SYSTEM FOR DRIVING A FLAP ARRANGEMENT BETWEEN A RETRACTED POSITION AND AN EXTENDED POSITION

Abstract

A flap system for driving a flap arrangement between a retracted and an extended position comprises a main flap, a covering flap, a main link, an auxiliary link and a connecting link. The main link comprises a first main link joint for rotatably supporting the main link on a first structurally fixed point, and a second main link joint rigidly coupled with the main flap. The connecting link, the auxiliary link and the main link are arranged to actively place the covering flap forward of the main flap in a retracted position of the main flap and rearward of the main flap in at least one extended position of the main flap.

Claims

1. A flap system for driving a flap arrangement between a retracted position and an extended position, the system comprising: a main flap, a covering flap, a main link, an auxiliary link, and a connecting link, wherein the main link comprises a first main link joint for rotatably supporting the main link on a first structurally fixed point, and a second main link joint rigidly coupled with the main flap, wherein the connecting link comprises a first connecting link joint for rotatably supporting the connecting link on a second structurally fixed point, which is located rearward of the first structurally fixed point, and further comprises a second connecting link joint, wherein the auxiliary link comprises a first auxiliary link joint coupled with the main link at a distance to the first main link joint, and further comprises a second auxiliary link joint coupled with the covering flap, wherein the second connecting link joint is coupled with the auxiliary link at a third auxiliary link joint between the first auxiliary link joint and the second auxiliary link joint, for rotatably supporting the connecting link on the auxiliary link, and wherein the connecting link, the auxiliary link and the main link are arranged to actively place the covering flap forward of the main flap in a retracted position of the main flap and rearward of the main flap in at least one extended position of the main flap.

2. The system of claim 1, wherein the main link has an L-shape.

3. The system of claim 1, wherein the main link has a first main link section that extends from the first main link joint in a direction of the second main link joint up to a transition region, wherein the main link has a second main link section that extends from the transition region in a direction of the second main link joint, and wherein the second main link section has a width in a direction parallel to a swivel axis of the first main link joint that is greater than a width of the first main link section.

4. The system of claim 1, wherein the main link comprises a recess extending vertically to a swivel axis of the first main link joint, and wherein the recess is designed for moving at least the connecting link and the covering flap through the recess when moving the main flap.

5. The system of claim 3, wherein the main link comprises a recess extending vertically to a swivel axis of the first main link joint, wherein the recess is designed for moving at least the connecting link and the covering flap through the recess when moving the main flap, and wherein the recess extends into the second main link section.

6. The system of claim 1, wherein the covering flap has a width that exceeds the width of at least a part of the main link in a direction parallel to a swivel axis of the first main link joint.

7. The system of claim 1, wherein the second auxiliary link joint comprises a rigid connection with the covering flap.

8. The system of claim 1, wherein the third auxiliary link joint is arranged less than 25% away from a center of the auxiliary link.

9. The system of claim 1, wherein the connecting link extends into a direction of the first main link joint when the main flap is in the retracted position.

10. A wing having a leading edge region and a trailing edge region, as well as at least one system according to claim 1 installed inside the wing.

11. The wing according to claim 10, wherein the system is arranged in the leading edge region.

12. The wing according to claim 10, wherein the wing comprises a cut-out for receiving at least a part of the main link, and wherein the covering flap is configured to cover the cut-out in the retracted position of the main flap.

13. An aircraft having at least one wing according to claim 10.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Other characteristics, advantages and potential applications of the present invention result from the following description of the exemplary embodiments illustrated in the figures. In this respect, all described and/or graphically illustrated characteristics also form an object of the invention individually and in arbitrary combination regardless of their composition in the individual claims or their references to other claims. Furthermore, identical or similar objects are identified by the same reference symbols in the figures.

[0036] FIG. 1 shows a flap system according to the invention in a retracted state at a leading edge of a wing in a schematic lateral view.

[0037] FIG. 2 shows a flap system according to the invention in a half extended state at a leading edge of a wing in a schematic lateral view.

[0038] FIG. 3 shows a flap system according to the invention in an extended state at a leading edge of a wing in a schematic lateral view.

[0039] FIG. 4 shows a flap system according to the invention in an extended state at a leading edge of a wing in a three-dimensional view.

[0040] FIG. 5 shows an aircraft having wings comprising at least one flap system according to the invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0041] FIG. 1 shows a flap system 2 arranged in a leading edge region 4 of a wing 6 of an aircraft. The flap system 2 comprises a main flap 8, a covering flap 10, a main link 12, a connecting link 14 and an auxiliary link 16. The main flap 8 has a profile with a flap leading edge 18 and a flap trailing edge 20. It may be designed similar to a common Krueger flap and the illustration in the figures is merely schematic.

[0042] In FIG. 1, the main flap 8 is completely retracted and is placed in an underside of the wing 6. Here, the main flap 8 is in an upside-down orientation, i.e., the leading edge 18 points rearwardly, the trailing edge 20 points forwardly and an upper side 22 points downwardly. The main flap 8 can be moved into an extended position by rotating the main link 12 around a first structurally fixed point 24, at which a first main link joint 26 is placed. This motion is indicated by a curved arrow around the first structurally fixed point 24. The main flap 8 is attached to the main link 12 at a second main link joint 27, which is opposed to the first main link joint 26.

[0043] The main link 12 exemplarily comprises an L-shape. Here, a first main link section 44 that extends up to the first main link joint 26 represents a first leg of the L-shape. A second main link section 46, which is substantially arranged at a right angle to the first main link section 44 and extends up to the second main link joint 27, represents a second leg of the L-shape. Between both main link sections 44 and 46 a transition region 45 is present, which connects both main link sections 44 and 46 in a tangentially continuous manner.

