Control surface actuation mechanism

Abstract

The invention provides a control surface actuation mechanism for moving a control surface relative to a fixed airfoil portion of an aircraft. The control surface actuation mechanism comprises a hinged support, a sliding member on the hinged support and coupled to the control surface, the sliding member being arranged to slide relative to the hinged support, a track having a path for attachment to the fixed airfoil portion, and a rigid connecting element connected to the first track and to the sliding member. A first end of the first rigid connecting element is configured to be passively moved along the path as the sliding member is driven by an actuator to slide relative to the hinged support.

Description

Technical Field

[0001] The present invention relates to a control surface actuation mechanism for moving a control surface relative to a fixed airfoil portion of an aircraft. Background Technology

[0002] Control surface actuation mechanisms can use multiple cams to achieve various deflections of the desired control surface. These mechanisms can be complex, bulky, require long manufacturing lead times, and increase drag due to their extension into the airflow. Summary of the Invention

[0003] According to one aspect of the invention, a control surface actuation mechanism is provided for moving a control surface relative to a fixed airfoil portion of an aircraft, the control surface actuation mechanism comprising: a hinged support for pivotally coupled to the fixed airfoil portion about a generally spanwise pivot axis; a sliding member having a proximal end mounted on the hinged support and a distal end for coupling to the control surface, the sliding member being arranged to slide relative to the hinged support along a generally chordally oriented axis; a first track for attaching to the fixed airfoil portion and defining a first path; and a first rigid connecting element connected at a first end to the first track and at a second end to the sliding member, wherein the first end of the first rigid connecting element is configured to passively move along the first path as the sliding member is driven by an actuator to slide relative to the hinged support.

[0004] Another aspect of the present invention provides an airfoil for an aircraft, the airfoil including a fixed airfoil portion, a control surface, and an actuation mechanism of the first aspect.

[0005] The advantage of this invention is that it allows for simpler control of the translation and / or rotation of the control surface with fewer components than before. Instead of translation of the control surface caused by a sliding member driven by a hinged support, the path of the track can cause rotation of the control surface by rotating the hinged support using a rigid connecting element. The path of the track can be customized to provide a specific control surface response, allowing control over the degree of translation and rotation of the control surface at all stages of deployment.

[0006] Here, the term "approximate span" refers to the direction approximately along the span within a small angular difference.

[0007] Here, the term "approximately chordal" refers to the direction approximately along the chordal direction within a small angular difference.

[0008] The term "rigid connection element" as used herein refers to a connection element with a fixed length, meaning that the connection element is essentially inextensible.

[0009] The first rigid connecting element can be pivotally connected to the first track at its first end. Although the first rigid connecting element is capable of moving along the first track, it can also pivot relative to the first track at any point along the track. This can assist the first end of the first rigid connecting element in moving along the track when the track path has a non-linear portion, thus allowing the angle of the first rigid connecting element relative to a local path of the track to change.

[0010] The first rigid connecting element can be pivotally connected to the sliding member at the second end.

[0011] The first path can have a nonlinear component.

[0012] The nonlinear portion of the first path allows the relative rates of translation of the sliding member and rotation of the hinged support to change as the sliding member moves. This then enables the degree of translation and rotation of the control surface to be varied at different stages / states of control surface unfolding.

[0013] The hinged support can be configured to rotate about a spanwise pivot axis in response to the movement of the first end of the first rigid connecting element along the first track.

[0014] This can provide passive rotation of the articulated support determined by the path of the first track, such that both rotation and translation of the control surface at any stage / state of deployment can be predetermined by the position of the first end of the first rigid connecting element along the path of the first track.

[0015] The control surface can translate relative to the hinged support as the slider translates.

[0016] This allows control surfaces to translate relative to the fixed airfoil portion of the aircraft, thereby altering the aerodynamic profile of the wing.

