Axial flux motor with self-heat dissipation based on axial suction force driving

Abstract

The utility model belongs to motor technical field, the self -cooling axial magnetic flux motor based on axial suction force drive provided in the application, it includes: shell, motor shaft, work cooling structure and axial suction force drive mechanism, motor shaft, work cooling structure and axial suction force drive mechanism set up in the shell, wherein, the shell and motor shaft are connected through bearing, axial suction force drive mechanism includes stator and rotor, motor shaft is worn in rotor, and rotor and motor shaft are connected through slide key, motor shaft is worn in stator, stator and the box body fixed connection of shell, rotor can move along the axial direction of motor shaft through slide key, work cooling structure includes first cavity and second cavity, and the first cavity between rotor, stator and the box body of shell is formed, the inside of stator is provided with second cavity, first cavity and second cavity are linked together, and the axial suction force between rotor and stator provides power for the flow of cooling liquid.

Description

Technical Field

[0001] This utility model belongs to the field of motor technology, and in particular relates to a self-heating axial flux motor based on axial attraction drive. Background Technology

[0002] Axial flux motors, also known as axial magnetic field motors or disc motors, differ from ordinary motors in that their magnetic flux direction is axial, the current-carrying conductors are placed radially, and both the stator and rotor cores have a disc structure. Due to their high power density, compact structure, and efficient energy conversion characteristics, axial flux motors are widely used in high-precision, high-load applications such as electric vehicles and industrial drives. The structures of axial flux motors typically include: one stator and one rotor; two rotors with one stator in between; two stators with one rotor in between; and multiple stators and multiple rotors interleaved.

[0003] Existing technologies have the following drawbacks and shortcomings: Like traditional brushless DC motors, axial flux motors also generate heat during operation. Furthermore, with the continuous increase in motor power density, the amount of heat generated during operation increases dramatically. Insufficient heat dissipation will lead to problems such as excessive winding temperature rise and permanent magnet demagnetization, seriously affecting motor performance and lifespan. To effectively dissipate heat, various heat dissipation methods have been proposed for different motors. Currently, heat dissipation solutions for axial flux motors mainly include the following two categories: air cooling: forced convection cooling via an external fan, but with low heat dissipation efficiency, making it difficult to meet the demands of high-power operating conditions; liquid cooling: using an oil-cooled or water-cooled circulation system, with an external pump driving the cooling medium to flow through the motor's interior. While this solution has higher heat dissipation efficiency, it requires an independent oil pump, complex piping, and sealing structures, resulting in high system cost, large space occupation, and a risk of leakage.

[0004] Meanwhile, during the operation of an axial flux motor, the interaction of the magnetic fields between the stator and rotor generates an axial attraction force. In traditional designs, this force is considered a harmful mechanical load and must be borne by high-rigidity bearings or structural components, which not only increases manufacturing costs but may also lead to bearing wear and vibration problems. Utility Model Content

[0005] This invention provides a self-heating axial flux motor based on axial suction drive, which solves the problems of low motor heat dissipation efficiency and bearing wear caused by axial suction.

[0006] To achieve the above objectives, this application provides the following technical solution:

[0007] A self-cooling axial flux motor based on axial suction drive includes: a housing, a motor shaft, a working cooling structure, and an axial suction drive mechanism; the motor shaft, the working cooling structure, and the axial suction drive mechanism are disposed in the housing, wherein the housing and the motor shaft are connected by bearings; the axial suction drive mechanism includes a stator and a rotor; the motor shaft passes through the rotor, and the rotor and the motor shaft are connected by a sliding key; the motor shaft passes through the stator; the stator and the housing are fixedly connected; the rotor can move along the axial direction of the motor shaft via a sliding key; the working cooling structure includes a first cavity and a second cavity; the first cavity is formed between the rotor, the stator, and the housing; the second cavity is disposed inside the stator; the first cavity and the second cavity are connected and contain coolant; the outer wall of the rotor is provided with a thickened section in the radial direction away from the axial direction of the motor shaft; in the first cavity, the thickened section of the rotor and the end outer wall of the stator constitute a slit throttling valve to realize unidirectional flow of coolant.

[0008] Furthermore, in the self-heating axial flux motor described above, a stator core is provided in the middle of the stator, the stator core includes a stator yoke, and the thickness of the stator yoke is in the range of 8-15mm; the thickened section and the end outer wall of the stator yoke form a slit throttling valve.

