Liquid-cooled hub motor and electric vehicle using same

Abstract

The liquid-cooled hub motor comprises a supporting shaft, a stator and a hub, the stator and the hub are arranged on the supporting shaft, the hub comprises two end covers which are oppositely arranged, a cavity is formed in the hub, the stator is located in the cavity, and cooling liquid is further arranged in the cavity; wherein one end cover is provided with an annular air guide cavity surrounding the supporting shaft, the end cover is further provided with a ventilation device, and the ventilation device is communicated with the annular air guide cavity. One end of the ventilation channel is communicated with the annular air guide cavity, and the other end of the ventilation channel is located at the stator. Compared with the prior art, the liquid-cooled hub motor provided by the utility model has the following advantages: firstly, the annular air guide cavity on the end cover is used as a ventilation channel for the inside and the outside of the cavity, and the ventilation device can be arranged on the end cover and does not need to be communicated with the ventilation device in a manner of being connected with an external air guide pipe; the problem that the ventilation device needs to be fixed to the frame or the supporting shaft is solved, the structure is simple, additional parts are not needed, and the production cost is saved.

Description

Technical Field

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

[0002] As electric bicycles and electric motorcycles become more and more popular in the market, the requirements for the performance and functions of electric vehicles are also increasing. As the core component of electric vehicles, heat dissipation is the main problem for the drive hub motor system. At present, the heat dissipation method of common electric vehicle hub motors on the market is mostly air heat dissipation, which has poor heat dissipation effect. When an electric vehicle is overloaded, the internal temperature of the motor rises rapidly. When the temperature rises to a certain level, it is enough to demagnetize the motor magnet and reduce the insulation capacity, resulting in reduced reliability of the electric vehicle motor. The heat of the motor is mainly generated by the stator. The existing hub motor stator heat dissipation mostly relies on the stator to conduct heat to the air in the hub. The air conducts heat to the outside of the motor through the rotor, that is, the hub shell. The heat dissipation efficiency is low. The internal temperature rise of the hub motor is too high, causing hidden dangers such as demagnetization of the permanent magnet and accelerated aging of the coil insulation layer; it may even burn the motor coil, causing damage to the motor and affecting driving safety.

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

[0004] Since the wheel hub motor is a sealed structure, the air pressure will increase when the internal heat is generated. Therefore, a waterproof breathable valve is generally set on the end cover of the wheel hub motor to balance the air pressure inside and outside the wheel hub motor to prevent the seal from failing due to the failure to release the pressure in time due to excessive internal air pressure, thereby causing water to enter the motor and cause damage. The characteristic of the waterproof breathable valve is that it serves as a breathable channel inside and outside the wheel hub motor under normal circumstances. When the waterproof breathable valve contacts water, the waterproof breathable membrane on it will be immediately closed to prevent water from entering the wheel hub motor. When the water on the waterproof breathable membrane dries, its breathable function can be restored.

[0005] When the coolant is injected 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, causing it to lose its waterproof and breathable functions. 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, causing oil leakage, destroying the seal of the hub motor, and reducing the service life of the motor. In addition, when the leaked coolant contacts the brake part, it will cause safety hazards. If the waterproof function is lost and water enters the motor, it will inevitably cause damage to the motor.

[0006] The authorization announcement date is January 22, 2021, and the name of the invention patent is: Oil-cooled motor. The application publication number is CN108880109B. This patent connects the inside and outside of the motor through a ventilation pipe, and a gas-liquid separation device is provided on the pipe head located 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 and breathable membrane is provided at the other end of the ventilation pipe, and the ventilation pipe extends to the outside of the motor through the channel of the control harness on the rotating shaft. The gas-liquid separation device in the invention is a three-way component, with the oil inlet at the upper end, the oil outlet at the lower end, and the inlet and outlet ports at the side ends; it can alleviate the cooling oil from entering the ventilation pipe to a certain extent, but the motor rotates at a high speed, and a large amount of cooling oil will splash onto the oil inlet. As the vehicle bumps, some of the oil will enter the ventilation pipe. Although a desiccant is provided at the front end of the water-draining breathable membrane, it can only slow down the speed at which the cooling oil contacts the waterproof breathable membrane. Once the waterproof breathable membrane contacts the cooling oil, the waterproof and breathable functions will fail.

