Liquid-cooled hub motor and electric vehicle using same

Abstract

A liquid cooling wheel hub motor and an electric vehicle using the same, the liquid cooling wheel hub motor comprises a support shaft, a stator arranged on the support shaft and a wheel hub, a cavity is formed in the wheel hub, the stator is located in the cavity, and cooling liquid is arranged in the cavity; a stator inner cavity communicated with the cavity is formed in the stator support, and air holes communicated with the stator inner cavity are formed in the stator support; the ventilation channel is communicated with the interior of the cavity and the exterior of the cavity and comprises a ventilation pipe; one end of the vent pipe communicates with the vent hole through the breathing positioning piece, and the other end of the vent pipe communicates with the outside of the cavity. Compared with the prior art, the liquid-cooled hub motor provided by the utility model has the following advantages: the vent pipe is communicated with the vent hole in the stator bracket through the breathing positioning piece, so that the problem that oil flows along the inner wall of the stator inner cavity when the vent pipe is directly inserted into the stator inner cavity and the outer wall of the vent pipe is attached to the inner wall of the stator inner cavity is avoided; and the risk of entering a vent pipe opening is avoided.

Description

Technical Field

[0001] The utility model relates to a hub motor, in particular to a liquid-cooled hub motor and an electric vehicle using the motor. Background Art

[0002] With the increasing popularity of electric bicycles and electric motorcycles in the market, the requirements for the performance and functions of electric vehicles are also increasing. As the core component of an electric vehicle, the heat dissipation of the drive hub motor system is a major problem. At present, the common heat dissipation method of electric vehicle hub motors on the market is mostly air cooling, and the heat dissipation effect is not good. When an electric vehicle rides overload, the temperature inside the motor rises rapidly. After the temperature rises to a certain level, it is sufficient to cause the demagnetization of the motor magnetic steel and the decline of the insulation ability, resulting in the reduction of the reliability of the electric vehicle motor. The heat of the motor is mainly generated by the stator. Most of the existing heat dissipation of the hub motor stator is to conduct the heat from the stator to the air inside the hub, and the air conducts the heat to the outside of the motor through the rotor, that is, the hub shell. The heat dissipation efficiency is low, and the over-high temperature rise inside the hub motor causes potential hazards such as the demagnetization of the permanent magnet and the accelerated aging of the coil insulation layer; even burns out the motor coil, resulting in motor damage and affecting driving safety.

[0003] Subsequently, liquid-cooled hub motors emerged, that is, a certain amount of coolant is injected into the hub motor. The heat on the stator can be quickly conducted to the hub end cover through the coolant and dissipated to the outside through the end cover, greatly improving the heat dissipation efficiency of the hub motor.

[0004] Since the hub motor is a sealed structure, the air pressure will increase when it generates heat inside. Therefore, a waterproof breathable valve is generally set on the end cover of the hub motor to balance the air pressure inside and outside the hub motor and prevent the sealing failure caused by the inability to relieve the pressure in time due to the too high internal air pressure, so that water enters the motor internal, causing damage. The characteristic of the waterproof breathable valve is that it serves as a breathable channel inside and outside the hub motor under normal circumstances. When the waterproof breathable valve comes into contact with water, the waterproof breathable membrane on it will immediately close to prevent water from entering the hub motor internal. When the water on the waterproof breathable membrane dries, its breathable function can be restored.

[0005] When injecting coolant into the liquid-cooled hub motor, cooling oil is generally used. When the cooling oil contacts the waterproof breathable membrane from the inside, it will cause irreversible damage to the waterproof breathable membrane, making it lose the functions of waterproof and breathable. As a result, the air pressure inside the hub motor cannot be balanced with the outside world, and the pressure inside the hub motor will leak from the seal, resulting in oil leakage, damaging the seal of the hub motor, reducing the service life of the motor, and causing potential safety hazards when the leaked coolant contacts the brake part. Losing the waterproof function and water entering the motor internal will also inevitably cause damage to the motor.

