Multi-rotor unmanned aerial vehicle arm automatic unfolding and folding structure and unmanned aerial vehicle

Abstract

The invention provides a multi-rotor unmanned aerial vehicle arm automatic unfolding and folding structure and an unmanned aerial vehicle, the multi-rotor unmanned aerial vehicle arm automatic unfolding and folding structure is used for automatically unfolding and folding an arm of a multi-rotor unmanned aerial vehicle, and the multi-rotor unmanned aerial vehicle arm automatic unfolding and folding structure comprises an arm rotating shaft assembly, a rotating shaft seat assembly, a locking motor assembly, a rotating arm steering engine and a driving shaft; the locking motor assembly is arranged on the rotating shaft seat assembly, the rotating shaft seat assembly is connected with the arm rotating shaft assembly through the driving shaft, and the rotating arm steering engine is matched with the driving shaft to drive the arm rotating shaft assembly to rotate; when the vehicle arms are unfolded, the rotating shaft seat assembly sends a signal after acquiring that the vehicle arm rotating shaft assembly reaches the designated unfolding position, the locking motor assembly locks the vehicle arm rotating shafts, the vehicle arm rotating shafts are prevented from rotating in the flying process, and the problems that a multi-rotor unmanned aerial vehicle is large in storage space requirement and difficult to achieve automatic unfolding and folding can be solved.

Description

[Technical field]

[0001] The present invention relates to the technical field of unmanned aerial vehicles, and in particular to an automatic extension and retraction structure of a multi-rotor unmanned aerial vehicle arm and the unmanned aerial vehicle. [Background technology]

[0002] In recent years, with the development of drone technology, the application of drones has expanded to various fields such as urban management, logistics and transportation, personnel search and rescue, security detection, agricultural environment, etc. For multi-rotor drones, they can achieve vertical take-off and landing and free hovering, and they are low-priced and easy to operate, making the market for multi-rotor drones more extensive.

[0003] In order to reduce storage and transportation space, the arms of existing large multi-rotor drones are usually designed to be detachable or foldable. However, the current arm folding structure is mostly manually unfolded and folded, which makes the storage and transportation of multi-rotors convenient, but cannot meet the requirements of efficient autonomous take-off and landing of future multi-rotor drones, and to some extent limits the development of multi-rotor drones towards intelligence and miniaturization.

[0004] Therefore, it is necessary to study a multi-rotor UAV arm automatic extension and retraction structure and a UAV to address the deficiencies of the prior art and to solve or alleviate one or more of the above problems. [Summary of the invention]

[0005] In view of this, the present invention provides a multi-rotor UAV arm automatic extension and retraction structure and a UAV, aiming to solve the problem that multi-rotor UAVs have large storage space requirements and are difficult to achieve automatic extension and retraction.

[0006] On the one hand, the present invention provides a multi-rotor UAV arm automatic extension and retraction structure, which is used to automatically extend and retract the arms of the multi-rotor UAV, and the multi-rotor UAV arm automatic extension and retraction structure comprises: an arm shaft assembly, a shaft seat assembly, a locking motor assembly, an arm servo and a drive shaft;

[0007] The locking motor assembly is arranged on the rotating shaft seat assembly, the rotating shaft seat assembly is connected to the machine arm rotating shaft assembly through the driving shaft, and the rotating arm servo cooperates with the driving shaft to drive the machine arm rotating shaft assembly to rotate;

[0008] When the arm is unfolded, the shaft seat assembly senses that the arm shaft assembly has reached the designated unfolding position, and sends a signal to lock the motor assembly to lock the arm shaft to prevent the arm shaft from rotating during flight.

[0009] According to the above aspects and any possible implementation, there is further provided an implementation, wherein the shaft seat assembly includes a shaft seat, a micro bearing, a photoelectric switch and an arm stowage fixing seat;

[0010] The locking motor assembly is fixed on the rotating shaft seat;

[0011] The micro bearing is used to reduce the friction force when the arm shaft assembly rotates;

[0012] The photoelectric switch cooperates with the arm shaft assembly to send an in-position signal;

[0013] The machine arm stowage fixing seat is used to fix the machine arm that is about to be stowed.

[0014] According to the aspects described above and any possible implementation method, an implementation method is further provided, wherein the arm shaft assembly includes an arm shaft and a baffle, wherein the baffle is fixed to the arm shaft and cooperates with a photoelectric switch to control the action of the locking motor assembly.

