Wing structure capable of being folded and rapidly unfolded in chordwise direction

Abstract

The invention discloses a chordwise folding and rapid unfolding wing structure, and relates to the technical field of aircraft design, the chordwise folding and unfolding wing structure comprises a chordwise folding and unfolding wing section, the chordwise folding and unfolding wing section is divided into a plurality of wing sections along the chordwise direction, the division surfaces of two adjacent wing sections are planes, the separation planes on two adjacent flanges are provided with grooves, and the grooves are connected with the chordwise folding and unfolding wing section. Buffer gaskets and strong magnets are arranged in the grooves, and every two adjacent wing sections are connected through a film hinge; and a flow deflector is arranged above a connecting gap between every two adjacent flanges. According to the wing structure capable of being folded and rapidly unfolded in the chordwise direction, the wing structure can be divided into a plurality of wing sections capable of rotating around the dividing lines of the lower surface in the chordwise direction, so that the wing fully utilizes the annular storage size, and the limitation of the diameter of a cylinder on the chord length and the area of the wing can be broken through; the adjacent wing sections are connected through thin film hinges, so that the flying resistance is reduced; automatic positioning and locking between the adjacent wing sections are achieved through attraction force of the permanent magnets, the structure is simple, and reliability is high.

Description

Technical Field

[0001] This invention relates to the field of aircraft design technology, and in particular to a chordally folding and rapidly deploying wing structure. Background Technology

[0002] Foldable-wing drones possess foldable and deployable wings, allowing them to be stored in a stowage tube when folded, thus reducing transport volume. Currently, the wings of foldable-wing drones are generally fixed along their chord length, while the launch tube is typically cylindrical. Therefore, the chord length of the wing is strictly limited by the size of the launch tube, generally requiring a chord length smaller than the tube diameter. This leads to two problems: firstly, the smaller chord length limits the wing's Reynolds number, resulting in lower lift-to-drag ratio; secondly, the limited wing area affects the drone's maximum takeoff weight, resulting in weaker load-bearing capacity. Currently, most foldable-wing drones increase wing area through spanwise folding, but this still fails to fully utilize the circumferential space of the launch tube. Finding a new foldable wing structure that can overcome the limitations of the launch tube diameter, fully utilize circumferential space, and has a simple and reliable folding and unfolding process has become a key challenge in the design of foldable-wing drones. Summary of the Invention

[0003] The purpose of this invention is to provide a wing structure that can fold and unfold rapidly in the chord direction, solve the problems mentioned in the background art, make full use of the circumferential storage size, and break through the limitation of the cylinder diameter on the wing chord length and area.

[0004] To achieve the above objectives, the present invention provides a chordally folding and rapidly deploying wing structure, including a chordally folding wing section, which is divided into several wing segments along the chord direction. The dividing surfaces of two adjacent wing segments are both planes. Grooves are provided in the separating planes on two adjacent wing edges. Buffer pads and strong magnets are provided in the grooves. Two adjacent wing segments are connected by a thin film hinge. A guide vane is installed above the connection gap between two adjacent flanges.

[0005] Preferably, among the several wing segments, the wing segment closest to one-third of the chord line is the main load-bearing wing segment, and the root of the main load-bearing wing segment is fixedly connected to the wing; the remaining wing segments are V-shaped wing segments, and the root of the V-shaped wing segments is not fixedly connected to the wing.

[0006] Preferably, the total number of main load-bearing airfoil sections and V-shaped airfoil sections is set to 3 to 5.

[0007] Preferably, the groove includes a first groove and several second grooves. The strong magnet is fixedly disposed in the second groove, and the buffer pad is fixedly disposed in the first groove. The inner surface of the buffer pad is flush with the outer surface of the strong magnet, and the outer surface of the buffer pad is flush with the dividing surface.

[0008] Preferably, the cushioning pad is made of polystyrene foam, polyurethane foam, or polyethylene foam.

[0009] Preferably, two sets of strong magnets are provided between every two adjacent wing segments. The two sets of strong magnets are fixed in the same position on the two separating planes, and the magnetic properties of the two sets of strong magnets are opposite at the ends that are close to each other.

[0010] Preferably, multiple membrane hinges are provided and distributed along the spanwise direction on the lower surface of adjacent wing segments. The main materials of the membrane hinges are polypropylene, polyester film, nylon fabric, and tensile reinforcing fiber material along the tangential direction.

