WO2021098452A1

WO2021098452A1 - Folding paddle mechanism and unmanned aerial vehicle

Info

Publication number: WO2021098452A1
Application number: PCT/CN2020/124043
Authority: WO
Inventors: 钟自鸣
Original assignee: 深圳市道通智能航空技术股份有限公司
Priority date: 2019-11-21
Filing date: 2020-10-27
Publication date: 2021-05-27
Also published as: CN111003163B; CN111003163A

Abstract

Disclosed are a folding paddle mechanism (10) and an unmanned aerial vehicle (100). The folding paddle mechanism (10) comprises a paddle clamp base (21), a paddle clamp upper cover (22), paddles (1), connecting shafts (33) and a damping device which is used for forming resistance to the rotation of the paddles (1). The paddle clamp upper cover (22) and the paddle clamp base (21) are arranged in a spaced manner; the paddles (1) each comprise a fixed end (11) and a free end (12); the fixed end (11) is clamped between the paddle clamp base (21) and the paddle clamp upper cover (22); the connecting shafts (33) are arranged in the paddle clamp base (21), the paddles (1) and the paddle clamp upper cover (22) in a penetrating manner; the connecting shafts (33) are fixedly connected to the fixed ends (11); the connecting shafts (33) are rotationally connected to the paddle clamp base (21) and the paddle clamp upper cover (22); the damping device comprises a shell (31) clamped between the paddle clamp base (21) and the fixed ends (11) and fixedly connected to the paddle clamp base (21), and a damping assembly mounted on the shell (31); and the connecting shafts (33) penetrate the damping assembly and are fixedly connected to the damping assembly. In the folding paddle structure (10), the resistance borne by the paddles (1) is adjusted by means of the damping assembly, such that vibrations caused by the change in the direction of rotation of the paddles (1) is prevented from being transmitted to a fuselage (20), and vibrations of an electric motor (40) are not transmitted to the paddles (1) after being transmitted to the paddle clamp base (21).

Description

Folding propeller mechanism and unmanned aerial vehicle

This application claims the priority of the Chinese patent application filed with the Chinese Patent Office, the application number is 201911149823.X, and the application name is "folding propeller mechanism and unmanned aerial vehicle" on November 21, 2019. The entire content of the patent application is incorporated herein by reference. Applying.

Technical field

The invention relates to the field of unmanned aerial vehicles, in particular to a folding propeller mechanism and an unmanned aerial vehicle.

Background technique

The propeller is an important part of the multi-rotor UAV's power system. The rotors of the early multi-rotor UAVs were mostly integral fixed double-blade propellers. Later, due to the safety and space considerations of transportation and storage, they began to adopt the current mainstream The design of portable foldable paddle.

Generally, a folding propeller usually uses a propeller clamp as a connecting member, and connects two single-sided propeller blades in the form of a rotating pair, and then fixes the propeller clamp on the rotating part of the outer rotor motor. Its basic working principle is as follows: the rotation of the motor during takeoff causes the blades to be thrown away from the double-blade overlapping state through the action of inertia, and the speed is large enough to make the blades work normally after unfolding under the action of centrifugal force to provide power for the aircraft.

Whether it is an integrally formed fixed double-blade propeller or a foldable propeller, depending on the vibration mode of the blade design, there will be varying degrees of vibration during the normal operation of the blade. Not only that, the motor itself is also one of the main vibration sources of rotary-wing UAVs. In fact, on the one hand, we do not want the vibration of the rotor to be transmitted to the fuselage, which will affect the measurement accuracy of the built-in inertial navigation system of the fuselage. On the other hand, we do not want the vibration of the motor to be transmitted to the rotor blades too much. Reduce the aerodynamic efficiency and service life of the blade.

The integrally formed fixed double-blade propeller is almost rigidly connected to the motor, and there is basically no way to adjust the force transmission chain between the motor and the blade. As for the foldable propeller, the rotation pair and the accompanying gap appear in the force transmission chain between the motor and the blade, which is equivalent to introducing a damping link in the transmission system, and damping devices are often used in the transmission process. Vibration is filtered and attenuated in the system. The final vibration and attenuation result depends on whether the damping coefficient design of the system matches the vibration modal characteristics of the system. However, it is difficult to ensure the adjustment of damping by simply using the gap, whether it is from the design or the manufacturing process. Therefore, in order to achieve controllable damping design and parameter adjustment of the force transmission channel between the motor and the blade to achieve the purpose of damping, other methods need to be introduced.