[0006] The invention patent with the authorization announcement date of January 22, 2021, named "Oil-cooled Motor" and the application publication number of CN108880109B connects the inside and outside of the motor through a ventilation pipe. A gas-liquid separation device is provided at the pipe head inside the motor, so that the cooling oil and air passing through the gas-liquid separation device are discharged through different paths, thereby preventing the cooling oil from entering the ventilation pipe. A waterproof breathable membrane is provided at the other end of the ventilation pipe, and the ventilation pipe extends out of the motor through the channel of the control wire harness on the rotating shaft. The gas-liquid separation device in this invention is a three-way component. The oil inlet is located at the upper end, the oil drain port is located at the lower end, and the air inlet and exhaust port are located at the side end. To a certain extent, it can relieve the cooling oil from entering the ventilation pipe. However, when the motor rotates at high speed, a large amount of cooling oil will splash onto the part of the oil inlet. With the bumping of the vehicle, some oil will enter the ventilation pipe. Although a desiccant is provided at the front end of the waterproof breathable membrane, it can only slow down the speed of the cooling oil contacting the waterproof breathable membrane. Once the waterproof breathable membrane contacts the cooling oil, the waterproof and breathable functions will fail.

[0007] Another example is the utility model application named "A Liquid-cooled Hub Motor and an Electric Vehicle Using the Same for Preventing Oil by Using a Stator Bracket" applied by the applicant on July 21, 2024, with the application number of 2024217342039. An embodiment of this application discloses inserting a ventilation pipe into the inner cavity of the stator bracket to communicate with the inner cavity of the stator bracket. However, after the ventilation pipe is inserted into the inner cavity of the stator bracket in this scheme, it generally at least abuts against the inner wall on one side of the stator inner cavity. Although there will be no oil splash in the stator inner cavity, there may still be a phenomenon that the oil flows along the stator inner cavity. The pipe orifice direction of the ventilation pipe is parallel to the oil flow direction and is close to the side wall of the stator inner cavity. In this way, the oil is very likely to enter the ventilation pipe from the side wall of the stator inner cavity. When the amount of the entered oil reaches a certain level, it will inevitably soak through the waterproof breathable valve on the other side of the ventilation channel, causing damage to the waterproof breathable valve and losing the breathable function, and ultimately resulting in the air pressure imbalance inside and outside the motor chamber, and water ingress or oil leakage. Utility Model Content

[0008] The purpose of the present utility model is to overcome the deficiencies of the prior art and provide a liquid-cooled hub motor and an electric vehicle using the motor.

[0009] The main technical solution adopted by the liquid-cooled hub motor provided by the present utility model is as follows: It includes a support shaft, a stator provided on the support shaft, and a hub. The hub includes two end covers arranged oppositely, a chamber is formed inside the hub, the stator is located inside the chamber, and a coolant is also provided inside the chamber. The stator includes a stator bracket fixed on the support shaft and a stator core provided on the outer periphery of the stator bracket. A stator inner cavity communicating with the chamber is provided inside the stator bracket, and a ventilation hole communicating with the stator inner cavity is provided on the stator bracket. It also includes a ventilation passage communicating the inside of the chamber with the outside of the chamber. The ventilation passage includes a ventilation pipe. One end of the ventilation pipe is communicated with the ventilation hole through a breathing positioning member, and the other end of the ventilation pipe is communicated with the outside of the chamber.

[0010] The liquid-cooled hub motor provided by the present utility model also adopts the following auxiliary technical solutions:

[0011] Preferably, the breathing positioning member is connected to the stator bracket. The breathing positioning member is provided with a first breathing port and a second breathing port that are connected and communicated. An oil-proof protrusion is provided on the first breathing port. When the first breathing port is communicated with the ventilation hole, the oil-proof protrusion is inserted into the ventilation hole, and the oil-proof protrusion protrudes from the inner wall around the ventilation hole. The second breathing port is communicated with the ventilation pipe.

[0012] Preferably, a clamping joint is provided on the first breathing port. The clamping joint is inserted into the ventilation hole and clamped on the ventilation hole. The front end of the clamping joint enters the stator inner cavity and forms an oil-proof protrusion.

