded shaft via respective threaded sleeve assemblies.

3. The wing tip device actuator as claimed in claim 2, wherein one arm of the first pair of arms and one arm of the second pair of arms share a threaded sleeve assembly, and a second arm of the first pair of arms and a second arm of the second pair of arms also share a threaded sleeve assembly.

4. The wing tip actuator as claimed in claim 1, further comprising a drive unit, the drive unit configured to drive the rotation of the threaded shaft.

5. The wing tip actuator as claimed in claim 1, further comprising a control link, the control link comprising a first end through which the threaded shaft extends, and a second end configured to engage with part of a substructure of the wing tip device or fixed wing.

6. An aircraft comprising an aircraft wing, the aircraft wing comprising: a fixed wing and a wing tip device at a tip thereof, wherein the wing tip device is configurable between: (i) a flight configuration for use during flight and (ii) a ground configuration for use during ground-based operations, in which ground configuration the wing tip device is rotated away from the flight configuration about a hinge axis such that a span of the aircraft wing is reduced, and a wing tip device actuator according to claim 1, configured to move the wing tip device between the flight configuration and the ground configuration.

7. The aircraft according to claim 6, wherein the wing tip device actuator further comprises: a shaft, and a first sleeve assembly, a second sleeve assembly, and a control link arranged upon the shaft; the control link is rotatably mounted upon the shaft at a first end and is rotatably mounted to a substructure of the aircraft wing at an opposite second end; each of the first sleeve assembly and the second sleeve assembly comprises an internally threaded sleeve engaged with a threaded portion of the shaft and a bearing sleeve coupled to the internally threaded sleeve, the bearing sleeve being free to rotate about the shaft, one arm of the first pair of actuating arms is pivotally connected to the internally threaded sleeve of the first sleeve assembly and the other arm of the first pair of actuating arms is pivotally connected to the internally threaded sleeve of the second sleeve assembly; one arm of the second pair of actuating arms is pivotally connected to the bearing sleeve of the first sleeve assembly and the other arm of the second pair of actuating arms is pivotally connected to the bearing sleeve of the second sleeve assembly; the internally threaded sleeve of the first sleeve assembly is engaged with a first threaded portion of the shaft and the internally threaded sleeve of the second sleeve assembly is engaged with a second threaded portion of the shaft; and the first threaded portion and second threaded portion have opposing thread directions such that rotation of the shaft about a shaft axis causes the first sleeve assembly and the second sleeve assembly to move in mutually opposing directions along the shaft to selectively displace the respective elbows of the first pair of actuating arms and the second pair of actuating arms towards or away from the shaft; wherein an engagement of the elbow of the first pair of arms with the fixed wing and an engagement of the elbow of the second pair of arms with the wing tip device is such that movement of the respective elbows away from the shaft causes the wing tip device to rotate about the hinge axis away from the flight configuration and is such that movement of the respective elbows towards the shaft causes the wing tip device to rotate about the hinge axis towards the flight configuration.

8. The aircraft according to claim 7, wherein the control link is rotatable about an axis of the substructure which is parallel with the hinge axis.

9. The aircraft according to claim 7, wherein the aircraft wing comprises a hinge pin connecting the fixed wing and the wing tip device; the wing tip device is rotatable about the hinge pin between the flight configuration and the ground configuration; and the substructure of the aircraft wing to which the control link is rotatably mounted is the hinge pin.

10. The aircraft according to claim 7, wherein the control link is rotatably mounted upon the shaft by the shaft being situated within a first hole provided in the control link; and the control link is rotatably mounted to the substructure of the aircraft wing by the substructure being situated within a second hole provided in the control link.

11. The aircraft according to claim 7, wherein the control link is rotatably mounted upon the shaft between the first threaded portion of the shaft and the second threaded portion of the shaft.

12. The aircraft according to claim 7, wherein the control link is prevented from moving along the shaft axis.

13. The aircraft according to claim 7, wherein the wing tip device actuator comprises one or more additional control links, wherein each control link is rotatably mounted upon the shaft at a first end and is rotatably mounted to a substructure of the aircraft wing at an opposite second end.

