WO2021128674A1

WO2021128674A1 - High-strength wing structure

Info

Publication number: WO2021128674A1
Application number: PCT/CN2020/087016
Authority: WO
Inventors: 杨思强
Original assignee: 南京祖航航空科技有限公司
Priority date: 2019-12-27
Filing date: 2020-04-26
Publication date: 2021-07-01
Also published as: CN211417574U

Abstract

A high-strength wing structure comprising a keel (1), a wing spar (2) and an arc-shaped cladding layer (3), wherein the keel (1) is longitudinally distributed, the wing spar (2) is transversely distributed, the arc-shaped cladding layer (3) is coated on the surface of the keel (1) and the wing spar (2) for enabling the keel and the wing spar to be stressed uniformly, both the keel (1) and the wing spar (2) are composite structures, and each composite structure comprises light wood (11) and carbon fiber cloth wrapped outside the light wood (11). Wings which are light in weight, high in strength, low in cost and suitable for industrial production are provided.

Description

A high-strength wing structure

Technical field

The utility model belongs to the field of unmanned aerial vehicles, in particular to a high-strength wing structure.

Background technique

The wing is an important part to realize the take-off of a fixed-wing UAV. However, the extension of the wing as a fixed-wing UAV is most likely to collide with the ground or objects and cause damage when the fixed-wing UAV takes off and landing.

The existing fixed-wing UAVs use a single material to make the wings, and the use of a single material cannot be balanced in terms of weight, strength and cost. It is not suitable for industrial production. Therefore, the wing structure of the fixed-wing UAV needs to be modified. To provide a fixed-wing UAV with a light weight, high strength and low cost wing at the same time.

technical problem

The purpose of the utility model is to provide a high-strength wing structure to solve the above-mentioned problems in the prior art.

Technical solutions

A high-strength wing structure includes: a longitudinally distributed keel, a transversely distributed spar, and an arc-shaped coating layer covering the surface of the keel and the spar for uniform stress. The keel and the wing There are at least three beams, and the keel and the spar are cross-fixedly connected to form a stressed structural frame, and a containment cavity is enclosed between the stressed structural frame and the arc-shaped coating layer.

Wherein, the keel and the spar are both composite structures, and the composite structure includes balsa wood and carbon fiber cloth wrapped on the outer side of the balsa wood.

In a further embodiment, the containment cavity is also filled with foam plastic, and the foam plastic is fixedly connected to the keel, the spar and the arc-shaped coating layer. The use of light-weight foam plastic can be used for the keel, the spar and the arc. The shaped cladding provides support.

In a further embodiment, the balsa wood, carbon fiber cloth, foam plastic, keel, spar and arc-shaped covering layer are fixed by resin adhesive. The use of resin glue can not only fix balsa wood, carbon fiber cloth, foam plastic, keel, spar and arc-shaped coating, but also fill gaps and provide support, and the weight is lower than that of screwing and other fixing methods.

In a further embodiment, the material of the arc-shaped coating layer is a PE heat shrinkable film. The use of PE heat-shrinkable film with super strong winding force and retraction can wrap the wing into a whole and further improve the stability of the wing.

In another embodiment, the material of the arc-shaped covering layer is carbon fiber cloth. The use of carbon fiber cloth as the arc-shaped covering layer increases the weight compared to the solution using PE heat shrinkable film, but it can provide stronger supporting force and make the wing more stable.

In another embodiment, the joint between the keel and the spar is provided with grooves that cooperate with each other, and the keel and the spar are fixedly connected by plugging. Using resin and foam to fix the keel and the spar, although the keel and the spar can be fixed together, the resin and foam cannot withstand the large force generated by collision or friction with the ground or objects. There is still a problem of easy misalignment at the connection.

In another embodiment, a carbon fiber cloth is attached to the joint between the keel and the spar. Although the continued use of carbon fiber cloth increases the weight of the drone, it increases the force area of the keel and the spar when the force is applied, and further reduces the force of the keel and the spar when the keel and spar are inserted. The chance of misalignment.

In a further embodiment, the keel includes a first keel, a second keel, and a third keel distributed from left to right, and the wing spar includes a first wing spar, a second wing spar, and a third keel distributed from top to bottom. Three-wing beam; the first keel and the third keel are deflected in the opposite direction along the central axis of the second keel, and the first and third wing spars are reversely deflected along the central axis of the second wing beam, forming a trapezoid-like structure with a predetermined overall twisting angle . Through the first keel and the third keel that are reversely deflected along the central axis of the second keel, the twisted structural frame composed of the first spar and the third spar is reversely deflected along the central axis of the second spar to support the arcing surface coating Layer, so that the pressure of the first keel when cutting the air can be distributed to the second keel and the third keel by the first wing spar, the second wing spar and the third wing spar, and the surface of the curved structural frame has no edges and corners. Will not cause damage to the arc surface coating

