A new type of deformable wing rib

Abstract

The invention discloses a novel deformable wing rib, which belongs to the field of structural design of deformable aircraft, and is characterized in that it comprises a front end connecting plate and a rear end connecting plate, wherein a flexible structure and a supporting guide beam are arranged between the front end connecting plate and the rear end connecting plate, wherein the flexible structure is a deformation region of the deformable wing rib, and the flexible structure produces uniform deformation; the outer sides of the front end connecting plate and the rear end connecting plate are respectively the web of the front beam of the wing and the web of the rear beam of the wing; the flexible structure is formed by extending a plurality of jujube-shaped unit cell structures in series, and the jujube-shaped unit cell structure is composed of two flexible plates; the front end connecting plate and the rear end connecting plate are respectively connected to the flexible plates at the front and rear ends of the flexible structure; the invention adopts the jujube-shaped unit cell structures in series to form a variable chord length wing rib structure that can be deformed in the chord direction, thereby realizing uniform change of the chord length of the wing and realizing uniform support of the flexible skin at the same time.

Description

Technical Field

[0001] The invention belongs to the field of variant aircraft structure design, and in particular relates to a deformable wing rib based on a jujube-shaped unit cell structure. Background Art

[0002] Morphing aircraft can change the shape of the aircraft structure in real time during flight, so that it can have the best aerodynamic performance when making different flight movements under different flight conditions. The variable chord length wing causes reasonable changes in aspect ratio and wing area through the change of wing chord length, so as to optimize the aircraft's lift-to-drag ratio, flight speed and maneuverability. During the wing deformation process, the flexible skin produces a large in-plane deformation, but at the same time it must have out-of-plane stiffness and bear a large aerodynamic load. In order to improve the out-of-plane load-bearing capacity, it is necessary to arrange longitudinal ribs along the span direction in the flexible skin to bear the out-of-plane aerodynamic load. During the skin deformation process, the spacing of the longitudinal ribs of the skin changes evenly, so the deformable wing ribs need to be well matched with the flexible skin to allow the skin to deform evenly. The current deformable wing ribs are difficult to achieve coordinated deformation with the skin, cannot achieve good matching with the flexible skin, and cannot provide good support for the flexible skin.

[0003] The present invention uses a jujube-shaped flexible single-cell structure to expand and connect into a deformable wing rib, which cooperates with the flexible skin. When the wing chordwise deforms, the matching connection between the deformable wing rib and the longitudinal ribs of the flexible skin also undergoes equal-spaced displacement, ensuring uniform support for the flexible skin. Summary of the invention

[0004] The present invention provides a deformable wing rib based on a jujube-shaped unit cell structure for a variant aircraft with a variable wing chord length. The wing rib can change its length uniformly along the chord direction so as to provide uniform connection and support for the flexible skin.

[0005] The present invention is achieved in that:

[0006] A novel deformable wing rib, the deformable wing rib comprises a front connecting plate and a rear connecting plate, a flexible structure and a supporting guide beam are between the front connecting plate and the rear connecting plate, the flexible structure is a deformation area of ​​the deformable wing rib, and the flexible structure produces uniform deformation; the outer sides of the front connecting plate and the rear connecting plate are the web of the wing front beam and the web of the wing rear beam respectively;

[0007] The front connecting plate and the rear connecting plate are equivalent to reinforcing plates, which strengthen the support plates of the first unit cell and the support plates of the last unit cell; the flexible structure is formed by a plurality of jujube-shaped unit cell structures extended in series, and the jujube-shaped unit cell structure is composed of two flexible plates; the flexible plates at the front and rear ends of the flexible structure are respectively connected to the front connecting plate and the rear connecting plate; the front connecting plate and the rear connecting plate are also equivalent to connecting plates, and the width of the front connecting plate and the rear connecting plate is wider than the flexible plate, and connecting holes are opened on both sides of the width to connect the first flexible plate of the flexible structure to the web of the front beam of the wing, and to connect the last flexible plate of the flexible structure to the web of the rear beam of the wing; the support guide beam passes through the flexible structure and the front and rear end connecting plates and is fixedly connected to the web of the front beam of the wing, and the rear end of the support guide beam overlaps the web of the rear beam of the wing, and passes through the web of the rear beam of the wing, so as to slide relatively;