14. The aircraft according to claim 7, wherein the shaft axis is parallel with the hinge axis.

15. The aircraft according to claim 7, wherein the bearing sleeve of the first sleeve assembly comprises a first sleeve part situated on a first side of the internally threaded sleeve and a second sleeve part situated on an opposite second side of the internally threaded sleeve; and the first sleeve part and the second sleeve part are connected by a connecting member that spans over the internally threaded sleeve.

16. The aircraft according to claim 15, wherein the connecting member of the first sleeve assembly comprises a flange to which an arm of the second pair of actuating arms is pivotally connected.

17. The aircraft according to claim 7, wherein one or both of the first sleeve assembly and the second sleeve assembly comprises a flange which extends from an outer surface of the internally threaded sleeve and an arm of the first pair of actuating arms is pivotally connected to the flange.

18. The aircraft according to claim 7, wherein the aircraft wing comprises a roller screw actuator coupled to the shaft of the wing tip device actuator and the roller screw actuator is configured to rotate the shaft to move the wing tip device between the flight configuration and the ground configuration.

19. An aircraft wing configured as the aircraft wing of the aircraft of claim 7.

20. A wing tip device actuator for moving a wing tip device of an aircraft wing with respect to a fixed wing of the aircraft wing, wherein: the wing tip device actuator comprises a shaft, and a first sleeve assembly, a second sleeve assembly, and a control link arranged upon the shaft; the control link is rotatably mounted upon the shaft at a first end and is configured to be rotatably mounted to a substructure of the aircraft wing at an opposite second end; each of the first sleeve assembly and the second sleeve assembly comprises an internally threaded sleeve engaged with a threaded portion of the shaft and a bearing portion coupled to the internally threaded sleeve, the bearing portion being free to rotate about the shaft, the wing tip device actuator further comprises a first pair of actuating arms and a second pair of actuating arms, each pair of actuating arms comprising an elbow at which the respective actuating arms of the pair are pivotally connected to one another, one elbow being configured to engage with the fixed wing and the other elbow being configured to engage with the wing tip device; one arm of the first pair of actuating arms is pivotally connected to the internally threaded sleeve of the first sleeve assembly and the other arm of the first pair of actuating arms is pivotally connected to the internally threaded sleeve of the second sleeve assembly; one arm of the second pair of actuating arms is pivotally connected to the bearing portion of the first sleeve assembly and the other arm of the first pair of actuating arms is pivotally connected to the bearing portion of the second sleeve assembly; the internally threaded sleeve of the first sleeve assembly is engaged with a first threaded portion of the shaft and the internally threaded sleeve of the second sleeve assembly is engaged with a second threaded portion of the shaft; and the first threaded portion and second threaded portion have opposing thread directions such that rotation of the shaft about an axis of the shaft causes the first sleeve assembly and the second sleeve assembly to move in mutually opposing directions along the shaft to selectively displace the respective elbows of the first pair of actuating arms and the second pair of actuating arms towards or away from the shaft.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Embodiments of the present disclosure will now be described by way of example only with reference to the accompanying schematic drawings of which:

[0030] FIG. 1 shows a plan view of an aircraft according to an embodiment of the invention;

[0031] FIG. 2 shows a frontal view of the aircraft of FIG. 1;

[0032] FIG. 3 is a perspective view of a wing tip device actuator of the aircraft;

[0033] FIG. 4 is a bottom elevation view of the wing tip device actuator;

[0034] FIGS. 5A to 5C are schematic views of a portion of a wing of the aircraft which show the wing tip device in a flight configuration, an intermediate configuration, and a ground configuration, respectively; and

[0035] FIGS. 6A to 6C are perspective views of a portion of the wing of the aircraft which show the wing tip device in a flight configuration, an intermediate configuration, and a ground configuration, respectively.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0036] FIGS. 1 and 2 show a plan view and a front view of an aircraft 1 according to an embodiment of the invention. The aircraft 1 comprises two wings 3 extending outwardly from the fuselage (only one wing is fully visible in FIG. 2). Each wing 3 comprises a fixed wing 5 extending from a root 7 to a tip 9. At the tip 9 of the fixed wing 5, the wing 3 also comprises a moveable wing tip device 11. In this embodiment, the wing tip device 11 comprises a planar wing tip extension. The wing tip device 11 is rotatably mounted on a hinge joint 13, having a hinge axis Y. As such, the wing tip device 11 is able to rotate about the hinge joint 13 relative to the fixed wing 5.

