Composite laminated layup panel structure suitable for wing combined connection

Abstract

A composite laminated layup panel structure suitable for wing combined connection, comprising a main box section skin (100) and a plurality of stiffeners (200) which are integrally cured and formed. The main box section skin is sequentially provided with recesses (300) at a front edge and a rear edge, forming a front recessed edge (110) for overlapping with a leading edge skin (400) and a rear recessed edge (120) for overlapping with a trailing edge skin. A front spar stiffener (600) configured to be connected to a front spar web (500) is fixedly arranged at the bottom of a transition region between the front recessed edge (110) and a main box section skin main body. A rear spar stiffener (700) configured to be connected to a rear spar web is fixedly provided at the bottom of a transition region between the rear recessed edge (120) and the main box section skin main body. The panel structure simplifies connection forms of panels and related structures, reducing the number of parts, improving assembly efficiency, and also facilitating disassembly and replacement maintenance during aircraft use and maintenance.

Description

A composite material plywood structure suitable for wing assembly connections Technical Field

[0001] This invention relates to the field of aerospace structural design, and in particular to a composite material composite lay-up panel structure suitable for wing assembly connections. Background Technology

[0002] To reduce weight and improve structural load-bearing efficiency, modern aircraft structures commonly use composite materials to manufacture wing panel structures. Aircraft wings are generally box-shaped structures with aerodynamic conformation and a hollow interior. Except for certain single-use special-purpose aircraft, conventional aircraft wings typically include components such as a main box section, leading edge, and trailing edge, considering assembly processes and the maintenance and replacement requirements for long-term use. The main box section includes upper and lower panels, a front sparsity, a rear sparsity, and wing ribs. To improve structural rigidity, reinforcing ribs are usually installed between the upper and lower panels. To ensure connection strength while facilitating the assembly and disassembly of the leading and trailing edges and maintaining a smooth aerodynamic shape, the main box section panels form a relatively complex connection relationship with adjacent structures.

[0003] In existing technologies, the main box section panels and wing spars of small and medium-sized aircraft are connected by permanent fasteners, and the joint connecting the wing and fuselage is generally located at the root of the wing spars. The panel extends outwards from the main box section by a certain width and is connected to the leading edge structure by detachable fasteners. As shown in Figure 1, one connection method involves connecting the main box section panel b to the leading edge skin c via a strip plate a. The main box section uses a C-section beam e for connection, and the main box section panel b extends outwards, transitioning to the leading edge skin c via strip plate a. The gaps at the skin joints are filled with sealant to create a smooth aerodynamic profile. This design requires three rows of fasteners, used to connect the main box section panel b to the wing spars, the main box section panel b to the strip plate, and the strip plate to the leading edge skin. However, due to different stress conditions, the skin of the main box section wall panel b is generally thicker than the leading edge skin c (usually 2 to 3 times thicker). Therefore, the strip a needs to form a step to compensate for the thickness difference between the skins on both sides of the main box section wall panel b, thus ensuring a smooth aerodynamic shape. This steep step feature limits the material selection for the strip, generally requiring machining of slender metal materials. The above connection method has a relatively complex structure, a large number of parts, and a large assembly workload, which to some extent limits large-scale mass production.

[0004] As shown in Figure 2, another connection method is through an I-beam f, with the beam flange f1 extending to both sides, connecting the skin on one side of the main box section b and the skin on the front edge side, respectively. This connection method omits the plate connection, reducing one row of fasteners. However, to compensate for the thickness difference between the main box section wall panel b and the front edge skin c, a shim d is required at the mating surface between the I-beam and the front edge skin, resulting in a large number of parts. Because the I-beam needs to mate with the skin with the airfoil surface, a closed angle g is formed between one of its flanges and the web, which makes machining and demolding more difficult, and also increases the manufacturing cost of the beam structure. Summary of the Invention

[0005] In view of the shortcomings of the prior art described above, the technical problem to be solved by the present invention is to provide a composite material composite plywood structure suitable for wing assembly connection, so as to simplify the connection form between the components, reduce the number of parts, improve assembly efficiency, and facilitate disassembly and maintenance during aircraft use.