[0008] The rear end of the support guide beam passes through the web of the wing rear beam and extends a certain distance to ensure that the rear end of the support guide beam will not fall out of the web of the rear beam when the flexible structure is deformed to the limit position, and to ensure that its end does not interfere with other structures in the wing.

[0009] Furthermore, the flexible board includes a middle support plate, curved plates at the upper and lower ends of the support plate, the curved plate is cut into a middle curved plate and side curved plates on both sides, and a crack stop hole is opened at the top of the cut; a guide hole is opened in the middle of the support plate; and the two ends of the flexible board are connection areas.

[0010] Furthermore, when the flexible board is formed into a jujube-shaped unit cell, the side curved plates and the middle curved plates of the flexible board are respectively bent in different directions perpendicular to the flexible board surface to set initial positions and the shapes are fixed by punching; the flexible board with fixed shape is matched with the corresponding side curved plates and the middle curved plates of the adjacent flexible board, and the 5 mm long connection area of ​​the contact edge is welded to form a jujube-shaped unit cell structure; a crack-stopping hole is punched at the root of the cut between the side curved plates and the middle curved plates on the flexible board to prevent stress concentration cracking at the root, and the diameter of the crack-stopping hole is selected to be three times the width of the cut.

[0011] Furthermore, the plurality of jujube-shaped unit cell structures are mutually extended in series to form a flexible structure; the two flexible plates at the front and rear ends of the flexible structure, the support plates thereof, the front and rear end connecting plates and the front and rear beam webs of the wing are riveted through connecting holes; the connecting areas of the upper and lower edges of each jujube-shaped unit cell constituting the flexible structure are also connected to the longitudinally arranged ribs on the flexible skin of the wing;

[0012] When the wing stretches or shortens in the chord direction, the spacing between the ribs of the flexible skin increases or decreases; at the same time, the flexible structure in the deformable wing rib will also be stretched or compressed, and the spacing between the jujube-shaped unit cell structures in the flexible structure will also increase or shorten equidistantly, and always cooperate with the ribs on the skin to ensure good support for the skin while deforming.

[0013] Furthermore, a guide hole is opened on the support plate on the flexible plate, and the guide hole is adapted to the support guide beam and slides on the support guide beam; the support guide beam plays a supporting role for the flexible structure; the cross-section of the guide beam is adapted to the shape of the guide hole; the support guide beam is fixed to the web of the front beam, and then the flexible structure is assembled to the support guide beam, the front end plate is connected to the web of the front beam, and the rear end plate is connected to the web of the front beam.

[0014] Furthermore, the support guide beam can also be used as a slide rail and arranged on the outside of the flexible structure; the slide rail type support guide beam includes a support guide slide rail, the support guide slide rail has a dovetail slide groove opened axially, a protruding dovetail structure is arranged on the flexible plate, the dovetail slide groove cooperates with the protruding dovetail structure on the flexible plate, the flexible plate can slide along the axis on the support guide slide rail, and at the same time, the support guide slide rail supports the flexible structure on the outside, playing the same role as the support guide beam.