[0015] According to the aspects described above and any possible implementation, an implementation is further provided, wherein the locking motor assembly includes a locking motor adapter plate, a locking motor mounting seat and a locking motor, and the locking motor mounting seat is used to connect and fix the locking motor to the locking motor adapter plate.

[0016] As described above and any possible implementation method, an implementation method is further provided. When unfolded horizontally, the locking motor connecting plate is used to strengthen the shaft seat; when unfolded longitudinally, the locking motor connecting plate is used to support the end of the arm shaft to balance the torque generated by the lift.

[0017] According to the aspects described above and any possible implementation method, an implementation method is further provided, wherein a conical locking hole and a manual locking hole are provided on the arm shaft, the conical locking hole is used to guide and fix the push rod of the locking motor, and the manual locking hole is used to manually fix the locking motor when it fails. A cable hole is also provided at the end of the arm shaft for passing the power cable of the electronic speed regulator.

[0018] According to the aspects described above and any possible implementation method, an implementation method is further provided, wherein the drive shaft is provided with an inner sleeve tooth, and the inner sleeve tooth is used to cooperate with the output shaft of the boom servo to transmit the torque of the boom servo to the drive shaft, and the torque is transmitted to the arm shaft by cooperating with the hexagonal shaft section of the inner sleeve tooth and the hexagonal shaft hole of the arm shaft.

[0019] According to the aspects described above and any possible implementation method, an implementation method is further provided, wherein the shaft seat includes a shaft seat connecting plate and a shaft seat mounting plate, bearing mounting holes are arranged on the shaft seat connecting plates on both sides, and a servo positioning seat and a locking threaded hole are arranged on the shaft seat connecting plate, wherein the servo positioning seat is used for positioning and installing the swivel arm servo; the locking threaded hole is connected to the manual locking hole for manual fixation when the motor fails.

[0020] According to the aspects described above and any possible implementation method, an implementation method is further provided, wherein a rotating shaft seat mounting tenon is provided on the mounting surface of the rotating shaft seat mounting plate, which is used to cooperate with the fuselage mounting tenon groove of the multi-rotor drone to improve the carrying capacity of the arm.

[0021] According to the above aspects and any possible implementation, a drone is further provided, on which the multi-rotor drone arm automatic extension and retraction structure is provided.

[0022] Compared with the prior art, the present invention can achieve the following technical effects:

[0023] 1) The present invention provides an automatic extension and retraction structure for the arms of a multi-rotor UAV, which belongs to the technical field of UAVs and solves the problems of large storage space requirements, inconvenient retraction and deployment, and difficulty in automating take-off and landing of multi-rotor UAVs;

[0024] 2) After the locking motor assembly and the shaft seat assembly are installed, the arm shaft assembly and the shaft seat assembly are connected through the drive shaft, and the arm steering gear output shaft cooperates with the inner sleeve gear of the drive shaft to drive the arm shaft assembly to rotate. When the arm is unfolded, the photoelectric switch senses that the baffle has reached the designated unfolding position, sends a signal, and the locking motor push rod extends to lock the arm shaft to prevent the arm shaft from rotating during flight.

[0025] 3) The present invention utilizes the driving torque and angle positioning function of the rotary arm servo to realize the automatic deployment and folding of the arm, thereby reducing the storage space to the greatest extent. At the same time, after deployment, the arm is locked by a locking motor, thereby ensuring the safety of the flight process and facilitating the automatic control of the take-off and recovery of the UAV.

[0026] Of course, any product implementing the present invention does not necessarily need to achieve all of the above-mentioned technical effects at the same time.

Brief Description of the Drawings

[0027] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0028] Figure 1 This is a schematic diagram of the lateral unfolding and folding of the automatic unfolding and folding structure of the arms of a multi-rotor UAV proposed by the present invention;

[0029] Figure 2 A schematic diagram of the automatic extension and retraction structure of the arms of a multi-rotor UAV proposed by the present invention;

[0030] Figure 3This is a cross-sectional schematic diagram of the driving axis position of a multi-rotor UAV arm automatic extension and retraction structure proposed by the present invention;

[0031] Figure 4 This is a schematic diagram of the structure of the arm shaft assembly of the present invention;

[0032] Figure 5 This is a schematic diagram of the structure of the rotating shaft seat assembly of the present invention;

[0033] Figure 6 This is a schematic diagram of the structure of the locking motor assembly of the present invention;

[0034] Figure 7 This is a schematic diagram of the arm shaft structure of the present invention;

[0035] Figure 8 This is a schematic diagram of the structure of the rotating shaft seat of the present invention;

[0036] Fig. 9 This is a schematic diagram of the drive shaft structure of the present invention;

[0037] Fig.10 This is a schematic diagram of the longitudinal deployment and folding of the automatic deployment and folding structure of the arms of a multi-rotor UAV proposed by the present invention.