[0006] This invention proposes a composite material plywood structure suitable for wing assembly connections, comprising an integrally cured main box skin and multiple reinforcing ribs. The main box skin has recesses at its front and rear edges, forming a front recessed edge for overlapping the front edge skin and a rear recessed edge for overlapping the rear edge skin. A front spar reinforcing rib for connecting the front wing spars web is fixed at the bottom of the transition area between the front recessed edge and the main box skin body. A rear spar reinforcing rib for connecting the rear wing spars web is fixed at the bottom of the transition area between the rear recessed edge and the main box skin body.

[0007] Preferably, the slope of the depression is 30° to 60°.

[0008] Preferably, the depth of the front recessed edge is equal to the thickness of the front edge skin; and the depth of the rear recessed edge is equal to the thickness of the rear edge skin.

[0009] Preferably, the main box segment skin includes an outer panel ply and a main skin core layer, with the outer panel ply covering the top of the main skin core layer; the reinforcing rib includes a first ply, with a plurality of first plies covering the bottom of the main skin core layer; the front beam reinforcing rib includes a first ply and a second ply, with the second ply adhering to the bottom of the front edge of the outer panel ply and the adjacent first ply; the rear beam reinforcing rib includes a first ply and a third ply, with the third ply adhering to the bottom of the rear edge of the outer panel ply and the adjacent first ply, to form a wall panel ply assembly.

[0010] Preferably, adjacent first plies form a U-shaped ply.

[0011] Preferably, both the second and third plies are arranged in an L-shape.

[0012] Preferably, the transverse edge of the second ply is attached to the bottom of the front edge of the outer panel ply, and the transverse edge of the second ply is of the same thickness as the front edge of the outer panel ply; the longitudinal edge of the second ply is attached to the adjacent first ply, and the longitudinal edge of the second ply is of the same thickness as the adjacent first ply.

[0013] Preferably, the transverse edge of the third ply is attached to the bottom of the rear edge of the outer panel ply, and the transverse edge of the third ply is of the same thickness as the rear edge of the outer panel ply; the longitudinal edge of the third ply is attached to the adjacent first ply, and the longitudinal edge of the third ply is of the same thickness as the adjacent first ply.

[0014] Preferably, the wall panel ply assembly includes at least a first section, a second section, a third section, and a fourth section, which are sequentially spliced ​​together from the front edge to the rear edge; wherein, a sloped layer drop zone is provided between adjacent sections of the second section, the third section, and the fourth section, so that the ply thickness of the second section, the third section, and the fourth section decreases step by step.

[0015] Preferably, cavities are formed at the root between the second ply and the adjacent first ply, between the third ply and the adjacent first ply, and between the adjacent first ply, and the cavities are filled with a filling material.

[0016] As described above, the composite material plywood structure for wing assembly connections disclosed in this invention has the following advantages:

[0017] This invention features stepped recesses on the front and rear edges of the main box segment skin, forming a front recessed edge and a rear recessed edge. This allows the front edge skin to be directly overlapped with the front recessed edge, and the rear edge skin to be directly overlapped with the rear recessed edge. This avoids conventional connection methods based on complex shapes using plates or gaskets, reduces the number of parts, simplifies the connection structure, and improves assembly and maintenance efficiency.

[0018] This invention provides sufficient support for the front and rear recessed edges by fixing a front beam stiffener at the bottom of the transition area between the front recessed edge and the main body of the main body of the box segment skin, and a rear beam stiffener at the bottom of the transition area between the rear recessed edge and the main body of the main body of the box segment skin. This also compensates for the difference in thickness between the front and rear recessed edges and the main body of the box segment skin, effectively improving the support stiffness of the front and rear recessed edges, and simplifying the connection between the main body of the box segment skin and the wing beam structure.