This patent uses fluid viscosity and fluid resistance changes as the basic principle, and realizes the controllable adjustment of the damping of the foldable propeller rotating pair by controlling the fluid viscosity and the actual area of the damping baffle, thereby improving the damping efficiency, improving design efficiency, and reducing trial production. The iterative cost of the process.

Summary of the invention

In order to overcome the shortcomings of the prior art, the purpose of the present invention is to provide a folding propeller mechanism with a controllable adjustment of the damping of the rotating pair.

One of the objectives of the present invention is achieved by adopting the following technical solutions:

A folding propeller mechanism is provided, comprising a propeller clamp base, a propeller clamp upper cover, a blade, a connecting shaft, and a damping device for forming resistance to the rotation of the propeller blade, the propeller clamp upper cover and the propeller clamp base Are arranged at intervals, the paddles include a fixed end and a free end, the fixed end is clamped between the paddle clamp base and the paddle clamp upper cover, and the connecting shaft passes through the paddle clamp base and the In the blade and the upper cover of the paddle clamp, the connecting shaft is fixedly connected with the fixed end, the connecting shaft is rotatably connected with the paddle clamp base and the upper cover of the paddle clamp, and the damper includes a clamp A housing provided between the paddle clamp base and the fixed end and fixedly connected to the paddle clamp base and a damping assembly installed on the housing, the connecting shaft passes through the damping assembly and is connected to the damping assembly The components are fixedly connected.

Further, the damping assembly includes an impeller rotatably connected to the housing and a damping fluid provided in the housing, a through hole is provided in the middle of the housing, and the impeller includes an impeller penetrating through the through hole and connecting to the through hole. A wheel disc rotatably connected with the casing and a plurality of blades arranged around the outer side wall of the wheel disc at intervals, and the blades are immersed in the damping liquid.

Further, the viscosity parameter of the damping fluid is adjustable.

Further, the wheel disc includes a main body and a driving mechanism installed inside the main body, one end of the blade penetrates the main body and is connected with the driving mechanism, and the driving mechanism is used to drive the blade Rotate around its extension direction.

Further, the wheel disc protrudes from the end surface of the shell facing away from the paddle clamp base.

Further, the fixed end is provided with a first shaft hole, the wheel is provided with a second shaft hole, and the outer wall of the connecting shaft is convexly provided with a limit extending in the axial direction of the connecting shaft. A positioning pin is provided on the wall surface of the first shaft hole with a first limiting groove that cooperates with the limiting pin, and the wall surface of the second shaft hole is provided with a second limiting groove that cooperates with the limiting pin. Bit slot.

Further, the end surface of the paddle clamp base facing the upper cover of the paddle clamp is provided with an accommodation groove for accommodating and fixing the housing.

Further, the upper cover of the paddle clamp is also provided with a first connecting hole, the folding paddle mechanism further includes a connecting rod protruding from the paddle clamp base, and an outer peripheral surface of the end of the connecting rod is provided The connecting rod is threaded, and the connecting rod passes through the first connecting hole and the end of the connecting rod protrudes from the upper cover of the paddle clip. The folding paddle mechanism further includes an end for connecting with the connecting rod. Nuts for threaded connections.

The present invention also provides an unmanned aerial vehicle, including a fuselage, an arm and a propeller mechanism. One end of the arm is connected to the fuselage and the other end is connected to the propeller mechanism. The propeller mechanism includes a motor and a propeller mechanism as described above. In the folding paddle mechanism, the folding paddle mechanism is connected to the output shaft of the motor.

