A ball-joint four-bar variable airfoil mechanism and a flexible variable leading-edge airfoil structure

Abstract

This invention discloses a ball-joint four-bar variable airfoil mechanism and a flexible variable leading-edge airfoil structure. The variable airfoil mechanism (2) of this invention includes a base (21), a first link (22), a second link (23), and a driving device. One end of the first link is hinged to the base via a ball joint, and the other end is hinged to the flexible leading-edge skin structure via a ball joint. The second link is a telescopic rod; one end is hinged to the base via a ball joint, and the other end is hinged to the flexible leading-edge skin structure via a ball joint. The base, the first link, the second link, and the flexible leading-edge skin structure together constitute a rigid-flexible coupled four-bar mechanism. The driving device is used to drive the variable airfoil mechanism to perform structural transformation actions, thereby driving the airfoil structure to change its leading-edge configuration. The variable airfoil mechanism and airfoil structure of this invention can achieve a wide variety of airfoil bending, twisting, and sweeping configuration transformations.

Description

Technical Field

[0001] This invention relates to an airfoil transformation mechanism, and more particularly to a ball-joint four-bar variable airfoil mechanism and a flexible variable leading-edge airfoil structural component. Background Technology

[0002] The wing is one of the most important components of an aircraft, mounted on the fuselage. Its primary function is to generate lift, contributing to good stability and controllability along with the tail. Additionally, munitions, equipment, and fuel tanks can be stored internally in the wing, while landing gear, engines, suspended missiles, external fuel tanks, and other external stores can be mounted on the wing. Generally, aerodynamic laws differ across subsonic, transonic, and supersonic speeds, and sometimes even exhibit completely opposite laws. Low-speed unmanned aerial vehicles (UAVs) often use straight wings with a high aspect ratio to achieve a higher lift coefficient. However, at transonic and supersonic speeds, straight wings generate significant wave drag, severely impacting flight performance. A recurring and difficult-to-overcome contradiction in traditional aircraft design is that increasing Mach number requires a large sweep angle and a low aspect ratio to reduce shock wave drag, but such wings result in lower lift, higher induced drag, and lower efficiency at subsonic speeds. From an aerodynamic perspective, to simultaneously meet the requirements of supersonic flight, subsonic cruise, and short takeoff and landing, it is best to allow the wing sweep angle to be variable, using different sweep angles to adapt to different flight conditions.

[0003] The current problem is that in existing aircraft, the angle of attack, area length, and sweep angle of the integral wing structure are all fixed. Only small-angle variable control surfaces are used to change the amount of lift, but this method provides limited lift. Similarly, in other fields, airfoil structures often cannot adapt to changes in the airfoil shape. When the working environment changes, they cannot adaptively change the airfoil shape, thus failing to maintain the airfoil structure in an optimal aerodynamic distribution. Summary of the Invention

[0004] The purpose of this invention is to provide a ball-joint four-bar variable airfoil mechanism and a flexible variable leading edge airfoil structure. This variable airfoil mechanism and airfoil structure can realize a wide variety of airfoil transformation configurations, thereby adjusting the airfoil configuration and angle of attack in a timely manner when the working environment changes, and optimizing the aerodynamic performance of the airfoil.

[0005] To achieve the above-mentioned technical objectives, the present invention adopts the following technical solution:

[0006] A ball-joint four-bar variable airfoil mechanism is provided, wherein the variable airfoil mechanism is disposed at the leading edge of the airfoil structure, and the variable airfoil mechanism includes a base, a first link, a second link, and a drive device;

[0007] The base is fixed to the main structure of the airfoil structure;

[0008] One end of the first link is hinged to the base via a ball joint, and the other end of the first link is hinged to the leading edge flexible skin structure via a ball joint.

[0009] The second link is a telescopic link. One end of the second link is hinged to the base via a ball joint, and the other end of the second link is hinged to the leading edge flexible skin structure via a ball joint.

[0010] The base, the first link, the second link, and the leading edge flexible skin structure together form a four-bar linkage. The driving device is used to drive the variable airfoil mechanism to perform structural transformation actions, thereby driving the airfoil structural component to change the configuration of the airfoil leading edge.

[0011] Furthermore, the first and second links are hinged and have rotational degrees of freedom.

[0012] Furthermore, the second link is a two-section telescopic rod, a three-section telescopic rod, or a four-section telescopic rod.

[0013] Furthermore, the first connecting rod is a straight rod, a two-section telescopic rod, a three-section telescopic rod, or a four-section telescopic rod.

[0014] Furthermore, the driving device includes a first actuator, a second actuator, and a third actuator;

[0015] The first actuator is used to drive the extension and retraction of the second link;

[0016] The second and third actuators respectively drive the second link to swing in two dimensions.

[0017] Furthermore, the airfoil structure is a wind turbine blade, a water turbine blade, a steam turbine blade, or a gas turbine blade.

