CN210618452U

CN210618452U - Variable-inclination winglet and aircraft

Info

Publication number: CN210618452U
Application number: CN201920779634.XU
Authority: CN
Inventors: 张璐; 李明远; 石翔
Original assignee: Goertek Robotics Co Ltd
Current assignee: Goertek Robotics Co Ltd
Priority date: 2019-05-28
Filing date: 2019-05-28
Publication date: 2020-05-26
Anticipated expiration: 2029-05-28

Abstract

The utility model discloses a variable inclination winglet and aircraft, variable inclination winglet sets up in wing main body's spanwise end, winglet is including the first rib of connecting the wing main part, set up in the terminal fourth rib of winglet, be located the second rib between first rib and the fourth rib, and piezoelectric fiber driver, piezoelectric fiber driver includes base member steel sheet and piezoelectric fiber piece, first rib and second rib, be connected with piezoelectric fiber driver between second rib and the fourth rib respectively, constitute the changeover portion of winglet between first rib and the second rib, constitute the flexible section of winglet between second rib and the fourth rib, wing main body and flexible section are connected to the changeover portion, the girder is put to changeover portion and wing main body equipartition, first rib all links firmly with the girder with the second rib. The utility model discloses a piezoelectric fiber driver makes changeover portion and flexible section take place the linkage, realizes the deflection of wingtip winglet.

Description

Variable-inclination winglet and aircraft

Technical Field

The utility model relates to an aircraft technical field, concretely relates to variable inclination winglet and aircraft.

Background

For the modern air transportation industry, the drag reduction technology is one of effective ways to reduce the oil consumption of the airplane. For a large airplane, the induced resistance accounts for 40% of the total resistance in the cruising stage, and the percentage in the takeoff and climbing stage is up to 70%, so that the reduction of the induced resistance has important significance for the drag reduction of the airplane, and the wingtip winglet can well reduce the induced resistance.

At present, the inclination angle of the wingtip winglet is mostly fixed, the wingtip winglet is designed and optimized only for the cruise phase of a fixed-wing aircraft, and the drag reduction effect is poor in the takeoff and climbing phase of the aircraft. Moreover, because the cruising of the short-range flight path occupies less total time, the drag reduction effect of the conventional winglet is less obvious to the aircraft of the short-range flight path.

Accordingly, there is a need for a variable angle winglet to address the above-mentioned problems.

SUMMERY OF THE UTILITY MODEL

The utility model aims at providing a winglet with variable inclination to improve the drag reduction effect of winglet at the aircraft take-off, climb and cruise stage.

In order to achieve the above object, the present invention provides a winglet with variable inclination angle, which is disposed at the end of a wing body in a span direction, wherein the winglet comprises a first rib connected to the wing body, a fourth rib disposed at the end of the winglet, a second rib located between the first rib and the fourth rib, and a piezoelectric fiber driver, the piezoelectric fiber driver comprises a base steel sheet and a piezoelectric fiber sheet, the piezoelectric fiber driver is connected between the first rib and the second rib, and between the second rib and the fourth rib, the piezoelectric fiber driver is connected respectively, a transition section of the winglet is formed between the first rib and the second rib, a flexible section of the winglet is formed between the second rib and the fourth rib, the transition section connects the wing body and the flexible section, and a main beam is uniformly disposed on the transition section and the wing body, the first rib and the second rib are fixedly connected with the main beam.

Preferably, the winglet further includes a third rib located between the second rib and the fourth rib, the piezoelectric fiber driver is connected between the second rib and the third rib, and the piezoelectric fiber driver is connected between the third rib and the fourth rib, the flexible section includes a first-level flexible section and a second-level flexible section, the first-level flexible section of the winglet is formed between the second rib and the third rib, the second-level flexible section of the winglet is formed between the third rib and the fourth rib, and the first-level flexible section is provided with a rib-to-rib connecting plate.

Preferably, the inter-rib connecting plate is disposed below the piezoelectric fiber driver of the primary flexible segment, and opposite ends of the inter-rib connecting plate are respectively hinged to the second rib and the third rib.

Preferably, winglet still includes a fixed mechanism, a fixed mechanism is including the wedge that has fulcrum portion and the rigid connection piece that has the fulcrum groove, second rib and third rib are all installed the wedge, the changeover portion with two of one-level flexible section piezoelectric fiber driver one-level flexible section with two of second grade flexible section piezoelectric fiber driver all passes through the connecting block links firmly, fulcrum portion and fulcrum groove looks butt, its butt department forms the fulcrum so that the connecting block with the wedge can wind the fulcrum verts.