[0038] In the figure: 1. Arm shaft assembly; 2. Shaft seat assembly; 3. Locking motor assembly; 4. Arm servo; 5. Drive shaft; 6. Arm tube; 7. Motor seat; 8. Power motor; 11. Arm shaft; 12. Baffle; 21. Shaft seat; 22. Miniature bearing; 23. Photoelectric switch; 24. Arm stowage fixing seat; 31. Locking motor adapter plate; 32. Locking motor mounting seat; 33. Locking motor; 51. Inner sleeve gear; 52. Hexagonal shaft section; 111. Conical locking hole; 112. Hexagonal shaft hole; 113. Cable hole; 114. Manual locking hole; 211. Shaft seat connecting plate; 212. Shaft seat mounting plate; 213. Servo positioning seat; 214. Bearing mounting hole; 215. Locking threaded hole; 216. Shaft seat mounting tenon. [Specific implementation method]

[0039] In order to better understand the technical solution of the present invention, the embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0040] It should be clear that the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0041] The terms used in the embodiments of the present invention are only for the purpose of describing specific embodiments, and are not intended to limit the present invention. The singular forms "a", "said" and "the" used in the embodiments of the present invention and the appended claims are also intended to include plural forms, unless the context clearly indicates other meanings.

[0042] The present invention provides an automatic arm extension and retraction structure for a multi-rotor UAV, which is used to automatically extend and retract the arm of the multi-rotor UAV. The automatic arm extension and retraction structure for the multi-rotor UAV comprises: an arm shaft assembly, a shaft seat assembly, a locking motor assembly, an arm steering gear and a drive shaft;

[0043] The locking motor assembly is arranged on the rotating shaft seat assembly, the rotating shaft seat assembly is connected to the machine arm rotating shaft assembly through the driving shaft, and the rotating arm servo cooperates with the driving shaft to drive the machine arm rotating shaft assembly to rotate;

[0044] When the arm is unfolded, the shaft seat assembly senses that the arm shaft assembly has reached the designated unfolding position, and sends a signal to lock the motor assembly to lock the arm shaft to prevent the arm shaft from rotating during flight.

[0045] In a specific embodiment, the arm shaft assembly includes an arm shaft and a baffle.

[0046] In a specific embodiment, the blocking piece is fixed on the rotating shaft of the machine arm and cooperates with the photoelectric switch to control the action of the locking motor.

[0047] In a specific embodiment, a conical locking hole is provided on the arm shaft for guiding and fixing the locking motor push rod. The manual locking hole is used for manual fixing when the locking motor fails. A cable hole is left at the end of the arm shaft for the power cable of the electronic speed controller to pass through.

[0048] In a specific embodiment, the shaft seat assembly includes a shaft seat, a micro bearing, a photoelectric switch, and an arm folding fixing seat.

[0049] In a specific embodiment, the shaft seat is composed of a shaft seat connecting plate and a shaft seat mounting plate. The shaft seat connecting plates on both sides are provided with bearing mounting holes, and the shaft seat connecting plates on each side are respectively provided with a steering gear positioning seat and a locking threaded hole.

[0050] In a specific embodiment, the steering gear positioning seat is used for positioning and installing the swivel arm steering gear. The locking threaded hole is connected to the manual locking hole through a locking pin, which is used for manual fixation when the locking motor fails.

[0051] In a specific embodiment, a rotating shaft seat mounting tenon is provided on the mounting surface of the rotating shaft seat mounting plate, which is used to cooperate with the mounting tenon groove of the fuselage to improve the bearing capacity of the machine arm.

[0052] In a specific embodiment, the micro bearing is used to reduce the friction force when the arm shaft assembly rotates, and the photoelectric switch cooperates with the baffle to send a positioning signal. The arm stowage fixing seat is used to fix the arm that is about to be stowed.

[0053] In a specific embodiment, the locking motor assembly includes a locking motor adapter plate, a locking motor mounting seat and a locking motor.

