Blade locking device for unmanned aerial vehicle

Abstract

The invention provides a paddle anti-loosening device for an unmanned aerial vehicle. The paddle anti-loosening device comprises an unmanned aerial vehicle body, four vehicle arms, four motor assemblies, four paddle structures and a plurality of locking mechanisms. The four vehicle arms are evenly distributed on the unmanned aerial vehicle body, the motor assemblies are arranged at the ends, away from the unmanned aerial vehicle body, of the vehicle arms, and an outer rotor shell of one motor assembly is connected with one paddle structure through a plurality of locking mechanisms. The locking mechanism comprises a first anti-loosening structure, a fixing bolt and a buffering assembly, the fixing bolt penetrates through the first anti-loosening structure and an installation plate of the paddle structure and then is connected with an outer rotor shell of the motor assembly, and the buffering assembly is arranged on the lower end face of the first anti-loosening structure. According to the paddle anti-loosening device for the unmanned aerial vehicle, the problems that due to the fact that a paddle fixing structure in the related technology is improper in design, the surface of a paddle made of carbon fiber, wood or plastic is prone to being damaged, the structural integrity of the paddle is affected, and the anti-loosening effect is prone to losing efficacy are solved.

Description

Technical Field

[0001] The invention belongs to the technical field of unmanned aerial vehicles, and in particular relates to a blade loosening prevention device for unmanned aerial vehicles. Background Art

[0002] The propeller blades of a drone are key components for generating lift and propulsion, and are usually made of lightweight materials such as carbon fiber or composite materials. The design of the propeller blades directly affects the flight performance, stability, and efficiency of the drone. Firmly fixing the propeller blades can prevent the propeller blades from loosening due to vibration or collision during flight, thereby avoiding potential flight accidents.

[0003] The propeller blades of drones currently on the market are usually fixed with screws. However, the commonly used anti-loosening measure - screw glue, may fail in complex environments such as high temperature or oil pollution, resulting in a weakened protective effect. In addition, due to improper design of the blade fixing structure in related technologies, it is easy to cause damage to the surface of the carbon fiber, wood or plastic blades, which not only affects the structural integrity of the blades, but also easily leads to the failure of the anti-loosening effect, and then causes the risk of the blades loosening during flight. The accumulation of the above problems may cause the performance of the drone to decline, or even serious damage accidents. Therefore, it is crucial to improve the blade fixing and anti-loosening mechanism to ensure the safe operation and long-term use of the drone. Summary of the invention

[0004] In view of this, the present invention aims to solve one of the related technical problems at least to a certain extent.

[0005] To achieve the above object, the technical solution of the present invention is achieved as follows:

[0006] A propeller blade anti-loosening device for a drone, comprising a drone body, four arms, four motor assemblies, four propeller blade structures and a plurality of locking mechanisms;

[0007] The four arms are evenly distributed on the UAV body, the motor assembly is arranged at the end of the arm away from the UAV body, and the outer rotor housing of one motor assembly is connected to one blade structure through a plurality of locking mechanisms;

[0008] The locking mechanism comprises a first anti-loosening structure, a fixing bolt and a buffer assembly, wherein the fixing bolt passes through the first anti-loosening structure and the mounting plate of the blade structure and is connected to the outer rotor housing of the motor assembly, and the buffer assembly is arranged on the lower end surface of the first anti-loosening structure;

[0009] The first anti-loosening structure includes a first gasket, a plurality of first teeth and a plurality of locking plates. The plurality of first teeth are evenly arranged circumferentially on the outer end surface of the first gasket. The plurality of locking plates are evenly arranged circumferentially on the upper end surface of the first gasket. The mounting plate of the blade structure is provided with one or more locking holes that can cooperate with the first teeth. The locking plates can limit and fix the countersunk head of the bolt or the outer surface of the nut. Both the locking plates and the first teeth can be bent. The buffer assembly is arranged on the lower end surface of the first gasket.

[0010] Furthermore, the locking mechanism also includes a second anti-loosening structure, a plurality of wedge blocks are evenly arranged circumferentially on the lower end surface of the first gasket, the second anti-loosening structure includes a second gasket and a plurality of second teeth, the plurality of second teeth are evenly arranged circumferentially on the outer end surface of the second gasket, the upper end surface of the second gasket is provided with a plurality of limiting grooves that can cooperate with the wedge blocks, the mounting plate of the blade structure is provided with a first notch that can place the second gasket, and the inner wall of the first notch cooperates with the second tooth piece through the first tooth-shaped groove.

