Special motor for unmanned aerial vehicle and control system thereof

Abstract

The invention discloses a special motor for an unmanned aerial vehicle and a control system thereof, and relates to the technical field of unmanned aerial vehicle motors, the special motor specifically comprises an unmanned aerial vehicle body and a plurality of top motor assemblies installed on the unmanned aerial vehicle body, and output structures of the motor assemblies are in transmission connection with propeller assemblies. The motor assembly comprises a brushless direct current motor and an outer protection shell arranged on the outer side of a shell of the brushless direct current motor in a sleeving mode, and the outer protection shell is fixed to the top face of the unmanned aerial vehicle body. A second temperature sensor is combined with an air cooling mechanism formed by two air cooling ring pipes, a second communicating pipe, a first branch pipe, a second branch pipe and a flow guide assembly, and a circulating liquid cooling mechanism formed by two liquid cooling ring pipes, a first communicating pipe, a backflow electromagnetic valve pipe, an output electromagnetic valve pipe and a cooling oil pump assembly for use; brushless direct current motors with different heat dissipation requirements can carry out heat dissipation operation one by one, every two brushless direct current motors are matched for heat dissipation operation, and the three brushless direct current motors carry out heat dissipation operation synchronously, so that the heat dissipation requirements of the brushless direct current motors are fully met.

Description

TECHNICAL FIELD

[0001] The application relates to the field of unmanned aerial vehicle motors, in particular to a special motor for unmanned aerial vehicles and a control system thereof. BACKGROUND

[0002] An unmanned aerial vehicle, full name unmanned aerial vehicle, is a kind of unmanned aircraft controlled by radio remote control equipment or self-programming control device, which is mainly composed of a fuselage, a power system formed by a special motor, a control system, a communication system and a task load, and there are various types of unmanned aerial vehicles, which can be divided into military unmanned aerial vehicles and civil unmanned aerial vehicles according to the use, wherein the civil unmanned aerial vehicles are widely used in many fields, for example, in film and television shooting, the unmanned aerial vehicle can provide a unique aerial view and shoot a breathtaking picture; in the field of agriculture, it can carry out pesticide spraying and crop monitoring to improve the efficiency of agricultural production; in the field of surveying and mapping, it can quickly and accurately obtain geographic information data; in the logistics industry, it explores the efficient distribution mode of goods, etc.

[0003] In recent years, with the further use of unmanned aerial vehicle technology, the shortcomings existing in the hardware structure of the unmanned aerial vehicle begin to limit the upper limit of its use performance, for example, the brushless DC motor used in the existing unmanned aerial vehicle can maintain the energy conversion efficiency in the high efficient range of 80%-95%, but with the extension of use time, if not cooled in time, the service life of the brushless DC motor will also decrease, and although the existing technology discloses the technical solutions of air cooling or circulating liquid cooling, the performance upper limit is relatively low, especially the circulating liquid cooling, although the early effect is remarkable, but with the occurrence of the same temperature phenomenon, the cooling effect will decrease sharply. SUMMARY

[0004] The application provides a special motor for unmanned aerial vehicles and a control system thereof, which solves the technical problems in the background art.

[0005] In order to achieve the above purpose, the application adopts the following technical scheme: a special motor for unmanned aerial vehicles, comprising a unmanned aerial vehicle body, a plurality of top motor assemblies installed on the unmanned aerial vehicle body, an output structure of the motor assembly being drivingly connected with a propeller assembly, the motor assembly comprising a brushless DC motor and an outer protective shell sleeved outside the brushless DC motor shell, the outer protective shell being fixed on the top surface of the unmanned aerial vehicle body, and an annular accommodation space being formed between the inner wall of the outer protective shell and the surface of the brushless DC motor shell.

[0006] The surface of the brushless DC motor housing is fitted with two liquid cooling ring tubes, and the two liquid cooling ring tubes are connected by a first connecting pipe. The bottom front and rear ends of the bottom of the lowest liquid cooling ring tube are respectively fitted with a return solenoid valve tube and an output solenoid valve tube. The middle part of the UAV body is fitted with a cooling oil pump delivery assembly, which is connected to the return solenoid valve tube and the output solenoid valve tube and can circulate and deliver cooling oil to the cooling flow channel formed by the two liquid cooling ring tubes and the first connecting pipe through the return solenoid valve tube and the output solenoid valve tube to circulate and cool the brushless DC motor.