[0009] Furthermore, in the self-cooling axial flux motor described above, the range of movement of the rotor along the axial direction of the motor shaft does not exceed 3mm; an elastic device is provided between the rotor and the stator for the rotor to reset.

[0010] Furthermore, in the self-cooling axial flux motor described above, one rotor is provided between every two adjacent stators or one stator is provided between every two adjacent rotors.

[0011] Furthermore, in the self-heating axial flux motor described above, the distance between the thickened section and the end outer wall of the stator ranges from 5 to 5000 μm.

[0012] Furthermore, in the self-cooling axial flux motor described above, a fan is provided on the housing or external device for heat dissipation.

[0013] Furthermore, in the self-heating axial flux motor described above, a sealing ring is fitted on the outer side of the stator, and the sealing ring is arranged along the circumference of the stator.

[0014] Furthermore, in the self-cooling axial flux motor described above, the second cavity includes a first flow channel and a second flow channel. The first flow channel is parallel to the motor shaft and communicates with the first cavity; the second flow channel is perpendicular to the first flow channel.

[0015] Furthermore, in the self-cooling axial flux motor described above, the working cooling structure also includes a one-way valve, which is disposed on the outside of the stator. One end of the second flow channel is connected to the first flow channel, and the other end is connected to the one-way valve.

[0016] Furthermore, in the self-cooling axial flux motor described above, the one-way valve includes a valve core, a valve spring, and an oil seal bolt. The valve core is connected to the second flow channel and is used to switch the passage from the first cavity to the second flow channel of the second cavity using the valve spring. One end of the valve spring is connected to the valve core, and the other end is connected to the oil seal bolt. The oil seal bolt is threadedly connected to the outer casing for the injection and discharge of coolant.

[0017] The technical solution provided in this application has the following beneficial effects:

[0018] This application provides a self-cooling axial flux motor driven by axial attraction. The thickened section of the rotor and the stator form a slit throttling valve, enabling unidirectional flow of coolant. This allows heat from the rotor and stator to be transferred to the casing for dissipation, eliminating the need for an external cooling oil pump while achieving the same cooling effect for the rotor and stator. This reduces equipment size and saves costs. The coolant channels in the working cooling structure are integrated with the motor, reducing the risk of coolant leakage. The cooperation between the rotor and stator converts harmful axial attraction into heat dissipation power, protecting the motor and extending bearing life. Attached Figure Description

[0019] Figure 1 An exploded view of a self-heating axial flux motor driven by axial attraction provided in this application;

[0020] Figure 2 A front view of the structure of a self-heating axial flux motor driven by axial attraction provided in this application;

[0021] Figure 3 for Figure 2 A cross-sectional view along the AA direction;

[0022] Figure 4 A partially enlarged cross-sectional view of a self-heating axial flux motor driven by axial attraction provided in this application;

[0023] Figure 5 A partially enlarged view of the slit of a self-heating axial flux motor driven by axial attraction provided in this application;

[0024] Explanation of reference numerals in the attached diagram: End cap 1, Bearing 2, Motor shaft 3, First rotor 4, First rotor permanent magnet 4b, Gasket 5, Return spring 6, Sealing ring 7, Stator coil winding 8, Stator 9, Elastic retaining ring 10, Second rotor 11, Housing 12, Oil seal bolt 13, Valve core 14, Valve spring 15, Thickened section 16, Slit 17, First cavity 18, Second cavity 19, Stator end outer wall 20, First flow channel 21, Second flow channel 22. Detailed Implementation

[0025] To make the objectives, technical solutions, and advantages of this utility model clearer, the embodiments of this utility model will be further described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this utility model, and not all of them. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model.

[0026] In the description of this utility model, it should be noted that the terms "upper," "lower," "left," "right," "inner," "outer," "front end," "rear end," "both ends," "one end," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0027] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installed," "equipped with," and "connected," etc., should be interpreted broadly. For example, "connected" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be a connection within two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0028] See attached document Figure 1-5 This application provides a detailed description of a self-heating axial flux motor based on axial attraction drive, wherein... Figure 1 An exploded view of a self-heating axial flux motor driven by axial attraction provided in this application; Figure 2 A front view of the structure of a self-heating axial flux motor driven by axial attraction provided in this application; Figure 3 for Figure 2 A cross-sectional view along the AA direction; Figure 4 A partially enlarged cross-sectional view of a self-heating axial flux motor driven by axial attraction provided in this application; Figure 5 A partially enlarged view of the slit of a self-heating axial flux motor driven by axial attraction provided in this application.