[0007] At the same time, the ventilation pipe runs through the control harness channel, which will inevitably lead to an increase in the inner diameter of the opening on the shaft, affecting the mechanical strength of the shaft. To overcome this problem, the diameter of the shaft needs to be increased, which increases the production cost of the hub motor. The ventilation pipe and waterproof breathable device extending outside the wheel hub shell need to find a suitable fixed position on the frame, resulting in a small number of compatible models of this type of hub motor and great difficulty in assembly. The suspended waterproof breathable device can reduce the contact of the coolant with the waterproof breathable membrane to a certain extent, but when the car is overturned, the cooling oil entering the ventilation pipe will still flow to the waterproof breathable membrane, causing damage.

[0008] Another example is the utility model patent with the authorization announcement date of May 22, 2020, entitled: A new structural oil-injected motor with an efficient gas exchange system, and the application publication number CN210608830U. Although the patent adopts the method of adding a sleeve and opening a ventilation pipeline on the sleeve to avoid the problem of mechanical strength damage of the rotating shaft, the addition of the sleeve requires a larger bearing on the side where the motor is installed, which also increases the production cost of the hub motor. Secondly, the ventilation pipeline on the sleeve directly faces the inner cavity of the hub shell, and the cooling oil is more likely to splash into it. The gas exchange component needs to find a suitable fixed position on the frame, resulting in a small number of compatible models of this type of hub motor and great difficulty in assembly. The desiccant in the gas exchange component will also be damaged after the vehicle falls over, and finally leads to oil leakage. At present, there is no membrane material that is both oil-proof and breathable. It can only achieve the effect of filtering oil and prevent cooling oil from entering the ventilation pipeline in large quantities and quickly. Therefore, the oil-proof and breathable scheme of this patent still has the problems of high cost, poor reliability and easy damage. Utility Model Content

[0009] The utility model aims to overcome the deficiencies of the prior art and provide a liquid-cooled hub motor and an electric vehicle using the motor.

[0010] The main technical solution adopted by the liquid-cooled hub motor provided by the utility model is: it includes a support shaft, a stator and a hub arranged on the support shaft, the hub includes two end covers arranged oppositely, a chamber is formed in the hub, the stator is located in the chamber, and a coolant is also provided in the chamber; one of the end covers is provided with an annular air guide cavity surrounding the support shaft, and the end cover is also provided with a ventilation device, and the ventilation device is connected to the annular air guide cavity; the support shaft is provided with a ventilation channel, one end of the ventilation channel is connected to the annular air guide cavity, and the other end is located at the stator.

[0011] The liquid-cooled hub motor provided by the utility model also adopts the following auxiliary technical solutions:

[0012] Preferably, the stator includes a stator bracket fixed on the support shaft and a stator core arranged on the outer periphery of the stator bracket, and a stator inner cavity connected to the chamber is provided in the stator bracket, and one end of the air permeable channel is connected to the annular air guide cavity, and the other end is connected to the stator inner cavity.

[0013] Preferably, the air permeable passage is an intra-shaft passage located inside the support shaft, and the annular air guide cavity and the stator inner cavity are connected through the intra-shaft passage.

[0014] Preferably, the stator further comprises a sleeve disposed between the stator bracket and the supporting shaft, the sleeve being provided with an air guide port, the air guide port communicating with the inner cavity of the stator and the inner channel of the shaft.

[0015] Preferably, one end opening of the intra-shaft channel is located at the upper end of the support shaft and communicates with the annular air guide cavity, and the other end opening of the intra-shaft channel is located at the lower end of the support shaft and communicates with the stator inner cavity.

[0016] Preferably, part of the inner shaft passage close to the inner cavity of the stator is arranged obliquely in the support shaft.

[0017] Preferably, the intra-shaft channel comprises a first intra-shaft channel and a second intra-shaft channel which are connected to each other, the first intra-shaft channel is connected to the annular air guide cavity, and the second intra-shaft channel is connected to the stator cavity.

[0018] Preferably, the air permeable channel includes an intra-axial channel opened in the support shaft and an air permeable tube arranged in the chamber, one end of the intra-axial channel is connected to the annular air guide cavity, and the other end is connected to the air permeable tube.

[0019] Preferably, the stator includes a stator bracket fixed on the support shaft and a stator core arranged on the outer periphery of the stator bracket, and the stator bracket is provided with a stator inner cavity connected to the chamber, one end of the air permeable tube is connected to the shaft inner channel, and the other end is located in the stator inner cavity or on the stator.