[0013] Preferably, a waterproof and breathable device is provided inside the breathing positioning member, and the waterproof and breathable device is located between the first breathing port and the second breathing port.

[0014] Preferably, the breathing positioning member includes a body. A breathing cavity is provided inside the body. The first breathing port and the second breathing port are both communicated with the breathing cavity. The first breathing port is located on the side wall of the body, and the second breathing port is located on the bottom wall of the body.

[0015] Preferably, a shaft channel is provided on the support shaft, and the ventilation pipe extends out of the chamber through the shaft channel.

[0016] Preferably, a waterproof and breathable device is provided at the end of the ventilation pipe located outside the chamber.

[0017] Preferably, the ventilation passage further includes a shaft channel provided on the support shaft. One end of the shaft channel is connected to the ventilation pipe inside the chamber, and the other end is communicated with the outside of the chamber.

[0018] Preferably, a waterproof and breathable device is provided at the other end of the shaft channel.

[0019] Preferably, the ventilation passage further includes an annular air guide cavity provided on the end cover around the support shaft. The other end of the shaft channel is communicated with the annular air guide cavity, and a waterproof and breathable device is provided on the annular air guide cavity.

[0020] Preferably, a bushing is provided on the support shaft, a bushing channel is provided on the bushing, and the breather tube extends out of the chamber through the bushing channel.

[0021] Preferably, a waterproof and breathable device is provided at one end of the breather tube outside the chamber.

[0022] Preferably, a bushing is provided on the support shaft, and the ventilation channel further includes a bushing channel provided on the bushing. One end of the bushing channel is connected to the breather tube inside the chamber, and the other end is communicated with the outside of the chamber.

[0023] Preferably, a waterproof and breathable device is provided at the other end of the bushing channel.

[0024] The main technical solution adopted by the electric vehicle provided by the present invention is as follows: It includes a frame, a hub motor provided on the frame, a tire provided on the hub motor, and a battery and a controller provided on the frame. The hub motor includes a support shaft, a stator provided on the support shaft, and a hub. The hub includes two end covers arranged oppositely, a chamber is formed inside the hub, the stator is located inside the chamber, and a coolant is also provided inside the chamber; the stator includes a stator bracket fixed on the support shaft and a stator core provided on the outer periphery of the stator bracket. A stator inner cavity communicated with the chamber is provided inside the stator bracket, and a ventilation hole communicated with the stator inner cavity is provided on the stator bracket; it also includes a ventilation channel communicating the inside of the chamber with the outside of the chamber, and the ventilation channel includes a breather tube; one end of the breather tube is communicated with the ventilation hole through a breathing positioning member, and the other end of the breather tube is communicated with the outside of the chamber.

[0025] Compared with the prior art, the liquid-cooled hub motor and the electric vehicle provided by the present invention have the following advantages: The ventilation process between the inside and the outside of the chamber still passes through the stator inner cavity. The breather tube is communicated with the ventilation hole on the stator bracket through the breathing positioning member, avoiding the risk that when the breather tube is directly inserted into the stator inner cavity, when the outer wall of the breather tube abuts against the inner wall of the stator inner cavity, and oil flows along the inner wall of the stator inner cavity and enters the breather tube port; moreover, when the breather tube is inserted into the stator inner cavity, it is difficult to control the insertion length. If the insertion length is too long and its pipe orifice abuts against the inner wall of the stator inner cavity, when the air pressure inside the chamber is greater than the external air pressure, there will be a risk of oil being sucked into the breather tube; and the setting of the breathing positioning member enables the breather tube not to be inserted into the stator inner cavity and is only communicated with the ventilation hole on the stator bracket. When oil flows along the inner wall of the stator inner cavity, there is no pipe orifice directly facing the oil flow direction, and it is difficult for the oil to enter the breather tube, thereby ensuring that the waterproof and breathable device provided in the ventilation channel or in the breathing positioning member is not contacted by the oil and fails, and ensuring the stability and reliability of the ventilation between the inside and the outside of the chamber 4. Description of the Drawings

[0026] Figure 1 It is a cross-sectional view of the liquid-cooled hub motor in the first embodiment of the present invention.

