Towing apparatus

Abstract

A towing apparatus, comprising a winch module (10), a pulley module and a power supply (41), wherein the winch module (10) comprises a winch (11) and a driving assembly in transmission connection with the winch (11), with a twisted rope (12) winding around the winch (11); the pulley module comprises at least one movable pulley (31), with the twisted rope (12) winding around the movable pulley (31), and the movable pulley (31) being used to be connected to a device to be towed; and the power supply (41) is electrically connected to the driving assembly.

Description

Towing device

[0001] This application claims priority to the Chinese patent application filed with the China Patent Office on March 7, 2024, with application number 202420445201.1 and application name “Towing Device,” the entire contents of which are incorporated herein by reference. Technical Field

[0002] The present application relates to the technical field of traction devices, and in particular to a towing device. Background Art

[0003] Winches are essential self-protection and towing devices for vehicles and vessels. They can be used for rescue or self-rescue in harsh environments such as deserts, snow, beaches, swamps, and muddy roads, as well as for operations such as obstacle removal and towing objects. However, to accommodate large towed equipment, large-diameter or multi-drum winches are typically used, which increases the overall size and weight, making them unsuitable for use in extreme environments. Summary of the Invention

[0004] The main purpose of this application is to provide a towing device, aiming to improve the miniaturization level of the towing device.

[0005] To achieve the above objectives, the towing device proposed in this application includes:

[0006] A winch module includes a winch and a drive assembly connected in a transmission manner, wherein a winch rope is wound around the winch;

[0007] a pulley module, comprising at least one movable pulley, the rope being wound around the movable pulley, the movable pulley being used to connect to the equipment to be towed; and

[0008] A power supply electrically connected to the drive assembly;

[0009] The movable pulley is connected to n rope segments for bearing the weight of the equipment to be towed, and satisfies μG1=nF1, n≥2, wherein F1 is the tension applied by the winch on the winch, G1 is the total weight of the equipment to be towed, and μ is the friction coefficient between the equipment to be towed and the equipment placement surface.

[0010] Optionally, the pulley module further includes at least one fixed pulley, the fixed pulley is fixedly arranged relative to the winch, and the fixed pulley is connected to the movable pulley via the rope.

[0011] Optionally, the total pulling force of the towing device is F2, F2=μG1=nF1, 0.9t≤F2≤15t.

[0012] Optionally, the value of n is 2, 3, 5, 7, 9 or 11.

[0013] Optionally, the total weight of the winch module, the pulley module and the power supply is G2, 5kg≤G2≤8kg.

[0014] Optionally, the winch module further includes a rope guide for guiding the winding of the winch rope on the winch.

[0015] Optionally, the driving assembly includes a motor and a labor-saving mechanism in a transmission connection, the labor-saving mechanism is connected to the winch, and the motor is connected to the power supply.

[0016] Optionally, the labor-saving mechanism is configured as a first gear and a second gear that are meshed with each other, the first gear is coaxially driven with the winch, the second gear is connected to the motor, and the size of the first gear is larger than that of the second gear.

[0017] Optionally, an external power supply is also included, and the external power supply is used to charge the power supply.

[0018] Optionally, the weight of the external power supply is G3, 3kg≤G3≤4kg.

[0019] Optionally, the power supply is configured as a lithium battery, and / or the external power supply is configured as a solid-state battery.

[0020] Optionally, the power power supply and / or the external power supply is connected to the vehicle power supply via a vehicle inverter.

[0021] Optionally, the power supply and / or the external power supply is connected to the mains via a global voltage charger.

[0022] Optionally, a first thermal insulation layer is provided outside the power supply.

[0023] Optionally, the first thermal insulation layer includes a stacked aerogel layer and an XPS extruded board.

[0024] Optionally, the power power supply is provided with a first heating device externally, and the first heating device is electrically connected to the external power supply.

[0025] Optionally, a second thermal insulation layer is provided outside the external power supply.

[0026] Optionally, the second thermal insulation layer includes a stacked aerogel layer and an XPS extruded board.

[0027] Optionally, the external power supply is provided with a second heating device, and the second heating device is electrically connected to the external power supply.

[0028] Optionally, the power power supply is provided with a first heating device, and the external power supply is provided with a second heating device. When the external power supply supplies power to the first heating device and the second heating device at the same time, the power supply time of the external power supply is T, 500h≤T≤800h.