Preferably, second rib and third rib are all in logical groove has been seted up in the spanwise direction, the last cell wall that leads to the groove is installed respectively with lower cell wall the wedge, the connecting block passes logical groove and centre gripping in upper and lower two between the wedge, the upper and lower two surfaces of connecting block are sunken formation arc fulcrum groove respectively, the fulcrum portion butt respectively of two wedges the connecting block the tank bottoms of two fulcrum grooves.

Preferably, the wedge block is further provided with a limiting part for limiting the inclination angle of the connecting block relative to the wedge block.

Preferably, the two opposite ends of the connecting block in the wingspan direction are respectively recessed inwards to form a horizontally extending clamping groove for clamping the base steel sheet of the piezoelectric fiber driver, and the connecting block is further provided with a pin hole communicated with the clamping groove for fixing the base steel sheet.

Preferably, the first rib is provided with a slot, and after one end of the base steel sheet of the transition section passes through the slot, the base steel sheet protrudes up and down to form a blocking sheet abutting against the first rib so as to form a sliding pair.

Preferably, the main beam is of an i-beam structure and comprises an upper edge strip, a lower edge strip and a reinforcing plate, wherein the reinforcing plate is connected with the upper edge strip and the lower edge strip, the upper edge strip is respectively connected with the upper sides of the first rib and the second rib, the lower edge strip is respectively connected with the lower sides of the first rib and the second rib, the upper edge strip and the lower edge strip are arranged in an up-down alignment manner, the main beam is arranged close to the front edge of the wing main body in a chord direction perpendicular to the wingspan direction, and the piezoelectric fiber driver of the transition section is arranged perpendicular to the main beam and behind the main beam; the flexible section adopts a flexible skin, and the transition section and the wing main body adopt conventional skins.

Additionally, the utility model provides an aircraft, aircraft includes the winglet of the variable inclination wing tip.

The utility model discloses among the technical scheme, make changeover portion and flexible section take place the linkage through the piezoelectric fiber driver, realize the deflection of wingtip winglet, the utility model discloses a mechanism structure light in weight, can bear great moment of flexure of variable inclination wingtip winglet based on the piezoelectric fiber driver, and can be adapted to the little constraint condition of wingtip winglet inner space well.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed to be used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the structures shown in the drawings without creative efforts.

Figure 1 is a top view of the winglet of the invention in an initial design configuration;

FIG. 2 is a rear view of the winglet shown in FIG. 1 in an initial design configuration;

FIG. 3 is a rear view of the cruise design of the winglet of the invention;

FIG. 4 is a perspective view of the cruise design of the winglet shown in FIG. 2;

FIG. 5 is a cross-sectional view of the winglet of FIG. 1 taken along line I-I;

FIG. 6 is a cross-sectional view of the winglet shown in FIG. 1 taken along line II-II;

figure 7 is a schematic view of the cant angle of the winglet of the invention;

100, wingtip winglets, 200, a wing main body, 1, a main beam, 11, an upper edge strip, 13, a lower edge strip, 12, a reinforcing plate, A, a transition section, B1, a primary flexible section, B2, a secondary flexible section, 7, a piezoelectric fiber driver, 72, a piezoelectric fiber sheet, 71, a base steel sheet, 51, a first wing rib, 52, a second wing rib, 53, a third wing rib, 54, a fourth wing rib, 6, a fixing and supporting mechanism, 60, a gap, 62, a wedge block, 620, a fulcrum part, 621, a limiting part, 61, a connecting block, 610, a pin hole, 611, a fulcrum groove, 8 and a connecting plate between wing ribs

The objects, features and advantages of the present invention will be further described with reference to the accompanying drawings.

Detailed Description

The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative efforts belong to the protection scope of the present invention.

It should be noted that all the directional indicators (such as upper, lower, left, right, front and rear … …) in the embodiment of the present invention are only used to explain the relative position relationship between the components, the motion situation, etc. in a specific posture (as shown in the drawings), and if the specific posture is changed, the directional indicator is changed accordingly.

In addition, descriptions in the present application as to "first", "second", and the like are for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicit to the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature.