[0019] This invention divides the prefabricated wall panel ply into multiple sections that can be spliced ​​together. Each section is spliced ​​together in the form of a prefabricated body. The ply design of each section takes into account the overall structure having a unified ply sequence and a complete ply reduction transition. This achieves the overall geometric features while coordinating the ply relationships within the material to ensure the mechanical properties of the parts, and at the same time improves the material utilization rate and the load-bearing efficiency of the structure. Attached Figure Description

[0020] Figure 1 is a schematic diagram of the first configuration in the prior art;

[0021] Figure 2 is a schematic diagram of the second configuration in the prior art;

[0022] Figure 3 is a three-dimensional schematic diagram of a composite material composite plywood structure suitable for wing assembly connection according to an embodiment of the present invention;

[0023] Figure 4 is a bottom view of Figure 3;

[0024] Figure 5 is a cross-sectional view AA of Figure 3;

[0025] Figure 6 is a magnified view (I) of a portion of Figure 5;

[0026] Figure 7 is a magnified view (II) of a portion of Figure 5;

[0027] Figure 8 is an assembly diagram of a composite material plywood structure suitable for wing assembly connection according to an embodiment of the present invention;

[0028] Figure 9 is a layup schematic diagram of a composite material composite layup wall panel structure suitable for wing assembly connection according to an embodiment of the present invention;

[0029] Figure 10 is a magnified view of a portion of the first section of Figure 9;

[0030] Figure 11 is a partial enlarged view of the second section of Figure 9;

[0031] Figure 12 is a magnified view of a portion of the third section of Figure 9;

[0032] Figure 13 is a magnified view of a portion of the fourth section of Figure 9;

[0033] Figure 14 is an exploded view of a composite material plywood structure suitable for wing assembly connection according to an embodiment of the present invention;

[0034] Figure 15 is a schematic diagram of the wall panel layup of a composite material composite layup wall panel structure suitable for wing assembly connection according to an embodiment of the present invention;

[0035] Figure 16 is a cross-sectional view of the ply transition in Figure 15 (BB);

[0036] Figure 17 is a view from direction C of Figure 16.

[0037] Explanation of reference numerals in the attached drawings: a) Strip plate; b) Wall panel; c) Front edge skin; d) Gasket; e) C-section beam; f) I-beam; f1) Beam flange; g) Closed angle; 100) Main box section skin; 110) Front recessed edge; 120) Rear recessed edge; 130) Outer panel ply; 140) Main skin core layer; 200) Reinforcing rib; 210) First ply; 220) Filler; 300) Recess; 400) Front edge skin; 500) Front wing beam web; 600) Front beam reinforcing rib; 610) Second ply; 700) Rear beam reinforcing rib; 710) Third ply; 800) Wall panel ply assembly; 810) First zone; 820) Second zone; 830) Third zone; 840) Fourth zone; 841) Depletion zone. Detailed Implementation

[0038] The following specific embodiments illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification.

[0039] It should be understood that the structures, proportions, sizes, etc., illustrated in the accompanying drawings of this specification are merely for illustrative purposes to aid those skilled in the art and are not intended to limit the scope of the invention. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in proportions, or adjustments to size, without affecting the effectiveness and purpose of the invention, should still fall within the scope of the technical content disclosed in this invention. Furthermore, the terms such as "upper," "lower," "left," "right," and "middle" used in this specification are merely for clarity and are not intended to limit the scope of the invention. Changes or adjustments to their relative relationships, without substantially altering the technical content, should also be considered within the scope of the invention.