[0017] The control surface actuation mechanism may include a second rigid connection element that may be connected at a first end to a sliding member and at a second end to a second track defining a second path, wherein the second end of the second rigid connection element may be configured to move along the second path.

[0018] The control surface actuation mechanism may include a third rigid connection element, wherein the third rigid connection element causes the control surface to rotate relative to the hinged support.

[0019] This can provide additional rotation of the control surface relative to the rotation provided by the first track and the hinged support, to achieve greater deflection.

[0020] The second end of the third rigid connecting element may coincide with the second end of the second rigid connecting element.

[0021] Both the second and third rigid connecting elements can be driven from the point of overlap between the two rigid connecting elements.

[0022] The third rigid connecting element can be connected to the third track that defines the third path.

[0023] The third rigid connecting element that causes the control surface to rotate relative to the hinged support can change the motion of the third rigid connecting element according to the path of the third track.

[0024] The first end of the third rigid connecting element can be connected to the second sliding member, which has a proximal end mounted on the hinge support and a distal end for coupling to the control surface. The sliding member can be arranged to slide relative to the hinge support along a generally chordal axis.

[0025] The relative position of the two sliding members can provide additional control over the actuation of the control surface.

[0026] Hinged supports can provide the aerodynamic outer surface of airfoils.

[0027] This has the following advantages: the hinged support can form a movable aerodynamic surface that compensates for the unfolding of the control surface and reduces drag.

[0028] The fixed airfoil section may have a rear spars and a tail rib, and the first track may be located on the tail rib.

[0029] Here, the term "spar" is used to refer to any major supporting structure that extends roughly spanwise along the airfoil. The term "rib" is used to refer to a structural member that extends roughly chordally along the airfoil. "Tail" refers to a location towards the rear or tail of the aircraft, such that a tail rib is typically located closer to the tail of the aircraft.

[0030] The actuator can be a linear actuator. A linear actuator can be arranged to have an output that moves parallel to the rear spar. Alternatively, a rotary actuator type or any other actuator type suitable for driving the articulated mechanism can be used. Attached Figure Description

[0031] Embodiments of the present invention will now be described with reference to the accompanying drawings, in which:

[0032] Figure 1 It is a plan view of the aircraft;

[0033] Figure 2 It is a plan view of the starboard wing of the aircraft;

[0034] Figure 3aA perspective view of the control surface actuation mechanism in its unfolded or retracted state is shown;

[0035] Figure 3b A side view of the control surface actuation mechanism in its unfolded or retracted state is shown;

[0036] Figure 4a It shows the second state in which it is unfolded. Figures 3a to 3b A three-dimensional view of the control surface actuation mechanism;

[0037] Figure 4b It shows the second state in which it is unfolded. Figures 3a to 3b Side view of the control surface actuation mechanism;

[0038] Figure 5a It shows the third state of being unfolded. Figures 3a to 3b A three-dimensional view of the control surface actuation mechanism; and

[0039] Figure 5b It shows the third state of being unfolded. Figures 3a to 3b Side view of the control surface actuation mechanism. Detailed Implementation

[0040] Figure 1 A typical fixed-wing aircraft 1 is shown, comprising a left-side wing 2 and a starboard wing 3 supporting wing-mounted engines 9, with wings 2 and 3 extending from a fuselage 4. The fuselage has a nose 5 and a tail 6, wherein a horizontal stabilizing surface 7 and a vertical stabilizing surface 8 are located near the tail 6. The wingtips include wingtip devices 10. Aircraft 1 is a typical jet-powered passenger aircraft, but the invention is applicable to a wide variety of fixed-wing aircraft types, including commercial, military, passenger, cargo, jet, propeller, and general aviation, wherein any number of engines are attached to the wings or fuselage.

[0041] Each wing 2, 3 of aircraft 1 has a cantilever structure extending from the root to the tip along the spanwise direction, with the root connected to the fuselage 4. Wings 2 and 3 are structurally similar, therefore only reference will be made to them. Figure 2 A detailed description of the starboard wing 3 is provided.