[0007] Both liquid-cooled loops are fitted with air-cooled loops, and a second connecting pipe is installed between the two air-cooled loops. The bottom of the lowest air-cooled loop is connected to a first branch pipe and a second branch pipe on both sides. The bottom of the UAV body is provided with a flow guide component that can communicate with the first branch pipe and the second branch pipe. When the flow guide component is in the open state, it can guide the outside cold air through the first branch pipe and the second branch pipe into the auxiliary flow channel formed by the two air-cooled loops and the second connecting pipe.

[0008] Preferably, the output end of the brushless DC motor can penetrate the top structure of the outer protective shell and be connected to the middle of the propeller assembly for transmission. A sealing ring is nested between the output end of the brushless DC motor and the fitting part of the top structure of the outer protective shell. A first temperature sensor is connected to the bottom of the brushless DC motor housing, and an auxiliary sleeve installed on the top shell surface of the UAV body is fixed on the bottom surface of the housing of the first temperature sensor.

[0009] Preferably, the cooling oil pump assembly includes a cooling oil box, a water pump, an annular pipe, and an auxiliary support. The surface of the cooling oil box is provided with a clearance groove, and a fixing seat is installed between the inner wall of the clearance groove and the surface of the water pump housing. The output end and input end of the water pump are respectively fitted inside the annular pipe and the bottom inner side of the cooling oil box. One end of the return solenoid valve pipe is connected to the cooling oil box, and one end of the output solenoid valve pipe is connected to the annular pipe.

[0010] Preferably, the auxiliary support includes a threaded rod, one end of which is fixed to the inner wall of the bottom of the UAV body, and the other end of which is engaged with a linkage sleeve plate fixed to the surface of the cooling oil box. The other end of the threaded rod is threaded with two limiting nuts, and the two limiting nuts can clamp and limit the linkage sleeve plate during the spiral locking process with the threaded rod.

[0011] Preferably, the airflow guiding assembly includes an auxiliary cylinder. The top two sides of the auxiliary cylinder are respectively fitted to the bottom ends of the second branch pipe and the bottom ends of the first branch pipe. The top surface of the auxiliary cylinder is fixedly connected to the outer surface of the bottom of the UAV body. The bottom structure of the auxiliary cylinder has an air inlet, and the air inlet is covered with a sealing plate. An electromagnet is fixedly sleeved on the inner side of the middle part of the auxiliary cylinder. The electromagnet can open and adjust the sealing plate by magnetic repulsion, so that cold air in the environment can enter the interior of the auxiliary cylinder.

[0012] Preferably, the sealing plate includes an iron cover plate, a guide rod, and a spring. One end of the guide rod is fixed to the surface of the top of the iron cover plate, and the other end of the guide rod is fitted inside the auxiliary cylinder. The spring is fitted to the outside of the other end of the guide rod, and the two ends of the spring are respectively fixed to the inner wall of the bottom of the auxiliary cylinder and the surface of the other end of the guide rod. When the spring is not compressed, it elastically pulls the iron cover plate to cover and seal the air inlet.

[0013] Preferably, a second temperature sensor is fixed to the surface of the brushless DC motor housing, and one end of the second temperature sensor penetrates through the outer protective shell and extends to the outside of the outer protective shell. The other end of the second temperature sensor is attached to the surface of the liquid cooling ring tube. The fitting area between the second temperature sensor and the outer protective shell is filled with strong epoxy glue for sealing.

[0014] Preferably, a self-cleaning component is provided between one end of the return solenoid valve tube and the cooling oil box. The self-cleaning component includes a semi-open cylinder, a sealing rod, and a transition cylinder. One end of the semi-open cylinder is fixedly sleeved with the shell at the bottom of the UAV body and extends to the outer side of the bottom of the UAV body. One end of the sealing rod and the transition cylinder are both snapped into the inside of the semi-open cylinder. An annular filter screen is nested and fixed between the surface of one end of the sealing rod and the inner side of the bottom of the transition cylinder. The inner wall of the bottom of the semi-open cylinder is provided with an internal thread. The surface of the other end of the sealing rod is provided with an external thread. The other end of the sealing rod can be detachably connected to the semi-open cylinder through the helical engagement of the external thread and the internal thread.