[0027] Figure 2For Figure 1 An enlarged view of A in

[0028] Figure 3 This is a structural diagram of the breathable positioning member in the present utility model.

[0029] Figure 4 This is a cross-sectional view of the liquid-cooled hub motor in the fifth embodiment of the present utility model.

[0030] Figure 5 This is a structural diagram of the liquid-cooled hub motor of the present utility model. Specific embodiments

[0031] In order to make the above objects, features, and advantages of the present utility model more obvious and understandable, the present utility model will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0032] Embodiment 1

[0033] Refer to Figures 1 to 3 and Figure 5, according to the embodiment of the liquid-cooled hub motor provided by the utility model, it includes a support shaft 1, a stator 2 provided on the support shaft 1, and a hub 3. The hub 3 includes two end covers 32 arranged oppositely. A chamber 4 is formed inside the hub 3. The stator 2 is located inside the chamber 4, and a coolant 5 is also provided inside the chamber 4; the stator 2 includes a stator bracket 21 fixed on the support shaft 1 and a stator core 22 provided on the outer periphery of the stator bracket 21. A stator inner cavity 23 communicating with the chamber 4 is provided inside the stator bracket 21. A vent hole 24 communicating with the stator inner cavity 23 is provided on the stator bracket 21. It also includes a vent passage communicating the inside of the chamber 4 with the outside of the chamber 4. The vent passage includes a vent pipe 6. One end of the vent pipe 6 is communicated with the vent hole 24 through a breathing positioning member 7, and the other end of the vent pipe 6 is communicated with the outside of the chamber; the stator inner cavity 23 is communicated with the chamber 4, and finally the air pressure balance between the inside and the outside of the chamber 4 is realized. The hub 3 generally includes a rim 31 and end covers 32 provided on both sides of the rim 31, and the three together form the hub 3; there is also a structure in which the rim 31 and one of the end covers 32 are integrally formed, which will not be elaborated in detail here. The stator bracket 21 includes a first bracket single piece and a second bracket single piece buckled together. A stator inner cavity 23 is formed between the first bracket single piece and the second bracket single piece. A vent hole 24 communicating the stator inner cavity 23 with the chamber 4 is provided on the stator bracket 21. This hole can be a positioning hole or other process hole during the processing of the stator 2. The part where the stator inner cavity 23 is communicated with the chamber 4 can be an opening at other parts of the stator 2, or a gap between the two bracket single pieces, not this vent hole 24. During specific use, an oil filling port (not shown in the figure) is provided on one of the two end covers 32 of the hub 3. The oil filling port is provided with a detachable bolt to facilitate oil filling or oil change inside the chamber 4. The volume of the coolant 5 is 5%-20% of the volume of the chamber 4. This embodiment is preferably 10%. The coolant 5 uses cooling oil, generally it can be: insulating cooling oil. Compared with the prior art, the air permeation process between the inside and the outside of the chamber 4 still passes through the stator inner cavity 23. The vent pipe 6 is communicated with the vent hole 24 on the stator bracket 21 through the breathing positioning member 7, avoiding the risk that when the vent pipe 6 is directly inserted into the stator inner cavity 23, when the outer wall of the vent pipe 6 abuts against the inner wall of the stator inner cavity 23, and the oil liquid flows along the inner wall of the stator inner cavity 23 and enters the vent of the vent pipe 6; and when the vent pipe 6 is inserted into the stator inner cavity 23, it is not easy to control the insertion length. When the insertion length is too long and its pipe orifice abuts against the inner wall of the stator inner cavity 23, when the air pressure inside the chamber 4 is greater than the external air pressure, there will be a risk of oil liquid being sucked into the vent pipe 6; and the setting of the breathing positioning member 7 enables the vent pipe 6 not to be inserted into the stator inner cavity 23, and only to be communicated with the vent hole 24 on the stator bracket 21. When the oil liquid flows along the inner wall of the stator inner cavity 23, there is no pipe orifice facing the flow direction of the oil liquid, and it is difficult for the oil liquid to enter the vent pipe 6, thus ensuring that the waterproof and breathable device 8 provided in the vent passage or in the breathing positioning member 7 is not contacted by the oil liquid and fails, and ensuring the stability and reliability of the air permeation between the inside and the outside of the chamber 4.