[0029] like Figure 1 As shown, this application provides a self-heating axial flux motor based on axial suction drive, including: a housing, a motor shaft 3, a working cooling structure, and an axial suction drive mechanism;

[0030] The motor shaft 3, the working cooling structure, and the axial suction drive mechanism are housed in the housing, wherein the housing and the motor shaft 3 are connected by bearing 2;

[0031] The axial suction drive mechanism includes a stator 9 and a rotor; a motor shaft 3 passes through the rotor, and the rotor and the motor shaft 3 are connected by a sliding key; the motor shaft 3 passes through the stator 9; the stator 9 and the housing 12 of the outer casing are fixedly connected; the rotor can move along the axial direction of the motor shaft 3 by a sliding key;

[0032] The working cooling structure includes a first cavity 18 and a second cavity 19;

[0033] A first cavity 18 is formed between the rotor, stator 9, and housing 12; a second cavity 19 is provided inside the stator 9; the first cavity 18 and the second cavity 19 are connected and contain coolant; the axial suction force generated between the rotor and stator provides power for the flow of coolant; the thickened section is provided on the outer wall of the rotor in the radial direction away from the axis of the motor shaft; in the first cavity, the thickened section of the rotor and the end outer wall 20 of the stator form a slit, constituting a slit throttle valve, which enables unidirectional flow of coolant.

[0034] This application provides a self-cooling axial flux motor driven by axial attraction. The thickened section of the rotor and the outer wall 20 of the stator end form a slit throttling valve, enabling unidirectional flow of coolant. This allows heat from the rotor and stator to be transferred to the outer casing for dissipation, eliminating the need for an external cooling oil pump while achieving the same cooling effect for the rotor and stator. This reduces equipment size and saves costs. The coolant channel in the working cooling structure is integrated with the motor, reducing the risk of coolant leakage. The cooperation between the rotor and stator converts harmful axial attraction into heat dissipation power, protecting the motor and extending the life of the bearings.

[0035] like Figures 1 to 4As shown, this application provides a self-heating axial flux motor based on axial suction drive, including the housing, motor shaft 3, working cooling structure and axial suction drive mechanism mentioned in the above embodiments;

[0036] The motor shaft 3 is used for power output; the housing and the motor shaft 3 are connected by bearings 2, and the housing supports the motor shaft 3 through the bearings 2, with the motor shaft 3 passing through the housing; the housing includes an end cover 1 and a box 12, the end cover 1 is located at one open end of the box 12 and is fixed to the box 12 by bolts, for enclosing and protecting the components inside the box 12; the box 12 has a columnar structure, preferably a cylindrical structure, with one end open and the other end closed, forming an accommodating space for carrying the components; the other end of the box 12 is also provided with a bearing 2 for supporting and fixing the motor shaft 3; the end cover 1 has a circular cross-section, with a hole in the middle, through which the motor shaft 3 passes; the motor shaft 3 passes through the box 12 and the end cover 1, and the motor shaft 3, the box 12 and the end cover 1 are coaxially arranged, with the end cover 1 and the motor shaft 3 connected by bearings 2, which support the motor shaft 3. The outer casing protects and supports the motor shaft 3, the working cooling structure, and the various components of the axial suction drive mechanism. It should be noted that the part furthest from the axis of the motor shaft 3 is the outer side, and the part closest to the axis of the motor shaft 3 is the inner side.