[0040] Figures 1-8 illustrate an embodiment of a composite material plywood structure suitable for wing assembly connections, comprising an integrally cured main body skin 100 and multiple reinforcing ribs 200. The main body skin 100 has recesses 300 with a preferred, but not limited to, slope range of 30° to 60° at its front and rear edges; in this embodiment, the slope is preferably 45°. These recesses 300 are generally stepped to achieve thickness reduction, forming a front recessed edge 110 for overlapping the front edge skin 400 and a rear recessed edge 120 for overlapping the rear edge skin (not shown). The depth of the front recessed edge 110 is comparable to the thickness of the front edge skin 400, and the depth of the rear recessed edge 120 is comparable to the thickness of the rear edge skin. A front beam reinforcing rib 600 for connecting the front wing beam web 500 is fixed at the bottom of the transition area between the front recessed edge 110 and the main body of the main box segment skin 100. A rear beam reinforcing rib 700 for connecting the rear wing beam web (not shown in the figure) is fixed at the bottom of the transition area between the rear recessed edge 120 and the main body of the main box segment skin. The mating surfaces of the front beam reinforcing rib 600 and the front wing beam web 500, and the rear beam reinforcing rib 700 and the rear wing beam web are set as planes. Reinforcing ribs 200 are fixed to the bottom of the main box segment skin 100 and are evenly distributed between the front beam reinforcing ribs 600 and the rear beam reinforcing ribs 700. The reinforcing ribs 200, the front beam reinforcing ribs 600, and the rear beam reinforcing ribs 700 are all arranged along the span direction, extending from one end of the main box segment skin to the other end.

[0041] When installing the wing, the leading edge skin 400 is overlapped with the leading recessed edge 110, and the trailing edge skin is overlapped with the trailing recessed edge 120, and fixed with detachable fasteners to form a smooth aerodynamic surface for the entire wing. Due to the recess 300, a small gap is formed between the end of the leading edge skin 400 and the leading recessed edge 110. This gap is approximately equal to the thickness of the leading edge skin 400, and the gap is filled with a filler, including but not limited to sealant, to ensure a smooth and flat aerodynamic surface for the entire wing. Similarly, the gap formed between the trailing edge skin and the trailing recessed edge is not described here. The beam stiffener 600 is attached to the front wing spars web 500, and the rear wing stiffener 700 is attached to the rear wing spars web, and fixed with permanent fasteners, including but not limited to rivets. In this embodiment, the leading edge skin and trailing edge skin are directly overlapped with the main box section skin 100, avoiding the use of indirect connecting parts such as gaskets or stepped plates, thus simplifying the overall structure.

[0042] Further, as shown in Figures 6-8, the depth of the recess 300 is equal to the thickness of the front edge skin 400 and the rear edge skin. In this embodiment, the depth of the recess 300, the thickness of the main box section skin 100, the thickness of the front beam reinforcing rib 600, and the thickness of the rear beam reinforcing rib 700 are all preferably 0.8mm to 6mm, and the sum of the depth of the recess 300 and the thickness of the front beam reinforcing rib 600, and the sum of the depth of the recess 300 and the thickness of the rear beam reinforcing rib 700 are both equal to the thickness of the main box section skin 100. Taking the overlap of the front edge skin 400 as an example, the depth of the recess 300 is 2mm (equal to the thickness of the front edge skin). According to the strength criterion, the thickness of the main box section skin 100 is preferably 5mm, and the thickness of the front beam reinforcing rib 600 is preferably 3mm. The method used for the overlap of the rear edge skin and the front edge skin is the same, and will not be described again here.

[0043] In one embodiment, as shown in Figures 9-14, the main skin segment 100 includes an outer panel ply 130 and a main skin core layer 140. The main skin core layer 140 serves as the main ply, with the outer panel ply 130 covering its top. The outer panel ply 130 has recesses 300 at its front and rear edges to form recessed edges for overlapping the front and rear skin layers. The reinforcing ribs 200 include first ply layers 210, with multiple first ply layers 210 covering the bottom of the main skin core layer 140, providing sufficient support to the main skin core layer 100. The front beam stiffener 600 includes a first ply 210 and a second ply 610, with the second ply 610 adhering to the bottom of the front edge of the outer panel ply 130 and the adjacent first ply 210. The rear beam stiffener 700 includes a first ply 210 and a third ply 710, with the third ply 710 adhering to the bottom of the rear edge of the outer panel ply and the adjacent first ply 210, providing support for the outer panel ply 130 and the main skin core layer 140. The outer panel ply 130, the main skin core layer 140, each of the first ply 210, and the second ply 610 together form the wall panel ply assembly 800.