[0054] In a specific embodiment, the locking motor assembly is connected and fixed to the locking motor and the locking motor adapter plate through the locking motor mounting seat. When the locking motor is deployed horizontally, the locking motor connecting plate plays the role of strengthening the rotating shaft seat. When the locking motor is deployed vertically, it plays the role of supporting the rotating shaft of the machine arm and offsetting the torque generated by the lift.

[0055] In a specific embodiment, the locking motor assembly is installed on the shaft seat assembly, the arm shaft assembly and the shaft seat assembly are connected through the drive shaft, and the arm servo output shaft cooperates with the inner sleeve gear of the drive shaft to drive the arm shaft assembly to rotate.

[0056] In a specific embodiment, when the arm is deployed, the photoelectric switch senses that the baffle has reached the designated deployment position and sends a signal to extend the locking motor push rod to lock the arm shaft to prevent the arm shaft from rotating during flight.

[0057] In a specific embodiment, the drive shaft is made of alloy steel, and the inner sleeve gear thereon cooperates with the output shaft of the arm servo to transmit the torque of the arm servo to the drive shaft, and the hexagonal shaft section cooperates with the hexagonal shaft hole of the arm shaft to transmit the torque to the arm shaft.

[0058] The present invention also provides a UAV, on which is provided a multi-rotor UAV arm automatic extension and retraction structure.

[0059] Example 1: Multi-rotor UAV arm automatic lateral extension and retraction structure

[0060] like Figure 1 As shown, the automatic extension and retraction structure of the drone arm of the present invention, together with the arm tube 6, the motor seat 7 and the power motor 8, constitute the drone arm that can be automatically extended and retracted. When horizontally extended and retracted, the axis of the drive motor 8 is perpendicular to the rotation plane of the arm. Figure 1 The solid line in the middle represents the arm's extended state, and the dotted line represents the arm's retracted state. Taking a quadrotor as an example, the arm's extension and retraction angle of a quadrotor drone is 135°.

[0061] like Figure 2 As shown, the automatic extension and retraction structure of the drone arm of the present invention is composed of an arm shaft assembly 1, a shaft seat assembly 2, a locking motor assembly 3, an arm servo 4, and a drive shaft 5. The torque output by the arm servo 4 is transmitted to the arm shaft assembly 1 through the drive shaft 5, thereby driving the entire arm to rotate.

[0062] like Figure 3 As shown, a vertical section of the drive shaft 5 is shown. The arm servo 4 is connected and fixed to the shaft seat 21 by screws, and the outer sleeve teeth of the output shaft of the arm servo 4 cooperate with the inner sleeve teeth 51 of the drive shaft 5 to transmit torque. The drive shaft 5, the miniature bearing 22, and the arm shaft 11 are connected by a self-locking nut to prevent the drive shaft 5 from coming out along its axial direction.

[0063] like Figure 4 As shown, the arm shaft assembly 1 consists of an arm shaft 11 and a baffle 12. The baffle 12 is fixed on the arm shaft 11 and cooperates with the photoelectric switch 23. When it is deployed, the photoelectric switch 23 sends a control signal to control the locking motor 33 to extend the push rod.

[0064] like Figure 7 As shown, the conical locking hole 111 on the arm shaft 11 is used to guide and fix the push rod of the locking motor 33, and the manual locking hole 114 is used for manual locking when the locking motor 33 fails. A cable hole 113 is left at the end of the arm shaft 11 for the power cable of the electronic speed controller to pass through.

[0065] like Figure 5 As shown, the shaft seat assembly includes a shaft seat 21, a micro bearing 22, a photoelectric switch 23, and an arm stowage fixing seat 24. The micro bearing 22 is used to reduce the friction force when the arm shaft assembly 1 rotates. The arm stowage fixing seat 24 is used to fix the arm that is about to be stowed, so as to reduce the impact of the vibration load on the arm structure during transportation.

[0066] like Figure 8 As shown, the shaft seat 21 is composed of a shaft seat connecting plate 211 and a shaft seat mounting plate 212. In this example, the shaft seat is processed as an integral body, and can also be processed into a split structure according to the actual load conditions. The shaft seat connecting plates 211 on both sides are respectively provided with bearing mounting holes 214, and the bearing seat mounting holes 214 should strictly ensure coaxiality. A servo positioning seat 213 is provided on the shaft seat connecting plate 211 on one side. The servo positioning seat 211 is used for positioning and installing the swivel arm servo 4. A locking threaded hole 215 is provided on the shaft seat connecting plate 211 on the other side. The locking threaded hole 215 is connected to the manual locking hole 114 through a locking pin, and is used for manual fixation when the locking motor 33 fails.