[0042] The wing 3 has multiple flight control surfaces. Adjacent to the leading edge of the wing 3 are slats 12 distributed along the wingspan of the wing 3, ailerons 13 are provided on the outer section of the trailing edge of the wing, and an air brake / spoiler 14 is provided across the upper surface of the wing 3 toward the trailing edge.

[0043] The trailing edge of wing 3 has an inner flap 15 adjacent to the wing root and an outer flap 15 facing the aileron 13 on the outer side of the inner flap. It is worth noting that, due to the flap actuation mechanism described in detail below, the flap 15 preferably does not have an associated flap track fairing located on the underside of wing 3. This improves the aerodynamic performance of the aircraft.

[0044] Although aircraft 1 is shown as having a specific number and configuration of control surfaces, it will be understood that wings 2 and 3 may include control surfaces of different numbers and / or arrangements.

[0045] Figures 3 through 5 illustrate the control surface actuation mechanism in detail. This mechanism is particularly suitable as an actuation mechanism for flaps, but it will be understood that the mechanism can be applied to different control surfaces, such as ailerons, flaps, spoilers, elevators, slats, or other control surfaces of an aircraft.

[0046] exist Figures 3a to 3b In the diagram, the movable flight control surface 15 is shown in a neutral position, meaning that the flight control surface 15 is retracted and not actuated to the deployed position, and is at the zero-degree position of the flight control surface 15.

[0047] The mechanism includes hinged supports 30 attached to three tail ribs 20 (only the central tail rib 20 is shown) via pivoting connections, wherein the tail ribs 20 are attached to the rear wing spars 25 and form part of the fixed airfoil portion of the wing 3. The pivoting connections include hinge brackets 32 attached to the hinged supports 30 and hinge rods or hinge pins 33 fitted into holes in the tail ribs 20, allowing the hinged supports 30 to rotate relative to the fixed airfoil portion. The hinge rod 33 on the central tail rib 20 is shown as hollow, allowing the drive shaft 51 of the linear actuator 50 to be fitted within the hinge rod 33.

[0048] The sliding member 40 is configured to slide on the hinged support 30. The hinged support 30 includes a channel 36 that guides the sliding member 40 in a generally chordal direction. The sliding member 40 is attached at one end to the control surface 15 using a rigid control link 46. The interconnection between the control surface 15, the hinged support 30, and the sliding member 40 means that any translation of the sliding member 40 causes a translation of the control surface, and any rotation of the hinged support 30 causes a rotation of the control surface 15 relative to the fixed airfoil portion.

[0049] A rigid connecting element 42 connects the sliding member 40 to the track 48 on the central tail rib 20. The first end of the rigid connecting element 42 engages the track 48 and is movable along the track 48. The second end of the rigid connecting element 42 is connected to the sliding member 40 at a fixed point on the sliding member 40.

[0050] The first end of the rigid connecting element 42 is configured to pivot about the track 48, and the first end of the rigid connecting element 42 is able to move (translate) along the track 48.

[0051] The sliding member 40 is driven by an actuator 50, which is attached to the sliding member 40 via a second rigid connecting element 44 and a rigid actuator link 52. The second rigid connecting element 44 is connected to the sliding member 40 at a first end and to a follower 59 engaging the second track 58 at a second end. The first end of the rigid actuator link 52 is also connected to the follower 59, such that the first end of the rigid actuator link 52 coincides with the second end of the second rigid connecting element 44. The rigid actuator link 52 is directly connected to the actuator 50.

[0052] The second sliding member 60 is adjacent to the first sliding member 40 and configured to slide parallel to the first sliding member 40 on the hinge support 30. The second sliding member 60 is attached to the control surface 15 at one end using a second rigid control link 66. The second sliding member 60 moves in a second channel (not shown) on the hinge support 30 such that the second sliding member 60 moves relative to the hinge support 30 in a generally chordal direction.