[0011] Furthermore, the locking mechanism also includes a third anti-loosening structure, which includes a third gasket, a rubber sleeve, a plurality of elastic tightening mechanisms and a plurality of third teeth. A second slot capable of accommodating the third gasket is provided at the bottom of the first slot, and an inner wall of the second slot cooperates with the third teeth through a second tooth-shaped groove. A plurality of third teeth are evenly arranged on the outer end face of the third gasket. The third gasket is provided with a circular hole capable of accommodating the rubber sleeve. A plurality of elastic tightening mechanisms are evenly arranged on the inner side of the circular hole. One end of the elastic tightening mechanism is connected to the inner wall of the circular hole, and the other end of the elastic tightening mechanism is arranged in a channel for installing a fixing bolt. When the fixing bolt is installed, the elastic tightening mechanism squeezes the bottom of the rubber sleeve so that the top of the rubber sleeve presses the lower end face of the second gasket.

[0012] Furthermore, the elastic tightening mechanism includes a guide rod, a return spring and a tightening block, one end of the guide rod is connected to the inner wall of the circular hole, the outer end of the guide rod is slidably matched with the tightening block, the return spring is arranged on the guide rod, one end of the return spring is against the tightening block, the other end of the return spring is against the bottom of the rubber sleeve, and the end of the tightening block is provided with an inclined surface, and the inclined surface is arranged in the channel where the fixing bolt is installed.

[0013] Furthermore, the first gasket is provided with a plurality of square holes for placing the locking plates, and the plurality of square holes are evenly arranged on the circumference of the first gasket.

[0014] Furthermore, the number of the locking plates and the number of the square holes are both 4.

[0015] Furthermore, the buffer component is an annular rubber ring.

[0016] Further, the outer rotor housing of a motor assembly is connected to a blade structure through 4 of the locking mechanisms.

[0017] Compared with the prior art, the blade anti-loosening device for an unmanned aerial vehicle of the present invention has the following advantages:

[0018] 1. A plurality of first teeth uniformly distributed on the outer circumference of the first gasket cooperate with the locking holes on the blade mounting plate to form a direct mechanical interlocking structure. When the blade is vibrated, the engagement between the first teeth and the locking holes can effectively inhibit the relative rotation between the blade and the motor assembly, preventing loosening of the bolts caused by circumferential shear force. The bendable locking piece above the first gasket wraps and fixes the outer surface of the countersunk head of the bolt or the nut, and generates a continuous pressing force by the elastic deformation of the locking piece. This elastic limit can not only offset the attenuation of the bolt pre-tightening force caused by vibration, but also directly limit the rotational freedom of the bolt through physical blockage. The annular rubber ring at the lower end of the first gasket serves as a buffer component, which can absorb the energy generated by the high-frequency vibration of the motor during the flight of the unmanned aerial vehicle and reduce the vibration amplitude transmitted to the fixing bolts. By reducing the dynamic load of the bolts, the loosening caused by fatigue is delayed. Both the locking piece and the first teeth are designed as bendable structures, allowing local elastic deformation when subjected to vibration or impact, avoiding stress concentration or structural fracture caused by excessive rigidity, and improving the adaptability of the device to complex working conditions.

[0019] 2. A plurality of wedge-shaped blocks at the lower end of the first gasket and the limiting grooves at the upper end of the second gasket form an inclined surface locking structure. The second teeth on the outer side of the second gasket engage with the first tooth-shaped grooves on the inner wall of the first notch of the mounting plate to form a second anti-rotation barrier. Even if the cooperation between the first teeth of the first anti-loosening structure and the locking holes fails, the second teeth can still prevent the relative movement between the blade and the outer rotor housing of the motor assembly through rigid engagement. The second anti-loosening structure transmits the load of the first anti-loosening structure to the first notch of the mounting plate through the second gasket, expanding the force-bearing contact area and avoiding stress concentration on a single component (such as the first gasket or the bolt). This hierarchical design significantly improves the anti-fatigue performance of the overall structure.