[0044] The covering panel 10 has a crescent-shaped profile and is thinner than the main flap 8. In the retracted position, the covering flap 10 is placed forward of the main flap 8 and directly connects to the trailing edge 20 of the main flap 8. As demonstrated in further figures, the covering flap 10 is configured to cover a cut-out 28 for accommodating the main link 12 during an extension motion. This is further demonstrated in FIG. 3.

[0045] The covering flap 10 is attached to the auxiliary link 16 through a second auxiliary link joint 30, while in this illustration a first auxiliary link joint 32 is hidden by the main link 12. Preferably, the second auxiliary link joint 30 is configured to rigidly hold the covering flap 10 in a fixed geometric relationship.

[0046] The auxiliary link 16 comprises a third auxiliary link joint 34, to which the connecting link 14 is attached. Additionally, the connecting link 14 comprises a first connecting link joint 36, which is attached to a second structurally fixed position 38. The second structurally fixed position 38 is rearward of the first structurally fixed position 24.

[0047] By moving the main link 12 about the first structurally fixed point 24 and holding the connecting link 14 at the second structurally fixed point 38, the auxiliary link 16 rotates about the first auxiliary link joint 32. In the retracted position, i.e., an initial position, the connecting link 14 and the main link 12 cross each other.

[0048] In FIG. 2, the main flap 8 is actuated from the retracted (initial) position in FIG. 1 and is in the process of being moved to an extended position. The fully extended position is shown in FIG. 3, while in FIG. 2 the main flap 8 is placed between the retracted position and the fully extended position. Here, the main link 12 is moved about approximately 70 from the retracted position and the main flap 8 is clearly moved out of a recess 40, which is provided for accommodating the main flap 8 at an underside of the wing 6. Due to the connecting link 14 being held at the second structurally fixed point 38 by the first connecting link joint 36, the auxiliary link 16 is urged into an anti-clockwise rotation. The main link 12, however, rotates in a clockwise direction. During this motion, the covering flap 10 is moved rearwardly and passes the main link 12. Also, the auxiliary link 16 is arranged to conform the position of the main link 12. In this state, the main flap 8 and the covering flap 10 have changed their position order along a longitudinal axis, i.e., along the forward or rearward direction. The main flap 8 is almost completely forward of the covering flap 10.

[0049] In FIG. 3, the extension motion of the main flap 8 is completed. Here, it is visible that the main link 12 is forward of the trailing edge 20 in the retracted position of the main flap 8 (see FIG. 1). Here, the required additional cut-out 42 in the leading edge region 4 of the wing 6 is indicated by dashed lines. The cut-out 42 will be closed in the retracted position of the main flap 8 through the covering flap 10, but is now completely open to accommodate the main link 12.

[0050] In FIG. 3, the spatial relationship between the connecting link 14 and the auxiliary link 16 is further illustrated. Exemplarily, the connecting link 14 has a curved shape similar to a curved shape of the auxiliary link 16. The fixed length of the connecting link 14 leads to pulling the third auxiliary link joint 34 rearwardly away from the main link 12, thereby placing the covering flap 10 in a rearward position. The auxiliary link 16, the connecting link 14 as well as the second structurally fixed point 38 are chosen to place the covering flap 10 into a position as upwardly as possible and as inwardly as possible to reduce the additional aerodynamic resistance caused by the covering flap 10 in the extended position of the main flap 8.

[0051] It may also be preferred to arrange the resting surfaces and corresponding contacting surfaces of the covering flap in such manner that the covering flap experiences a certain pre-tension force between the resting surfaces and a rim section of the covering flap. The pre-tension force supports an exact alignment of the covering flap relative to the cut-out.

[0052] FIG. 4 provides a good overview of the flap system 2 in a three-dimensional view from below the flap system 2. Here, the different sections 44 and 46 of the main link 12 are apparent. The first main link section 44 and the second main link section 46 have different widths in a direction parallel to a swivel axis 48 of the first main link joint 26. Here, the first main link section 44 comprises a clearly smaller width w1 than the second main link section 46, which has a width w2. Exemplarily, w2 may be twice w1.

[0053] A recess 50 is apparent in the main link 12, which extends through the main link 12 vertically to the swivel axis 48. Due to the different widths of the main link section 44 and 46, the recess 50 is designed to have a T-shape. A wider part of the T-shape is arranged in the second main link section 46, while the narrower part of the T-shape is arranged in the first main link section 44. Since the cut-out 42 for accommodating the main link 12 only needs to receive the first main link section 44, the covering flap 10 only needs to cover a width slightly larger than the width w1 of the first main link section 44. This allows the covering flap 10 to pass through the recess 50. The auxiliary link 16, however, is able to pass through the part of the recess 50 arranged in the first main link section 44.

[0054] Due to the symmetric design of the main link 12, the auxiliary link 16 and the covering flap 10, it is advantageous to use two connecting links 14 instead of just one connecting link 14. They may be arranged parallel to each other to symmetrically enclose the auxiliary link 16. The arrangement of two connecting links 14 and one auxiliary link 16 is able to pass through the recess 50 as well. However, also a single connecting link 14 and two auxiliary links 16 may be used instead. In this case, the two auxiliary links 16 enclose the connecting link 14.

[0055] The first auxiliary link joint 32 may be placed inside the recess 50 and furthermore allows a very space-efficient design. For this purpose, the first main link section 44 may comprise two inner surfaces 47 that face each other. Here, two devices for coupling two first auxiliary link joints 32 are arranged. The devices may be threaded bore holes or other suitable devices.

[0056] Lastly, FIG. 5 shows an aircraft 52 having wings 6, which are equipped with flap systems 2 according to the previous drawings. For the sake of simplification, only potential installation positions are indicated, but recesses or cut-outs are left open.

[0057] 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.