[0053] The second sliding member 60 is driven by the actuator 50 via the third rigid connecting element 62, the rigid track link 64, and the actuator link 52. The second sliding member 60 is attached to the first end of the rigid track link 64, while the second end of the rigid track link 64 is connected to the second follower 69. The second follower 69 engages the third track 68, and also forms a connection between the second end of the rigid track link 64 and the first end of the third rigid connecting element 62. The second end of the third rigid connecting element 62 is connected to the first follower 59 on the second track 58, and thus the second end of the third rigid connecting element 62 coincides with the first end of the connector 52 and the second end of the second rigid connecting element 44.

[0054] Both the first control link 46, to which the first sliding member 40 is attached to the control surface 15, and the second control link 66, to which the second sliding member 60 is attached to the control surface 15, are attached to the control surface 15 at different chordal positions on the control surface, such that translation of one sliding control link 46, 66 relative to the other sliding control link causes rotation of the control surface 15 relative to both the fixed airfoil portion and the hinged support 30. In this embodiment, the second control link is attached near the leading edge of the control surface, and the first control link is attached to the control surface 15 towards the center chord of the control surface behind the connection of the second control link 66, although it will be clear that the first and second control links can be arranged in different ways, such that, for example, the second control link 66 is attached to the control surface 15 behind the first control link 46.

[0055] The actuation of the control surface using the actuation mechanism will now be described with reference to Figures 3 to 5.

[0056] Actuator 50 is shown in FIG. 3 in a first position corresponding to its minimum deployed state, such that the movable flight control surface 15 is shown in a zero-degree or neutral position. When actuator 50 is activated, actuator 50 is able to move along drive shaft 51 towards Figures 4a to 4b Proceed to the second position shown.

[0057] When the actuator 50 moves toward the second position, the actuator 50 drives the first follower 59 along the second track 58, thereby causing the first sliding member 40 and the second sliding member 60 to translate relative to the hinged support 30.

[0058] The first sliding member 40 is connected to the second track 58 via the second rigid connecting element 44, such that the translation of the first sliding member 40 is determined by the path of the second track 58.

[0059] The second sliding member 60 is connected to the second track 58 via the third track 68, allowing the second sliding member 60 to translate relative to the first sliding member 40. The difference in translation between the first sliding member 40 and the second sliding member 60 is determined by the path of the third track 68.

[0060] This difference in translation between the first sliding member 40 and the second sliding member 60 causes the control surface 15 to rotate relative to the hinged support 30, which is due to the resultant torque arm of the two control links 46, 66 attached to the control surface 15 at different chord positions.

[0061] When the first sliding member 40 translates, the first end of the first rigid connecting element 42 moves passively along the first track 48. As shown in Figures 3 and 4, the section of the first track 48 between the first position and the second position of the first end of the first rigid connecting element is linear and parallel to the hinge support 30, so that there is no reaction force between the first rigid connecting element and the first track.

[0062] Figures 4a to 4b The control surface 15 is shown in an deployed state (or second state), in which the control surface is relative to... Figures 3a to 3b The unfolded (retracted) state shown has been rotated by approximately 15 degrees. The control surface has been rotated by the different translations of the two sliding members 40 and 60, and the control surface has also been translated backward by the translation of the first sliding member 40.

[0063] Figures 5a to 5b It shows relative to Figures 3a to 3b The unexpanded (retracted) state shown is rotated approximately 27 degrees and relative to... Figures 4a to 4b The control surface shown is rotated 12 degrees in the second state and is in the third state.

[0064] Figures 5a to 5b The actuator 50 is shown located at a third position along the drive shaft 51. The operation of the actuator mechanism when the actuator 50 travels between the second and third positions is substantially the same as the operation previously described with respect to the movement of the actuator 50 between the first and second positions, except that the portion of the first track traveled by the first end of the first connecting element 42 includes a non-linear portion.