[0015] The beneficial effects of the present invention compared with the prior art are:

[0016] The present invention adopts a jujube-shaped unit cell structure in series to form a variable-chord length wing rib structure that can be deformed in the chord direction, which can achieve uniform change in the chord length of the wing and achieve uniform support for the flexible skin. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic diagram of the deformable rib structure of the present invention;

[0018] Figure 2 This is a schematic diagram of the flexible board structure of the present invention:

[0019] Figure 3 It is a schematic diagram of the basic unit of the jujube-shaped unit cell structure of the present invention;

[0020] Figure 4 It is a schematic diagram of the flexible structure of the present invention;

[0021] Figure 5 This is a schematic diagram of the support method of the support guide beam of the present invention:

[0022] Figure 6 This is a schematic diagram of the supporting guide rail support method of the present invention:

[0023] Among them, 1-wing front beam web, 2-front end connecting plate, 3-flexible structure, 4-support guide beam, 5-rear end connecting plate, 6-wing rear beam web, 7-side curved plate, 8-middle curved plate, 9-support plate, 10-guide hole, 11-crack stop hole, 12-connecting area, 13-flexible plate, 14-support guide rail. DETAILED DESCRIPTION

[0024] In order to make the purpose, technical solution and effect of the present invention clearer and more specific, the present invention is further described in detail by enumerating examples below. It should be noted that the specific implementation described here is only used to explain the present invention and is not used to limit the present invention.

[0025] like Figures 1 to 5 As shown, the deformable wing rib structure of the present invention comprises a deformable wing rib including a front end connecting plate 2 and a rear end connecting plate 5, between which are a flexible structure 3 and a supporting guide beam 4, the flexible structure being the deformation area of ​​the deformable wing rib, and producing uniform deformation; the outer sides of the front end connecting plate 2 and the rear end connecting plate 5 are respectively a wing front beam web 1 and a wing rear beam web 6.

[0026] The deformation area of ​​the deformable rib is the flexible structure between the front and rear beams of the wing, and the flexible structure can produce uniform deformation. The flexible structure is formed by the serial expansion of the jujube-shaped single-cell structure. The front connecting plate 2 and the rear connecting plate 5 are respectively connected to the flexible plates at the front and rear ends of the flexible structure. The front and rear connecting plates are equivalent to reinforcing plates, which strengthen the support plates of the first single cell and the support plates of the last single cell. At the same time, the front and rear connecting plates are also equivalent to connecting plates. The width of the front and rear connecting plates is slightly wider than that of the flexible plates. Connecting holes are opened on both sides of the widening, and the first flexible plate is connected to the web plate 1 of the front beam of the wing and the last flexible plate is connected to the web plate 6 of the rear beam of the wing. The support guide beam 4 passes through the flexible structure and the front and rear connecting plates and is fixedly connected to the web plate 1 of the front beam of the wing. The rear end of the support guide beam 4 overlaps the web plate 6 of the rear beam of the wing, and passes through the web plate 6 of the rear beam of the wing, and can slide relatively. The rear end of the support guide beam 4 passes through the web of the rear beam and extends a certain distance to ensure that the rear end of the support guide beam will not fall out of the web of the rear beam when the flexible structure is deformed to the limit position, and to ensure that its end does not interfere with other structures in the wing.

[0027] A single jujube-shaped cell is composed of two pieces Figure 2 The flexible board shown in the figure is composed of 1, where 1 is a side bending board, 2 is a middle bending board, 3 is a support board, 4 is a guide hole, 5 is a crack stop hole, and 6 is a connection area. When the flexible board is used to form a jujube-shaped unit cell, the side bending board 7 and the middle bending board 8 of the flexible board 13 are bent in different directions perpendicular to the flexible board surface to the set initial position, and the shape is fixed by punching. The fixed-shape flexible board is matched with the corresponding side bending board 7 and middle bending board 8 of the adjacent flexible board, and the 5mm long connection area of ​​the contact edge is welded to form the following. Figure 3 The jujube-shaped unit cell structure shown in the figure. A crack-stopping hole 11 is punched at the root of the slit between the side curved plate 7 and the middle curved plate 8 on the flexible plate to prevent stress concentration cracking at the root, and the diameter of the crack-stopping hole is selected to be three times of the slit width.