[0020] 3. The rubber sleeve is squeezed by the elastic tightening mechanism when the fixing bolt is installed, generating axial preload compensation. When the bolt loosens slightly due to vibration or temperature change, the elastic recovery force of the rubber sleeve can automatically fill the gap, continuously compressing the second gasket and the third gasket to prevent the preload from attenuating. The third tooth piece on the outside of the third gasket engages with the second tooth-shaped groove on the inner wall of the second notch to form a third anti-rotation barrier. Even if the first and second anti-loosening structures fail, the third tooth piece can still prevent the relative rotation between the blade and the motor assembly through rigid engagement. The first anti-loosening structure (first tooth piece-locking hole), the second anti-loosening structure (wedge block-limiting groove) and the third anti-loosening structure (third tooth piece-second tooth-shaped groove) form a three-level anti-rotation protection, covering vibration loads of different directions and frequencies, and improving the system's fault tolerance. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The accompanying drawings constituting a part of the present invention are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the accompanying drawings:

[0022] Figure 1 This is a schematic diagram of a blade loosening prevention device for a drone according to an embodiment of the present invention;

[0023] Figure 2 This is a schematic diagram of the combined structure of the blade structure and the motor assembly according to an embodiment of the present invention;

[0024] Figure 3 This is a schematic diagram of the installation position of the locking mechanism according to an embodiment of the present invention;

[0025] Figure 4 A schematic diagram of the mounting plate structure of the blade structure according to an embodiment of the present invention;

[0026] Figure 5 This is a schematic diagram of the first tooth plate before installation according to an embodiment of the present invention;

[0027] Figure 6 This is a schematic diagram of the first tooth piece after installation according to an embodiment of the present invention;

[0028] Figure 7 This is a schematic diagram of a first anti-loosening structure according to an embodiment of the present invention;

[0029] Figure 8 This is a schematic diagram of the locking mechanism structure according to an embodiment of the present invention;

[0030] Fig. 9 The wedge block structure described in the embodiment of the present invention;

[0031] Fig.10 This is a schematic diagram of a second anti-loosening structure according to an embodiment of the present invention;

[0032] Fig.11 This is a schematic diagram of a third anti-loosening structure according to an embodiment of the present invention;

[0033] Fig.12 It is a schematic diagram of the structure of the elastic tightening mechanism described in an embodiment of the present invention.

[0034] Description of reference numerals:

[0035] 100, UAV body; 200, machine arm; 210, motor assembly; 300, locking mechanism; 310, first gasket; 311, first tooth piece; 312, locking piece; 313, buffer assembly; 314, wedge block; 315, locking hole; 320, second gasket; 321, second tooth piece; 322, limiting groove; 330, third gasket; 331, third tooth piece; 332, rubber sleeve; 333, pressing block; 334, return spring; 335, guide rod; 400, blade structure; 410, mounting plate. DETAILED DESCRIPTION

[0036] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments may be combined with each other.

[0037] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and the like are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, features defined as "first", "second", and the like may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "multiple" means two or more.

[0038] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood by specific circumstances.

[0039] The present invention will be described in detail below with reference to the accompanying drawings and in conjunction with embodiments.

[0040] A blade loosening prevention device for a drone, such as Figure 1 As shown, it includes a UAV body 100, four arms 200, four motor assemblies 210, four blade structures 400 and multiple locking mechanisms 300; the four arms 200 are evenly distributed on the UAV body 100, the motor assembly 210 is arranged at the end of the arm 200 away from the UAV body 100, and the outer rotor shell of one motor assembly 210 is connected to one blade structure 400 through multiple locking mechanisms 300; in this example, the outer rotor shell of one motor assembly 210 is connected to one blade structure 400 through four locking mechanisms 300.

[0041] The locking mechanism 300 includes a first anti-loosening structure, a fixing bolt and a buffer assembly 313. The fixing bolt passes through the first anti-loosening structure and the mounting plate 410 of the blade structure 400 and is connected to the outer rotor housing of the motor assembly 210. The buffer assembly 313 is arranged on the lower end surface of the first anti-loosening structure.