[0065] As the first sliding member 40 translates along the channel 36, the first end of the first rigid connecting element 42 moves along a non-linear section of the track 48 that changes the direction of the track 48's path. Due to the shape of the track 48, the distance between the first track 48 and the first sliding member 40 decreases. However, the first rigid connecting element 42 connecting the first sliding member 40 and the first track 48 has a fixed length, and thus maintains the distance between the first end of the first sliding member 40 and the first rigid connecting element 42. This results in a reaction force against the first track 48, which presses against the first sliding member 40 and causes the hinge support 30 to rotate about its spanwise pivot axis.

[0066] The connection between the hinged support 30 and the control surface 15 via the sliding member 40 causes the control surface 15 to reciprocate in response to rotation of the hinged support 30. This means that the first sliding member 40 provides translation to the control surface 15 by sliding relative to the hinged support 30, and rotation of the hinged support 30 provides rotation of the control surface 15. The rotation of the hinged support 30 is controlled by the path of the first track 48. Additional rotation of the control surface 15 can be provided by sliding the second sliding member 60 relative to the first sliding member 40.

[0067] The actuation mechanism is thus able to control the translation and / or rotation of the control surface 15 using a single actuator 50 without extensive use of cams and cam systems, thereby reducing manufacturing lead time, weight and volume.

[0068] By employing the aforementioned actuation mechanism, such as those shown in Figures 3 to 5, the size of the flap guide fairing traditionally associated with flap actuation mechanisms can be significantly reduced, or even eliminated altogether. In this case, the hinged support can provide a portion of the wing's external aerodynamic surface.

[0069] The path of the first track 48 is shown as having two substantially linear regions on either side of the nonlinear portion, which provide translation and rotation of the control surface 15. The path of track 48 may provide a greater number of nonlinear regions such that the entire path is nonlinear, or it may not provide any nonlinear regions such that the path is substantially linear. The path of track 48 can be varied to provide pure translation, pure rotation, or a combination of translation and rotation at different stages / states of control surface deployment. The path of track 48 is shown as providing a positive radian change to the airfoil sections of wings 2 and 3 due to the downward deflection / rotation of the control surface. Alternatively, the path of track 48 may be adapted to provide a negative radian through the upward deflection / rotation of the control surface 15.

[0070] The second track 48 and the third track 68 are shown as having linear paths. Alternatively, the second track 48 and the third track 68 may have nonlinear paths to control the movement of the corresponding connecting elements attached to the second track 48 and the third track 68. For example, the third track 68 may have a nonlinear path capable of increasing or decreasing the translation of the second sliding member 60 relative to the first sliding member, thereby increasing or decreasing the rotational rate of the control surface 15.

[0071] The first track 48 on the tail rib 20 can alternatively be a through slot in the tail rib 20, allowing the first rigid connecting element 42 to be connected from either side of the tail rib 20 or via both sides. The track 48 can alternatively be positioned on the fixed airfoil section or any other suitable part of the fixed support structure.

[0072] Sliding members 40 and 60 are guided by channel 36; however, the sliding members can be guided by any suitable alternative. For example, the first sliding member 40 can alternatively be guided by the first rigid connecting element 42 via the first track 48.

[0073] It will be understood that the pivoting connection on the articulated support 30 can be any suitable mechanism to provide rotation from the fixed airfoil section about a generally spanwise axis. For example, the pivoting connection could be a mating hinge connecting the articulated support 30 to the rear spar 25.

[0074] The actuation mechanism may not include a second sliding member 60 that slides independently of the first sliding member 40, such that rotation and / or translation of the control surface 15 are provided solely by the corresponding movement of the first sliding member 40 and the corresponding rotation of the hinged support 30. Alternatively, further rotation may be provided by extending or retracting one of the first control link 46 or the second control link 66.