[0029] In the technical solution of the present application, the towing device includes a winch module, a pulley module and a power supply, wherein the winch and the movable pulley are connected by a rope, and the winch transmission is connected to a driving component. Under the drive of the driving component, the winch rotates and provides a pulling force to the rope. Since the rope is wound around the movable pulley, the movable pulley moves linearly close to the winch under the action of the rope, thereby realizing the towing of the towed equipment. At the same time, the tension applied by the winch to the rope produces an effect of doubling the tension, which can not only improve the miniaturization level of the towing device, but also ensure that the towing device can reliably pull the towed equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] FIG1 is a schematic structural diagram of an embodiment of a towing device of the present application;

[0031] FIG2 is a schematic structural diagram of another embodiment of the pulley module in FIG1 ;

[0032] Figure 3 is a schematic structural diagram of the labor-saving mechanism;

[0033] FIG4 is a schematic diagram showing the structure of the connection between the power supply and / or external power supply and the vehicle power supply;

[0034] FIG5 is a schematic diagram showing the structure of the connection between the power supply and / or external power supply and the mains electricity.

[0035] Explanation of the accompanying drawings: 10. Winch module; 41. Power supply; 11. Winch; 411. First insulation layer; 12. Winch rope; 42. External power supply; 21. Motor; 421. Second insulation layer; 22. First gear; 43. Global voltage charger; 23. Second gear; 44. On-board inverter; 31. Movable pulley; 45. On-board power supply; 32. Fixed pulley; 50. Equipment to be towed. DETAILED DESCRIPTION

[0036] The technical solution of the present application is further elaborated in detail below in conjunction with the drawings and specific embodiments of the specification. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used herein in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application. In the following description, reference is made to "some embodiments", which describes a subset of all possible embodiments, but it should be understood that "some embodiments" may be the same subset or different subsets of all possible embodiments, and may be combined with each other without conflict.

[0037] It should also be noted that when an element is referred to as being "fixed to" another element, it may be directly on the other element or there may be an intermediate element. When an element is referred to as being "connected to" another element, it may be directly connected to the other element or there may be an intermediate element. The terms "vertical," "horizontal," "inner," "outer," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only implementation methods.

[0038] This application proposes a towing device. Referring to Figures 1 to 5, in an embodiment of the application, the towing device includes a winch module 10, a pulley module, and a power supply 41. The winch module 10 includes a drive-connected winch 11 and a drive assembly, with a winch rope 12 wound around the winch 11. The pulley module includes at least one movable pulley 31, with the rope 12 wound around the movable pulley 31, and the movable pulley 31 is used to connect to the towed equipment 50. The power supply 41 is electrically connected to the drive assembly. This configuration reduces the pulling force of the winch module 10 by using a movable pulley, avoids the use of large-diameter winches or multi-drum winches to complete the pulling, does not increase the overall volume and weight of the towing device, and helps to improve the miniaturization level of the towing device.

[0039] The winch 11 is fixed to the mounting surface of the winch 11 by, for example, a winch frame, a fixed rope, etc. The mounting surface of the winch 11 can be configured as an external shell of the winch 11, a vehicle, the ground or a tree, wherein one end of the rope 12 is fixed to the mounting surface of the winch 11, and the other end passes around the movable pulley 31 and is wound around the winch 11. Due to the separate arrangement of the movable pulley 31 and the winch 11, when the power supply 41 supplies power to the driving component, the driving component drives the winch 11 to rotate, so that the rope 12 is wound around the winch 11, and drives the movable pulley 31 to move linearly relative to the winch 11, thereby achieving towing of the towed equipment 50. Due to the cooperation between the movable pulley 31 and the rope 12, under the same pulling demand and towing distance, the tension applied by the winch 11 to the rope 12 produces an effect of doubling the tension, which helps to meet the improvement of the miniaturization level of the towing device, facilitates transportation and application, and can also ensure that the towing device can reliably pull the towed equipment 50. The number of movable pulleys 31 depends primarily on the weight of the towed equipment 50 and environmental factors at the location, including but not limited to space availability and the friction to be overcome. The winch 11 and drive assembly are integrated into a single unit, facilitating assembly and transmission coordination, while also miniaturizing the winch module 10.