[0015] The other end of the sealing rod is fitted with a leak-proof sealing ring that can fill and seal the gap between the sealing rod and the inner wall of the semi-open cylinder, and a transition pipe is installed between the bottom of one end of the semi-open cylinder and the cooling oil box.

[0016] Preferably, a second temperature sensor is fixedly sleeved inside the other end of the semi-open cylinder, and an assembly groove is opened inside the other end of the sealing rod, and a torsion rod is fixedly sleeved inside the assembly groove.

[0017] Preferably, the control system includes a flight control computing processor, a signal output unit, an electronic speed controller processing unit, a motor drive unit, a battery module, and a motor temperature monitoring unit composed of a first temperature sensor and a second temperature sensor. The control system is electrically connected to several brushless DC motors via wires.

[0018] The present invention has the following beneficial effects:

[0019] 1. By combining the second temperature sensor with the air-cooling mechanism formed by two air-cooled ring pipes, a second connecting pipe, a first branch pipe, a second branch pipe, and a flow guiding component, and the circulating liquid-cooling mechanism formed by two liquid-cooled ring pipes, a first connecting pipe, a return solenoid valve pipe, an output solenoid valve pipe, and a cooling oil pump assembly, the device can perform heat dissipation operations one by one, two in combination, or all three simultaneously when facing brushless DC motors with different heat dissipation requirements. This fully meets the heat dissipation requirements of the brushless DC motor while maintaining its continuous and efficient transmission effect, further optimizing the overall performance of the device.

[0020] 2. By using the self-cleaning component as an extended technical means, based on the structure of the circulating liquid cooling mechanism, the filter space of its own structure can be combined with the return path of the return solenoid valve pipe in the circulating liquid cooling mechanism. After further combination, the filter space can filter out and temporarily store the oxidation deposits generated by the reciprocating heat absorption in the cooling oil returned by the return solenoid valve pipe, reducing the probability of blockage in the subsequent pipeline structure of the circulating liquid cooling mechanism and extending the service life of the cooling oil.

[0021] 3. The control system set up in this invention can calculate the thrust required by the four brushless DC motors to maintain or change the current attitude based on GPS, IMU, remote controller signals, etc., through the flight control computing processor. The ESC processing unit will monitor the back EMF and phase current of the brushless DC motors in real time and feed them back to the FOC algorithm to form a closed loop, ensuring that the brushless DC motors operate strictly according to the instructions and can respond quickly to load changes. Attached Figure Description

[0022] Figure 1 This is a front view schematic diagram of the structure of the present invention;

[0023] Figure 2 This is a top view of the cooling oil pump delivery assembly in the structure of the present invention;

[0024] Figure 3 This is a three-dimensional schematic diagram of the cooling oil pump delivery assembly in the structure of the present invention;

[0025] Figure 4 This is a left-side schematic diagram of the cooling oil pump delivery assembly in the structure of the present invention;

[0026] Figure 5 This is a cross-sectional schematic diagram of the flow guiding component in the structure of the present invention;

[0027] Figure 6 This is a three-dimensional schematic diagram of the flow guiding component in the structure of the present invention;

[0028] Figure 7 This is a top view schematic diagram of the first temperature sensor in the structure of the present invention;

[0029] Figure 8 This is a cross-sectional schematic diagram of the self-cleaning component in the structure of the present invention;

[0030] Figure 9 This is a top view of the annular filter screen in the structure of the present invention;

[0031] Figure 10 This is a schematic diagram of the control system of the present invention.