[0011] Preferably, the shape of the guide vane is consistent with the geometry of the wing, and the length of the guide vane is the same as the span of the wing section. The width of the guide vane is set to 5mm to 50mm, and the thickness of the guide vane is set to 0.2mm to 1.0mm.

[0012] Preferably, along the width direction, the leading edge of the guide vane is bonded to the upper surface of the trailing edge of the airfoil, the trailing edge of the guide vane is suspended, and both the leading and trailing edges of the guide vane have a gently sloping structure.

[0013] Therefore, the present invention employs the above-mentioned chordally folding and rapidly deploying wing structure, which has the following beneficial effects: (1) The wing is divided into multiple wing segments that can rotate around the dividing line of the lower surface along the chord direction, so that when the wing is stored in the tube, the chord line is divided into multiple segments around the center of the cross section, thereby making full use of the circumferential storage size, breaking through the limitation of the launch tube diameter on the wing chord length, and effectively increasing the chord length and wing area.

[0014] (2) Adjacent wing sections are connected by a membrane hinge, which can realize the rotation of the wing section around the dividing line, and eliminates the complex structure of the traditional mechanical hinge, saving structural mass and reducing flight drag.

[0015] (3) After the UAV is deployed, it uses the magnetic attraction of permanent magnets to achieve automatic positioning and locking, eliminating the need for springs and locking mechanisms in traditional folding structures, simplifying the structure, reducing the difficulty of folding and unfolding, and using buffer pads to protect the strong magnets and avoid collisions between wing sections that could damage the magnet structure.

[0016] (4) During flight, the torque generated by aerodynamic force will press the wing sections together more tightly, preventing the wing sections from separating under the action of aerodynamic force, and improving structural stability and reliability.

[0017] (5) Use guide vanes to cover the steps or gaps on the upper surface of the airfoil caused by process precision or docking error, thereby reducing the additional drag caused by airfoil segmentation.

[0018] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the overall structure of an embodiment of a chordally folding and rapidly deploying wing structure according to the present invention; Figure 2 This is a structural component diagram of a wing structure that allows for chordal folding and rapid deployment according to the present invention. Figure 3 This is a schematic diagram of the main load-bearing wing section and the wing-shaped section of a chordally folding and rapidly deploying wing structure according to the present invention. Figure 4 This is an assembly diagram of a wing segment, magnet, and buffer pad for a chordally folding and rapidly deploying wing structure according to the present invention. Figure 5 This is a schematic diagram of a thin-film hinge for a chordally folding and rapidly deploying wing structure according to the present invention; Figure 6 This is a schematic diagram of the air deflector in the folded state of a wing structure that allows for chordal folding and rapid deployment according to the present invention. Figure 7 This is a schematic diagram of the air deflector in the deployed state of a chordally folding and rapidly deploying wing structure according to the present invention; Figure 8 This is a schematic diagram of the internal storage and transportation state of a UAV with a chordally folding and rapidly unfolding wing structure according to the present invention. Figure 9 This is a schematic diagram of the unfolded state of a UAV after exiting the tube, which is a chordally folding and rapidly unfolding wing structure according to the present invention. Figure 10 This is a schematic diagram of the wing section of the chordally folding and rapidly deploying wing structure of the present invention under aerodynamic load in an automatically clamped state. Reference numerals: 1. Chord-shaped folding airfoil section; 2. Membrane hinge; 3. Strong magnet; 4. Buffer pad; 5. Guide vane; 101. Main load-bearing airfoil section; 102. V-shaped airfoil section; 103. Groove; 1031. Groove II; 1032. Groove I. Detailed Implementation

[0020] The technical solution of the present invention will be further described below with reference to the accompanying drawings and embodiments.

[0021] Unless otherwise defined, the technical or scientific terms used in this invention shall have the ordinary meaning understood by one of ordinary skill in the art to which this invention pertains. The terms "first," "second," and similar terms used in this invention do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Terms such as "comprising" or "including" mean that the element or object preceding the word encompasses the elements or objects listed following the word and their equivalents, without excluding other elements or objects. Terms such as "connected" or "linked" are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. Terms such as "upper," "lower," "left," and "right" are used only to indicate relative positional relationships; when the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0022] Example Please see Figure 1-10 This invention provides a chordally folding and rapidly deployable wing structure, including a chordally folding wing section 1. The chordally folding wing section 1 is divided into several wing segments along the chord direction. Among these segments, the segment closest to one-third of the chord line is the main load-bearing wing segment 101, which has high strength and stiffness. The root of the main load-bearing wing segment 101 is fixedly connected to the wing, enabling it to transfer wing shear force and bending torsional moment to the fuselage. The remaining wing segments are V-shaped wing segments 102, with relatively lower strength and stiffness, mainly used to maintain the wing shape. The root of the V-shaped wing segments 102 is not fixedly connected to the wing, and their load-bearing capacity is relatively weak. Figure 3 As shown, the total number of main load-bearing wing section 101 and wing section 102 is set to 3 to 5 sections, and the specific number is determined according to the specific situation of the UAV.