[0044] Furthermore, adjacent first plies 210 form a U-shaped ply, while the second and third plies 610 are both L-shaped. The transverse edge of the second ply 610 is attached to the bottom of the front edge of the outer panel ply, and the transverse edge of the second ply 610 is of the same thickness as the front edge of the outer panel ply, forming a symmetrical auxiliary layer. The longitudinal edge (i.e., the web surface) of the second ply 610 is attached to the adjacent first ply 210, and the longitudinal edge of the second ply is of the same thickness as the adjacent first ply 210. The transverse edge of the third ply 710 is attached to the bottom of the rear edge of the outer panel ply, and the transverse edge of the third ply 710 is of the same thickness as the rear edge of the outer panel ply. The longitudinal edge of the third ply 710 is attached to the adjacent first ply 210, and the longitudinal edge of the third ply 710 is of the same thickness as the adjacent first ply 210, forming a symmetrical auxiliary layer. In this process, the transverse edges of the second ply 610 and the third ply 710 form support and cover for the edge recessed area at the bonding surface, ensuring compensation for the thickness and height difference in this area, while simultaneously forming a smooth inner surface in the bonding area. The bonding of the third ply with the first ply and the second ply with the first ply provides sufficient support stiffness for the front and rear edges of the outer panel ply, and also serves to connect with the web of the wing beam, maximizing material utilization.

[0045] In one embodiment, as shown in Figures 10-13, the roots of the first ply 210, the second ply 610, and the third ply 710 are provided with rounded corners. The roots of the second ply 610 and the adjacent first ply 210, the third ply 710 and the adjacent first ply 210, and the adjacent first ply 210 are all formed with cavities by reverse rounded corners. The cavities are filled with a filler 220 that is the same as the material of the main skin core layer. The filler 220 includes, but is not limited to, twist strips, to maintain the continuity and integrity of the main skin core layer material and to provide effective support for the rounded corner areas of the first ply 210, the second ply 610, and the third ply 710.

[0046] In one embodiment, as shown in Figures 9-17, the panel ply assembly 800 includes at least a first section 810, a second section 820, a third section 830, and a fourth section 840. The first section 810, the second section 820, the third section 830, and the fourth section 840 are sequentially spliced ​​from the front edge to the rear edge, and each section has a different thickness variation according to its own stress characteristics. Among them, a sloped layer-dropping area 841 is provided between adjacent sections of the second section 820, the third section 830, and the fourth section 840, so that the ply thickness of the second section 820, the third section 830, and the fourth section 840 decreases step by step, as shown in Figure 17. The surface of the panel ply in the layer-dropping area 841 forms a gentle slope. The first section 810 consists of an outer panel ply 130, a main skin core layer 140, a second ply 610, and a first ply 210; the second section 820 and the third section 830 both consist of an outer panel ply 130, a main skin core layer 140, and a first ply 210; the fourth section 840 consists of an outer panel ply 130, a main skin core layer 140, a third ply 710, and a first ply 210. Each section can be prefabricated according to the corresponding ply layers, and then these prefabricated structures can be combined and cured in one go to form a complete wall panel structure. It should be noted that the outer panel ply 130, the main skin core layer 140, the second ply 610, the first ply 210, and the third ply 710 all contain missing layers, which are concentrated between the third section 830 and the fourth section 840.

[0047] Specifically, as shown in Figure 16, along the span direction, the outer panel ply number 130 is preferably 8, the main skin core layer ply number 140 is 24, and the first ply number 210 is 8, for a total of 40 ply areas. The ply areas at each location are coordinated via the ply reduction zone 841 to form a uniform transition zone. Through ply reduction transition, the outer panel ply number 130 is reduced to 6, the main skin core layer ply number 140 is reduced from 24 to 12, and the first ply number 210 is reduced from 8 to 6. Through a unified ply sequence and a complete ply reduction transition, the overall geometric characteristics are achieved while ensuring the coordination of the ply relationships within the material, thus guaranteeing the mechanical properties of the panel.