[0067] The mounting surface of the shaft mounting plate 212 is provided with a shaft mounting tenon 216, which cooperates with the fuselage mounting tenon groove to improve the bearing capacity of the machine arm.

[0068] like Figure 6 As shown, the locking motor 33 is connected and fixed to the locking motor adapter plate 31 through the locking motor mounting seat 32. When the locking motor is horizontally unfolded, the locking motor connecting plate 31 plays a role in strengthening the rotating shaft seat 21.

[0069] like Fig. 9 As shown, an inner sleeve gear 51 is provided at the shaft end of the driving shaft 5, which cooperates with the output shaft of the boom servo 4 to transmit the torque of the boom servo 4 to the driving shaft 5, and cooperates with the hexagonal shaft hole 112 of the arm shaft 11 through the hexagonal shaft section 52 to further transmit the torque to the arm shaft 11.

[0070] Example 2: Multi-rotor UAV arm longitudinal automatic extension and retraction structure

[0071] The automatic longitudinal extension and retraction structure of the multi-rotor UAV arm of this embodiment 2 is a modified product embodiment of the automatic transverse extension and retraction structure of the multi-rotor UAV arm of embodiment 1.

[0072] like Fig.10 As shown, the motor base 7 is rotated 90°, and the axis of the power motor 8 is parallel to the rotating surface of the machine arm. Fig.10 In the figure, the solid line is the state of the arm being deployed, the dotted line is the state of the arm being retracted, and the arm deployment angle of the unmanned aerial vehicle is 90°. When deployed longitudinally, the locking motor connecting plate 31 supports the end of the arm rotating shaft 11 to balance the torque generated by the lift.

[0073] The present invention solves the problems of large storage space requirements, inconvenient folding and unfolding, and difficulty in automating take-off and landing of multi-rotor drones. After the locking motor assembly and the shaft seat assembly are installed, the arm shaft assembly and the shaft seat assembly are connected through a drive shaft, and the arm steering gear output shaft cooperates with the inner sleeve gear of the drive shaft to drive the arm shaft assembly to rotate. When the arm is unfolded, the photoelectric switch senses that the baffle has reached the designated unfolding position, sends a signal, and the locking motor push rod extends to lock the arm shaft to prevent the arm shaft from rotating during flight.

[0074] The present invention utilizes the driving torque and angle positioning functions of the swivel arm servo to realize automatic deployment and folding of the arm, thereby reducing the storage space to the greatest extent. At the same time, the arm is locked by a locking motor after deployment, thereby ensuring the safety of the flight process and facilitating the automatic control of the take-off and recovery of the UAV.

[0075] The above is a detailed introduction to a multi-rotor drone arm automatic extension and retraction structure and drone provided by the embodiment of the present application. The description of the above embodiment is only used to help understand the method and core idea of ​​the present application; at the same time, for those skilled in the art, according to the idea of ​​the present application, there will be changes in the specific implementation method and application scope. In summary, the content of this specification should not be understood as a limitation on the present application.

[0076] For example, certain words are used in the specification and claims to refer to specific components. Those skilled in the art should understand that hardware manufacturers may use different nouns to refer to the same component. This specification and claims do not use differences in names as a way to distinguish components, but use differences in the functions of components as the criteria for distinction. As mentioned throughout the specification and claims, "including" and "comprising" are open-ended terms, so they should be interpreted as "including / including but not limited to". "Approximately" means that within an acceptable error range, those skilled in the art can solve the technical problem within a certain error range and basically achieve the technical effect. The subsequent description of the specification is a preferred embodiment of the present application, but the description is for the purpose of illustrating the general principles of the present application, and is not used to limit the scope of the present application. The scope of protection of the present application shall be determined by the definition of the attached claims.

[0077] It should also be noted that the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a product or system including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such a product or system. In the absence of more restrictions, the elements defined by the sentence "comprises a ..." do not exclude the existence of other identical elements in the product or system including the elements.