Beneficial effect

The utility model solves the problems of low strength using only balsa wood, heavy weight using only metal materials, and high cost of using only carbon fiber materials by wrapping carbon fiber cloth on cheap balsa wood. The high toughness of balsa wood supports the carbon fiber cloth. The high strength of carbon fiber cloth protects the balsa wood. In addition, the light wood and carbon fiber cloth are lighter than metal. The keel and spar are designed as a composite structure so that the wing has both light weight and strength. The characteristics of high and low cost, and the advantages of uniform and easy processing of balsa wood are used. It is easy to design and produce the required keel and spar. It is suitable for industrial production. The arc coating layer covers the surface of the keel and spar to make the keel The uniform force is formed on the whole with the spar so that the wing can obtain good stability, and the arc-shaped cladding layer can be used as the outer shell to design the appropriate keel and spar thickness to support the arc-shaped cladding layer to meet the aerodynamics The wing of the wing, through the force-bearing structural frame, not only provides a high-strength wing but also reserves a containing cavity to reduce the weight of the wing.

Description of the drawings

Figure 1 is a schematic partial cross-sectional view of the wing of the present invention.

Figure 2 is a schematic cross-sectional view of the composite structure of the present invention.

Fig. 3 is a schematic diagram of the first embodiment of the present invention.

Fig. 4 is a schematic diagram of the second embodiment of the present invention.

Fig. 5 is a schematic diagram of the third embodiment of the present invention.

Fig. 6 is a schematic diagram of a fourth embodiment of the present invention.

Fig. 7 is a schematic diagram of the fifth embodiment of the present invention.

The reference signs shown in FIGS. 1 to 7 are: keel 1, spar 2, arc-shaped covering layer 3, containment cavity 4, balsa wood 11, carbon fiber cloth 12, foam plastic 21, and resin 22.

Embodiments of the present invention

During the test flight of the fixed-wing UAV, the applicant found that the fixed-wing UAV will cause turbulence due to strong winds or uneven ground during take-off and landing. The fixed-wing UAV’s wings are most likely to collide with the ground or objects and cause damage. The UAV cannot take off. The wing is prone to damage due to external factors such as uneven ground and weather, and the existing wing uses a single material to make the wing itself. This is in the production of the wing. In order to obtain sufficient strength, we choose to use metal materials to produce wings. Although the metal materials are strong but also heavy, the wings on both sides of the drone are heavier, and the inertia generated by the slight bumps will be relatively high. The large inclination and ground contact caused the UAV to fail to take off, and the metal wings also had the problem of excessive labor intensity during assembly.

In the prior art, there are carbon fiber materials that are lighter than metal materials and have sufficient strength. However, this material is expensive. If only this material is used to manufacture the wing of a fixed-wing drone, the cost is too high and not suitable for industrial production. .

In order to solve the above problems, the applicant of the present utility model has developed a light-weight, low-cost, and high-strength wing structure.

A high-strength wing structure includes: keel 1, wing spar 2, arc-shaped covering layer 3, containment cavity 4, balsa wood 11, carbon fiber cloth 12, foam plastic 21, and resin 22.

Both the keel 1 and the spar 2 are composite structures. As shown in Figure 2, the composite structure includes: balsa wood 11 and carbon fiber cloth 12. The balsa wood 11 that is easy to process can be produced according to the needs when the material is uniform to produce the required keel 1 or wing. The shape of the beam 2, and then use the resin 22 to glue the carbon fiber cloth 12 on the surface of the balsa wood 11. Using the balsa wood 11, the lightest commodity in the world, as the main body of the composite structure can greatly reduce the keel 1 and the spar. 2 weight, and then wrap the carbon fiber cloth 12 with the advantages of high strength, low density and thin thickness on the outside of the balsa wood 11, which can protect and reinforce the balsa wood 11, and make the composite structure provide for the keel 1 and the spar 2. Sufficient supporting force solves the problem that the weight of only metal materials is too large and the cost of using only carbon fiber materials is too high.

After the keel 1 and the spar 2 form the frame of the wing, there is a containment cavity 4, which further reduces the weight of the wing. In order to make the wing conform to the aerodynamics, it can generate enough lift during the gliding process to support the drone. Therefore, the outer side of the keel 1 and the spar 2 is also covered with an arc-shaped coating layer 3. The arc-shaped coating layer 3 is used to cover the containment cavity 4 and connect the keel 1 and the spar 2 into a whole to form the wing .