[0028] like Figure 4 As shown, a plurality of jujube-shaped unit cell structures are mutually extended in series to form a flexible structure. The two flexible plates 13 at the front and rear ends of the flexible structure, the support plates thereof are riveted to the front and rear end connecting plates and the front and rear beam webs of the wing through connecting holes. The connection areas of the upper and lower edges of each jujube-shaped unit cell constituting the flexible structure are also connected to the longitudinally arranged ribs on the flexible skin of the wing at the same time. When the wing is elongated or shortened in the chord direction, the spacing between the ribs of the flexible skin increases or decreases. At the same time, the flexible structure in the deformable wing rib will also be stretched or compressed, and the spacing between the jujube-shaped unit cell structures in the flexible structure will also increase or shorten at equal distances from each other, and always cooperate with the ribs on the skin to ensure good support for the skin while deforming.

[0029] like Figure 5 As shown, the support plate on the flexible plate has a guide hole, which is adapted to the support guide beam and slides on the support guide beam. Therefore, the support guide beam can play a supporting role for the flexible structure. The cross section of the guide beam is adapted to the shape of the guide hole. The support guide beam is fixed to the web of the front beam, and then the flexible structure is assembled to the support guide beam, the front end plate is connected to the web of the front beam, and the rear end plate is connected to the web of the front beam.

[0030] If the airfoil height is relatively small, the flexible plate height will also be relatively small. In this case, the insertion method of the support guide beam can be as follows: Figure 6 In the manner shown, the support guide beam is arranged as a slide rail outside the flexible structure. The support guide slide rail has a dovetail-shaped slide groove along the axial direction, which cooperates with the dovetail-shaped structure protruding from the flexible plate. The flexible plate can slide along the axis on the support guide slide rail, and the support guide slide rail supports the flexible structure on the outside, playing the same role as the support guide beam.

[0031] The specific implementation modes of the present invention are further described below using specific data.

[0032] When the wing is subjected to aerodynamic loads, the load on the flexible skin is evenly transferred to the ribs through the flexible structure. When the wing is deformed in the chord direction, the spacing between the ribs on the skin changes evenly. The upper and lower edge connection areas of the jujube-shaped unit cell structure that constitutes the flexible structure are connected to the longitudinal ribs on the flexible skin to transfer the load. At the same time, when the wing is deformed in the chord direction, the drive arranged between the front and rear beams of the wing provides driving force to change the spacing between the front and rear beams.

[0033] In this example, the deformable wing is selected as the NACA0012 airfoil, and the initial chord length of the wing is selected as 1500mm. The wing can be deformed within a range of 300mm, and the maximum chord length of the wing when deformed to the extreme position is 1800mm. The front beam of the wing is arranged at 375mm from the leading edge of the wing, and the distance between the rear beam of the wing and the front beam changes with the length of the flexible structure. When the flexible structure is in the initial position, the chord length of the wing is 1500mm, and the distance between the rear beam of the wing and the front beam is 540mm. The distance between the rear beam of the wing and the trailing edge is 585mm. The web thickness of the front and rear beams of the wing is 3mm, and the thickness of the front and rear end connecting plates is also 2.5mm, so the length of the flexible structure in the initial position is 535mm.

[0034] The flexible structure is 165mm high and 40mm wide. The flexible structure of the deformable wing rib is located between the front and rear beams of the wing and is formed by 25 jujube-shaped cells extended in series. When the wing chord length is compressed to the shortest, the flexible structure is in the initial position and is 525mm long. The spacing between the single jujube-shaped cell structures is 21mm. When the wing chord length is extended to the longest, the flexible structure is 825mm long, and the spacing between the single jujube-shaped cell structures is 33mm. The support plate of the first jujube-shaped cell and the front connecting plate are screwed to the web of the front beam through the connecting hole, and the support plate of the last jujube-shaped cell and the rear connecting plate are riveted to the web of the rear beam through the connecting hole. The support guide beam passes through the middle guide hole of the flexible structure, and the front end passes through the front flexible plate of the flexible structure and is fixed to the front connecting plate and the web of the front beam. The support beam is 875mm long. When the wing chord length is deformed to the longest range, the end of the support beam extends 35mm from the web of the rear beam. When the wing chord length is deformed to the shortest range, the end of the support beam extends 335mm from the web of the rear beam, which is less than the 585mm distance between the rear beam and the trailing edge of the wing, and no interference occurs. The cross-sectional dimensions of the support beam are 5mm wide and 23mm high.