[0037] The housing 12 houses the stator 9 and rotor of the axial suction drive mechanism. The rotor extends along the axis of the motor shaft 3 and can move along the axis of the motor shaft 3 with a short stroke. The rotor is disc-shaped with a hole in the middle for the motor shaft 3 to pass through, i.e., the motor shaft 3 passes through the middle of the rotor. The rotor and the motor shaft 3 are connected by a key. In one specific embodiment, the rotor and the motor shaft 3 are connected by a sliding key, which allows the rotor to move axially on the motor shaft 3 to a certain extent. That is, the rotor can move along the axis of the motor shaft 3 via the sliding key. The range of movement of the rotor along the axis of the motor shaft 3 does not exceed 3mm, and the length of the sliding key is not less than 3mm, for example, 3, 6, 8, 10, or 12mm. The distance between the rotor and the stator in the axial flux motor is the air gap length, which is typically within the range of... The diameter of the stator is 0.1mm-5mm, for example, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1.0, 1.1, 1.2, 1.3, 1.4, 1.5, 1.7, 1.8, 1.9, 2.0, 2.2, 2.3, 2.5, 2.7, 3.0, 3.5, 4.0, 4.5, 5.0mm; the stator 9 is also disc-shaped with a hole in the middle for the motor shaft 3 to pass through, i.e., the motor shaft 3 passes through the middle of the stator 9; the stator 9 and the housing 12 are fixedly connected, specifically by screws, pins, or interference fits; the rotor, stator 9, and motor shaft 3 are coaxially arranged; an elastic device is provided between the rotor and stator 9 to help the rotor return to its original position when the axial suction force weakens; preferably, the elastic device here is a return spring 6. A shim 5 is placed between the rotor and the elastic device to maintain the stability of the mechanical structure, distribute stress, and reduce vibration and noise. This self-cooling axial flux motor converts electrical energy into kinetic energy through the cooperation of the rotor and stator 9, and outputs the kinetic energy through the motor shaft 3. When the axial suction force increases or decreases, the elastic device provides flexible protection for the rotor, stator 9, and bearing 2, helping to utilize the axial suction force as a cooling power source.

[0038] The number of rotors can be one or more, and the number of multiple rotors can be 2, 3, 4, 5, 6...N, where N is a natural number greater than 1. Multiple rotors and multiple stators 9 are interspersed, meaning one rotor is placed between every two adjacent stators 9, or one stator 9 is placed between every two adjacent rotors. For example, one stator 9 and one rotor; one stator 9 between two rotors; one rotor between two stators 9, and so on. In a specific embodiment, the number of rotors is two, namely a first rotor 4 and a second rotor 11, with one stator 9 placed between the two rotors. The first rotor 4 and the second rotor 11 are located at both ends of the stator 9, i.e., a dual-rotor single-stator cooling scheme. The motor shaft 3 is stepped, used to install different... The rotors are positioned such that the first rotor 4 and the second rotor 11 extend along the axis of the motor shaft 3, respectively located on the first and second steps of the motor shaft 3. The radial radius of the first step is greater than that of the second step. In one specific embodiment, because the radial radius of the first rotor is greater than that of the second rotor, in order to better install and fix the second rotor, that is, the second rotor needs to be equipped with an elastic device for axial positioning of the second rotor on the motor shaft. The axial positioning of the first rotor is completed by the shoulder of the motor shaft, so the first rotor does not need the assistance of an elastic device to complete the axial positioning. An elastic device is provided on the outer side of the second rotor for fixing the second rotor and the motor shaft, which facilitates the assembly of the second rotor and the motor shaft 3. Preferably, the elastic device here is an elastic retaining ring 10.

[0039] Both the first rotor 4 and the second rotor 11 are located within the housing. The first rotor 4 is connected to the first step of the motor shaft 3 via a sliding key, and the second rotor 11 is connected to the second step of the motor shaft 3 via a sliding key. The positional structure of the rotors and stator 9 facilitates the formation of the working cooling structure and the axial suction drive mechanism, ensuring the normal operation of the motor, protecting the rotors and stator 9 themselves, reducing wear, and extending service life. This application continues the description with the example of the first rotor 4 and the second rotor 11 being located at both ends of the stator 9. Of course, there are other embodiments of the rotor and stator 9 positions:

[0040] In another specific embodiment, there are 3 rotors and 2 stators 9, and the order of their positions is as follows: first rotor, first stator, second rotor, second stator, and third rotor. In another specific embodiment, there are 2 rotors and 3 stators, and the order of their positions is as follows: first stator, first rotor, second stator, second rotor, and third stator.

[0041] like Figure 1 As shown, the rotor includes a rotor core and rotor permanent magnets (in Figure 1The first rotor permanent magnet 4b is located in the middle of the rotor core. The rotor permanent magnet is installed on the outer surface of the rotor core to provide a stable and uniform magnetic field for the rotor. It interacts with the rotating magnetic field generated by the stator coil winding 8 to drive the rotor to rotate.

[0042] The stator includes a stator core, a stator permanent magnet, and stator coil windings. The stator core, made of laminated silicon steel sheets with an insulating coating, is located in the center of the stator 9. It is disc-shaped or annular, with uniformly distributed slots on its inner or outer circumference. The stator core provides a low-resistivity path for the magnetic field generated by the stator permanent magnet and also provides mechanical support for the stator coil windings. In one specific embodiment, the stator core has an annular structure, with winding slots evenly distributed on the inner circumference surface of the stator core. The stator coil windings 8 are embedded into these winding slots according to certain rules and methods, such as single-layer windings or double-layer windings.