[0023] The dividing surfaces of two adjacent wing segments are both planes, such as... Figure 4 As shown, grooves 103 are formed in the separation planes of two adjacent flanges. A buffer pad 4 and a strong magnet 3 are disposed within each groove 103. Grooves 103 include a first groove 1032 and several second grooves 1031. The second grooves 1031 are deeper and used to firmly fix the magnets, while the first grooves 1032 are shallower and used to fix the buffer pad 4. The buffer pad 4 is made of polystyrene foam, polyurethane foam, or polyethylene foam. The inner surface of the buffer pad 4 is flush with the outer surface of the strong magnet 3, and the outer surface of the buffer pad 4 is flush with the separation plane. The buffer pad 4 effectively buffers the impact force during flange segment docking and protects the magnet structure.

[0024] Two sets of strong magnets 3 are installed between every two adjacent wing segments. The two sets of strong magnets 3 are fixed to the two separation planes by adhesive and are in the same relative position, thereby improving the positioning accuracy of the wing segment docking. The ends of the two sets of strong magnets 3 that are close to each other have opposite magnetism. Each set is equipped with multiple strong magnets 3. The strong magnets 3 are neodymium iron boron magnets and are mainly used for positioning and fixing adjacent wing segments.

[0025] like Figure 5 As shown, adjacent airfoil segments are connected by membrane hinges 2. Multiple membrane hinges 2 are provided and distributed along the spanwise direction. The front and rear parts are respectively bonded to the lower surface of the adjacent airfoil segments, while the upper surfaces are not connected, allowing the airfoil segments to rotate freely within a 180° range around the dividing line of the lower surface. The main materials of the membrane hinges 2 are polypropylene, polyester film, nylon fabric, etc., with tensile reinforcing fiber material added internally along the chord direction. This gives the membrane hinges 2 both flexibility and strength, resulting in high toughness, good durability, and light weight.

[0026] like Figure 6 and Figure 7 As shown, guide vanes 5 are installed above the joint gap between two adjacent wing edges. These guide vanes 5 are mainly used for wing shaping after the wing sections are joined, and their materials include carbon fiber, metal, and polyurethane film. The shape of the guide vanes 5 is consistent with the geometry of the wing, and the length of the guide vanes 5 is the same as the span of the wing section. The width of the guide vanes 5 is set to 5mm–50mm, and the thickness is set to 0.2mm–1.0mm, with the specific width and thickness determined according to the scale of the UAV. Along the width direction, the leading edge of the guide vanes 5 is bonded to the upper surface of the trailing edge of the wing section, while the trailing edge of the guide vanes 5 is suspended. Both the leading and trailing edges of the guide vanes 5 are polished to form a gently sloping structure, thereby preventing airflow separation and reducing wind resistance.

[0027] The specific working method of this invention is as follows: (1) such as Figure 8 As shown, when the UAV is stored in the tube, the wings are in an open state. The upper surface of the chord-folded wing section 1 is separated, and the lower surface is bonded by the thin film hinge 2. This storage method makes the wing chord length no longer strictly limited by the diameter of the launch tube, and can make full use of the circumferential space inside the launch tube. At the same time, due to the limitation of the tube wall, although the wing sections are attracted by the strong magnet 3, they will not dock.

[0028] (2) For example Figure 9 As shown, after the UAV exits the tube, the chordally folded wing segment 1 is attracted by the strong magnet 3, and the adjacent wing segments rotate around the thin film hinge 2 on the lower surface to complete the docking and fixation. During the docking process, the buffer pad 4 can effectively buffer the impact force between the wing segments during docking, protecting the structure of the wing segments and the strong magnet 3 from damage.