As shown in fig. 1 to 4, in an embodiment of the present disclosure, the winglet 100 is mounted at the end of the wing body 200 in the span direction, and the winglet 100 and the wing body 200 together form an aircraft wing. The winglet 100 has a cant angle with respect to the vertical plane as shown in fig. 7, and the winglet 100 is configured to include a piezoelectric fiber driver 7 to drive the winglet 100 to change its cant angle using an inverse piezoelectric effect. The inverse piezoelectric effect refers to the deformation of a piezoelectric material when an alternating electric field is applied to the piezoelectric material.

The piezoelectric fiber driver 7 comprises a base steel sheet 71 and a piezoelectric fiber sheet 72, wherein the piezoelectric fiber sheet 72 is made of a piezoelectric fiber composite material with the inverse piezoelectric effect, and the base steel sheet 71 has elastic bending deformation capability. The piezoelectric fiber sheet 72 and the base steel sheet 71 are connected into a whole, and the driving force for promoting the elastic bending deformation of the base steel sheet 71 is obtained by electrifying the piezoelectric fiber sheet 72 to generate the inverse piezoelectric effect. Alternatively, the piezoelectric fiber sheets 72 are adhered to the upper and lower surfaces of the base steel sheet 71, respectively.

The wing body 200 extends along the wingspan direction to form two opposite ends, one end is connected with an aircraft fuselage (not shown), the other end is connected with the winglet 100, the winglet 201 comprises a skin 201, and the skin 201 adopts a conventional skin and has no special requirement on flexibility. For convenience of description, the spanwise direction is defined as the inboard direction, the outboard direction, and the inboard direction.

In a first embodiment of the present invention, referring to fig. 1, the winglet 100 includes a first rib 51, a second rib 52, a third rib 53, a fourth rib 54, and three piezoelectric fiber drivers 7 connected to the first rib 51 and the second rib 52, the second rib 52 and the third rib 53, and the third rib 53 and the fourth rib 54, respectively. When the winglet 100 is not tilted, i.e. when the winglet 100 is in the initial design position, the first rib 51, the second rib 52, the third rib 53 and the fourth rib 54 are arranged in parallel, and the three piezoelectric fiber drivers 7 are arranged in a manner extending horizontally perpendicular to the first rib 51, the second rib 52, the third rib 53 and the fourth rib 54. In the spanwise direction, the first rib 51 and the second rib 52 form a transition section a of the winglet 100, the second rib 52 and the fourth rib 54 form flexible sections B1 and B2 of the winglet 100, the second rib 52 and the third rib 53 form a primary flexible section B1, and the third rib 53 and the fourth rib 54 form a secondary flexible section B2. The winglet 100 further comprises a skin (not shown) and a bracing mechanism 6. The transition section A of the winglet 100 is made of conventional skin, the flexible sections B1 and B2 are made of flexible skin, and the skin is fixedly attached to the side edges of the first rib 51, the second rib 52, the third rib 53 and the fourth rib 54. The fixing and supporting mechanism 6 includes a wedge block 62 having a supporting point portion 620, and a rigid connection block 61 having a supporting point groove 611. The fulcrum portion 620 forms a fulcrum at the abutment with the fulcrum groove 611 so that the connecting block 61 and the wedge block 62 can tilt about the fulcrum. In the present embodiment, the connecting pieces 61 are recessed inwardly at opposite ends in the span-wise direction to form horizontally extending holding grooves for holding the base steel sheet 71. The connecting block 61 is provided with a pin hole 610, and the pin hole 610 is communicated with the clamping groove to further fix the base steel sheet 71. In this embodiment, the wedge blocks 62 are perpendicular to the connecting blocks 61 when the winglet 100 is not tilted.