In the production of wings, each wing has at least three keels 1 and spars 2. As shown in Figure 1, the advantages of balsa wood 11 are uniform and easy to process. The keels 1 at both ends are integrated into an arc-shaped plate. , The middle keel 1 is two arc-shaped plates that cooperate with each other, and the spar 2 is an arc-shaped plate that is fixedly connected to all the keels 1. The arc of the keel 1 and the spar 2 can be produced and designed according to the needs of use. The keel 1 and the wing The curvature of the beam 2 directly affects whether the appearance of the wing conforms to the aerodynamics after being covered with the arc-shaped covering layer 3. Before assembly, the carbon fiber cloth 12 is covered on the outside of the balsa wood 11 to increase the strength of the balsa wood 11 , The wing spar 2 and the keel 1 are cross-fixed and connected to each other by the resin 22 to form a stressed structural frame, and finally the arc-shaped coating layer 3 covers the containment cavity 4 and connects the keel 1 and the wing spar 2 into a whole to form the wing.

When the wing is working, the toughness of the balsa wood 11 provides support for the carbon fiber cloth 12. The high strength of the carbon fiber cloth 12 enhances the strength of the balsa wood 11. In addition, the keel 1 and the spar 2 are also covered with The arc-shaped cladding layer 3 is used to form a complete aerodynamic wing, and there is also a weight-reducing containment cavity 4 between the keel 1, the spar 2 and the arc-shaped cladding layer 3. The carbon fiber cloth 12 coated on the surface of the balsa wood 11 reduces the use area of the carbon fiber cloth 12 and reduces the production cost, so that the wing has the characteristics of light weight, high strength and low cost at the same time, and solves the problem of excessive weight of the wing. , When encountering turbulence, the fixed-wing UAV cannot be leveled in time due to its high inertia, resulting in damage to the wing, and the problem of excessive labor intensity when the wing is too heavy.

In flight, the cutting air force of the wing is transmitted from the arc-shaped coating layer 3 to the keel 1 and the spar 2, so that the arc-shaped coating layer 3 is coated on the surface of the keel 1 and the spar 2, and is received on the side of the wing. When force is applied, the arc-shaped coating layer 3 will be deformed. During the deformation of the arc-shaped coating layer 3, the force received is transferred to the unstressed part to achieve the effect of uniform force on the surface of the keel 1 and the spar 2.

In a further embodiment, in order to ensure that the keel 1, the spar 2 and the arc-shaped covering layer 3 are not misaligned and can be restored to working state after being pressed, the containment cavity 4 is also filled with foam plastic 21, and the foam The plastic 21 is fixedly connected to the keel 1, the spar 2 and the arc-shaped coating 3, and the foam plastic 21 is used to provide support for the keel 1, the spar 2 and the arc-shaped coating 3 to avoid the keel 1, the spar 2 and the arc. The covering layer 3 is misaligned after being pressed, and the elasticity of the foamed plastic 21 is used to make the keel 1, the spar 2 and the arc-shaped covering layer 3 still be able to resume their working state.

In a further embodiment, in order to improve the stability of the wing, PE heat-shrinkable film is used as the arc-shaped coating 3, and the super-strength winding force and retractability of the PE heat-shrinkable film are used to wrap the wing into a whole. Provides good stability, and uses the smooth surface of the PE heat shrinkable film to reduce the friction between the wing and the air.

In another embodiment, in order to further increase the strength and stability of the wing, the carbon fiber cloth 12 is used as the arc-shaped covering layer 3, the carbon fiber cloth 12 is used as the arc-shaped covering layer 3, and the PE heat shrinkable film is used. Compared with the increased weight, it can provide greater support and strength, and make the wing more stable.

In a further embodiment, after the carbon fiber cloth 12 is used as the arc-shaped covering layer 3, the outer side of the carbon fiber cloth 12 can also be covered with a PE heat shrinkable film to further use the smooth surface of the PE heat shrinkable film to reduce the friction between the wings and the air. .

In a further embodiment, in order to further reduce the weight of the wing, resin 22 is used to glue and fix the balsa wood 11, the carbon fiber cloth 12, the foam plastic 21, the keel 1, the spar 2 and the arc-shaped covering layer 3. Compared with the fixing method using metal bolts, the adhesive fixing method not only reduces the weight, but also can be filled with balsa wood 11, carbon fiber cloth 12, foam plastic 21, keel 1, spar 2 and arc-shaped coating 3 The gap between provides support.