[0020] Preferably, one end of the air-permeable tube is communicated with the inner channel of the shaft, and the other end is located in the inner cavity of the stator. An insertion hole is provided on the stator bracket, and the air-permeable tube enters the inner cavity of the stator through the insertion hole.

[0021] Preferably, a second oil seal is provided on a side of the annular air guide cavity close to the chamber, and a first oil seal is provided on a side away from the chamber, and the annular air guide cavity is located between the first oil seal and the second oil seal.

[0022] Preferably, oil absorbing material is provided in the air permeable channel and / or the annular air guiding cavity.

[0023] Preferably, the end cover comprises a cover body and a shaft cylinder arranged in the middle of the cover body, a bearing and an oil seal are arranged in the shaft cylinder, the bearing and the oil seal sleeve are arranged on the support shaft, and the annular air guide cavity is located between the bearing and the oil seal.

[0024] Preferably, an oil blocking groove is provided on the cover body around the outer side of the shaft cylinder.

[0025] Preferably, the distance from the shaft cylinder to the stator is greater than the distance from the connecting portion between the shaft cylinder and the cover body to the stator.

[0026] Preferably, the end of the air permeable tube located in the inner cavity of the stator is located between the axis and the outer edge of the stator.

[0027] Preferably, an oleophobic component is provided inside the air permeable channel or at the end of the air permeable channel.

[0028] Preferably, a first one-way valve is provided in the air permeable channel, and a second one-way valve is provided between the annular air guide cavity and the chamber.

[0029] Preferably, it also includes a cable connected to the stator, and a cable channel connecting the inside and outside of the chamber is provided on the support shaft, one end of the cable is connected to the stator, and the other end extends out of the chamber through the cable channel; the cable channel is provided on one side of the support shaft, and the air permeable channel is provided on the other side of the support shaft.

[0030] The main technical scheme adopted by the electric vehicle provided by the utility model is: it includes a frame, a hub motor arranged on the frame, a tire arranged on the hub motor, and a battery and a controller arranged on the frame. The hub motor includes a support shaft, a stator and a hub arranged on the support shaft. The hub includes two end covers arranged oppositely, a chamber is formed in the hub, the stator is located in the chamber, and a coolant is also provided in the chamber; one of the end covers is provided with an annular air guide cavity surrounding the support shaft, and the end cover is also provided with a ventilation device, and the ventilation device is connected to the annular air guide cavity; the support shaft is provided with a ventilation channel, one end of the ventilation channel is connected to the annular air guide cavity, and the other end is located at the stator.

[0031] Compared with the existing technologies of the liquid-cooled hub motor and electric vehicle provided by the utility model, the advantages are as follows: first, the annular air guide cavity on the end cover is used as a ventilation channel between the inside and outside of the chamber, and the ventilation device can be arranged on the end cover without the need to use an external air guide pipe to communicate with the ventilation device; the problem that the ventilation device needs to be fixed to the frame or the support shaft is eliminated, the structure is simple, no additional parts are required, and the production cost is saved; secondly, a channel or a partial channel connecting the annular air guide cavity and the chamber is opened on the support shaft, which ensures that the annular air guide cavity can always maintain a connected state when rotating with the end cover, the structure is simple and ingenious, and the reliability is high; finally, the utility model has good operating stability, can be maintenance-free, or the maintenance cost is low, and the heat dissipation performance is good; it can ensure the ventilation effect of the motor and the efficient heat dissipation effect of liquid cooling under various road conditions, and the reliability is high. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 It is a cross-sectional view of the liquid-cooled hub motor in the first embodiment of the present utility model.

[0033] Figure 2 It is a cross-sectional view of the liquid-cooled hub motor in the second embodiment of the present utility model.

[0034] Figure 3 It is a cross-sectional view of the liquid-cooled hub motor of the utility model when double oil seals, namely the first oil seal and the second oil seal, are installed.

[0035] Figure 4 It is a cross-sectional view of the installation of the first one-way valve and the second one-way valve in the liquid-cooled hub motor of the utility model.

[0036] Figure 5 This is a structural diagram of the liquid-cooled hub motor of the utility model.