The transition section A is connected with the wing main body 200 and the flexible sections B1 and B2, and the main beams 1 are arranged on the transition section A and the wing main body 200. The main spar 1 extends spanwise to form opposite ends, one end being connected to the fuselage of the aircraft and the other end being connected to the second rib 52 for receiving the majority of the bending and shearing forces of the winglet 100. The first rib 51 is arranged between the second rib 52 and the aircraft fuselage, and the first rib 51 and the second rib 52 are fixedly connected with the main beam 1 respectively and arranged in parallel with each other. Specifically, the main beam 1 of the present embodiment uses an i-beam structure including an upper edge strip 11, a lower edge strip 13, and a reinforcing plate 12 connecting the upper edge strip 11 and the lower edge strip 13, the upper edge strip 11 connects upper sides of the first rib 51 and the second rib 52, respectively, the lower edge strip 13 connects lower sides of the first rib 51 and the second rib 52, respectively, and the upper edge strip 11 and the lower edge strip 13 are aligned in the vertical direction. In the chord direction perpendicular to the wingspan direction, the main beam 1 is arranged close to the leading edge of the wing, and the piezoelectric fiber driver 7 of the transition section A is perpendicular to the main beam 1 and is arranged behind the main beam 1.

Transition section A: referring to fig. 6, the first rib 51 is provided with a slot 510, one end of the base steel sheet 71 extends in a direction close to a fuselage of an aircraft (not shown), and after passing through the slot 510 of the first rib 51, the base steel sheet 71 protrudes up and down to form a blocking piece 711 abutting against the inner side of the first rib 51 to form a sliding pair. Referring to fig. 5, the other end of the base steel sheet 71 is connected to the flexible sections B1 and B2 through the connecting block 61, and after the base steel sheet 71 is inserted into the clamping groove of the connecting block 61, the base steel sheet 71 and the connecting block 61 are further fixed by using pins. The first rib 51 is provided with a through groove in the wingspan direction for the connecting block 61 to pass through, two wedge blocks 62 are respectively arranged on the upper groove wall and the lower groove wall of the through groove, and the connecting block 61 is clamped between the upper wedge block 62 and the lower wedge block 62. The upper and lower surfaces of the connecting block 61 are recessed to form fulcrum grooves 611 corresponding to the fulcrum portions 620 of the wedge blocks 62, the fulcrum grooves 611 are arc-shaped, and the fulcrum portions 620 of the two wedge blocks 62 abut against the groove bottoms of the upper and lower fulcrum grooves 611 of the connecting block 61. In this embodiment, each wedge block 62 is formed by assembling two small symmetrical wedge blocks, and is respectively installed on the inner side and the outer side of the upper slot wall/the lower slot wall, and the fulcrum 620 of this embodiment is formed by assembling the two small wedge blocks.

Referring to fig. 2 to 4, when the piezoelectric fiber driver 7 of the transition section a is energized, the base steel sheet 71 bends downward, and due to the restriction of the second rib 52, the connecting block 61 deflects around the fulcrum 620 of the wedge-shaped block 62, so as to drive the flexible sections B1 and B2 to deflect upward integrally. In the deflection process, a lever fulcrum is formed at the abutting part of the fulcrum part 620 and the fulcrum groove 611, and the piezoelectric fiber driver 7 of the transition section A forms a force application point. Wedge block 62 still is equipped with spacing portion 621, forms clearance 60 between spacing portion 621 and the connecting block 61, and when the angle of deflection of connecting block 61 for wedge block 62 reached the default, clearance 60 was zero, spacing portion 621 and connecting block 61 butt to prevent connecting block 61 further to deflect.

Primary flexible segment B1: the fixed connection modes of the two opposite ends of the base steel sheet 71 and the second wing rib 52 and the third wing rib 53 are respectively the same as the fixed connection modes of the base steel sheet 71 and the second wing rib 52 of the transition section a, and the two ends are connected through the fixed support mechanism 6, which is not described herein. Referring to fig. 2 and 3, the flexible sections B1, B2 of the winglet 100 include inter-rib webs 8 for connecting the second rib 52 to the third rib 53, and the inter-rib webs 8 are hinged to the second rib 52 and the third rib 53. Specifically, the inter-rib connecting plate 8 is disposed below the piezoelectric fiber driver 7. The inter-rib connecting plate 8 is used for limiting the deflection angle of the third rib 53 and further limiting the deflection angle of the connecting block 61 installed at the third rib 53, so that the third rib 53 and the connecting block 61 are perpendicular to or close to perpendicular to the connecting block 61 as much as possible, and by such arrangement, on one hand, interference between the connecting block 61 and the limiting part 621 of the wedge block 62 can be prevented, and on the other hand, the aerodynamic shape of the wing of the primary flexible section B1 can be adjusted, so that the wing does not change greatly due to tilting of the winglet 100.