[0078] It should be understood that the term "and / or" used in this article is only a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0079] The above description shows and describes several preferred embodiments of the present application, but as mentioned above, it should be understood that the present application is not limited to the form disclosed herein, and should not be regarded as excluding other embodiments, but can be used in various other combinations, modifications and environments, and can be modified within the scope of the application concept described herein through the above teachings or the technology or knowledge of the relevant field. The changes and modifications made by those skilled in the art do not deviate from the spirit and scope of the present application, and should be within the scope of protection of the claims attached to the present application.

Claims

1. A multi-rotor drone arm automatic deployment and retraction structure, used for automatically deploying and retracting the arms of the multi-rotor drone, characterized in that: The multi-rotor drone arm automatic extension and retraction structure comprises: an arm shaft assembly, a shaft seat assembly, a locking motor assembly, an arm servo and a drive shaft; The locking motor assembly is arranged on the rotating shaft seat assembly, the rotating shaft seat assembly is connected to the machine arm rotating shaft assembly through the driving shaft, and the rotating arm servo cooperates with the driving shaft to drive the machine arm rotating shaft assembly to rotate; When the arm is unfolded, the shaft seat assembly senses that the arm shaft assembly has reached the designated unfolding position, and sends a signal to lock the motor assembly to lock the arm shaft to prevent the arm shaft from rotating during flight.

2. The multi-rotor drone arm automatic extension and retraction structure according to claim 1 is characterized in that: The rotating shaft seat assembly includes a rotating shaft seat, a micro bearing, a photoelectric switch and an arm stowage fixing seat; The locking motor assembly is fixed on the rotating shaft seat; The micro bearing is used to reduce the friction force when the arm shaft assembly rotates; The photoelectric switch cooperates with the arm shaft assembly to send an in-position signal; The machine arm stowage fixing seat is used to fix the machine arm that is about to be stowed.

3. The multi-rotor drone arm automatic extension and retraction structure according to claim 2 is characterized in that: The arm shaft assembly comprises an arm shaft and a baffle, wherein the baffle is fixed on the arm shaft and cooperates with a photoelectric switch to control the action of the locking motor assembly.

4. The multi-rotor drone arm automatic extension and retraction structure according to claim 3 is characterized in that: The locking motor assembly comprises a locking motor adapter plate, a locking motor mounting seat and a locking motor, wherein the locking motor mounting seat is used to connect and fix the locking motor to the locking motor adapter plate.

5. The multi-rotor drone arm automatic extension and retraction structure according to claim 4 is characterized in that: When deployed horizontally, the locking motor connecting plate is used to strengthen the shaft seat; when deployed longitudinally, the locking motor connecting plate is used to support the end of the arm shaft to balance the torque generated by the lift.

6. The multi-rotor drone arm automatic extension and retraction structure according to claim 5, characterized in that: A conical locking hole and a manual locking hole are provided on the arm shaft. The conical locking hole is used to guide and fix the push rod of the locking motor, and the manual locking hole is used to manually fix the locking motor when it fails. A cable hole is also provided at the end of the arm shaft for the power cable of the electronic speed regulator to pass through.

7. The multi-rotor drone arm automatic extension and retraction structure according to claim 1, characterized in that: The drive shaft is provided with an inner sleeve gear, and the inner sleeve gear is used to cooperate with the output shaft of the arm servo to transmit the torque of the arm servo to the drive shaft. The hexagonal shaft section of the inner sleeve gear cooperates with the hexagonal shaft hole of the arm shaft to transmit the torque to the arm shaft.

8. The multi-rotor drone arm automatic extension and retraction structure according to claim 6, characterized in that: The rotating shaft seat includes a rotating shaft seat connecting plate and a rotating shaft seat mounting plate. The rotating shaft seat connecting plates on both sides are provided with bearing mounting holes. The rotating shaft seat connecting plates are provided with a servo positioning seat and a locking threaded hole. The servo positioning seat is used for positioning and installing the swivel arm servo; the locking threaded hole is connected to the manual locking hole, and is used for manual fixation when the locking motor fails.

9. The multi-rotor drone arm automatic extension and retraction structure according to claim 8, characterized in that: A rotating shaft seat mounting tenon is provided on the mounting surface of the rotating shaft seat mounting plate, which is used to cooperate with the fuselage mounting tenon groove of the multi-rotor UAV to improve the bearing capacity of the aircraft arm.

10. A drone, characterized in that: The drone is provided with the multi-rotor drone arm automatic extension and retraction structure as described in any one of claims 1-9.

Images