[0037] Referring to FIG. 2, the wing tip device 11 is rotatable about the hinge joint 13 between a flight configuration and a ground configuration. FIG. 2 also shows the wing tip device 11 in an intermediate configuration, part-way between the flight configuration and the ground configuration.

[0038] In the flight configuration, the wing tip device 11 is an extension of the fixed wing 5. Accordingly, the upper and lower surfaces of the fixed wing 5 are continuous with the upper and lower surfaces of the wing tip device 11. The leading and trailing edges of the fixed wing 5 are also continuous with the respective leading and trailing edges of the wing tip device 11.

[0039] In the ground configuration, the wing tip device 11 is oriented in a substantially upright position such that the effective span of the wing 3 is reduced. The movable wing tip device 11 therefore enables the aircraft 1 to have a relatively large wingspan during flight and to comply with airport gate limits when on the ground.

[0040] The wing tip device 11 is moved between the ground configuration and the flight configuration by a wing tip device actuator 100, which is shown in isolation in FIG. 3 and FIG. 4. The wing tip device actuator 100 comprises a shaft 103, and a first sleeve assembly 105A, a second sleeve assembly 105B, and a plurality of control links 107A-C arranged upon the shaft 103.

[0041] The first sleeve assembly 105A and the second sleeve assembly 105B are substantially identical, apart from having internally threaded sleeves 111A, 111B which are internally threaded in opposing directions for reasons which are described below. The first and second sleeve assemblies 105A, 105B will therefore be described with reference to the first sleeve assembly 105A only. However, the features that the second sleeve assembly 105B has in common with the first sleeve assembly 105A are labelled in the figures with the same reference numerals as used herein to refer to the features of the first sleeve assembly but suffixed with B instead of A.

[0042] The first sleeve assembly 105A comprises an internally threaded sleeve 111A and a bearing sleeve 123A. The bearing sleeve 123A comprises a first sleeve part 133A which surrounds and is rotatably mounted upon the shaft 103 on a first side of the internally threaded sleeve 111A and a second sleeve part 135A which surrounds and is rotatably mounted upon the shaft 103 on an opposite second side of the internally threaded sleeve 111A. The first sleeve part 133A is connected to the second sleeve part 135A by a connecting member comprising a flange 137A which is provided with a hole. A similarly arranged flange 139A provided with a hole extends from an outer surface of the internally threaded sleeve 111A.

[0043] Configured as described above, the bearing sleeve 123A is free to rotate about the shaft 103 but is coupled to the position of the internally threaded sleeve 111A and is prevented from moving along the axis X of the shaft 103 independently of the internally threaded sleeve 111A by the first sleeve part 133A and second sleeve part 135A abutting with the first threaded sleeve 111A. However, when the internally sleeve 111A moves along the shaft 103, the internally threaded sleeve 111A abuts with either the first sleeve part 133A or the second sleeve part 135A to move the bearing sleeve 123A along the shaft 103 with the internally threaded sleeve 111A.

[0044] A first pair of actuating arms 115A, 115B and a second pair of actuating arms 127A, 127B are connected between the first sleeve assembly 105A and the second sleeve assembly 105B. The first pair of actuating arms comprises a first arm 115A and a second arm 115B. The first arm 115A is pivotally connected to the flange 139A of the internally threaded sleeve 111A of the first sleeve assembly 105A at a first end 117A of the first arm 115A. Likewise, the second arm 115B is pivotally connected to the flange 139B of the internally threaded sleeve 111B of the second sleeve assembly 105B at a first end 117B of the second arm 115B. At the respective second ends 118A, 118B of the first and second arms 115A, 115B, the first and second arms 115A and 115B are pivotally connected to one another at a first elbow 141.