[0018] A flexible variable leading edge airfoil structure is provided, wherein the airfoil structure is provided with a plurality of variable airfoil mechanisms as described above, and the plurality of variable airfoil mechanisms are evenly and discretely arranged along the spanwise direction of the airfoil structure.

[0019] Furthermore, the airfoil structure is a wind turbine blade, a water turbine blade, a steam turbine blade, or a gas turbine blade.

[0020] The variable airfoil mechanism of this invention is located at the leading edge of the airfoil structure and is used to implement configuration changes at the leading edge of the airfoil structure. Since the variable airfoil mechanism of this invention is constructed based on a ball-joint four-bar linkage, compared with the prior art, using the variable airfoil mechanism of this invention to achieve airfoil configuration changes not only changes the curvature of the airfoil perpendicular to the incoming flow direction, but also changes the torque of the airfoil perpendicular to the incoming flow direction, as well as the tilt angle of the airfoil relative to the incoming flow direction. This allows for a wide variety of airfoil configuration changes, enabling timely adjustment of the airfoil configuration and angle of attack when the working environment changes, optimizing the aerodynamic performance of the airfoil, and achieving optimal aerodynamic distribution. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the ball-joint four-bar variable airfoil mechanism of the present invention in an airfoil;

[0022] Figure 2 for Figure 1 An enlarged schematic diagram of the leading edge of the airfoil in the middle wing;

[0023] Figure 3 This is a schematic diagram of the variable airfoil mechanism of the present invention in an airfoil, wherein the second link is in the extended state;

[0024] Figure 4 This is a schematic diagram of the variable airfoil mechanism of the present invention arranged in the wing. Detailed Implementation

[0025] The present invention will be further illustrated below with specific embodiments:

[0026] See Figure 1 and Figure 3 This embodiment provides a ball-joint four-bar variable airfoil mechanism 2, which is located inside the aircraft wing 1, specifically at the leading edge of the airfoil of the wing 1. The function of the variable airfoil mechanism 2 is to change and adjust the configuration of the leading edge of the airfoil of the wing 1 in order to achieve the function of "optimizing aerodynamic performance, thereby improving flight efficiency and enhancing flight stability".

[0027] See Figure 2 The variable airfoil mechanism 2 in this embodiment includes a base 21, a first connecting rod 22, and a second connecting rod 23.

[0028] The base 21 is fixedly installed on the main body structure inside the wing 1, and can preferably be fixed to the web structure of the wing 1. Specifically, a vertical rib 11 is provided inside the wing 1, and the base 21 is fixedly installed together with the rib 11.

[0029] The base 21 has two hinge points, namely an upper hinge point and a lower hinge point. The upper hinge point is close to the upper surface of the wing 1, and the lower hinge point is close to the lower surface of the wing 1.

[0030] One end of the first link 22 is hinged to the base 21 via a ball joint, specifically to the upper hinge point of the base 21. The other end of the first link 22 is hinged to the leading edge flexible skin structure via a ball joint. The hinged part is the transition part of the leading edge flexible skin structure on one side of the upper surface of the wing 1.

[0031] The second link 23 is a telescopic rod. One end of the second link 23 is hinged to the base 21 via a ball joint, specifically to the lower hinge point of the base 21. The other end of the second link 23 is hinged to the leading edge flexible skin structure via a ball joint. The hinged part is the transition part of the leading edge flexible skin structure near the lower surface of the wing 1.

[0032] It should be noted that the previously mentioned leading-edge flexible skin structure refers to the flexible skin structure at the leading edge of the airfoil of wing 1.

[0033] It should be noted that the "transition section of the leading edge flexible skin structure" mentioned earlier refers to the transition section of wing 1 from the leading edge of the airfoil to the upper and lower surfaces.

[0034] In this embodiment, the second connecting rod 23 is a two-section telescopic rod. In other embodiments, other forms of telescopic rods, such as three-section telescopic rods or four-section telescopic rods, may also be used.

[0035] The first link 22 and the second link 23 are constrained by a spherical hinge, thus having rotational freedom.

[0036] In this embodiment, the base 21, the first link 22, the second link 23 in the variable airfoil mechanism 2 are combined with the leading edge flexible skin structure to form a rigid-flexible coupling four-bar linkage. By changing the structure of this four-bar linkage, the airfoil leading edge configuration of the wing 1 can be changed and adjusted, thereby achieving the effect of "optimizing the aerodynamic performance of the airfoil and achieving the optimal aerodynamic distribution".

[0037] To enable the four-bar linkage to change its structure, a drive device is also needed for the variable airfoil mechanism 2 to drive the leading edge of the wing 1 to change its configuration. It should be noted that "driving the variable airfoil mechanism 2 to perform structural change actions" includes "the structural change actions of the four-bar linkage itself" and "the extension and retraction of the second link 23".

[0038] In this embodiment, the driving device includes three hydraulic actuators, which are referred to as the first actuator, the second actuator, and the third actuator, respectively, for ease of description.