[0037] Figure 6 This is a structural diagram of the end cover of the liquid-cooled hub motor of the present utility model. DETAILED DESCRIPTION

[0038] In order to make the above-mentioned purposes, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0039] See also Figures 1 to 6According to the embodiment of the liquid-cooled hub motor provided by the utility model, it includes a support shaft 1, a stator 2 and a hub 3 arranged on the support shaft 1, the hub 3 includes two end covers 32 arranged opposite to each other, a chamber 4 is formed in the hub 3, the stator 2 is located in the chamber 4, and a coolant 5 is also arranged in the chamber 4; one of the end covers 32 is provided with an annular air guide cavity 33 surrounding the support shaft 1, and the end cover 32 is also provided with a breathable device 6, and the breathable device 6 is connected with the annular air guide cavity 33; the support shaft 1 is provided with a breathable channel 101, one end of the breathable channel 101 is connected with the annular air guide cavity 33, and the other end is located at the stator 2. The hub 3 generally includes a rim 31 and end covers 32 arranged on both sides of the rim 31, and the three together constitute 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 described in detail here. In specific use, one of the two end covers 32 is provided with an oil filling port (not shown in the figure), and the oil filling port is provided with a detachable bolt to facilitate the filling or oil change in the chamber 4. The volume of the coolant 5 is 5%-20% of the volume of the chamber 4. The preferred embodiment is 10%. The ventilation device 6 can adopt a waterproof breathable valve in the prior art, that is, the valve has a breathable function under normal circumstances, and can be closed after contacting water to prevent water from entering the chamber 4. The end cover 32 is provided with a valve hole connected to the annular air guide cavity 33, and the waterproof breathable valve is installed on the valve hole. The coolant 5 uses cooling oil, which can generally be: insulating cooling oil. Compared with the prior art, the present solution, firstly, adopts the annular air guide cavity 33 on the end cover 32 as the ventilation channel between the inside and outside of the chamber 4, and the ventilation device 6 can be arranged on the end cover 32 without adopting an external air guide pipe to communicate with the ventilation device 6; the problem that the ventilation device 6 needs to be fixed to the frame or to the support shaft 1 is eliminated, the structure is simple, no additional parts are required, and the production cost is saved; secondly, a channel or a partial channel connecting the annular air guide cavity 33 and the chamber 4 is opened on the support shaft 1, which ensures that the annular air guide cavity 33 can always be connected when rotating with the end cover 32, the structure is simple and ingenious, and the reliability is high; finally, the utility model has good operating stability, can be maintenance-free, or the maintenance cost is low, and the heat dissipation performance is good; it can ensure the ventilation effect of the motor and the efficient heat dissipation effect of liquid cooling under various road conditions, and the reliability is high.

[0040] See also Figures 1 to 4According to the above-mentioned embodiment of the utility model, the stator 2 includes a stator bracket 21 fixed on the support shaft 1 and a stator core 22 arranged on the outer periphery of the stator bracket 21. The stator bracket 21 is provided with a stator inner cavity 24 communicating with the chamber 4; one end of the air permeable channel 101 is communicated with the annular air guide cavity 33, and the other end is communicated with the stator inner cavity 24. The stator bracket 21 includes a first bracket monolithic piece and a second bracket monolithic piece that are buckled together, and the stator inner cavity 24 is formed between the first bracket monolithic piece and the second bracket monolithic piece. The stator bracket 21 is provided with a through hole connecting the stator inner cavity 24 and the chamber 4, and the through hole can be a positioning hole or other process hole in the processing of the stator 2. This structure cleverly arranges the ventilation area inside the chamber 4 and outside the hub 3 motor in the stator inner cavity 24, so that the coolant 5 will not splash into the stator inner cavity 24 when the motor is working, thereby preventing the coolant 5 from entering the ventilation channel 101 and the annular air guide cavity 33, ensuring the stability of the ventilation device 6, and also ensuring the stability and reliability of the motor operation.

[0041] Embodiment 1

[0042] See also Figure 1 According to the above-mentioned embodiment of the utility model, the air permeable channel 101 is an inner shaft channel 11 located inside the support shaft 1, and the annular air guide cavity 33 and the stator inner cavity 24 are connected through the inner shaft channel 11. Drilling the inner shaft channel 11 in the support shaft 1 reduces the sealing steps of the pipeline, has high reliability and good air permeability; compared with the prior art, no parts are added, the structure is simple, the assembly efficiency is high, and only the step of turning the hole in the shaft is added. Compared with the existing liquid-cooled hub 3 motor, the production cost is extremely low, and the adaptability to the existing production line is extremely high, which reduces the investment cost of the production line, thereby reducing the production cost of the product. The stator 2 also includes a sleeve 23 arranged between the stator bracket 21 and the support shaft 1, and the sleeve 23 is provided with an air guide port 231, which connects the stator inner cavity 24 with the inner shaft channel 11. The air guide port can be one or more, or the projection of the air guide port is a waist-shaped hole, which avoids the connection failure caused by the installation error and improves the reliability and stability of the product.