[0045] The second pair of actuating arms comprises a first arm 127A and a second arm 127B. The first arm 127A is pivotally connected to the flange 137A of the bearing sleeve 123A of the first sleeve assembly 105A at a first end 129A of the first arm 127A. Likewise, the second arm 127B is pivotally connected to the flange 137B of the bearing sleeve 123B of the second sleeve assembly 105B at a first end 129B of the second arm 127B. At the respective second ends 131A, 131B of the first and second arms 127A, 127B, the first and second arms 127A and 127B are pivotally connected to one another at a second elbow 143.

[0046] The shaft 103 comprises a first threaded portion 119A and a second threaded portion 119B arranged along an axis X of the shaft 103, the first threaded portion 119A and the second threaded portion 119B having opposing thread directions. The internally threaded sleeve 111A of the first sleeve assembly 105A is engaged with the first threaded portion 119A of the shaft 103 and the internally threaded sleeve 111B of the second sleeve assembly 105B is engaged with the second threaded portion 119B of the shaft 103. The wing tip device actuator 100 is thereby arranged such that rotation of the shaft 103 about the shaft axis X causes the first and second threaded portions 119A, 119B of the shaft 103 to engage with the internally threaded sleeves 111A, 111B of the first and second sleeve assemblies 105A, 105B to move the first and second sleeve assemblies 105A, 105B in mutually opposing directions along the shaft 103, thereby displacing first elbow 141 and the second elbow 143 towards or away from the shaft 103.

[0047] The wing tip device actuator 100 is configured to be rotatably mounted to a substructure of the aircraft wing 3 via the control links 107A-C. A first control link 107A is situated on the shaft 103 between the first threaded portion 119A of the shaft 103 and the second threaded portion 119B of the shaft 103. A second control link 107B is spaced apart along the shaft 103 from the first control link 107A on a first side of the first control link 107A such the first sleeve assembly 105A is positioned between the first control link 107A and the second control link 107B. A third control link 107C is spaced apart along the shaft 103 from the first control link 107A on an opposite second side of the first control link 107A such that the second sleeve assembly 105B is positioned between the first control link 107A and the third control link 107C. Each of the control links 107A comprises a first hole 145 in which the shaft 103 is received and a second hole 147 which is configured to rotatably receive a substructure of the aircraft wing 3, such as a hinge pin 15 of the hinge joint 13.

[0048] FIGS. 5A to 5C are schematic drawings showing the wing tip device actuator 100 connected between the fixed wing 5 and the wing tip device 11 of the aircraft wing 3, with FIG. 5A showing the wing tip device 11 in the flight configuration, FIG. 5B showing the wing tip device 11 in the intermediate configuration, and FIG. 5C showing the wing tip device 11 in the ground configuration. FIGS. 6A to 6C are corresponding perspective views of the aircraft wing 3 in each of the configurations shown in FIGS. 5A to 5C, respectively.

[0049] With reference to FIG. 5A, the wing tip device actuator 100 is arranged such that the hinge pin 15 of the hinge joint 13 is received in the holes 147 of each of the control links 107A-C. The shaft axis X of the wing tip device actuator 100 is therefore parallel with the hinge axis Y, the hinge axis Y being defined by the hinge pin 15 (note that the shaft axis X and the hinge axis Y extend out of the page in FIG. 5A). The first elbow 141 is connected to a substructure 17 of the wing tip device 11 and the second elbow 143 is connected to a substructure 19 of the fixed wing 5. The aircraft wing comprises a roller screw actuator 21 which is coupled to the shaft 103 of the wing tip device actuator 100 and configured to rotate the shaft 103 to thereby move the wing tip device 11 between the flight configuration and the ground configuration.

[0050] As can be seen in FIG. 5A, when the wing tip device 11 is in the flight configuration, the first elbow 141 and second elbow 143 of the wing tip device actuator 100 are situated on opposing sides of the shaft 103, with the first pair of actuating arms 115A, 115B and second pair of actuating arms 127A, 127B being approximately parallel with one another. Note that FIG. 3 and FIG. 4 also show the wing tip device actuator 100 configured to the flight configuration shown in FIG. 5A.