Compared with the prior art, the present invention has the beneficial effects that: the folding propeller mechanism provided by the present invention adjusts the resistance of the propeller blade when rotating through the damping assembly, and isolates the force transmission channel between the propeller blade and the fuselage, thereby avoiding the propeller. The vibration caused by the change of the blade rotation trend is transmitted to the fuselage, which affects the measurement accuracy of the built-in inertial navigation system of the fuselage; and after the vibration of the motor is transmitted to the propeller clamp base, it will not be transmitted to the propeller blades, and thus will not Affect the aerodynamic efficiency and service life of the blade.

Description of the drawings

Figure 1 is a schematic structural diagram of a folding paddle mechanism according to an embodiment of the present invention;

2 is a schematic structural view of another angle of the folding paddle mechanism provided by the embodiment of the present invention;

FIG. 3 is a schematic structural diagram of another angle of the folding paddle mechanism provided by the embodiment of the present invention;

4 is a schematic diagram of the structure of the blades, the liquid storage box, the turntable and the connecting shaft in the folding paddle mechanism according to the embodiment of the present invention;

Fig. 5 is a schematic structural diagram of an unmanned aerial vehicle provided by an embodiment of the present invention.

In the picture:

10. Folding propeller structure; 1. Blade; 11. Fixed end; 12. Free end; 111. First shaft hole; 112. First limit slot; 21. Propeller clamp base; 211. Third connecting hole; 212 22. The upper cover of the paddle clamp; 221, the second connecting hole; 222, the first connecting hole; 31, the shell; 311, the top plate; 312, the bottom plate; 313, the side plate; 314, the through hole; 315, Annular groove; 32, impeller; 321, disc; 322, annular flange; 323, blade; 324, second shaft hole; 325, second limit slot; 33, connecting shaft; 331, limit pin; 41. Connecting rod; 42, nut; 100, unmanned aerial vehicle; 20, fuselage; 30, arm; 40, motor.

Detailed ways

In the following, the present invention will be further described with reference to the drawings and specific implementations. It should be noted that, provided that there is no conflict, the following embodiments or technical features can be combined to form new embodiments. .

It should be noted that all directional indicators (such as up, down, left, right, front, back, top, bottom...) in the embodiments of the present invention are only used to explain in a specific posture (as shown in the accompanying drawings) If the specific posture changes, the relative positional relationship between the components will also change the directional indication accordingly.

It should also be noted that when an element is referred to as being "fixed on" or "disposed on" another element, the element may be directly on the other element or there may be a centering element at the same time. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or an intermediate element may be present at the same time.

Please refer to Figures 1 to 4, the present invention provides a folding propeller mechanism 10, applied to an unmanned aerial vehicle 100, the folding propeller mechanism 10 includes a propeller clamp upper cover 22, a propeller clamp base 21 and two blades 1, the propeller clamp upper cover 22 and the paddle clamp base 21 are spaced apart and connected by a connecting structure. Each paddle 1 includes a fixed end 11 and a free end 12. The fixed end 11 is positioned between the paddle clamp upper cover 22 and the paddle clamp base 21, and the blade 1 can be It rotates around the fixed end 11 to realize folding and unfolding. A housing 31 fixed on the paddle holder base 21 is also provided between the paddle holder upper cover 22 and the paddle holder base 21. The housing 31 includes a top plate 311, a bottom plate 312 and a connection point. The edge of the top plate 311 and the side plate 313 of the edge of the bottom plate 312, the top plate 311, the bottom plate 312 and the side plate 313 are enclosed to form a liquid storage chamber, and the damping fluid is stored in the liquid storage chamber. A cylindrical through hole 314 is formed on the housing 31. The central axis of the through hole 314 is in line with the central axis around which the blade 1 is deployed. The annular groove 315 extending in the circumferential direction of 314 is connected to the liquid storage chamber. The folding paddle mechanism 10 also includes a damping assembly. The damping assembly includes an impeller 32, which is linked with the blade 1, and the impeller 32 includes a cylindrical disk. 321 and an annular flange 322 protruding from the outer peripheral surface of the wheel 321 and extending along the circumference of the wheel 321, the wheel 321 is embedded in the groove 314, the annular flange 322 is embedded in the annular groove 315, and the ring The outer peripheral surface of the shaped flange 322 is connected with a plurality of blades 323 arranged at intervals in the circumferential direction, and the blades 323 are immersed in the damping liquid. The plate surface of the blade 323 is parallel or at an angle with the radial direction of the through hole 314, and is folded The paddle mechanism 10 also includes a connecting shaft 33 that is fixedly connected to the fixed end 11 of the paddle 1 and the wheel 321, and the two ends are respectively rotatably connected to the paddle clamp base 21 and the paddle clamp upper cover 22. When the UAV 100 takes off, the blade 1 Throw away from the overlapping state of the double blades, the speed of the blade holder base 21 is large enough to make the blade 1 work normally after unfolding under the action of centrifugal force (the blade 1 does not rotate relative to the upper cover 22 of the blade holder and the blade holder base 21), To provide power for the unmanned aerial vehicle 100, since the blade 1 is linked with the wheel 321, the rotation trend of the blade 1 is transmitted to the blade 323, and the blade 323 receives resistance in the damping fluid, thereby avoiding the change of the rotation trend of the blade 1 The incoming vibration is transmitted to the fuselage 20 so as not to affect the measurement accuracy of the inertial navigation. Also, since the blade 323 is resisted in the damping fluid, the vibration of the motor 40 will not be transmitted to the blade 1 after being transmitted to the paddle clamp base 21, so that the aerodynamic efficiency and service life of the blade 1 will not be affected.