[0043] See also Figure 1According to the above-mentioned embodiment of the utility model, one end opening of the inner shaft channel 11 is located at the upper end of the support shaft 1 and communicates with the annular air guide cavity 33, and the other end opening of the inner shaft channel 11 is located at the lower end of the support shaft 1 and communicates with the stator inner cavity 24. The openings on both sides of the inner shaft channel 11 are respectively located on the upper and lower sides of the support shaft 1, which facilitates drilling. At the same time, the opening located in the stator inner cavity 24 is downward, which can prevent the coolant 5 from entering the inner shaft channel 11 or the annular air guide cavity 33 through the opening. Even if a small amount of coolant 5 enters, the coolant 5 will automatically be discharged under the action of gravity because the opening is downward, thereby improving the reliability of the product. The part of the inner shaft channel 11 close to the stator inner cavity 24 is tilted in the support shaft 1; and the lowest point of the tilted section is close to the stator inner cavity 24. Even if part of the coolant 5 enters the inner shaft channel 11, due to the tilt of the inner shaft channel 11, the coolant 5 slides out of the inner shaft channel 11 under the action of gravity.

[0044] See also Figure 1 According to the above-mentioned embodiment of the utility model, the inner shaft channel 11 includes a first inner shaft channel 111 and a second inner shaft channel 112 which are connected to each other. The first inner shaft channel 111 is connected to the annular air guide cavity 33, and the second inner shaft channel 112 is connected to the stator inner cavity 24. An angle is formed between the first inner shaft channel 111 and the second inner shaft channel 112. The second inner shaft channel 112 is tiltedly arranged in the support shaft 1. The inner shaft channel 11 adopts a two-stage structure, which is more convenient to process, reduces the difficulty of drilling, and has little effect on the mechanical strength of the support shaft 1.

[0045] See also Figure 3 According to the above-mentioned embodiment of the utility model, a second oil seal 82 is provided on the side of the annular air guide cavity 33 close to the chamber 4, and a first oil seal 81 is provided on the side away from the chamber 4, and the annular air guide cavity 33 is located between the first oil seal 81 and the second oil seal 82. The oil seals 8 are provided on both sides of the annular air guide cavity 33, which greatly reduces the risk of the coolant 5 entering the annular air guide cavity 33 through the support shaft 1, and improves the reliability and stability of the air permeable device 6.

[0046] According to the above-mentioned embodiment of the utility model, an oil-absorbing material is provided in the air permeable channel 101 and / or the annular air guide cavity 33. Preferably, the oil-absorbing material is provided in the annular air guide cavity 33, and the oil-absorbing material can be oil-absorbing paper, activated carbon, sponge, etc. The oil-absorbing material will not cause blockage to the air permeable channel 101 and the annular air guide cavity 33. Even if a small amount of coolant 5 enters the annular air guide cavity 33 or approaches the annular air guide cavity 33, the oil-absorbing material can absorb the coolant 5 that cannot return to the chamber 4, thereby preventing the coolant 5 from causing pollution and damage to the air permeable device 6, thereby ensuring the service life and reliability of the air permeable device 6.

[0047] See also Figure 1 and Figure 6According to the above-mentioned embodiment of the utility model, the end cover 32 includes a cover body and a shaft cylinder 321 arranged in the middle of the cover body, a bearing 7 and an oil seal 8 are arranged in the shaft cylinder 321, the bearing 7 and the oil seal 8 are sleeved on the support shaft 1, and the annular air guide cavity 33 is located between the bearing 7 and the oil seal 8. In specific use, a sealing ring can also be arranged between the shaft cylinder 321 and the bearing 7, and between the bearing 7 and the support shaft 1 to improve the sealing performance and prevent the coolant 5 from entering the annular air permeable cavity through the bearing 7. The bearing 7 is located between the chamber 4 and the annular air guide cavity 33. This solution cleverly utilizes the space between the bearing 7 and the oil seal 8 as an intermediate cavity for air circulation inside and outside the chamber 4, so that the air permeable device 6 arranged on the end cover 32 can continue to remain on the end cover 32. Even in a rotating state, it does not affect the ventilation requirements of the wheel hub 3 motor. Compared with the prior art, this structure does not require additional parts and process steps, which greatly reduces the production cost and reliability of the product.