[0039] The first actuator is used to drive the extension and retraction of the second link 23, and it is installed based on both ends of the second link 23;

[0040] The second and third actuators are both mounted on the internal structure of the wing 1. These two hydraulic actuators drive the second link 23 to swing in two dimensions, respectively.

[0041] The aforementioned drive device is capable of performing two-way drive actions on the second link 23.

[0042] On the one hand, it drives the second link 23 to perform a telescopic movement.

[0043] On the other hand, the second link 23 is driven to perform a three-dimensional swinging motion based on the base 21, specifically based on its hinge connection point with the base 21.

[0044] In this way, the second link 23, as the active component, can drive the entire four-bar linkage to perform structural changes.

[0045] In other embodiments, the drive device may also employ other drive forms such as motor drive or piezoelectric drive.

[0046] It should be noted that the drive device used in the variable airfoil mechanism 2 of the present invention is not limited to a specific device. Those skilled in the art can design a specific drive device according to the functional requirements of the airfoil structure, and can adopt various existing design forms to meet various functional requirements.

[0047] Compared with the prior art, the variable airfoil mechanism 2 of this embodiment can not only change the curvature of the airfoil in the direction perpendicular to the incoming flow, but also change the twist of the airfoil in the direction perpendicular to the incoming flow, as well as the tilt angle of the airfoil relative to the incoming flow direction. In this way, a wide variety of airfoil transformation configurations can be achieved, thereby optimizing the aerodynamic performance of the airfoil and achieving the best aerodynamic distribution effect.

[0048] It should be noted that in other embodiments, the first link 22 can also be in the form of a telescopic rod, which can be a telescopic rod in the same form as the second link 23, and a corresponding drive device can be set for the telescopic action. In this way, more diverse configuration changes can be achieved.

[0049] See Figure 4The actual designed and constructed wing 1 incorporates multiple variable airfoil mechanisms 2, which are evenly and discretely arranged along the span of the wing 1. This allows for the control of the overall airfoil leading edge configuration of the wing 1. The specific number of variable airfoil mechanisms 2 in the wing 1 must be determined based on the requirements of the aircraft design.

[0050] It should be noted that the variable airfoil mechanism 2 of the present invention is not limited to use on the wing 1, but can also be applied to other airfoil structural components, such as wind turbine blades, water turbine blades, steam turbine blades, gas turbine blades, etc.

[0051] The above are merely preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Therefore, any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A ball-joint four-bar variable airfoil mechanism, wherein the variable airfoil mechanism (2) is disposed at the leading edge of the airfoil structure, characterized in that: The variable airfoil mechanism (2) includes a base (21), a first link (22), a second link (23), and a drive device; The base (21) is fixed to the main body structure of the airfoil structure; One end of the first link (22) is hinged to the base (21) via a ball joint, and the other end of the first link (22) is hinged to the leading edge flexible skin structure via a ball joint. The second link (23) is a telescopic rod. One end of the second link (23) is hinged to the base (21) through a ball joint, and the other end of the second link (23) is hinged to the front edge flexible skin structure through a ball joint. The base (21), the first link (22), the second link (23) and the leading edge flexible skin structure are combined to form a four-bar linkage. The driving device is used to drive the variable airfoil mechanism (2) to perform structural transformation actions, so as to drive the airfoil structural component to change the airfoil leading edge configuration. The first link and the second link form a hinged constraint with multiple degrees of freedom of rotation in space through a ball joint; The driving device includes a first actuator, a second actuator, and a third actuator; The first actuator is used to drive the extension and retraction of the second link (23); The second and third actuators respectively drive the second link (23) to swing in two dimensions, so as to collaboratively drive the airfoil leading edge of the airfoil structure to bend, twist and / or tilt angle relative to the incoming flow direction in three-dimensional spatial configuration transformation. The base (21) is mounted on a vertical rib (11) located inside the wing body.

2. The ball-joint four-bar linkage variable airfoil mechanism according to claim 1, characterized in that: The second link (23) is a two-section telescopic rod, a three-section telescopic rod, or a four-section telescopic rod.

3. The ball-joint four-bar variable airfoil mechanism according to claim 1, characterized in that: The first connecting rod (22) is a straight rod, a two-section telescopic rod, a three-section telescopic rod, or a four-section telescopic rod.

4. The ball-joint four-bar variable airfoil mechanism according to claim 1, characterized in that: The airfoil structure is a wind turbine blade, a water turbine blade, a steam turbine blade, or a gas turbine blade.

5. A flexible variable leading edge airfoil structural component, characterized in that: The airfoil structure is provided with a plurality of variable airfoil mechanisms (2) as described in any one of claims 1 to 3, and the plurality of variable airfoil mechanisms (2) are arranged uniformly and discretely along the spanwise direction of the airfoil structure.

6. The flexible variable leading edge airfoil structure according to claim 5, characterized in that: The airfoil structure is a wind turbine blade, a water turbine blade, a steam turbine blade, or a gas turbine blade.

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