[0035] The flexible plate of the jujube-shaped single-cell structure is 165mm high and 40mm wide. The opening spacing range of the jujube-shaped single-cell structure is between 21mm and 33mm, so the one-way opening width of the middle curved plate and the side curved plate on a single flexible plate is between 10.5mm and 16.5mm. According to the deformation of the flexible plate, the thickness of the flexible plate is determined to be 2mm, the width of the side curved plate is 10mm, the width of the middle curved plate is 20mm, and the length of the two curved plates is 55mm. Therefore, the length of the slit on the flexible plate is 55mm, the width of the slit is 0.5mm, and the diameter of the crack stop hole at the end of the slit is 1.5mm. A guide hole is opened on the flexible plate for inserting the support guide beam. The shape of the guide hole is the same as the cross-section of the support guide beam, and the size is slightly larger than the cross-section size of the support guide beam. The flexible plates located at both ends of the flexible structure do not have a middle curved plate on the flexible plate, and the support plate has a connection hole connected to the front and rear end connecting plates.

[0036] The flexible structure is composed of a jujube-shaped unit cell structure that is extended in series. The initial opening distance of the flexible plate is 21mm. The middle curved plate and the side curved plate are unilaterally bent in different directions, and the end deflection is 10.5mm, which is half of the opening distance of the flexible plate. The deflection curves of the middle curved plate and the side curved plate when the end deflection is 10.5mm are used as the initial shapes of the middle curved plate and the side curved plate, and they are stamped and shaped. The flexible plate is then connected to the adjacent flexible plate that is also processed to the initial shape. When connected, the corresponding connection areas of the middle curved plates and the side curved plates on the two flexible plates fit together, and then are welded to form the following. Figure 3 The jujube-shaped unit cell structure shown in the figure is extended in series in the same way on this basis, and a flexible structure is gradually formed. The flexible plates at the front and rear ends of the flexible structure need to be connected to the webs of the front and rear beams of the wing, so there is no need for the middle bending plate to bend toward the front and rear beams of the wing. For the convenience of connection, the middle bending plate is removed from the flexible plates at both ends. The final flexible plate structure is shown in Figure 4 shown.

[0037] The above description is only a preferred embodiment of the present invention. It should be pointed out that a person skilled in the art can make several improvements without departing from the principle of the present invention, and these improvements should also be regarded as within the protection scope of the present invention.

Claims

1. A new type of deformable rib, It is characterized in that The deformable wing rib comprises a front connecting plate (2) and a rear connecting plate (5); a flexible structure (3) and a supporting guide beam (4) are located between the front connecting plate (2) and the rear connecting plate (5); the flexible structure is a deformation area of ​​the deformable wing rib, and the flexible structure produces uniform deformation; the outer sides of the front connecting plate (2) and the rear connecting plate (5) are respectively a wing front beam web (1) and a wing rear beam web (6); The front connecting plate (2) and the rear connecting plate (5) are equivalent to reinforcing plates, which reinforce the supporting plate of the first unit cell and the supporting plate of the last unit cell; The flexible structure (3) is formed by a plurality of jujube-shaped unit cell structures connected in series and extended, and the jujube-shaped unit cell structure is composed of two flexible plates (13); the flexible plates at the front and rear ends of the flexible structure are respectively connected to a front connecting plate (2) and a rear connecting plate (5); The front connecting plate (2) and the rear connecting plate (5) are also equivalent to connecting plates. The width of the front connecting plate (2) and the rear connecting plate (5) is wider than that of the flexible plate. Connecting holes are opened on both sides of the wider portion to connect the first flexible plate of the flexible structure (3) to the wing front beam web (1), and to connect the last flexible plate of the flexible structure (3) to the wing rear beam web (6); The support guide beam passes through the flexible structure and the front and rear end connecting plates to be fixedly connected to the wing front beam web (1), and the rear end of the support guide beam overlaps the wing rear beam web (6) and passes through the wing rear beam web (6) to slide relatively. The rear end of the support guide beam passes through the wing rear beam web (6) and extends a certain distance, ensuring that the rear end of the support guide beam will not fall out of the rear beam web when the flexible structure is deformed to the limit position, and ensuring that its end does not interfere with other structures in the wing.