[0048] See also Figure 1 and Figure 6 According to the above-mentioned embodiment of the utility model, an oil blocking groove 322 is provided on the cover body around the outer side of the shaft cylinder 321. When the electric vehicle or the motor is in a tilted state, the oil blocking groove 322 can accumulate the coolant 5 to prevent the coolant 5 from contacting the bearing 7 or the inside of the shaft cylinder 321, and reduce the risk of the coolant 5 entering the annular air guide cavity 33 through the shaft cylinder 321. It is also possible to adopt a distance from the shaft cylinder 321 to the stator 2 that is greater than the distance from the shaft cylinder 321 to the connecting part of the cover body to the stator 2. Its effect is the same as that of the above-mentioned oil blocking groove 322, and will not be described in detail here.

[0049] According to the above-mentioned embodiment of the utility model, an oleophobic component is provided in the air permeable channel 101 or at the end of the air permeable channel 101. The oleophobic component used in this embodiment is preferably an oleophobic film, which greatly reduces the risk of the coolant 5 entering the air permeable channel 101 or the annular air guide cavity 33.

[0050] See also Figure 4 According to the above-mentioned embodiment of the utility model, a first one-way valve 91 is provided in the air permeable channel 101, and a second one-way valve 92 is provided between the annular air guide cavity 33 and the chamber 4. The first one-way valve 91 is opened when the chamber 4 is in the exhaust state, and is closed when the chamber 4 is in the intake state; the second one-way valve 92 is opened when the chamber 4 is in the intake state, and is closed when the chamber 4 is in the exhaust state. This solution can friendly prevent the coolant 5 from entering the annular air guide cavity 33 through the air permeable channel 101. At the same time, when the chamber 4 takes in air through the second one-way valve 92, even if there is a small amount of coolant 5 in the annular air guide cavity 33, it can flow back to the chamber 4 through the second one-way valve 92 under the action of the negative pressure in the chamber 4, thereby preventing the coolant 5 from contacting the air permeable device 6.

[0051] See also Figures 1 to 4According to the above-mentioned embodiment of the utility model, it also includes a cable connected to the stator 2, and the support shaft 1 is provided with a cable channel 12 connecting the inside and outside of the chamber 4, one end of the cable is connected to the stator 2, and the other end extends out of the chamber 4 through the cable channel 12; the cable channel 12 is provided on one side of the support shaft 1, and the air-permeable channel 101 is provided on the other side of the support shaft 1. The air-permeable channel 101 and the cable channel 12 are respectively provided on both sides of the support shaft 1, which ensures the mechanical strength of the support shaft 1, and there is no need to increase the diameter of the support shaft 1 or set a sleeve, saving production costs and reducing production difficulty.

[0052] According to the electric vehicle embodiment provided by the utility model, it includes a frame, a hub motor arranged on the frame, a tire arranged on the hub motor, and a battery and a controller arranged on the frame, wherein the hub motor is the liquid-cooled hub motor described in the above embodiment. The electric vehicle adopts the liquid-cooled hub motor, has good running stability, can be maintenance-free, or has low maintenance cost, and has good heat dissipation performance; it can ensure the ventilation effect of the motor under various road conditions, and the efficient heat dissipation effect of liquid cooling, and has high reliability.

[0053] Embodiment 2

[0054] See also Figures 2 to 4 The structure of this embodiment is substantially the same as that of the first embodiment, except that the structure of the air permeable channel 101 is different. The air permeable channel 101 in this embodiment includes an inner shaft channel 11 provided in the support shaft 1 and an air permeable tube 10 provided in the chamber 4. One end of the inner shaft channel 11 is connected to the annular air guide cavity 33, and the other end is connected to the air permeable tube 10. That is, the connection between the air permeable tube 10 and the inner shaft channel 11 is located in the chamber 4. By adopting the air permeable channel 101, the length of the inner shaft channel 11 is reduced, the drilling process of the inner shaft channel 11 is reduced, the production efficiency is improved, and the production cost is reduced.