[0032] In the diagram: 1. UAV body; 2. Brushless DC motor; 3. Propeller assembly; 4. Cooling oil box; 5. Water pump; 6. Annular pipe; 7. Auxiliary support; 8. Liquid-cooled annular pipe; 9. First connecting pipe; 10. Return solenoid valve pipe; 11. Output solenoid valve pipe; 12. Air-cooled annular pipe; 13. Second connecting pipe; 14. First branch pipe; 15. Second branch pipe; 16. Auxiliary cylinder; 17. Iron cover plate; 18. Guide rod; 19. Spring; 20. Electromagnet; 21. First temperature sensor; 22. Auxiliary sleeve; 23. Outer protective shell; 24. Self-cleaning component; 241. Semi-open cylinder; 242. Sealing rod; 243. Transition cylinder; 244. Torsion bar; 245. Annular filter plate; 246. Transition pipe; 247. Leak-proof sealing ring; 25. Second temperature sensor. Detailed Implementation

[0033] The technical solution of the present invention will be clearly and completely described below with reference to preferred embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0034] like Figures 1-7 A special motor for drones includes a drone body 1 and several top motor assemblies installed on the drone body 1. The output structure of the motor assembly is connected to a propeller assembly 3. The motor assembly includes a brushless DC motor 2 and an outer protective shell 23 fitted on the outside of the brushless DC motor 2 housing. The outer protective shell 23 is fixed to the top surface of the drone body 1, and an annular clearance space is formed between the inner wall of the outer protective shell 23 and the surface of the brushless DC motor 2 housing.

[0035] The surface of the brushless DC motor 2 is fitted with two liquid cooling ring pipes 8, and the two liquid cooling ring pipes 8 are connected to a first connecting pipe 9. The bottom front and rear ends of the liquid cooling ring pipe 8 located at the bottom are respectively fitted with a return solenoid valve pipe 10 and an output solenoid valve pipe 11. The middle part of the UAV body 1 is fitted with a cooling oil pump delivery assembly, and the cooling oil pump delivery assembly is connected to the return solenoid valve pipe 10 and the output solenoid valve pipe 11. It can circulate and deliver cooling oil to the cooling flow channel formed by the two liquid cooling ring pipes 8 and the first connecting pipe 9 through the return solenoid valve pipe 10 and the output solenoid valve pipe 11 to circulate and cool the brushless DC motor 2.

[0036] Both liquid-cooled ring pipes 8 are internally fitted with air-cooled ring pipes 12, and a second connecting pipe 13 is installed between the two air-cooled ring pipes 12. A first branch pipe 14 and a second branch pipe 15 are respectively connected to the bottom of the lowest air-cooled ring pipe 12. The bottom of the UAV body 1 is provided with a flow guide component that can communicate with the first branch pipe 14 and the second branch pipe 15. When the flow guide component is open, it can guide outside cold air through the first branch pipe 14 and the second branch pipe 15 into the auxiliary flow channel formed by the two air-cooled ring pipes 12 and the second connecting pipe 13. The output end of the brushless DC motor 2 can penetrate the outer casing. The top structure of the protective shell 23 can be connected to the middle of the propeller assembly 3, and a sealing ring is nested between the output end of the brushless DC motor 2 and the fitting part of the top structure of the outer protective shell 23, thereby ensuring the sealing effect of the fitting connection between the brushless DC motor 2 and the outer protective shell 23. The bottom of the shell of the brushless DC motor 2 is connected to a first temperature sensor 21, and an auxiliary sleeve 22 installed on the top shell surface of the UAV body 1 is fixed on the shell surface at the bottom of the first temperature sensor 21. The first temperature sensor 21 can realize feedback of the operating temperature of the brushless DC motor 2, providing data conditions for subsequent control.

[0037] The brushless DC motor 2 has a second temperature sensor 25 fixed on its housing surface. One end of the second temperature sensor 25 penetrates the outer protective shell 23 and extends to the outside of the outer protective shell 23. The other end of the second temperature sensor 25 is attached to the surface of the liquid cooling ring tube 8. The fitting part between the second temperature sensor 25 and the outer protective shell 23 is filled with strong epoxy glue for sealing, thereby further increasing the technical means and approach for heat dissipation of the brushless DC motor 2.