[0040] In the technical solution of the present application, the towing device includes a winch module 10, a pulley module and a power supply 41, wherein the winch 11 and the movable pulley 31 are connected by a rope 12, and the winch 11 is connected to a driving component. Driven by the driving component, the winch 11 rotates and provides a pulling force to the rope 12. Because the rope 12 is wound around the movable pulley 31, the movable pulley 31 moves linearly close to the winch 11 under the action of the rope 12, thereby achieving the towing of the towed equipment 50. At the same time, the tension applied by the winch 11 to the rope 12 produces an effect of doubling the tension, which can not only improve the miniaturization level of the towing device, but also ensure that the towing device can reliably pull the towed equipment 50.

[0041] Specifically, in one embodiment, the movable pulley 31 is connected with n rope segments of the winch 12 for bearing the weight of the equipment to be towed 50, and satisfies μG1=nF1, n≥2, wherein F1 is the tension applied by the winch 11 on the winch 12, G1 is the total weight of the equipment to be towed 50, and μ is the friction coefficient between the equipment to be towed 50 and the equipment placement surface; specifically, by utilizing the n rope segments acting on the movable pulley 31, the tension applied to the winch 12 can be reduced to 1 / n times the friction force that the equipment to be towed 50 needs to overcome, thereby helping to reduce the tension output, thereby reducing the output of the drive component and the power supply 41, and improving the miniaturization level of the towing device. It can be understood that the weight of the equipment to be towed 50 borne by the rope segment connected to the movable pulley 31 refers to the corresponding force generated by the rope segment pulling the equipment to be towed 50 to move, and thus the weight of the equipment to be towed 50 borne by the rope segment can be understood as referring to the pulling force applied by the rope segment to the equipment to be towed 50.

[0042] Furthermore, the total pulling force of the towing device is F2, 0.9t≤F2≤15t; that is, the total pulling force can overcome the friction force corresponding to the towed equipment 50, thereby ensuring the reliable towing of the towed equipment 50, wherein the specific value of the total pulling force F2 can be 1.8t, 2.7t, 3.6t, 4.5t, 5.4t, 6.3t, 7.2t, 8.1t, 9t, 9.9t, 10.8t, 12.7t, 13.6t, 14.5t, 15t, etc., and because F2=μG1=nF1, the total pulling force F2 is n times the pulling force F1, which is convenient for determining the number of movable pulleys 31, the winding length of the rope 12 and the moving distance of the towed equipment 50.

[0043] Optionally, in one embodiment, the pulley module further includes at least one fixed pulley 32, which is fixedly disposed relative to the capstan 11 and is used to change the direction of the rope 12. This, in conjunction with the arrangement of the movable pulley 31, can increase the effort saving to a certain extent. The fixed pulley 32 can be mounted on the capstan frame or the mounting surface of the capstan 11 to ensure relative stillness between the fixed pulley 32 and the capstan 11, thereby ensuring normal movement of the movable pulley 31 and reliable retraction of the rope 12 by the capstan 11. The number of fixed pulleys 32 depends primarily on the number of movable pulleys 31.

[0044] Furthermore, n is 2, 3, 5, 7, 9, or 11. When n is 2, as shown in FIG1 , one movable pulley 31 is provided, and two rope segments are provided on the movable pulley 31. Of course, in other embodiments, one movable pulley 31 is provided, one fixed pulley 32 is provided, and two rope segments are provided on the movable pulley 31, which can also achieve a 2-fold increase in pulling force. When n is 3, as shown in FIG2 , one movable pulley 31 is provided, two fixed pulleys 32 are provided, and three rope segments are provided on the movable pulley 31, which can achieve a 3-fold increase in pulling force. Similarly, when towing the same towed equipment 50, in order to further reduce the pulling force F1, multiple movable pulleys 31 are provided, and the total number of rope segments on each movable pulley 31 corresponds to the multiple by which the total pulling force is reduced.