[0048] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in the present invention should still be covered by the claims of the present invention.

Claims

1. A composite material plywood structure suitable for wing assembly connections, characterized in that, The device includes an integrally cured main box segment skin (100) and multiple reinforcing ribs (200). The main box segment skin (100) has recesses (300) at its front and rear edges, forming a front recessed edge (110) for overlapping with the front edge skin (400) and a rear recessed edge (120) for overlapping with the rear edge skin. A front beam reinforcing rib (600) for connecting to the front wing beam web (500) is fixed at the bottom of the transition area between the front recessed edge (110) and the main box segment skin body. A rear beam reinforcing rib (700) for connecting to the rear wing beam web is fixed at the bottom of the transition area between the rear recessed edge (120) and the main box segment skin body.

2. The composite material plywood structure suitable for wing assembly connections according to claim 1, characterized in that, The slope of the depression (300) is 30° to 60°.

3. The composite material plywood structure suitable for wing assembly connections according to claim 2, characterized in that, The depth of the recess (300) is equal to the thickness of the leading edge skin (400) and the trailing edge skin.

4. The composite material plywood structure suitable for wing assembly connections according to claim 1, characterized in that, The main box segment skin (100) includes an outer panel ply (130) and a main skin core layer (140), the outer panel ply (130) covering the top of the main skin core layer (140); the reinforcing rib (200) includes a first ply (210), a plurality of first plies (210) covering the bottom of the main skin core layer (140); the front beam reinforcing rib (600) includes a first ply (210) and a second ply (610), the second ply (610) being attached to the bottom of the front edge of the outer panel ply and the adjacent first ply (210); the rear beam reinforcing rib (700) includes a first ply (210) and a third ply (710), the third ply (710) being attached to the bottom of the rear edge of the outer panel ply and the adjacent first ply (210) to form a wall panel ply assembly (800).

5. The composite material plywood structure suitable for wing assembly connections according to claim 4, characterized in that, The adjacent first ply (210) form a U-shaped ply.

6. The composite material plywood structure suitable for wing assembly connections according to claim 4 or 5, characterized in that, The second ply (610) and the third ply (710) are both arranged in an L-shape.

7. The composite material plywood structure suitable for wing assembly connections according to claim 6, characterized in that, The transverse edge of the second ply (610) is attached to the bottom of the front edge of the outer panel ply, and the transverse edge of the second ply (610) is the same thickness as the front edge of the outer panel ply; the longitudinal edge of the second ply (610) is attached to the adjacent first ply (210), and the longitudinal edge of the second ply is the same thickness as the adjacent first ply (210).

8. The composite material plywood structure suitable for wing assembly connections according to claim 7, characterized in that, The transverse edge of the third ply (710) is attached to the bottom of the rear edge of the outer panel ply, and the transverse edge of the third ply (710) is the same thickness as the rear edge of the outer panel ply; the longitudinal edge of the third ply (710) is attached to the adjacent first ply (210), and the longitudinal edge of the third ply (710) is the same thickness as the adjacent first ply (210).

9. The composite material plywood structure suitable for wing assembly connections according to claim 4, characterized in that, The wall panel ply assembly (800) includes at least a first section (810), a second section (820), a third section (830), and a fourth section (840), wherein the first section (810), the second section (820), the third section (830), and the fourth section (840) are sequentially spliced ​​from the front edge to the rear edge; wherein, a layer-dropping area (841) with a slope is provided between adjacent sections of the second section (820), the third section (830), and the fourth section (840), so that the ply thickness of the second section (820), the third section (830), and the fourth section (840) decreases step by step.

10. The composite material plywood structure suitable for wing assembly connections according to any one of claims 4-9, characterized in that, Cavities are formed at the root of the second ply (610) and the adjacent first ply (210), the third ply (710) and the adjacent first ply (210), and the adjacent first ply (210), and the cavities are filled with filler (220).

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