[0043] The stator core includes the stator yoke, made of a material with good magnetic permeability. The stator yoke is the part of the stator core that forms the magnetic circuit. The magnetic flux of the stator core forms a closed loop through the stator yoke. The stator yoke provides the extension and closed path of the magnetic circuit for the stator core, thus forming a complete stator magnetic circuit system, reducing leakage flux, improving magnetic field utilization, ensuring effective distribution and utilization of the magnetic field, and also providing mechanical support for the stator. The stator yoke is ring-shaped or nearly ring-shaped. The stator yoke provides a low-resistivity path for the magnetic flux generated by the stator coil winding 8, allowing the magnetic flux to pass effectively through the stator 9 and interact with the rotor to achieve energy conversion in the motor. For example, in large generators, the stator yoke can guide the strong magnetic flux generated by the stator coil winding 8 to interact with the rotor magnetic field, achieving efficient electrical energy generation. The stator yoke provides mechanical support and fixation for the stator coil winding 8 and other stator components, ensuring they maintain the correct position and relative relationship during motor operation, improving the structural stability of the motor. The thickness of the stator yoke in the prior art ranges from 3mm to 5mm in the radial direction, while the stator yoke of this application has a thickened portion in the radial direction away from the motor shaft axis. The thickness of the stator yoke with the thickened portion ranges from 8mm to 15mm. In other words, the stator yoke of this application has a thickened portion. The thickness of the stator yoke (with the thickened portion) of this application ranges from 8mm to 15mm. The thickened section of the rotor and the outer wall of the end of the stator yoke constitute a slit throttling valve. The stator yoke (with the thickened portion) of this application can improve the stability of the slit, ensure controllable coolant flow direction, improve mechanical strength, increase motor efficiency, reduce losses and heat generation, and facilitate the formation of a slit with the thickened section 16.

[0044] The stator permanent magnet is made of high-performance permanent magnet materials such as neodymium iron boron. It is mounted on the stator core using methods such as surface bonding and embedded mounting. In surface bonding, the stator permanent magnet is directly attached to the surface of the stator core; in embedded mounting, it is embedded in permanent magnet slots inside the stator core, allowing the magnetic field generated by the stator to form a closed magnetic circuit through the core. The stator permanent magnet generates a constant magnetic field, which interacts with the rotor magnetic field to produce electromagnetic torque, thus converting electrical energy into mechanical energy. In one specific embodiment, the stator permanent magnet is attached to the surface of the stator core.

[0045] The stator coil winding 8 is made of insulated wire and commonly comes in concentrated and distributed winding forms. When current flows through the stator coil winding, it generates a magnetic field, which interacts with the stator permanent magnet and the rotor magnetic field, driving the rotor to rotate. Simultaneously, it generates an induced electromotive force (EMF) during motor operation. The stator coil winding 8 is mounted in the winding slots of the stator core; specifically, it is embedded within these slots. The stator core provides support and fixation for the stator coil winding 8, ensuring its positional stability during motor operation. Furthermore, the magnetic permeability of the stator core helps the magnetic field generated by the stator coil winding 8 interact better with other magnetic fields. The interaction between the magnetic field generated by the energized stator coil winding 8 and the magnetic field of the stator permanent magnet is crucial for the motor to generate electromagnetic torque. This magnetic field interaction drives the rotor to rotate, realizing the motor's energy conversion function. Simultaneously, the induced EMF generated by the stator coil winding 8 is also related to the changes in the magnetic field of the stator permanent magnet.