[0038] The cooling oil pump assembly includes a cooling oil box 4, a water pump 5, an annular pipe 6, and an auxiliary support 7. The surface of the cooling oil box 4 is provided with a clearance groove, and a fixing seat is installed between the inner wall of the clearance groove and the housing surface of the water pump 5. The output end and the input end of the water pump 5 are respectively fitted inside the annular pipe 6 and the bottom inner side of the cooling oil box 4. One end of the return solenoid valve pipe 10 is connected to the cooling oil box 4, and one end of the output solenoid valve pipe 11 is connected to the annular pipe 6.

[0039] The airflow guiding assembly includes an auxiliary cylinder 16. The top two sides of the auxiliary cylinder 16 are respectively fitted to the bottom ends of the second branch pipe 15 and the first branch pipe 14. The top surface of the auxiliary cylinder 16 is fixedly connected to the outer surface of the bottom of the UAV body 1. The bottom structure of the auxiliary cylinder 16 has an air inlet, which is covered by a sealing plate. An electromagnet 20 is fixedly fitted onto the inner side of the middle part of the auxiliary cylinder 16. The electromagnet 20 can open and adjust the sealing plate by magnetic repulsion, allowing cold air from the environment to enter the interior of the auxiliary cylinder 16. The sealing plate includes an iron cover plate 17, a guide rod 18, and a spring 19. One end of the guide rod 18 is fixed to the top of the iron cover plate 17. On the surface of the auxiliary tube 16, the other end of the guide rod 18 is fitted inside the auxiliary tube 16, the spring 19 is fitted on the outside of the other end of the guide rod 18, and the two ends of the spring 19 are respectively fixed to the inner wall of the bottom of the auxiliary tube 16 and the surface of the other end of the guide rod 18. When the spring 19 is not compressed, it elastically pulls the iron cover plate 17 to cover and seal the air inlet. The auxiliary bracket 7 includes a threaded rod. One end of the threaded rod is fixed to the inner wall of the bottom of the UAV body 1, and the other end of the threaded rod is engaged with a linkage sleeve plate fixed to the surface of the cooling oil box 4. The surface of the other end of the threaded rod is threaded with two limit nuts, and the two limit nuts can clamp and limit the linkage sleeve plate during the spiral locking process with the threaded rod.

[0040] In use, considering the heat dissipation problem of the brushless DC motor 2 during long-term operation, the first temperature sensor 21 is used to detect the brushless DC motor 2 in real time. In the initial stage of heat generation of the brushless DC motor 2, multiple second temperature sensors 25 are provided and the heat conduction effect of the second temperature sensor 25 is used to initially accelerate the self-heating speed of the brushless DC motor 2.

[0041] When the first temperature sensor 21 detects that the excess heat of the brushless DC motor 2, after being cooled by multiple second temperature sensors 25, still reaches the preset first gradient range, the electromagnet 20 is activated. The electromagnet 20 generates a magnetic force that repels the iron cover plate 17, thereby forcing the iron cover plate 17 away from the auxiliary cylinder 16 to make room for the air inlet. In conjunction with the UAV body 1 in flight, cold air from the outside will enter the interior of the auxiliary cylinder 16 through the air inlet. Then, the cold air enters the air-cooling channel formed by the second branch pipe 15, the two air-cooling ring pipes 12, the second connecting pipe 13, and the first branch pipe 14 and continues for a certain period of time. Thus, the cooling oil inside the two liquid-cooling ring pipes 8 and the second temperature sensor 25 perform a dual heat conduction cooling effect on the brushless DC motor 2, and the heat conducted out continuously exchanges heat with the cold air in the air-cooling channel, fully ensuring the cooling effect and the continuous effect.

[0042] When the first temperature sensor 21 detects that the excess heat of the brushless DC motor 2 still reaches the preset second gradient range after the above-mentioned dual heat conduction cooling effect, the water pump 5 is started and the solenoid valve inside the return solenoid valve tube 10 and the solenoid valve inside the output solenoid valve tube 11 are opened. The water pump 5 pumps the cooling oil inside the cooling oil box 4 to the inside of the annular tube 6. Then, the annular tube 6 divides the oil into the inside of the four output solenoid valve tubes 11. The output solenoid valve tubes 11 guide the cooling oil to the liquid cooling flow channel formed by the two liquid cooling annular tubes 8 and the first connecting tube 9. The cooling oil is further improved by liquid cooling heat conduction to increase the cooling speed of the brushless DC motor 2. The used cooling oil flows back to the inside of the cooling oil box 4 through the return solenoid valve tube 10, thereby realizing the triple heat conduction cooling effect.