It should be noted that the fixed connection means that the connecting shaft 33 and the fixed end 11 cannot rotate relative to each other, and does not mean that the connecting shaft 33 and the fixed end 11 are fixed together. Of course, in the application, the connecting shaft 33 and the fixed end 11 are fixed together. The above-mentioned solution can also be realized by the fixed connection. Preferably, the connecting shaft 33 and the fixed end 11 are movable in the axial direction to facilitate assembly.

In another embodiment, the housing 31 may have other forms. Specifically, the top plate 311 and the bottom plate 312 are respectively provided with perforations (not shown in the figure), and the blade 1 and the wheel 321 are completely immersed in the housing 31 and connected One side of the shaft 33 passes through the perforation on the top plate 311 and the end is rotatably connected with the upper cover 22 of the paddle clamp, and the other side of the connecting shaft 33 passes through the perforation on the bottom plate 312 and the end is rotatably connected with the paddle clamp base 21, the same The blocking effect of the damping liquid on the blade 323 can be realized.

The housing 31 is formed as a liquid storage box, and preferably the outer contour of the liquid storage box is cylindrical, and it is understandable that the annular flange 322 may not be provided.

The resistance of the blade 323 in the damping fluid can be changed by changing the fluid viscosity or water resistance of the damping fluid. The viscosity of the damping fluid can be controlled and changed. In particular, its viscosity properties can be controlled by electronically controlled physical quantities, such as voltage, Electric current can change its viscosity by applying different voltages or currents in the damping fluid. Of course, with the emergence of new materials, it can also be replaced with other materials that can be changed in a controlled manner.

The resistance of the blade 323 in the damping fluid can also be changed by changing the angle between the plate surface of the blade 323 and the radial direction of the through hole 314 by a driving mechanism (not shown in the figure). Specifically, the wheel 321 includes a main body, which drives The mechanism is installed inside the main body, the blade 323 penetrates the main body, and one end of the blade 323 located inside the main body is connected to the driving mechanism. The driving mechanism drives the blade 323 to rotate around its extending direction. The driving mechanism can be provided with a motor for each blade 323. (Not shown in the figure), a plurality of blades 323 can also be driven to rotate by a motor.

Preferably, the plurality of blades 323 are arranged at equal intervals, so that controllability is easier to achieve.