Secondary flexible segment B2: the fastening manner of the base steel sheet 71 and the third wing rib 53 is the same as the fastening manner of the base steel sheet 71 and the second wing rib 52 of the transition section a, and the base steel sheet 71 and the third wing rib are connected by the fastening and supporting mechanism 6, which is not described herein again. The base steel sheet 71 is fixedly connected with the fourth rib 54 by the conventional means in the technical field, such as adhesion.

The inter-rib connecting plate 8 is arranged, on one hand, to keep the third rib 53 perpendicular to the base steel sheet 71 as much as possible and prevent hard interference between the connecting block 61 and the limiting portion 621 of the wedge block 62 when the base steel sheet 71 is bent, and on the other hand, the aerodynamic shape of the wing is determined by the shape of the skin, which is determined by the bending angle of the base steel sheet 71 and the inclination angle of the third rib 53, so that the inter-rib connecting plate 8 can change the aerodynamic shape of the wing by adjusting the inclination angle of the third rib 53.

The tilting procedure of the winglet 100 from the initial design position (see fig. 1 and 2) to the cruise design position (see fig. 3 and 4) is exemplified as follows:

after the transition section A is electrified, the flexible sections B1 and B2 are wholly biased, the third rib 53 is kept basically parallel to the second rib 52, and the inter-rib connecting plate 8 rotates around the hinge point along with the upper bias of the primary flexible section B1.

When the piezoelectric fiber driver 7 of the primary flexible segment B1 is subjected to bending deformation under the power-on action, the third rib 53 end of the primary flexible segment B1 deflects upwards, and further drives the secondary flexible segment B2 to deflect upwards as a whole. The third rib 53 is connected to the connecting block 61 in a point contact manner such that the third rib 53 does not deflect with the deflection of the connecting block 61, and at this time, the included angle between the third rib 53 and the connecting block 61 tends to become smaller. Because the inter-rib connecting plate 8 is hinged to the

second ribs

52 and 53 at two ends, the inter-rib connecting plate 8 rotates around a hinge point along with the bending of the piezoelectric fiber driver 7 of the first-stage flexible section B1, and because the second rib 52 is fixed along with the main beam 1, one end of the inter-rib connecting plate 8 connected with the second rib 52 is fixed compared with one end connected with the third rib 53, therefore, the inter-rib connecting plate 8 supports the second rib 52 and the third rib 53, so that the included angle between the third rib 53 and the connecting block 61 is increased and approaches 90 degrees, on one hand, the limiting part 621 of the wedge block 62 is prevented from abutting against the connecting block 61, so that the bending degree of the piezoelectric fiber driver 7 is prevented from being limited, on the other hand, the flexible skin is adhered and fixed on the outer sides of the third rib 53 and the second rib 52, the shape of the flexible skin mainly determines the aerodynamic shape of the wing, and the arrangement of the inter-rib connecting plate 8 can reduce the aerodynamic shape of the piezoelectric fiber driver 7 of the wing Influence.

When the piezoelectric fiber driver 7 of the secondary flexible segment B2 is electrically energized to bend and deform, the fourth rib 54 end of the secondary flexible segment B2 deflects further upward. Because the secondary flexible section B2 is positioned at the tail end and is subjected to a small bending moment, a large bending degree can be obtained under the action of the piezoelectric fiber driver 7.

The utility model discloses an effect of piezoelectric fiber driver 7 for changeover portion A and flexible section B1, B2 take place the linkage, with bending deformation from changeover portion A through multistage transmission to wing tip (the wing tip in this embodiment is fourth rib 54), thereby realize wing tip winglet 100's deflection, and the mechanism is simple, has characteristics such as nimble controllable, reversible and can warp repeatedly.

The utility model discloses a based on piezoelectric fiber driver 7 variable inclination winglet 100 mechanism structure light in weight, can bear great moment of flexure, and can be adapted to the little constraint condition of winglet 100 inner space well.

The utility model discloses an aircraft fuselage left and right sides's wing structure is the same. The inclined angle of the wingtip winglet 100 is increased during takeoff, so that the induced resistance can be reduced to the maximum extent, the aircraft can take off with smaller thrust, and meanwhile, the increase of the inclined angle enables the wingspan to be increased and the lifting surface of the wingtip winglet 100 to be increased, so that the aircraft can obtain larger lift force, and the oil consumption is reduced; when the aircraft is in cruise mode, the winglet 100 is returned to its cruise design position, optimizing the cruise drag characteristics.