[0042] The first anti-loosening structure includes a first gasket 310, a plurality of first tooth pieces 311 and a plurality of locking pieces 312. The plurality of first tooth pieces 311 are evenly arranged on the outer end surface of the first gasket 310. The plurality of locking pieces 312 are evenly arranged on the upper end surface of the first gasket 310. The mounting plate 410 of the blade structure 400 is provided with one or more locking holes 315 that can cooperate with the first tooth pieces 311. The locking piece 312 can limit and fix the countersunk head of the bolt or the outer surface of the nut. The locking piece 312 and the first tooth piece 311 can be bent. The buffer component 313 is provided on the lower end surface of the first gasket 310. The first gasket 310 is provided with a plurality of square holes for placing the locking pieces 312. The plurality of square holes are evenly arranged on the first gasket 310. The number of the locking pieces 312 and the number of the square holes are both 4. The buffer component 313 is an annular rubber ring. The first teeth 311 evenly distributed on the outer circumference of the first gasket 310 cooperate with the lock hole 315 on the blade mounting plate 410 to form a direct mechanical interlocking structure. When the blade is vibrated, the engagement of the first teeth 311 with the lock hole 315 can effectively inhibit the relative rotation between the blade and the motor assembly 210, and prevent the bolt from loosening due to the circumferential shear force. The bendable lock piece 312 above the first gasket 310 wraps the countersunk head or the outer surface of the nut of the fixing bolt, and uses the elastic deformation of the lock piece 312 to generate a continuous clamping force. This elastic limit can not only offset the attenuation of the bolt preload caused by vibration, but also directly limit the rotational freedom of the bolt through physical blocking. The annular rubber ring at the lower end of the first gasket 310 serves as a buffer component 313, which can absorb the energy generated by the high-frequency vibration of the motor during the flight of the drone and reduce the vibration amplitude transmitted to the fixing bolt. By reducing the dynamic load of the bolt, the loosening caused by fatigue is delayed. The locking piece 312 and the first tooth piece 311 are both designed as bendable structures, allowing local elastic deformation when subjected to vibration or impact, avoiding stress concentration or structural fracture due to excessive rigidity, and improving the adaptability of the device to complex working conditions.

[0043] The locking mechanism 300 also includes a second anti-loosening structure. A plurality of wedge blocks 314 are evenly arranged on the circumference of the lower end surface of the first gasket 310. The second anti-loosening structure includes a second gasket 320 and a plurality of second tooth pieces 321. The plurality of second tooth pieces 321 are evenly arranged on the circumference of the outer end surface of the second gasket 320. The upper end surface of the second gasket 320 is provided with a plurality of limiting grooves 322 that can cooperate with the wedge blocks 314. The mounting plate 410 of the blade structure 400 is provided with a first notch that can accommodate the second gasket 320. The inner wall of the first notch cooperates with the second tooth piece 321 through the first tooth-shaped groove. The plurality of wedge blocks 314 at the lower end of the first gasket 310 and the limiting groove 322 at the upper end of the second gasket 320 form an inclined locking structure. The second tooth piece 321 on the outer side of the second gasket 320 meshes with the first tooth-shaped groove on the inner wall of the first notch of the mounting plate 410 to form a second anti-rotation barrier. Even if the first tooth piece 311 of the first anti-loosening structure fails to cooperate with the lock hole 315, the second tooth piece 321 can still prevent the relative movement between the blade and the outer rotor housing of the motor assembly 210 through rigid engagement. The second anti-loosening structure transfers the load of the first anti-loosening structure to the first notch of the mounting plate 410 through the second gasket 320, thereby expanding the contact area of ​​the force and avoiding stress concentration on a single component (such as the first gasket 310 or the bolt). This layered design significantly improves the fatigue resistance of the overall structure.

[0044] The locking mechanism 300 also includes a third anti-loosening structure, which includes a third gasket 330, a rubber sleeve 332, a plurality of elastic tightening mechanisms and a plurality of third tooth pieces 331. A second notch capable of placing the third gasket 330 is provided at the bottom of the first notch, and the inner wall of the second notch cooperates with the third tooth piece 331 through a second tooth-shaped groove. A plurality of third tooth pieces 331 are evenly arranged on the outer end surface of the third gasket 330. The third gasket 330 is provided with a circular hole capable of placing the rubber sleeve 332. A plurality of elastic tightening mechanisms are evenly arranged on the inner side of the circular hole. One end of the elastic tightening mechanism is connected to the inner wall of the circular hole, and the other end of the elastic tightening mechanism is arranged in the hole where the fixing bolt is installed. When the fixing bolt is installed, the elastic tightening mechanism squeezes the bottom of the rubber sleeve 332, so that the top of the rubber sleeve 332 presses the lower end surface of the second gasket 320. When the fixing bolt is installed, the rubber sleeve 332 is squeezed by the elastic tightening mechanism to generate axial preload compensation. When the bolt is slightly loosened due to vibration or temperature change, the elastic restoring force of the rubber sleeve 332 can automatically fill the gap and continuously compress the second gasket 320 and the third gasket 330 to prevent the preload force from decaying. The third tooth piece 331 on the outside of the third gasket 330 engages with the second tooth-shaped groove on the inner wall of the second notch to form a third anti-rotation barrier. Even if the first and second anti-loosening structures fail, the third tooth piece 331 can still prevent the relative rotation between the blade and the motor assembly 210 through rigid engagement. The first anti-loosening structure (first tooth piece-locking hole 315), the second anti-loosening structure (wedge block 314-limiting groove 322) and the third anti-loosening structure (third tooth piece 331-second tooth-shaped groove) form a three-level anti-rotation protection, covering vibration loads of different directions and frequencies, and improving the system's fault tolerance.