A first shaft hole 111 is opened on the fixed end 11, a second shaft hole 324 is opened in the center of the wheel 321, and the outer wall of the connecting shaft 33 is convexly provided with a limiting pin 331 extending in the axial direction. The wall surface of the first shaft hole 111 is provided with a first limiting groove 112 which cooperates with the limiting pin 331, and the wall surface of the second shaft hole 324 is provided with a second limiting groove 112 which cooperates with the limiting pin 331. Limit slot 325. Due to the mutual limiting effect of the limiting pin 331 and the first limiting slot 112 and the second limiting slot 325, the blade 1 and the connecting shaft 33 will not rotate relative to each other in the circumferential direction, and the connecting shaft 33 and the wheel 321 will not rotate relative to each other. Will be relatively rotated in the circumferential direction, so that the force of the blade 323 can be transmitted to the blade 1 through the annular flange 322, the wheel 321 and the connecting shaft 33, because the housing 31 is fixedly connected to the blade clamp base 21 , The housing 31 is fixed, and because the housing 31 limits the radial direction of the wheel 321, the wheel 321, the connecting shaft 33 and the blade 1 can be positioned in the radial direction.

The upper cover 22 of the paddle clamp is also provided with a first connecting hole 222. The connecting structure further includes a connecting rod 41 protruding from the paddle clamp base 21. The end of the connecting rod 41 has an outer peripheral surface. The connecting rod 41 passes through the first connecting hole 222 and the end of the connecting rod 41 protrudes from the upper cover 22 of the paddle clamp. The connecting structure further includes a connecting structure for connecting with the The end of the rod 41 is screwed with a nut 42.

Preferably, the connecting rod 41 is provided in the middle position of the paddle clamp base 21. In other embodiments, multiple connecting rods 41 may be provided, and threaded holes may be opened on the end surface of the connecting rod 41, and the connecting rod 41 and the paddle may be connected by screws.夹上盖22。 Clip on the cover 22.

The paddle clip upper cover 22 is provided with a second connecting hole 221 facing the end surface of the paddle clip base 21, the connecting shaft 33 sequentially penetrates the shaft hole 324 and the through hole 111, and the end is embedded in In the second connecting hole 221, preferably both ends of the connecting shaft 33 are respectively embedded in the second connecting hole 221 of the paddle clip upper cover 22 and the third connecting hole 211 of the paddle clip base 21. Only the first connecting hole 221 may be opened, or only the second connecting hole 211 may be opened.

The paddle clamp upper cover 22 and the paddle clamp base 21 clamp the connecting shaft 33 therebetween, so as to limit the blade 1 in the axial direction.

The end surface of the paddle clamp base 21 facing the upper cover 22 is provided with an accommodation groove 212 for accommodating and fixing the liquid storage box 31; The groove wall surface is glued or tightly fitted, of course, it can be connected by other methods, such as welding, ultrasonic connection or screw connection.

The main idea of the present invention is to introduce a damping adjustable structure into the traditional foldable design, and realize the adjustment of the damping coefficient by using the controllable change of fluid viscosity and the change of fluid resistance. It is composed of a casing 31 and blades 323 distributed in a circular array. The casing 31 stores a fluid whose viscosity can be changed in a controlled manner. The stored fluid is required to have the following characteristics: its viscosity property is related to other electronically controllable physical quantities, such as voltage, current, etc. , That is, it is required to use electrical physical quantities to adjust the viscosity of the special fluid. Secondly, similar to the boating principle, the movement (or movement trend) of the blade 323 in the fluid will be subject to the flow resistance from the fluid, and the baffle and the fluid The greater the contact area in the direction of relative movement, the greater the resistance. For this reason, the blade 323 is designed to leave the controllable degree of freedom moving in the axial direction, and the contact area of the baffle in the direction of the relative movement of the fluid can also be controlled, thereby controlling the fluid resistance of the baffle during rotation.

In summary, in the folding propeller mechanism 10 provided by the present invention, the resistance of the blade 323 in the damping fluid is controllable, and the resistance of the damping baffle 323 is transmitted to the blade 1 through the wheel 32, thereby preventing the rotation of the blade 1 The vibration caused by the change of trend is transmitted to the fuselage 20, which affects the measurement accuracy of the inertial navigation; and also because the blade 323 receives resistance in the damping fluid, the vibration of the motor 40 is transmitted to the propeller clamp base 21, and will not be transmitted to the propeller. On the blade 1, so as not to affect the aerodynamic efficiency and service life of the blade 1, as much as possible, the transmission of the vibration of the motor 40 to the blade 1 and the transmission of the vibration of the blade 1 to the fuselage 20 are attenuated, and the fluid viscosity and water resistance are changed. As a basic principle, the controllable adjustment of the damping of the foldable propeller rotating pair is achieved by controlling the fluid viscosity and the actual area of action of the blades 323, so as to realize the damping efficiency, improve the design efficiency, and reduce the iterative cost in the trial production process.