[0034] See Figures 1 to 3 , according to the above embodiments of the utility model, the breathing positioning member 7 is connected to the stator bracket 21. The breathing positioning member 7 is provided with a first breathing port 71 and a second breathing port 72 that are connected and communicated. The first breathing port 71 is provided with an oil-repellent protrusion 75. When the first breathing port 71 is communicated with the air-permeable hole 24, the oil-repellent protrusion 75 is inserted into the air-permeable hole 24, and the oil-repellent protrusion 75 protrudes from the inner wall around the air-permeable hole 24; the second breathing port 72 is communicated with the air-permeable pipe 6. The setting of the oil-repellent protrusion 75 enables the oil flowing down from the side wall of the stator inner cavity 23 to bypass around the oil-repellent protrusion 75 when passing through the first breathing port 71, avoiding the risk of oil flowing into the first breathing port 71 and improving the stability of the product.

[0035] See Figures 1 to 3 , according to the above embodiments of the utility model, the first breathing port 71 is provided with a clamping joint 74. The clamping joint 74 is inserted into the air-permeable hole 24 and clamped on the air-permeable hole 24. The front end of the clamping joint 74 enters the stator inner cavity 23 and forms an oil-repellent protrusion 75. During specific installation, a sealing ring is provided between the clamping joint 74 and the air-permeable hole 24. The setting of the clamping joint 74 not only realizes the connection and fixation between the breathing positioning member 7 and the stator bracket 21, but also the front end of its clamping joint 74 enters the stator inner cavity 23 and forms an oil-repellent protrusion 75, which not only simplifies the fixing structure of the breathing positioning member 7, but also achieves the purpose of preventing oil from entering the first breathing port 71, saving production costs, improving the assembly efficiency, and enhancing the reliability of the product.

[0036] See 1 and Figure 2 , according to the above embodiments of the utility model, a waterproof and breathable device 8 is provided inside the breathing positioning member 7. The waterproof and breathable device 8 is located between the first breathing port 71 and the second breathing port 72. The waterproof and breathable device 8 can be a waterproof and breathable valve or a waterproof and breathable membrane. In this embodiment, a waterproof and breathable membrane is provided in the breathing positioning member 7. By arranging the waterproof and breathable membrane in the breathing positioning member 7, the breathing positioning member 7 can also serve as a carrier for the waterproof and breathable membrane, eliminating the housing component of the waterproof and breathable device, and there is no need to provide the waterproof and breathable device 8 at other positions of the air-permeable channel, simplifying the assembly structure of the product and saving production costs. The waterproof and breathable membrane is the diaphragm in the waterproof and breathable valve in the prior art, that is, the diaphragm has a breathable function under normal circumstances and can be closed after contacting water to prevent water from entering the stator inner cavity 23 through the air-permeable pipe 6.

[0037] See Figure 2 and Figure 3, according to the above embodiments of the utility model, the breathing positioning member 7 includes a body. A breathing cavity 73 is provided inside the body. The first breathing port 71 and the second breathing port 72 are both communicated with the breathing cavity 73. The first breathing port 71 is located on the side wall of the body, and the second breathing port 72 is located on the bottom wall of the body. A pipe joint communicated with the breathing cavity 73 is provided on the body, and the second breathing port 72 is provided on the pipe joint. The body can be a hollow cylindrical structure. The pipe joint is provided on the bottom wall of the cylinder, and the oil-proof protrusion 75 is provided on the side wall of the cylinder. The breathing positioning member 7 has a simple structure, is convenient to process, and is easy to assemble.