[0045] Optionally, in one embodiment, the winch module 10 further includes a rope guide for guiding the winding of the rope 12 on the winch 11, so that the rope 12 can be regularly wound on the winch 11, reducing the risk of rope disorder (the rope is locally accumulated when winding on the winch 11, forming irregular accumulation) and rope biting (during the winding process, the latter rope is squeezed and rubbed with the previous rope or the next layer of rope, and even causes the rope loops to be intertwined), effectively protecting and extending the service life of the winch 11 and the rope 12. The rope guide can be installed on the winch 11 frame or the winch 11 mounting surface to ensure that the rope guide does not rotate when the winch 11 rotates, ensuring the functional operation of the rope guide.

[0046] Optionally, in one embodiment, the driving assembly includes a transmission-connected motor 21 and a labor-saving mechanism, the labor-saving mechanism is connected to the winch 11, and the motor 21 is connected to the power supply 41, thereby improving the power utilization rate of the power supply 41 and ensuring the normal operation of the winch 11.

[0047] 1 and 3 , in one embodiment, the labor-saving mechanism is configured as a first gear 22 and a second gear 23 that are meshed with each other. The first gear 22 is coaxially driven with the winch 11, and the second gear 23 is connected to the motor 21. The size of the first gear 22 is larger than the size of the second gear 23. Then, under the driving action of the motor 21, the second gear 23 drives the first gear 22 to rotate, and the first gear 22 drives the winch 11 to rotate, thereby realizing the winding of the rope 12. The meshing transmission of the first gear 22 and the second gear 23 helps to improve the accuracy of the transmission. Also, because the size of the second gear 23 is smaller than that of the first gear 22, a larger torque can be provided to the winch 11 through the first gear 22, which saves labor and satisfies the pulling of the rope 12 on the towed equipment 50.

[0048] The first gear 22 can be connected to the end surface of the winch 11. As shown in FIG1 , the first gear 22 is disposed on the side of the winch 11 facing away from the rope 12. The connection between the first gear 22 and the winch 11 includes, but is not limited to, welding, bonding, or integral molding. The first gear 22 can also be configured as a toothed structure formed around the winch 11, which helps to achieve miniaturization of the winch module 10. In other embodiments, the labor-saving mechanism can be configured as a crank mechanism.

[0049] In order to avoid insufficient power of the power supply 41, in one embodiment, the towing device also includes an external power supply 42, which is used to charge the power supply 41. By adding an external power supply 42, the external power supply 42 can charge the power supply 41, ensuring the continuity of the power supply 41 to the motor 21 and improving the reliability of the towing device.

[0050] Optionally, in one embodiment, the power source 41 is configured as a lithium battery, which may be a liquid lithium battery, so as to provide a higher charging and discharging power, ensure the normal use of the motor 21, and the cost of the lithium battery is low, which helps to save costs; of course, in other embodiments, the lithium battery may be a solid-state battery.

[0051] Optionally, in one embodiment, the external power supply 42 is configured as a solid-state battery. Due to the inherent characteristics of the solid-state battery, the solid-state battery has higher safety in use and can operate in a larger temperature range. Therefore, in a low-temperature environment, the solid-state battery has good low-temperature performance and capacity, thereby facilitating powering the power supply 41 in a low-temperature environment.

[0052] In addition, compared with liquid batteries, solid-state batteries have a smaller assembly volume and are easier to carry.

[0053] In order to prevent the power supply 41 from being unable to work due to being in a low temperature environment such as -40°C, the power supply 41 is provided with a first insulation layer 411 and / or a first heating device, and the first heating device is electrically connected to the external power supply 42; specifically, in one embodiment, the power supply 41 is provided with a first insulation layer 411, and the first insulation layer 411 wraps the power supply 41, which can effectively reduce the heat loss of the power supply 41 and reduce the impact of the low temperature environment on the power supply 41. However, in other embodiments, the first insulation layer 411 can be provided inside the power supply 41. ; In another embodiment, a first heating device is provided outside the power power supply 41, and the first heating device is connected to the external power supply 42, and then power is supplied to the first heating device through the external power supply 42. The heat generated by the first heating device acts on the power power supply 41, reducing the impact of the low temperature environment on the power power supply 41, and ensuring the normal use of the power power supply 41; in another embodiment, a first thermal insulation layer 411 and a first heating device are provided outside the power power supply 41 at the same time. The first thermal insulation layer 411 can be used to lock the heat generated by the first heating device, further reducing the impact of the low temperature environment on the power power supply 41.