5, the present invention also protects an unmanned aerial vehicle 100, including a fuselage 20, an arm 30, and a propeller mechanism. One end of the arm 30 is connected to the fuselage 20, and the other end is connected to the propeller mechanism. The connection is characterized in that the propeller mechanism includes a motor 40 and the folding propeller mechanism 10 as described above, and the folding propeller mechanism 10 is connected to the output shaft of the motor 40.

The foregoing embodiments are only preferred embodiments of the present invention, and cannot be used to limit the scope of protection of the present invention. Any insubstantial changes and substitutions made by those skilled in the art on the basis of the present invention belong to the present invention. The scope of protection required.

Claims

A folding propeller mechanism, characterized in that it comprises a propeller clamp base, a propeller clamp upper cover, a blade, a connecting shaft, and a damping device used to form resistance to the rotation of the propeller blade, the propeller clamp upper cover and the The paddle clamp bases are arranged at intervals, the paddle blades include a fixed end and a free end, the fixed end is clamped between the paddle clamp base and the upper cover of the paddle clamp, and the connecting shaft penetrates through the paddle clamp In the base, the blade and the upper cover of the paddle clamp, the connecting shaft is fixedly connected to the fixed end, the connecting shaft is rotatably connected with the paddle clamp base and the upper cover of the paddle clamp, and the damping The device includes a housing clamped between the paddle clamp base and the fixed end and fixedly connected to the paddle clamp base, and a damping component installed on the housing. The connecting shaft passes through the damping component and is connected to the The damping component is fixedly connected.
The folding propeller mechanism according to claim 1, wherein the damping assembly includes an impeller rotatably connected to the housing and a damping fluid provided in the housing, and a through hole is provided in the middle of the housing, so The impeller includes a wheel disc pierced through the through hole and rotatably connected with the casing, and a plurality of blades arranged around the outer side wall of the wheel disc at intervals, and the blades are immersed in the damping liquid.
The folding propeller mechanism of claim 1, wherein the viscosity parameter of the damping fluid is adjustable.
The folding paddle mechanism according to claim 2, wherein the wheel disc comprises a main body and a driving mechanism installed inside the main body, and one end of the blade penetrates the main body and is connected to the driving mechanism. Connected, the drive mechanism is used to drive the blade to rotate around its extending direction.
The folding paddle mechanism according to claim 2, wherein the wheel disc protrudes from an end surface of the housing facing away from the paddle clamp base.
The folding paddle mechanism of claim 5, wherein the fixed end is provided with a first shaft hole, the wheel is provided with a second shaft hole, and the outer wall of the connecting shaft is convexly provided A limiting pin extending along the axial direction of the connecting shaft, a first limiting groove matching with the limiting pin is formed on the wall surface of the first shaft hole, and a wall surface of the second shaft hole is provided There is a second limiting groove matched with the limiting pin.
The folding paddle mechanism according to claim 2, wherein the end surface of the paddle clamp base facing the upper cover of the paddle clamp is provided with an accommodation groove for accommodating and fixing the housing.
The folding paddle mechanism of claim 1, wherein the upper cover of the paddle clip is further provided with a first connecting hole, and the folding paddle mechanism further comprises a connecting rod protruding from the base of the paddle clip, The outer peripheral surface of the end of the connecting rod is provided with threads, the connecting rod passes through the first connecting hole and the end of the connecting rod protrudes from the upper cover of the paddle clip, the folding paddle mechanism It also includes a nut for threaded connection with the end of the connecting rod.
An unmanned aerial vehicle, comprising a fuselage, an arm and a propeller mechanism, one end of the arm is connected to the fuselage, and the other end is connected to the propeller mechanism, characterized in that the propeller mechanism includes a motor and The folding paddle mechanism according to any one of claims 1-8, which is connected to the output shaft of the motor.