[0038] See Figure 1 , according to the above embodiments of the utility model, a shaft channel 11 is provided on the support shaft 1, and the air-permeable pipe 6 extends out of the chamber 4 through the shaft channel 11. The shaft channel 11 can be a perforation for controlling the wire harness, or a shaft channel 11 separately opened on the support shaft. In this embodiment, the perforation for controlling the wire harness is adopted, and the air-permeable pipe 6 directly extends out of the chamber 4, simplifying the structure of the air-permeable channel, that is, the air-permeable channel is only the air-permeable pipe 6. One end of the air-permeable pipe 6 extending out of the chamber 4 can be fixed on the frame of the vehicle body or inserted into a certain part of the frame. When driving in low water level, water generally difficult to enter the air-permeable pipe 6. The structure is simple, the assembly is convenient, and the production cost is low.

[0039] Embodiment 2

[0040] This embodiment is substantially the same as the above Embodiment 1, except that the installation position of the waterproof and breathable device 8 is different. In this embodiment, the waterproof and breathable device 8 is not installed in the breathing positioning member 7; a waterproof and breathable device 8 is provided at one end of the air-permeable pipe 6 outside the chamber 4, and the waterproof and breathable device 8 is a waterproof and breathable membrane or a waterproof and breathable valve. In this embodiment, a waterproof and breathable valve is preferably adopted, and the waterproof and breathable valve is provided on the air-permeable pipe 6 outside the chamber 4, which is convenient for maintenance and replacement.

[0041] Embodiment 3

[0042] Compared with Embodiment 1, this embodiment is only different in the structure of the air-permeable channel. The air-permeable channel in this embodiment includes two parts, namely the air-permeable pipe 6 and the shaft channel 11 on the support shaft 1. That is, the air-permeable pipe 6 does not extend out of the chamber 4, but the air-permeable pipe 6 is hermetically connected to the shaft channel 11 on the support shaft 1 and communicates with the outside through the shaft channel 11 for ventilation. That is, the air-permeable channel further includes a shaft channel 11 provided on the support shaft 1. One end of the shaft channel 11 is connected to the air-permeable pipe 6 inside the chamber 4, and the other end communicates with the outside of the chamber 4. This structure eliminates the problem of fixing the air-permeable pipe 6 after it extends out of the chamber 4, and the assembly is convenient.

[0043] Embodiment 4

[0044] This embodiment is substantially the same as the above-described Embodiment 3, except for the installation position of the waterproof and breathable device 8. The other end of the shaft passage 11 is provided with the waterproof and breathable device 8, and the waterproof and breathable device 8 is a waterproof and breathable membrane or a waterproof and breathable valve. In this embodiment, a waterproof and breathable valve is used, and the waterproof and breathable valve is provided on the shaft passage 11 outside the chamber 4, which is convenient for maintenance and replacement.

[0045] Embodiment 5

[0046] See Figure 4 , this embodiment is substantially the same as the above-described Embodiment 3, except for the structure of the breathable passage. In this embodiment, the breathable passage further includes three parts, namely, the breathable pipe 6, the shaft passage 11 on the support shaft 1, and the annular air guide chamber 33 provided around the support shaft 1 on the end cover 32; one end of the shaft passage 11 is communicated with the breathable pipe 6, the other end of the shaft passage 11 is communicated with the annular air guide chamber, and the waterproof and breathable device 8 is provided on the annular air guide chamber. The waterproof and breathable device 8 in this embodiment uses a waterproof and breathable valve. Using the annular air guide chamber 33 on the end cover 32 as a part of the breathable passage, the waterproof and breathable valve can be provided on the end cover 32. The installation of the waterproof and breathable valve is more convenient, the structure is simple, no additional parts are required, and the production cost is saved; secondly, the other end of the shaft passage 11 is communicated with the annular air guide chamber 33, ensuring that when the annular air guide chamber 33 rotates with the end cover 32, the communication state can always be maintained. The structure is simple and ingenious, and the reliability is high.