The winglet 100 in this embodiment is composed of a transition section a and two flexible sections B1, B2, and in other embodiments, the number of the flexible sections may be increased or decreased according to the requirements such as deformation.

The above is only the preferred embodiment of the present invention, not limiting the scope of the present invention, all of which are under the concept of the present invention, the equivalent structure transformation made by the contents of the specification and the drawings is utilized, or the direct/indirect application in other related technical fields is included in the patent protection scope of the present invention.

Claims

1. A winglet with a variable inclination angle is arranged at the tail end of a wing body in the wingspan direction, and is characterized in that, the winglet comprising a first rib connected to the wing body, a fourth rib disposed at an end of the winglet, a second rib located between the first and fourth ribs, and a piezoelectric fiber driver, the piezoelectric fiber driver comprises a base steel sheet and a piezoelectric fiber sheet, the piezoelectric fiber driver is respectively connected between the first wing rib and the second wing rib, and between the second wing rib and the fourth wing rib, a transition section of the winglet being formed between the first and second ribs and a flexible section of the winglet being formed between the second and fourth ribs, the transition section is connected with the wing main body and the flexible section, main beams are arranged on the transition section and the wing main body, and the first wing rib and the second wing rib are fixedly connected with the main beams.

2. The variable camber winglet of claim 1, further comprising a third rib disposed between the second and fourth ribs, the piezoelectric fiber driver being coupled between the second and third ribs and between the third and fourth ribs, the flexible section comprising a primary flexible section and a secondary flexible section, the primary flexible section of the winglet being formed between the second and third ribs and the secondary flexible section of the winglet being formed between the third and fourth ribs, the primary flexible section being provided with inter-rib connection plates.

3. The variable pitch winglet of claim 2, wherein the inter-rib connecting plate is disposed below the piezoelectric fiber driver of the primary flexible section and has opposite ends hingedly connected to the second rib and the third rib, respectively.

4. The variable camber winglet of claim 2, further comprising a bracing mechanism, the bracing mechanism comprising a wedge block having a fulcrum portion and a rigid link having a fulcrum groove, the wedge block being mounted on each of the second and third ribs, the two piezoelectric fiber drivers of the transition section and the primary flexible section, and the two piezoelectric fiber drivers of the primary flexible section and the two piezoelectric fiber drivers of the secondary flexible section being fixedly connected by the link, the fulcrum portion abutting the fulcrum groove, the abutment forming a fulcrum about which the link and the wedge block can tilt.

5. The winglet of claim 4, wherein each of the second rib and the third rib has a through slot in the wingspan direction, the upper slot wall and the lower slot wall of the through slot are respectively provided with the wedge blocks, the connecting block passes through the through slot and is clamped between the upper wedge block and the lower wedge block, the upper surface and the lower surface of the connecting block are respectively recessed to form an arc-shaped fulcrum slot, and the fulcrum portions of the two wedge blocks are respectively abutted against the bottoms of the two fulcrum slots of the connecting block.

6. The variable angle winglet of claim 5, wherein the wedge block further comprises a stop portion for limiting the angle at which the connecting block is tilted relative to the wedge block.

7. The winglet of claim 4, wherein each of the connection blocks is recessed at opposite ends in the span direction to form a horizontally extending clamping groove for clamping a base steel sheet of the piezoelectric fiber driver, and the connection block is further provided with a pin hole communicating with the clamping groove for fixing the base steel sheet.

8. The winglet of claim 1, wherein the first rib defines a slot, and wherein an end of the base steel sheet of the transition section extends up and down through the slot to form a sliding pair against a catch of the first rib.

9. The variable rake winglet of claim 1, wherein the main spar uses an i-beam structure including an upper bead connecting upper sides of the first and second ribs, a lower bead connecting lower sides of the first and second ribs, and a stiffener connecting the upper and lower beads, the upper and lower beads being aligned in an up-down direction, the main spar being disposed proximate to the leading edge of the wing body in a chordwise direction perpendicular to the spanwise direction, the piezoelectric fiber drive of the transition section being disposed perpendicular to and rearward of the main spar; the flexible section adopts a flexible skin, and the transition section and the wing main body adopt conventional skins.

10. An aircraft comprising a variable rake winglet according to any one of claims 1 to 9.