[0029] (3) such as Figure 10As shown, during flight, the aerodynamic force on each wing segment is upward. The non-main load-bearing wing segment 101 transmits the aerodynamic force to the main load-bearing wing segment 101 through the separation surface between the wing segments. At this time, the membrane hinge 2 is under tension, and the adjacent wing segments are in a compressed state.

[0030] (4) Due to the influence of processing technology and magnet positioning accuracy, gaps and steps may exist after adjacent airfoil sections are docked. The guide vane 5 can cover the gaps and steps to avoid local separation of airflow, thereby reducing aerodynamic losses.

[0031] (5) When retracting the wings after the flight, simply bend the wing section downwards to overcome the magnetic attraction and separate the adjacent wing sections. The operation is simple and reliable.

[0032] Therefore, the present invention adopts the above-mentioned chordally folding and rapidly deploying wing structure, which can be divided into multiple wing segments that can rotate around the lower surface dividing line along the chord, thereby making full use of the circumferential storage size of the wing and breaking through the limitation of the cylinder diameter on the wing chord length and area; adjacent wing segments are connected by thin film hinges, which can eliminate the complex hinge structure and reduce drag during flight; the attraction force of permanent magnets is used to realize the automatic positioning and locking between adjacent wing segments, and the torque brought by aerodynamic force is used to press the wing segments together, eliminating the need for springs and locking mechanisms, resulting in a simple structure and high reliability; the guide vanes are used to cover the steps or gaps on the upper surface of adjacent wing segments, thereby reducing the aerodynamic performance loss caused by wing segment division.

[0033] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the technical solutions of the present invention, and these modifications or equivalent substitutions cannot cause the modified technical solutions to deviate from the spirit and scope of the technical solutions of the present invention.

Claims

1. A wing structure that folds and deploys rapidly in the chord direction, characterized in that: It includes a chordally folded wing section, which is divided into several wing sections along the chord direction. The dividing surfaces of two adjacent wing sections are both planes. Grooves are provided in the separation planes on two adjacent wing edges. Buffer pads and strong magnets are placed in the grooves. Two adjacent wing sections are connected by a thin film hinge. A guide vane is installed above the connection gap between two adjacent flanges.

2. The wing structure with chordal folding and rapid deployment according to claim 1, characterized in that: Of the several wing segments, the segment closest to one-third of the chord line is the main load-bearing wing segment, and the root of the main load-bearing wing segment is fixedly connected to the wing; the remaining wing segments are V-shaped wing segments, and the root of the V-shaped wing segments is not fixedly connected to the wing.

3. The wing structure with chordal folding and rapid deployment according to claim 2, characterized in that: The total number of main load-bearing airfoil sections and V-shaped airfoil sections is set to 3 to 5.

4. The wing structure with chordal folding and rapid deployment according to claim 3, characterized in that: The groove includes a first groove and several second grooves. A strong magnet is fixedly installed in the second groove, and a buffer pad is fixedly installed in the first groove. The inner surface of the buffer pad is flush with the outer surface of the strong magnet, and the outer surface of the buffer pad is flush with the dividing surface.

5. The wing structure with chordal folding and rapid deployment according to claim 4, characterized in that: The cushioning pad is made of polystyrene foam, polyurethane foam, or polyethylene foam.

6. The wing structure with chordal folding and rapid deployment according to claim 5, characterized in that: Two sets of strong magnets are installed between each pair of adjacent wing sections. The two sets of strong magnets are fixed in the same position on the two separate planes, and the magnetic properties of the two sets of strong magnets are opposite at the ends that are close to each other.

7. The wing structure with chordal folding and rapid deployment according to claim 6, characterized in that: Multiple membrane hinges are provided and distributed along the spanwise direction on the lower surface of adjacent airfoils. The main materials of the membrane hinges are polypropylene, polyester film, nylon fabric and tensile reinforcing fiber material along the tangential direction.

8. The wing structure with chordal folding and rapid deployment according to claim 7, characterized in that: The shape of the guide vane is consistent with the geometry of the wing, and the length of the guide vane is the same as the span of the wing section. The width of the guide vane is set to 5mm to 50mm, and the thickness of the guide vane is set to 0.2mm to 1.0mm.

9. The wing structure with chordal folding and rapid deployment according to claim 8, characterized in that: Along the width direction, the leading edge of the guide vane is bonded to the upper surface of the trailing edge of the airfoil, the trailing edge of the guide vane is suspended, and both the leading and trailing edges of the guide vane have a gently sloping structure.

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