[0047] Embodiment 6

[0048] This embodiment is substantially the same as the above-described Embodiment 1, except for the position where the breathable pipe 6 extends out of the chamber 4. An axle sleeve is added to the support shaft 1 in this embodiment; that is, an axle sleeve is provided on the support shaft 1, and an axle sleeve passage is provided on the axle sleeve. The breathable pipe 6 extends out of the chamber 4 through the axle sleeve passage. The setting of the axle sleeve can avoid opening holes on the support shaft 1, thereby avoiding the problem of reduced strength of the support shaft 1 caused by the holes. The breathable pipe 6 directly extends out of the chamber 4, simplifying the structure of the breathable passage, that is, the breathable passage is only the breathable pipe 6. One end of the breathable pipe 6 extending out of the chamber 4 can be fixed on the frame of the vehicle body or inserted into a certain part of the frame. When driving in low water level, water generally hardly enters the breathable pipe 6.

[0049] Embodiment 7

[0050] This embodiment is substantially the same as the above-described Embodiment 6, except for the installation position of the waterproof and breathable membrane. In this embodiment, the waterproof and breathable device 8 is not installed in the breathing positioning member 7; a waterproof and breathable device 8 is provided at one end of the breathable pipe 6 outside the chamber 4, and the waterproof and breathable device 8 is a waterproof and breathable membrane or a waterproof and breathable valve. This embodiment preferably uses a waterproof and breathable valve, and the waterproof and breathable valve is provided on the breathable pipe 6 outside the chamber 4, which is convenient for maintenance and replacement.

[0051] Embodiment VIII

[0052] This embodiment is substantially the same as Embodiment I above, except for the structure of the ventilation channel. The ventilation channel in this embodiment includes two parts, namely the ventilation pipe 6 and the sleeve channel on the sleeve. That is, the ventilation pipe 6 does not extend outside the chamber 4, but the ventilation pipe 6 is hermetically connected to the sleeve channel on the sleeve, and is ventilated to the outside through the sleeve channel. That is, a sleeve is provided on the support shaft 1, and the ventilation channel further includes a sleeve channel provided on the sleeve. One end of the sleeve channel is connected to the ventilation pipe 6 in the chamber 4, and the other end is communicated with the outside of the chamber 4. This structure eliminates the problem of the need to install and fix the ventilation pipe 6 after it extends outside, and is convenient for assembly.

[0053] Embodiment IX

[0054] This embodiment is substantially the same as Embodiment VIII above, except for the installation position of the waterproof and breathable device 8. A waterproof and breathable device 8 is provided at the other end of the sleeve channel. The waterproof and breathable device 8 is a waterproof and breathable membrane or a waterproof and breathable valve. In this embodiment, a waterproof and breathable valve is adopted, and the waterproof and breathable valve is provided on the sleeve channel outside the chamber 4, which is convenient for maintenance and replacement.

[0055] Embodiment X

[0056] This embodiment provides an electric vehicle embodiment, including a vehicle frame, a hub 3 motor provided on the vehicle frame, a tire provided on the hub 3 motor, and a battery and a controller provided on the vehicle frame. The hub 3 motor is the liquid-cooled hub 3 motor described in any of the above embodiments. This electric vehicle adopts this liquid-cooled hub 3 motor, which has good running stability, can be maintenance-free or has low maintenance costs, and has good heat dissipation performance; it can ensure the ventilation effect of the motor and the efficient heat dissipation effect of liquid cooling under various road conditions, and has high reliability.

[0057] The technical solutions provided by the present invention have been introduced in detail above. Specific examples are used in this article to elaborate on the principles and implementation manners of the present invention. The descriptions of the above embodiments are only used to help understand the method and its core idea of the present invention; the terms such as front, rear, left, right, positive, and negative in this solution are all used to clearly express the terms from a certain perspective. At the same time, for those of ordinary skill in the art, according to the idea of the present invention, there will be changes in the specific implementation manners and application scopes. In summary, the content of this specification should not be construed as a limitation on the present invention.