[0055] See also Figures 2 to 4 According to the above-mentioned embodiment of the utility model, one end of the air tube 10 is connected to the inner channel 11 of the shaft, and the other end is located in the inner cavity 24 of the stator. An insertion hole 211 is provided on the stator bracket 21, and the air tube 10 enters the inner cavity 24 of the stator through the insertion hole 211. To ensure reliability, the air tube 10 and the inner channel 11 of the shaft can be sealed by gluing. The stator bracket 21 is provided with a plurality of process holes such as positioning holes, which ensure the communication between the inner cavity 24 of the stator and the chamber 4; the air tube 10 can also be inserted into the inner cavity 24 of the stator through one of the process holes. The air tube 10 is directly inserted into the inner cavity 24 of the stator through the insertion hole 211, which is simple to operate and easy to assemble. To further ensure the reliability between the air tube 10 and the stator 2, the air tube 10 and the stator 2 can be reinforced by a firmware component.

[0056] See also Figures 2 to 4According to the above-mentioned embodiment of the utility model, the end of the air-permeable tube 10 located in the stator inner cavity 24 is located between the axis and the outer edge of the stator 2. Even if the coolant 5 splashes into the stator inner cavity 24 through the process hole, the coolant 5 can be prevented from contacting the mouth of the air-permeable tube 10 to the greatest extent, thereby ensuring the reliability of the product.

[0057] Embodiment 3

[0058] The structure of this embodiment is roughly the same as that of the above-mentioned embodiment 2, except that the assembly structure of the other end of the air vent tube 10 and the stator 2 is different. One end of the air vent tube 10 is connected to the shaft inner channel 11, and the other end is located on the stator 2. The difference between this embodiment and embodiment 2 is that the air vent tube 10 is not inserted into the stator inner cavity 24, but is fixed on the stator 2, preferably fixed on the stator bracket 21; it can be fixed on the stator bracket 21 through a clamping structure, for example, a clamping hole is provided on the stator bracket 21, and a clamping pipe head is provided on the air vent tube, and the clamping pipe head cooperates with the clamping hole. This structure is easy to assemble. Compared with the prior art, the air vent device 6 can be set on the hub 3, with a simple structure and good adaptability.

[0059] The technical solution provided by the present invention is introduced in detail above. Specific examples are used in this article to illustrate the principle and implementation mode of the present invention. The description of the above embodiments is only used to help understand the method and core idea of ​​the present invention. The words such as front, back, left, right, positive and negative in this solution are all words for clear expression from a certain perspective. At the same time, for general technical personnel in this field, according to the idea of ​​the present invention, there will be changes in the specific implementation mode and application scope. In summary, the content of this specification should not be understood as a limitation on the present invention.

Claims

1. A liquid-cooled hub motor, comprising a support shaft (1), a stator (2) and a hub (3) arranged on the support shaft (1), the hub (3) comprising two end covers (32) arranged opposite to each other, a chamber (4) formed in the hub (3), the stator (2) being located in the chamber (4), and a cooling liquid (5) being arranged in the chamber (4); It is characterized in that An annular air guide cavity (33) surrounding the support shaft (1) is provided on one of the end covers (32), and a venting device (6) is also provided on the end cover (32), and the venting device (6) is in communication with the annular air guide cavity (33); an air permeable channel (101) is provided on the support shaft (1), and one end of the air permeable channel (101) is in communication with the annular air guide cavity (33), and the other end is located at the stator (2).

2. The liquid-cooled hub motor according to claim 1, characterized in that: The stator (2) comprises a stator support (21) fixed on the support shaft (1) and a stator core (22) arranged on the outer periphery of the stator support (21); a stator inner cavity (24) communicating with the chamber (4) is arranged in the stator support (21); one end of the air permeable channel (101) is communicated with the annular air guide cavity (33), and the other end is communicated with the stator inner cavity (24).

3. The liquid-cooled hub motor according to claim 2, characterized in that: The air permeable channel (101) is an inner shaft channel (11) located inside the support shaft (1), and the annular air guide cavity (33) and the stator inner cavity (24) are connected through the inner shaft channel (11).

4. The liquid-cooled hub motor according to claim 3, characterized in that: The stator (2) also includes a shaft sleeve (23) arranged between the stator bracket (21) and the support shaft (1), and the shaft sleeve (23) is provided with an air guide port (231), and the air guide port (231) communicates with the stator inner cavity (24) and the inner shaft channel (11).

5. The liquid-cooled hub motor according to claim 3, characterized in that: One end opening of the intra-axial channel (11) is located at the upper end of the support shaft (1) and is in communication with the annular air guide cavity (33), and the other end opening of the intra-axial channel (11) is located at the lower end of the support shaft (1) and is in communication with the stator inner cavity (24).