[0054] Specifically, the first thermal insulation layer 411 includes a stacked aerogel layer and an XPS extruded board, wherein the aerogel layer and the XPS extruded board are connected by bonding or the like, and are connected to the power supply 41 through the aerogel layer or the XPS extruded board, and the whole covers the outside of the power supply 41, or the aerogel layer and the XPS extruded board are separately arranged inside and outside the power supply 41; however, in other embodiments, the first thermal insulation layer 411 only includes an aerogel layer or an XPS extruded board, or the second thermal insulation layer 421 includes a thermal insulation board made of other thermal insulation materials.

[0055] In order to prevent the external power supply 42 from being unable to work due to being in a low temperature environment, the external power supply 42 is provided with a second insulation layer 421 and / or a second heating device, and the second heating device is electrically connected to the external power supply 42; specifically, in one embodiment, the external power supply 42 is provided with a second insulation layer 421, and the second insulation layer 421 wraps the external power supply 42, which can effectively reduce the heat loss of the external power supply 42 and reduce the impact of the low temperature environment on the external power supply 42; however, in other embodiments, the second insulation layer 421 can be provided inside the external power supply 42; in another embodiment, the second insulation layer 421 can be provided inside the external power supply 42; In an embodiment, a second heating device is provided outside the external power supply 42, and the second heating device is connected to the external power supply 42, and then power is supplied to the second heating device through the external power supply 42. The heat generated by the second heating device acts on the external power supply 42, reducing the impact of the low temperature environment on the external power supply 42 and ensuring the normal use of the external power supply 42; in another embodiment, a second thermal insulation layer 421 and a second heating device are provided outside the external power supply 42 at the same time, and the second thermal insulation layer 421 can be used to lock the heat generated by the second heating device, further reducing the impact of the low temperature environment on the external power supply 42.

[0056] Specifically, the second thermal insulation layer 421 includes a stacked aerogel layer and an XPS extruded board; wherein the aerogel layer and the XPS extruded board are connected by bonding or the like, and are connected to the external power supply 42 through the aerogel layer or the XPS extruded board, and the entire layer covers the outside of the external power supply 42, or the aerogel layer and the XPS extruded board are separately arranged inside and outside the external power supply 42; however, in other embodiments, the second thermal insulation layer 421 only includes the aerogel layer or the XPS extruded board, or the second thermal insulation layer 421 includes an insulation board made of other thermal insulation materials.

[0057] In addition, in order to ensure the reliable operation of the towing device, the first heating device and the second heating device can be set to stop working when the temperature is higher than the first temperature value and start working when the temperature is lower than the second temperature value. Specifically, the first temperature value can be 15°C and the second temperature value can be 10°C.

[0058] Optionally, in one embodiment, when the external power supply 42 supplies power to the first heating device and the second heating device at the same time, the power supply time of the external power supply 42 is T, 500h≤T≤800h. Since the external power supply 42 is configured as a solid-state battery, specifically a ternary polymer lithium battery, which has large capacity and high safety, the external power supply 42 can supply power to the first heating device and the second heating device at the same time, and the power supply time can be as long as 500h to 800h, which can not only ensure the power supply of the power supply 41 to the motor 21, but also reduce the impact of the low temperature environment on the power supply 41 and the external power supply 42, which helps to improve the reliability of the towing device and the wide range of application environments.

[0059] Optionally, in one embodiment, the total weight of the winch module 10, the pulley module and the power supply 41 is G2, 5kg≤G2≤8kg; and / or the weight of the external power supply 42 is G3, 3kg≤G3≤4kg; this facilitates the transportation and application of the towing device, and improves the miniaturization level of the towing device while ensuring the reliable application of the towing device.

[0060] Referring to Figure 4, in one embodiment, the power power supply 41 and / or the external power supply 42 are connected to the vehicle power supply 45 through the vehicle inverter 44, and then the existing vehicle power supply 45 is used to power the power power supply 41 and / or the external power supply 42, and the vehicle inverter 44 is used to ensure that the DC power of the vehicle power supply 45 can be converted into AC power for use by the external power supply 42, which is convenient, fast, and safe.