2. A novel deformable rib according to claim 1, It is characterized in that The flexible plate comprises a middle support plate (9), curved plates at the upper and lower ends of the support plate (9), the curved plate (8) is cut into a middle curved plate (8) and side curved plates (7) at both sides, and a crack stop hole (11) is provided at the top of the cut; a guide hole (10) is provided in the middle of the support plate (9); and both ends of the flexible plate are connection areas (12).

3. According to the novel deformable rib of claim 2, It is characterized in that When the flexible plate (13) is formed into a jujube-shaped unit cell, the side curved plates (7) and the middle curved plates (8) of the flexible plate (13) are respectively bent in different directions perpendicular to the flexible plate surface to set initial positions, and the shapes are fixed by punching; the flexible plate with a fixed shape is matched with the corresponding side curved plates and the middle curved plates of the adjacent flexible plate, and the connection area with a length of 5 mm at the contact edge is welded to form a jujube-shaped unit cell structure; a crack-stopping hole is punched at the root of the slit between the side curved plates and the middle curved plates on the flexible plate to prevent cracking due to stress concentration at the root, and the diameter of the crack-stopping hole is selected to be three times the width of the slit.

4. According to the novel deformable rib of claim 1, It is characterized in that The multiple jujube-shaped unit cell structures are mutually extended in series to form a flexible structure; the two flexible plates at the front and rear ends of the flexible structure, the support plates thereof are riveted to the front and rear end connecting plates and the front and rear beam webs of the wing through connecting holes; the connecting areas of the upper and lower edges of each jujube-shaped unit cell constituting the flexible structure are also connected to the longitudinally arranged ribs on the flexible skin of the wing; When the wing stretches or shortens in the chord direction, the spacing between the ribs of the flexible skin increases or decreases; at the same time, the flexible structure in the deformable wing rib will also be stretched or compressed, and the spacing between the jujube-shaped unit cell structures in the flexible structure will also increase or shorten equidistantly, and always cooperate with the ribs on the skin to ensure good support for the skin while deforming.

5. According to the novel deformable rib of claim 1, It is characterized in that The support plate on the flexible plate is provided with a guide hole (10), the guide hole (10) is matched with the support guide beam (4), and slides on the support guide beam; the support guide beam plays a supporting role for the flexible structure; the cross section of the guide beam is matched with the shape of the guide hole; the support guide beam is fixed to the web of the front beam, and then the flexible structure is assembled to the support guide beam, the front end plate is connected to the web of the front beam, and the rear end plate is connected to the web of the front beam.

6. A novel deformable rib according to claim 1, It is characterized in that The support guide beam (4) can also be used as a slide rail and arranged on the outside of the flexible structure; the slide rail type support guide beam (4) includes a support guide slide rail (14), the support guide slide rail (14) has a dovetail-shaped slide groove along the axial direction, a protruding dovetail-shaped structure is arranged on the flexible plate, the dovetail-shaped slide groove cooperates with the protruding dovetail-shaped structure on the flexible plate, the flexible plate can slide along the axis on the support guide slide rail, and at the same time, the support guide slide rail supports the flexible structure on the outside, playing the same role as the support guide beam.

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