6. The liquid-cooled hub motor according to claim 3, characterized in that: A portion of the inner shaft passage (11) close to the stator inner cavity (24) is arranged in an inclined manner in the support shaft (1).

7. The liquid-cooled hub motor according to claim 3, characterized in that: The in-shaft channel (11) comprises a first in-shaft channel (111) and a second in-shaft channel (112) which are connected to each other; the first in-shaft channel (111) is connected to the annular air guide cavity (33), and the second in-shaft channel (112) is connected to the stator cavity (24).

8. The liquid-cooled hub motor according to claim 1, characterized in that: The air permeable channel (101) comprises an in-shaft channel (11) opened in the support shaft (1) and an air permeable tube (10) arranged in the chamber (4); one end of the in-shaft channel (11) is connected to the annular air guide cavity (33), and the other end is connected to the air permeable tube (10).

9. The liquid-cooled hub motor according to claim 8, characterized in that: The stator (2) comprises a stator bracket (21) fixed on the support shaft (1) and a stator core (22) arranged on the outer periphery of the stator bracket (21); a stator inner cavity (24) communicating with the chamber (4) is arranged in the stator bracket (21); one end of the air permeable tube is communicated with the shaft inner channel (11), and the other end is located in the stator inner cavity (24) or on the stator (2).

10. The liquid-cooled hub motor according to claim 9, characterized in that: One end of the air permeable tube (10) is in communication with the shaft inner channel (11), and the other end is located in the stator inner cavity (24). An insertion hole (211) is provided on the stator bracket (21), and the air permeable tube (10) enters the stator inner cavity (24) through the insertion hole (211).

11. The liquid-cooled hub motor according to any one of claims 1 to 10, characterized in that: A second oil seal (82) is provided on a side of the annular air guide cavity (33) close to the chamber (4), and a first oil seal (81) is provided on a side away from the chamber (4); the annular air guide cavity (33) is located between the first oil seal (81) and the second oil seal (82).

12. The liquid-cooled hub motor according to any one of claims 1 to 10, characterized in that: Oil absorbing material is arranged in the air permeable channel (101) and / or the annular air guide cavity (33).

13. The liquid-cooled hub motor according to any one of claims 1 to 10, characterized in that: The end cover (32) comprises a cover body and a shaft cylinder (321) arranged in the middle of the cover body, a bearing (7) and an oil seal (8) are arranged in the shaft cylinder (321), the bearing (7) and the oil seal (8) are sleeved on the support shaft (1), and the annular air guide cavity (33) is located between the bearing (7) and the oil seal (8).

14. The liquid-cooled hub motor according to claim 13, characterized in that: An oil blocking groove (322) is provided on the cover body around the outer side of the shaft cylinder (321).

15. The liquid-cooled hub motor according to claim 13, characterized in that: The distance between the shaft cylinder (321) and the stator (2) is greater than the distance between the shaft cylinder (321) and the cover body connection portion and the stator (2).

16. The liquid-cooled hub motor according to any one of claims 1 to 10, characterized in that: The end of the air permeable tube located in the inner cavity (24) of the stator is located between the axis and the outer edge of the stator (2).

17. The liquid-cooled hub motor according to any one of claims 1 to 10, characterized in that: An oleophobic component is provided inside the air permeable channel (101) or at the end of the air permeable channel (101).

18. The liquid-cooled hub motor according to any one of claims 1 to 10, characterized in that: A first one-way valve (91) is provided in the air permeable channel (101), and a second one-way valve (92) is provided between the annular air guide cavity (33) and the chamber (4).

19. The liquid-cooled hub motor according to any one of claims 1 to 10, characterized in that: It also includes a cable connected to the stator (2), a cable channel (12) communicating with the inside and outside of the chamber (4) is provided on the support shaft (1), one end of the cable is connected to the stator (2), and the other end extends out of the chamber (4) through the cable channel (12); The cable channel (12) is arranged on one side of the support shaft (1), and the air permeable channel (101) is arranged on the other side of the support shaft (1).

20. An electric vehicle, comprising a frame, a hub motor mounted on the frame, a tire mounted on the hub motor, and a battery and a controller mounted on the frame, characterized in that: The hub motor is a liquid-cooled hub motor as described in any one of claims 1 to 19.

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