[0045] The elastic tightening mechanism includes a guide rod 335, a return spring 334 and a tightening block 333. One end of the guide rod 335 is connected to the inner wall of the circular hole, and the outer end of the guide rod 335 is slidably matched with the tightening block 333. The return spring 334 is arranged on the guide rod 335. One end of the return spring 334 abuts against the tightening block 333, and the other end of the return spring 334 abuts against the bottom of the rubber sleeve 332. The end of the tightening block 333 is provided with an inclined surface, which is arranged in the channel where the fixing bolt is installed.

[0046] How this example works

[0047] The first gasket 310 is clamped on the bolt / nut, and the upward locking plate 312 is clamped into the hexagonal surface of the bolt or nut, so that the first gasket 310 forms a rotational lock with the screw, and the gasket will rotate with the rotation of the screw. Similarly, when the first tooth plate 311 is embedded in the locking hole 315, the first gasket 310 fixes the blade structure 400, and the fixing bolt is fixed together with the first gasket 310 to prevent the screw from loosening. The blade structure 400 is placed on the outer rotor housing of the drone motor, and the four fixing bolt holes are aligned with the mounting holes on the motor. The holes of the blade structure 400 with multiple locking holes 315 around the screw holes face upward. The bolts and nuts are screwed into the threaded holes through the workpiece to be installed, and screwed to the maximum tightening state.

[0048] The first tooth piece 311 of the first gasket 310 is aligned with the locking hole 315 of the fixed blade and bent downward to fit into the hole, so that the first gasket 310 is fixed to the blade, thereby realizing the anti-loosening structure of fixing the blade and the gasket, and then fixing the gasket to the bolt and nut. Figure 6 shows the buckle locking state.

[0049] The relationship between the number of teeth of the first tooth piece 311 and the number of buckle holes of the installed workpiece will affect the fixing resolution of the screw. For example, if the number of teeth of the gasket is 36 and the angle of each first tooth piece is 10 degrees, if the number of holes of the locking hole 315 is divisible by 36, then multiple first tooth pieces 311 can be locked at the same time, and the resolution of the bolt or nut tightening is 10 degrees. If the number of holes of the locking hole 315 is not divisible by 36, for example, the number of holes is 5, then only one first tooth piece 311 is in the locked state in the tightening state, and the tightening resolution is 10 degrees / 5 equals 2 degrees. In principle, the angle rate calculation method for screw tightening is:

[0050] (1) The number of snap holes on the mounting plate 410 cannot be divided evenly by the number of teeth on the gasket, 360 degrees / number of teeth on the gasket / number of snap holes on the fixed part.

[0051] (2) The number of snap holes on the mounting plate 410 can be divided evenly by the number of teeth on the gasket, 360 degrees / number of teeth on the gasket.

[0052] The angle variation rate of the fixing bolt tightening also refers to the acceptable loose angle of the product. For example, if the fixing angle resolution is 2 degrees, then when we tighten the screw to any position, there must be a locking hole 315 within ±1 degree of this position that can be aligned with the first tooth piece 311.

[0053] To remove the fixing bolts, use a socket tool to press down the first gasket 310. The lower surface of the socket will flatten the upturned locking plate 312 of the first gasket 310. The bolts and nuts can be removed normally. The first gasket 310 has a certain metal elasticity and can be restored to its original state. The originally bent first tooth plate 311 can be restored using tools such as pliers and used again.