[0043] Furthermore, during the liquid cooling process, the electromagnet 20 remains on, which allows the cold air to assist in cooling the circulating cooling oil, thus creating favorable conditions for continued use.

[0044] like Figures 1-9 A self-cleaning component 24 is provided between one end of the return solenoid valve pipe 10 and the cooling oil box 4. The self-cleaning component 24 includes a semi-open cylinder 241, a sealing rod 242, and a transition cylinder 243. One end of the semi-open cylinder 241 is fixedly sleeved with the shell at the bottom of the UAV body 1 and extends to the outer side of the bottom of the UAV body 1. One end of the sealing rod 242 and the transition cylinder 243 are both snapped into the inside of the semi-open cylinder 241, and an annular filter screen plate 245 is nested and fixed between the surface of one end of the sealing rod 242 and the inner side of the bottom of the transition cylinder 243. The inner wall of the bottom of the semi-open cylinder 241 is provided with internal threads. The other end of the sealing rod 242 has an external thread, and the other end of the sealing rod 242 can be detachably connected to the semi-open cylinder 241 through the helical engagement of the external thread and the internal thread. The other end of the sealing rod 242 is fitted with a leak-proof sealing ring 247 that can fill and seal the gap between the sealing rod 242 and the inner wall of the semi-open cylinder 241. A transition tube 246 is installed between the bottom of one end of the semi-open cylinder 241 and the cooling oil box 4. A second temperature sensor 25 is fixedly sleeved in the end of the other end of the semi-open cylinder 241. An assembly groove is opened in the end of the other end of the sealing rod 242, and a torsion rod 244 is fixedly sleeved in the assembly groove.

[0045] During use, considering that the cooling oil in the cooling oil box 4 is prone to oxidation and precipitation after repeated heat absorption and dissipation, which reduces its service life, the semi-open cylinder 241, sealing rod 242, transition cylinder 243, and annular filter screen 245 form a filtration space in the return path of the return solenoid valve pipe 10. This allows for the filtration and temporary storage of oxidation deposits without interfering with the return transport effect of the return solenoid valve pipe 10. After the cooling oil has been used for a certain period of time, when the whole device is idle, the solenoid valve inside the return solenoid valve pipe 10 and the solenoid valve inside the output solenoid valve pipe 11 can be closed. The torsion rod 244 can be squeezed and the sealing rod 242 can be turned with force to remove the sealing rod 242 from the inside of the semi-open cylinder 241. Then, the oxidation deposits collected inside the assembly formed by the sealing rod 242, transition cylinder 243, and annular filter screen 245 can be poured out and cleaned. After completion, the sealing rod 242 can be reset and locked, thereby extending the service life of the cooling oil in the cooling oil box 4.

[0046] In practical use, the temperature data detected by the second temperature sensor 25 can be used as a reference for the temperature data output by the first temperature sensor 21, thereby verifying the accuracy of the data output by the first temperature sensor 21. Furthermore, in the process of further use, the monitoring of the cooling oil by the second temperature sensor 25 can also provide users with data references reflecting the cooling status of the brushless DC motor 2.

[0047] like Figure 10 The control system includes a flight control computing processor, a signal output unit, an electronic speed controller processing unit, a motor drive unit, a battery module, and a motor temperature monitoring unit composed of a first temperature sensor 21 and a second temperature sensor 25. The control system is electrically connected to several brushless DC motors 2 via wires.

[0048] In use, the flight control computing processor can calculate the thrust required by each of the four brushless DC motors to maintain or change the current attitude based on GPS, IMU inertial measurement unit, remote controller signals, etc. The signal output unit provides the flight control computing processor with PWM signals or more modern digital protocols such as DShot for communication channels, so that the flight control computing processor can smoothly send the thrust command to the ESC processing unit. The DShot protocol has the advantages of strong anti-interference and low latency.