[0051] In order to move the wing tip device 11 to the ground configuration, the roller screw actuator 21 is operated to rotate the shaft 103 in a first direction to displace the elbows 141, 143 away from the shaft, thereby causing the first elbow 141 to push the substructure 17 of the wing tip device 11 away from the substructure 19 of the fixed wing 5 to rotate the wing tip device 11 about the hinge axis Y. Because the position of the hinge pin 15 is fixed with respect to the substructure 19 of the fixed wing 5, the wing tip device actuator 100 is forced to rotate about the hinge pin 15 as the second elbow 143 is moved away from the shaft, as can be best seen by comparing FIGS. 5A to 5C. Furthermore, because the second pair of actuating arms 127A, 127B is free to rotate about the shaft 103, the first pair of actuating arms 115A, 115B follows the rotation of the wing tip device 11 as the wing tip device 11 is moved to the ground configuration. This arrangement may ensure that actuating force is optimally transferred from the wing tip device actuator into the wing tip device as it rotates. Furthermore, protrusions from the wing geometry in the vicinity of the hinge are minimized when the wing tip device is in the ground configuration by the wing tip device actuator effectively folding with the wing tip device. It will of course be understood that in order to move the wing tip device 11 from the ground configuration to the flight configuration, the screw actuator 21 is operated to rotate the shaft 103 in an opposite second direction to move the elbows 141, 143 towards the shaft, thereby causing the wing tip device 11 to be rotated about the hinge axis Y towards the flight configuration.

[0052] While the present invention has been described and illustrated with reference to particular embodiments, it will be appreciated by those of ordinary skill in the art that the invention lends itself to many different variations not specifically illustrated herein. For example, while the example described above comprises a first elbow engaged with the wing tip device and a second elbow engaged with the fixed wing, in some embodiments the first elbow may be engaged with the fixed wing and the second elbow may be engaged with the wing tip device. Additionally, while the elbows of the example described above are formed by the ends of pivotally connected arms, in some embodiments of the invention an elbow may alternatively be formed by an intermediate member pivotally connected between the arms.

[0053] In some embodiments, either or both of the sleeve assemblies may be configured similarly to the sleeve assemblies 105A, 105B described above but with the internally threaded sleeve becoming the bearing sleeve and the bearing sleeve becoming the internally threaded sleeve; in these embodiments the internally threaded sleeve may comprise an internally threaded first sleeve part situated on a first side of the bearing sleeve and an internally threaded second sleeve part situated on an opposite second side of the bearing sleeve. In a similar embodiment where the internally threaded sleeve comprises two sleeve parts, only one of the sleeve parts may be internally threaded; for example, the internally threaded sleeve may comprise an internally threaded first sleeve part situated on a first side of the bearing sleeve and a second sleeve part situated on an opposite second side of the bearing sleeve, wherein the second sleeve part is not internally threaded but may instead be configured similarly to one of the sleeve parts of the bearing sleeve of the first and second sleeve assemblies 105A, 105B described above.

[0054] Where in the foregoing description, integers or elements are mentioned which have known, obvious or foreseeable equivalents, then such equivalents are herein incorporated as if individually set forth. Reference should be made to the claims for determining the true scope of the present invention, which should be construed so as to encompass any such equivalents. It will also be appreciated by the reader that integers or features of the invention that are described as preferable, advantageous, convenient or the like are optional and do not limit the scope of the independent claims. Moreover, it is to be understood that such optional integers or features, while of possible benefit in some embodiments of the invention, may not be desirable, and may therefore be absent, in other embodiments.

[0055] While at least one exemplary embodiment of the present invention(s) is disclosed herein, it should be understood that modifications, substitutions and alternatives may be apparent to one of ordinary skill in the art and can be made without departing from the scope of this disclosure. This disclosure is intended to cover any adaptations or variations of the exemplary embodiment(s). In addition, in this disclosure, the terms comprise or comprising do not exclude other elements or steps, the terms a or one do not exclude a plural number, and the term or means either or both. Furthermore, characteristics or steps which have been described may also be used in combination with other characteristics or steps and in any order unless the disclosure or context suggests otherwise. This disclosure hereby incorporates by reference the complete disclosure of any patent or application from which it claims benefit or priority.