In a further embodiment, as shown in FIG. 1, the keel 1 includes a first keel, a second keel, and a third keel distributed from left to right, and the spar 2 includes a first wing beam and a second keel distributed from top to bottom. The wing spar and the third wing spar; the first keel and the third keel are reversely deflected along the central axis of the second keel, and the first wing spar and the third wing spar are reversely deflected along the central axis of the second wing beam to form a predetermined overall twisting angle The trapezoid-like structure, the structural frame of the trapezoid-like structure has the advantages of lightweight structure and easy installation and maintenance, and the main stress points during the flight of the wing are on the first keel and the first wing spar, so that the first keel and the third keel are The reverse deflection of the keel along the central axis of the second keel means that there is an angle between the second keel and the third keel. When the first keel is under force, the first spar, the second spar and the third spar can be The force is transmitted obliquely to the second keel and the third keel. According to the principle of the longest hypotenuse of the triangle, the maximum supporting force provided by the maximum cross-sectional area of the oblique force on the second keel and the third keel is the same; The first wing spar and the third wing spar are deflected in the opposite direction along the center axis of the second wing spar so that there is an angle between the second wing spar and the third wing spar, and the force received by the first wing spar transmits the force obliquely. For the second spar and the third spar, the second spar and the third spar can provide the maximum support force, and a stable stressed structural frame that can provide support force is obtained through the deflection design.

In the first embodiment as shown in FIG. 3, the keel 1 and the spar 2 are fixedly connected by the resin 22 gluing method, which simplifies the production and assembly process, and is suitable for use in lightweight drones such as aircraft models.

In the second embodiment shown in FIG. 4, the joint of the keel 1 and the spar 2 is also provided with a groove that cooperates with each other, and the keel 1 and the spar 2 are fixedly connected by inserting, so that the keel 1 The connection with the wing spar 2 can be supported by a pure solid, which is stronger than the support of the resin 22, and the plugging method is a detachable connection, which is suitable for use in airplane models and aerial surveys, and facilitates the disassembly and carrying of the drone.

In the third embodiment shown in FIG. 5, the joint of the keel 1 and the spar 2 is also provided with a groove that cooperates with each other, and the keel 1 and the spar 2 are fixedly connected by inserting, and the keel 1 and the spar 2 are fixedly connected by inserting. The connection with the spar 2 is also filled with resin 22 to paste, which further improves the supporting force and the stability of the wing, and is suitable for use in aircraft models, aerial surveys and agricultural drones.

In the fourth embodiment shown in FIG. 6, the outer sides of the keel 1 and the spar 2 that were originally glued and fixed with resin 22 are also fixed and pasted with carbon fiber cloth 12. The high strength of the carbon fiber cloth 12 increases the machine. The weight of the wing also further improves the strength of the wing, enabling UAVs to be better used in agricultural UAVs.

In the fifth embodiment as shown in Fig. 7, the wing solution with the highest strength and the best stability is that the joint of the bone and the spar 2 is provided with cooperating grooves, the keel 1 and the spar 2 The connection between the keel 1 and the spar 2 is fixed and connected, and then the joint of the keel 1 and the spar 2 is filled with resin 22 for pasting. Finally, the outer side of the keel 1 and the spar 2 is fixed and pasted with a carbon fiber cloth 12, so that no one The machine can carry heavier weight.

Claims

A high-strength wing structure, which is characterized by comprising: longitudinally distributed keel (1), laterally distributed spar (2), and a coating on the surface of the keel and spar for uniform stress The arc-shaped coating layer (3), the keel (1) and the spar (2) are at least three, and the keel (1) and the spar (2) are cross-fixed and connected to form a stressed structural frame. A containment cavity (4) is enclosed between the force structure frame and the arc-shaped cladding layer;

Wherein, the keel (1) and the spar (2) are both composite structures, and the composite structure includes balsa wood (11) and carbon fiber cloth (12) wrapped on the outside of the balsa wood (11).
The high-strength wing structure according to claim 1, wherein the containing cavity (4) is also filled with foamed plastic (21), and the foamed plastic (21) is connected to the keel (1) and the spar. (2) Fixed connection with the arc-shaped coating layer (3).
The high-strength wing structure according to claim 2, wherein the balsa wood (11), carbon fiber cloth (12), foam plastic (21), keel (1), spar (2) and arc Resin (22) is used to glue and fix the shaped covering layers (3).
The high-strength wing structure according to claim 3, wherein the material of the arc-shaped coating layer (3) is PE heat shrinkable film.
The high-strength wing structure according to claim 3, characterized in that the material of the arc-shaped covering layer (3) is carbon fiber cloth (12).
The high-strength wing structure according to claim 3, characterized in that the joint of the keel (1) and the spar (2) is also provided with grooves that cooperate with each other, and the keel (1) and the wing The beams (2) are fixedly connected by inserting.
The high-strength wing structure according to claim 6, characterized in that, a carbon fiber cloth (12) is attached to the joint between the keel (1) and the spar (2).
The high-strength wing structure according to any one of claims 1 to 7, wherein the keel (1) comprises a first keel, a second keel and a third keel distributed from left to right, and the wing The beam (2) includes a first spar, a second spar, and a third spar distributed from top to bottom; the first keel and the third keel are reversely deflected along the central axis of the second keel, and the first spar and the third keel The spar deflects in the opposite direction along the central axis of the second spar to form a trapezoid-like structure with a predetermined overall twisting angle.