[0049] The MCU microcontroller in the ESC processing unit can interpret the thrust command issued by the flight control computing processor. Then, through the FOC algorithm, it calculates the amplitude and frequency of the three-phase current that should be output to the brushless DC motor 2. The MOSFET bridge power switch inside the motor drive unit switches quickly according to the MCU's instructions, converting the DC power from the battery module into the required three-phase AC power to drive the brushless DC motor 2 to rotate. The ESC processing unit will monitor the back EMF and phase current of the brushless DC motor 2 in real time and feed it back to the FOC algorithm to form a closed loop, ensuring that the brushless DC motor 2 operates strictly according to the instructions and can respond quickly to load changes.

[0050] The motor temperature monitoring unit uses the second temperature sensor 25 and the first temperature sensor 21 to indirectly or directly monitor the temperature of the brushless DC motor 2, and then links with the above-mentioned cooling structure to perform heat dissipation and cooling treatment on the brushless DC motor 2 at different temperatures.

[0051] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention. The invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A motor for unmanned aerial vehicles (UAVs), comprising a UAV body (1) and a plurality of top motor assemblies mounted on the UAV body (1), wherein the output structure of the motor assembly is drivenly connected to a propeller assembly (3), characterized in that: The motor assembly includes a brushless DC motor (2) and an outer protective shell (23) fitted on the outside of the brushless DC motor (2) housing. The outer protective shell (23) is fixed to the top surface of the UAV body (1), and an annular clearance space is formed between the inner wall of the outer protective shell (23) and the housing surface of the brushless DC motor (2). The surface of the brushless DC motor (2) is fitted with two liquid cooling ring pipes (8), and the two liquid cooling ring pipes (8) are equipped with a first connecting pipe (9). The bottom front and rear ends of the liquid cooling ring pipe (8) located at the bottom are respectively fitted with a return solenoid valve pipe (10) and an output solenoid valve pipe (11). The middle part of the UAV body (1) is fitted with a cooling oil pump delivery assembly, and the cooling oil pump delivery assembly is connected to the return solenoid valve pipe (10) and the output solenoid valve pipe (11) and can circulate and deliver cooling oil to the cooling channel formed by the two liquid cooling ring pipes (8) and the first connecting pipe (9) through the return solenoid valve pipe (10) and the output solenoid valve pipe (11) to circulate and cool the brushless DC motor (2). Both liquid-cooled ring pipes (8) are fitted with air-cooled ring pipes (12), and a second connecting pipe (13) is installed between the two air-cooled ring pipes (12). The bottom of the lowest air-cooled ring pipe (12) is connected to a first branch pipe (14) and a second branch pipe (15) respectively. The bottom of the UAV body (1) is provided with a flow guide component that can communicate with the first branch pipe (14) and the second branch pipe (15).

2. The UAV-specific motor according to claim 1, characterized in that: The output end of the brushless DC motor (2) can penetrate the top structure of the outer protective shell (23) and can be connected to the middle of the propeller assembly (3). A sealing ring is nested between the output end of the brushless DC motor (2) and the fitting part of the top structure of the outer protective shell (23). The bottom of the brushless DC motor (2) housing is connected to a first temperature sensor (21), and an auxiliary sleeve (22) installed on the top housing surface of the UAV body (1) is fixed on the bottom housing surface of the first temperature sensor (21).

3. The UAV-specific motor according to claim 1, characterized in that: The cooling oil pump assembly includes a cooling oil box (4), a water pump (5), an annular pipe (6), and an auxiliary support (7). The surface of the cooling oil box (4) is provided with a relief groove, and a fixing seat is installed between the inner wall of the relief groove and the housing surface of the water pump (5). The output end and the input end of the water pump (5) are respectively fitted inside the annular pipe (6) and the bottom inner side of the cooling oil box (4). One end of the return solenoid valve pipe (10) is connected to the cooling oil box (4), and one end of the output solenoid valve pipe (11) is connected to the annular pipe (6).