[0061] To adapt to different power supply standards in different countries, the power supply voltage in different countries generally ranges from 100V to 240V. Therefore, as shown in Figure 5, in one embodiment, the power supply 41 and / or the external power supply 42 are connected to the mains via a global voltage charger 43 that is compatible with global voltages. This adapts to the power supply standards of different countries and thus meets the charging needs of the power supply 41 and / or the external power supply 42. Specifically, the global voltage charger 43 can be connected to a charging station or a regular socket.

[0062] The above are only specific embodiments of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in this application should be included in the scope of protection of the present application. The scope of protection of the present application should be based on the scope of protection of the claims.

Claims

1. A towing device, characterized in that: include: A winch module (10) comprises a winch (11) and a drive assembly connected to the winch (11), wherein a winch rope (12) is wound around the winch (11); A pulley module comprises at least one movable pulley (31), the rope (12) being wound around the movable pulley (31), and the movable pulley (31) being used to connect to the equipment to be towed (50); and a power source (41) electrically connected to the drive assembly; The movable pulley (31) is connected to n rope segments for bearing the weight of the device to be towed (50), and μG1=nF1, n≥2 is satisfied, wherein F1 is the tension applied by the winch (11) on the winch (12), G1 is the total weight of the device to be towed (50), and μ is the friction coefficient between the device to be towed (50) and the device placement surface.

2. The towing device according to claim 1, wherein: The pulley module further comprises at least one fixed pulley (32), the fixed pulley (32) and the winch (11) being fixedly arranged relative to each other, and the fixed pulley (32) and the movable pulley (31) being connected via the rope (12).

3. The towing device according to claim 1, wherein: The total pulling force of the towing device is F2, F2=μG1=nF1, 0.9t≤F2≤15t.

4. The towing device according to claim 1, wherein: The value of n is 2, 3, 5, 7, 9 or 11.

5. The towing device according to claim 1, wherein: The total weight of the winch module (10), the pulley module and the power supply (41) is G2, 5kg≤G2≤8kg.

6. The towing device according to claim 1, wherein: The winch module (10) further comprises a rope guide for guiding the winding of the winch rope (12) on the winch (11).

7. The towing device according to claim 1, wherein: The driving assembly comprises a transmission-connected motor (21) and a labor-saving mechanism, the labor-saving mechanism is connected to the winch (11), and the motor (21) is connected to the power source (41).

8. The towing device according to claim 7, characterized in that The labor-saving mechanism is configured as a first gear (22) and a second gear (23) that are meshed with each other, the first gear (22) is coaxially driven with the winch (11), the second gear (23) is connected to the motor (21), and the size of the first gear (22) is larger than that of the second gear (23).

9. The towing device according to claim 1, wherein: It also includes an external power supply (42), and the external power supply (42) is used to charge the power supply (41).

10. The towing device according to claim 9, characterized in that The weight of the external power supply (42) is G3, 3kg≤G3≤4kg.

11. The towing device according to claim 9, characterized in that The power source (41) is configured as a lithium battery, and / or the external power source (42) is configured as a solid-state battery.

12. The towing device according to claim 9, wherein: The power source (41) and / or the external power source (42) are connected to the vehicle power source (45) via a vehicle inverter (44).

13. The towing device according to claim 9, wherein: The power supply (41) and / or the external power supply (42) are connected to the mains electricity via a global voltage charger (43).

14. The towing device according to claim 1 or 9, characterized in that: A first heat-insulating layer (411) is provided outside the power source (41).

15. The towing device according to claim 14, characterized in that The first thermal insulation layer (411) comprises a stacked aerogel layer and an XPS extruded board.

16. The towing device according to claim 1 or 9, characterized in that: The power source (41) is provided with a first heating device externally, and the first heating device is electrically connected to the external power source (42).

17. The towing device according to claim 9, wherein: The external power supply (42) is provided with a second heat-insulating layer (421) outside.

18. The towing device according to claim 17, characterized in that The second thermal insulation layer (421) comprises a stacked aerogel layer and an XPS extruded board.

19. The towing device according to claim 9, wherein: The external power supply (42) is provided with a second heating device, and the second heating device is electrically connected to the external power supply (42).

20. The towing device according to claim 9, wherein: The power supply (41) is externally provided with a first heating device, and the external power supply (42) is externally provided with a second heating device. When the external power supply (42) supplies power to the first heating device and the second heating device simultaneously, the power supply duration of the external power supply (42) is T, and 500h≤T≤800h.

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