[0054] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A blade loosening prevention device for a drone, characterized in that: It comprises a drone body (100), four arms (200), four motor assemblies (210), four blade structures (400) and a plurality of locking mechanisms (300); The four machine arms (200) are evenly distributed on the drone body (100); the motor assembly (210) is arranged at an end of the machine arm (200) away from the drone body (100); and the outer rotor housing of one motor assembly (210) is connected to one blade structure (400) via a plurality of locking mechanisms (300); The locking mechanism (300) comprises a first anti-loosening structure, a fixing bolt and a buffer assembly (313); the fixing bolt penetrates through the first anti-loosening structure and a mounting plate (410) of the blade structure (400) and is connected to an outer rotor housing of the motor assembly (210); and the buffer assembly (313) is arranged on a lower end surface of the first anti-loosening structure; The first anti-loosening structure comprises a first gasket (310), a plurality of first tooth pieces (311) and a plurality of locking pieces (312); the plurality of first tooth pieces (311) are evenly arranged circumferentially on the outer end surface of the first gasket (310); the plurality of locking pieces (312) are evenly arranged circumferentially on the upper end surface of the first gasket (310); the mounting plate (410) of the blade structure (400) is provided with one or more locking holes (315) capable of cooperating with the first tooth pieces (311); the locking piece (312) can limit and fix the countersunk head of the bolt or the outer surface of the nut; the locking piece (312) and the first tooth piece (311) can be bent; and the buffer component (313) is arranged on the lower end surface of the first gasket (310).

2. The blade loosening prevention device for a drone according to claim 1, characterized in that: The locking mechanism (300) further comprises a second anti-loosening structure, wherein a plurality of wedge blocks (314) are evenly arranged on the circumference of the lower end surface of the first gasket (310), and the second anti-loosening structure comprises a second gasket (320) and a plurality of second tooth plates (321), wherein the plurality of second tooth plates (321) are evenly arranged on the circumference of the outer end surface of the second gasket (320), and the upper end surface of the second gasket (320) is provided with a plurality of limiting grooves (322) capable of cooperating with the wedge blocks (314), and a first notch capable of accommodating the second gasket (320) is provided on the mounting plate (410) of the blade structure (400), and the inner wall of the first notch is matched with the second tooth plate (321) through a first tooth-shaped groove.

3. The blade loosening prevention device for a drone according to claim 2, characterized in that: The locking mechanism (300) also includes a third anti-loosening structure, which includes a third gasket (330), a rubber sleeve (332), a plurality of elastic tightening mechanisms and a plurality of third tooth pieces (331). A second notch capable of accommodating the third gasket (330) is provided at the bottom of the first notch. The inner wall of the second notch cooperates with the third tooth piece (331) through a second tooth-shaped groove. The plurality of third tooth pieces (331) are uniformly arranged on the outer end surface of the third gasket (330). The third gasket (330) is provided with a circular hole capable of accommodating the rubber sleeve (332). The plurality of elastic tightening mechanisms are uniformly arranged on the inner side of the circular hole. One end of the elastic tightening mechanism is connected to the inner wall of the circular hole. The other end of the elastic tightening mechanism is arranged in a channel where a fixing bolt is installed. When the fixing bolt is installed, the elastic tightening mechanism squeezes the bottom of the rubber sleeve (332) so that the top of the rubber sleeve (332) presses the lower end surface of the second gasket (320).

4. The blade loosening prevention device for a drone according to claim 3, characterized in that: The elastic pressing mechanism comprises a guide rod (335), a return spring (334) and a pressing block (333); one end of the guide rod (335) is connected to the inner wall of the circular hole; the outer end of the guide rod (335) is slidably matched with the pressing block (333); the return spring (334) is arranged on the guide rod (335); one end of the return spring (334) abuts against the pressing block (333); the other end of the return spring (334) abuts against the bottom of the rubber sleeve (332); an inclined surface is provided at the end of the pressing block (333); and the inclined surface is arranged in a hole where a fixing bolt is installed.

5. A blade anti-loosening device for a drone according to any one of claims 1 to 4, characterized in that: The first gasket (310) is provided with a plurality of square holes for accommodating the locking plates (312), and the plurality of square holes are evenly arranged on the circumference of the first gasket (310).

6. The blade loosening prevention device for a drone according to claim 5, characterized in that: The number of the locking pieces (312) and the number of the square holes are both four.

7. The blade loosening prevention device for a drone according to claim 4, characterized in that: The buffer component (313) is an annular rubber ring.

8. The blade loosening prevention device for a drone according to claim 5, characterized in that: An outer rotor housing of a motor assembly (210) is connected to a blade structure (400) via four locking mechanisms (300).

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