4. A drone-specific motor according to claim 3, characterized in that: The auxiliary support (7) includes a threaded rod. One end of the threaded rod is fixed to the inner wall of the bottom of the UAV body (1), and the other end of the threaded rod is engaged with a linkage sleeve plate fixed to the surface of the cooling oil box (4). The surface of the other end of the threaded rod is threaded with two limit nuts, and the two limit nuts can clamp and limit the linkage sleeve plate during the spiral locking process with the threaded rod.

5. A special motor for unmanned aerial vehicles according to claim 1, characterized in that: The flow guiding assembly includes an auxiliary cylinder (16). The top two sides of the auxiliary cylinder (16) are respectively fitted to the bottom ends of the second branch pipe (15) and the bottom ends of the first branch pipe (14). The top surface of the auxiliary cylinder (16) is fixedly connected to the outer surface of the bottom of the UAV body (1). The bottom structure of the auxiliary cylinder (16) has an air inlet hole, and the air inlet hole is covered with a sealing plate. An electromagnet (20) is fixedly sleeved on the inner side of the middle part of the auxiliary cylinder (16). The electromagnet (20) can open and adjust the sealing plate by magnetic repulsion, so that cold air in the environment can enter the interior of the auxiliary cylinder (16).

6. A drone-specific motor according to claim 5, characterized in that: The sealing plate includes an iron cover plate (17), a guide rod (18), and a spring (19). One end of the guide rod (18) is fixed to the top surface of the iron cover plate (17), and the other end of the guide rod (18) is fitted inside the auxiliary cylinder (16). The spring (19) is fitted to the outside of the other end of the guide rod (18), and the two ends of the spring (19) are respectively fixed to the inner wall of the bottom of the auxiliary cylinder (16) and the surface of the other end of the guide rod (18). When the spring (19) is not compressed, it elastically pulls the iron cover plate (17) to cover and seal the air inlet.

7. A special motor for unmanned aerial vehicles according to claim 1, characterized in that: The brushless DC motor (2) has a second temperature sensor (25) fixed on its housing surface. One end of the second temperature sensor (25) penetrates the outer protective shell (23) and extends to the outside of the outer protective shell (23). The other end of the second temperature sensor (25) is attached to the surface of the liquid cooling ring tube (8). The fitting part between the second temperature sensor (25) and the outer protective shell (23) is filled with strong epoxy glue for sealing.

8. A special motor for unmanned aerial vehicles according to claim 1, characterized in that: A self-cleaning component (24) is provided between one end of the return solenoid valve tube (10) and the cooling oil box (4). The self-cleaning component (24) includes a semi-open cylinder (241), a sealing rod (242), and a transition cylinder (243). One end of the semi-open cylinder (241) is fixedly sleeved with the shell at the bottom of the UAV body (1) and extends to the outside of the bottom of the UAV body (1). One end of the sealing rod (242) and the transition cylinder (243) are both snapped into the inside of the semi-open cylinder (241). An annular filter plate (245) is nested and fixed between the surface of one end of the sealing rod (242) and the bottom inner side of the transition cylinder (243). The inner wall at the bottom of the semi-open cylinder (241) is provided with an internal thread. The surface at the other end of the sealing rod (242) is provided with an external thread. The other end of the sealing rod (242) can be detachably connected to the semi-open cylinder (241) through the helical engagement of the external thread and the internal thread. The other end of the sealing rod (242) is fitted with a leak-proof sealing ring (247) that can fill and seal the gap between the sealing rod (242) and the inner wall of the semi-open cylinder (241), and a transition pipe (246) is installed between the bottom of one end of the semi-open cylinder (241) and the cooling oil box (4).

9. A special motor for unmanned aerial vehicles according to claim 8, characterized in that: A second temperature sensor (25) is fixedly sleeved inside the other end of the semi-open cylinder (241), and an assembly groove is opened inside the other end of the sealing rod (242), and a torsion rod (244) is fixedly sleeved inside the assembly groove.

10. A control system for a drone-specific motor as described in claim 1, characterized in that, The control system includes a flight control computing processor, a signal output unit, an electronic speed controller processing unit, a motor drive unit, a battery module, and a motor temperature monitoring unit composed of a first temperature sensor (21) and a second temperature sensor (25). The control system is electrically connected to several brushless DC motors (2) via wires.

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