[0075] Actuator 50 is shown as a linear actuator. Alternatively, the mechanism can be adapted to use rotary actuators, chain actuators, or other similar types of actuators known to those skilled in the art. Actuator 50 can be powered by any suitable means, such as hydraulic, pneumatic, or electrical devices.

[0076] In some embodiments, the sliding members 40, 60 may not be driven by actuators via the second track 58 and the third track 68. Alternatively, the sliding members 40, 60 may be directly driven by one or more actuators 50.

[0077] When the word “or” appears, it should be interpreted as meaning “and / or”, such that the terms involved are not necessarily mutually exclusive, and the terms involved can be used in any appropriate combination.

[0078] Although the invention has been described above with reference to one or more preferred embodiments, it will be understood that various changes or modifications may be made without departing from the scope of the invention as defined in the appended claims.

Claims

1. A control surface actuation mechanism for moving a control surface relative to a fixed airfoil portion of an aircraft, the control surface actuation mechanism comprising: A hinged support member for pivotally connecting to the fixed airfoil portion about a generally spanwise pivot axis; A sliding member having a proximal end mounted on the hinge support and a distal end for coupling to the control surface, the sliding member being arranged to slide relative to the hinge support along a generally chordal axis; A first track, the first track being used to attach to the fixed airfoil portion and define a first path; as well as A first rigid connecting element is connected at a first end to the first track and at a second end to a fixed point on the sliding member. The first end of the first rigid connecting element is configured to move passively along the first path as the sliding member is driven by an actuator to slide relative to the hinged support.

2. The control surface actuation mechanism according to claim 1, wherein, The first rigid connecting element is pivotally connected to the first track at its first end.

3. The control surface actuation mechanism according to claim 1 or 2, wherein, The first rigid connecting element is pivotally connected to the sliding member at the second end.

4. The control surface actuation mechanism according to claim 1 or 2, wherein, The first path has a nonlinear component.

5. The control surface actuation mechanism according to claim 1 or 2, wherein, The hinged support is configured to rotate about the spanwise pivot axis in response to movement of the first end of the first rigid connecting element along the first track.

6. The control surface actuation mechanism according to claim 1 or 2, wherein, The control surface translates relative to the hinged support as the sliding member translates.

7. The control surface actuation mechanism according to claim 1 or 2, comprising a second rigid connecting element, the second rigid connecting element being connected at a first end to the sliding member and at a second end to a second track defining a second path, wherein, The second end of the second rigid connecting element is configured to move along the second path.

8. The control surface actuation mechanism according to claim 1 or 2, comprising a third rigid connecting element, wherein, The third rigid connecting element causes the control surface to rotate relative to the hinged support.

9. The control surface actuation mechanism according to claim 7, comprising a third rigid connecting element, wherein, The third rigid connecting element causes the control surface to rotate relative to the hinged support, and wherein the second end of the third rigid connecting element coincides with the second end of the second rigid connecting element.

10. The control surface actuation mechanism according to claim 8, wherein, The third rigid connecting element is connected to the third track that defines the third path.

11. The control surface actuation mechanism according to claim 8, wherein, The first end of the third rigid connecting element is connected to a second sliding member, the second sliding member having a proximal end mounted on the hinge support and a distal end for coupling to the control surface, the sliding member being arranged to slide relative to the hinge support along a generally chordal axis.

12. An airfoil for an aircraft, comprising a fixed airfoil portion, a control surface, and an actuation mechanism as described in any one of claims 1 to 11.

13. The airfoil of the aircraft according to claim 12, wherein, The hinged support provides the aerodynamic outer surface of the airfoil.

14. The airfoil of the aircraft according to claim 12 or 13, wherein, The fixed airfoil portion has a rear spar and a tail rib, and the first track is located on the tail rib.

15. The airfoil of the aircraft according to claim 14, wherein, The actuator is a linear actuator that moves parallel to the rear spar.

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