Claims

1. A liquid-cooled hub motor, comprising a support shaft, a stator provided on the support shaft, and a hub. The hub includes two end caps arranged oppositely, and a chamber is formed inside the hub. The stator is located inside the chamber, and a coolant is also provided inside the chamber. The stator includes a stator bracket fixed on the support shaft and a stator core provided on the outer periphery of the stator bracket. A stator inner cavity communicating with the chamber is provided inside the stator bracket. It is characterized in that, a vent hole communicating with the stator inner cavity is provided on the stator bracket; it further includes a vent passage communicating the inside of the chamber with the outside of the chamber. The vent passage includes a vent pipe; one end of the vent pipe is communicated with the vent hole through a breathing positioning member, and the other end of the vent pipe is communicated with the outside of the chamber.

2. The liquid-cooled hub motor according to claim 1, wherein, The breathing positioning member is connected to the stator bracket. A first breathing port and a second breathing port which are communicated with each other are provided on the breathing positioning member. An oil-proof protrusion is provided on the first breathing port. When the first breathing port is communicated with the vent hole, the oil-proof protrusion is inserted into the vent hole, and the oil-proof protrusion protrudes from the inner wall around the vent hole; the second breathing port is communicated with the vent pipe.

3. The liquid-cooled hub motor according to claim 2, wherein, A clamping joint is provided on the first breathing port. The clamping joint is inserted into the vent hole and clamped on the vent hole. The front end of the clamping joint enters the stator inner cavity and forms an oil-proof protrusion.

4. The liquid-cooled hub motor according to claim 2, wherein, A waterproof and breathable device is provided inside the breathing positioning member, and the waterproof and breathable device is located between the first breathing port and the second breathing port.

5. The liquid-cooled hub motor according to claim 2, wherein, The breathing positioning member includes a body. A breathing cavity is provided inside the body. The first breathing port and the second breathing port are both communicated with the breathing cavity. The first breathing port is located on the side wall of the body, and the second breathing port is located on the bottom wall of the body.

6. The liquid-cooled hub motor according to claim 1, wherein An axial channel is provided on the support shaft, and the vent pipe extends out of the chamber through the axial channel.

7. The liquid-cooled hub motor according to claim 6, characterized in that, A waterproof and breathable device is provided at the end of the vent pipe located outside the chamber.

8. The liquid-cooled hub motor according to claim 1, wherein The vent passage further includes an axial channel provided on the support shaft. One end of the axial channel is connected to the vent pipe inside the chamber, and the other end is communicated with the outside of the chamber.

9. The liquid-cooled hub motor according to claim 8, wherein A waterproof and breathable device is provided at the other end of the axial channel.

10. The liquid-cooled hub motor according to claim 8, wherein, The vent passage further includes an annular air guide cavity provided on the end cap around the support shaft. The other end of the axial channel is communicated with the annular air guide cavity, and a waterproof and breathable device is provided on the annular air guide cavity.

11. The liquid-cooled hub motor according to claim 1, characterized in that, A shaft sleeve is provided on the support shaft. A shaft sleeve channel is provided on the shaft sleeve, and the vent pipe extends out of the chamber through the shaft sleeve channel.

12. The liquid-cooled hub motor according to claim 11, wherein, A waterproof and breathable device is provided at the end of the vent pipe located outside the chamber.

13. The liquid-cooled hub motor according to claim 1, wherein, A shaft sleeve is provided on the support shaft. The vent passage further includes a shaft sleeve channel provided on the shaft sleeve. One end of the shaft sleeve channel is connected to the vent pipe inside the chamber, and the other end is communicated with the outside of the chamber.

14. The liquid-cooled hub motor according to claim 13, characterized in that, A waterproof and breathable device is provided at the other end of the shaft sleeve channel.

15. An electric vehicle, comprising a vehicle frame, a hub motor provided on the vehicle frame, a tire provided on the hub motor, and a storage battery and a controller provided on the vehicle frame, characterized in that, The hub motor is the liquid-cooled hub motor according to any one of the above claims 1-14.

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