[0046] like Figure 3-5As shown, the outer wall of the rotor is provided with a thickened section 16 in the radial direction away from the axis of the motor shaft, which is used to form a slit 17 with the end outer wall of the stator (specifically the stator yoke), thereby constituting a slit throttle valve. A first cavity 18 is formed between the rotor, stator 9, and housing 12. The first cavity 18 may contain coolant for cooling the rotor and stator 9. The coolant may be an organic liquid coolant, such as hydraulic oil, lubricating oil, glycerin, or ethanol. Preferably, the coolant is mineral oil or synthetic oil. In the first cavity 18, the gap between the slit between the thickened section 16 and the outer wall of the stator (specifically, the stator yoke) is very small, ranging from 5 to 5000 μm, forming a throttling channel. When the coolant passes through the slit, a pressure drop (i.e., pressure loss) occurs due to viscous resistance. According to Poiseuille's law (i.e., the relationship between pressure drop and flow rate), throttling is achieved, thus forming a slit throttling valve, thereby ensuring the flow direction of the coolant. Due to the viscosity of the coolant, a certain resistance is generated in the first cavity 18, causing the coolant to flow to the second cavity 19 while not all of it flowing back along the original path. It should be noted that the slit throttle valve is a type of throttle valve that controls fluid flow through the slit 17. When the coolant passes through the slit throttle valve orifice, the cross-sectional area of ​​the channel changes, thereby altering the volume of coolant flowing out and achieving a throttling effect. When the axial suction increases and the rotors (including the first rotor 4 and the second rotor 11) move closer to the stator 9, the volume of the first cavity 18 decreases, the cross-sectional area of ​​the slit throttle valve channel decreases, and the volume of coolant flowing out of the slit 17 decreases, achieving a throttling effect. When the axial suction decreases and the rotors (including the first rotor 4 and the second rotor 11) move away from the stator 9, the volume of the first cavity 18 increases, the cross-sectional area of ​​the slit throttle valve channel increases, and the volume of coolant flowing out of the slit 17 increases. Coolant preferentially flows along the path of least resistance. Without the throttling structure of the slit throttle valve, the resistance encountered by the coolant returning would be less than or equal to... Figure 4 The resistance encountered by the small arrow-shaped flow prevents most of the coolant from dissipating heat from the stator. The design of the first cavity 18 cleverly saves space, materials, reduces costs, and increases efficiency. The slit throttling valve formed by the thickened section 16 and the end outer wall of the stator yoke ensures the direction of coolant flow.

[0047] In one specific embodiment, heat dissipation fins are provided on the outer casing for heat dissipation, that is, heat from the coolant is dissipated to the air. Specifically, the heat dissipation fins are located on the outer wall of the housing 12 and / or the outer wall of the end cover 1, preferably on the outer wall of the end cover 1. To further accelerate heat dissipation, the self-cooling axial flux motor can also be equipped with a fan, which blows the heat from the heat dissipation fins and the housing to the air quickly, thereby ensuring the normal and efficient operation of the self-cooling axial flux motor. The fan can be located on the outer casing (either the housing 12 or the end cover 1) or on an external device. The heat generated by the stator and rotor in this application is transferred to the first cavity through the coolant, and then dissipated to the air through the outer casing and the heat dissipation fins. The heat dissipation fins and the fan further accelerate the heat dissipation speed of the self-cooling axial flux motor, ensuring its efficient operation. In other words, this application combines the advantages of both air cooling and liquid cooling in the prior art, and overcomes the disadvantages of low heat dissipation efficiency in the prior art which only has air cooling and no internal coolant flow, and the disadvantages of liquid cooling which only has liquid cooling, which requires an independent oil pump, has complex piping, high cost, large space occupation, and is prone to leakage.

[0048] A sealing ring 7 is provided on the outer side of the stator 9 to seal the stator 9 and prevent the coolant in the first cavity 18 from intruding. The sealing ring 7 is arranged circumferentially along the stator 9; the sealing ring 7 is located between the stator 9 and the housing 12 of the outer casing to stabilize the stator 9. The number of sealing rings 7 can be one or more, such as two, three, four, or five. The multiple sealing rings 7 are spaced apart along the axis of the stator 9. In a specific embodiment, the number of sealing rings 7 is two, and the two sealing rings 7 are evenly arranged along the axis of the stator 9, thereby preventing the intrusion of coolant from the first cavity 18 formed by the first rotor 4 and the second cavity 19 formed by the second rotor 11, respectively. The sealing ring 7 protects the stator 9 for safe use and extends the service life of the stator 9.

[0049] like Figure 3 , 4As shown, the stator 9 has a second cavity 19 inside. In the longitudinal sectional view, the second cavity 19 is inverted T-shaped and includes a first flow channel 21 and a second flow channel 22. The first flow channel 21 is parallel to the motor shaft 3 and its upper and lower ends are respectively connected to the first cavity 18. The second flow channel 22 is perpendicular to the first flow channel 21. One end of the second flow channel 22 is connected to the first flow channel 21, and the other end is connected to the valve core 14 of the one-way valve. In a specific embodiment, the position where the second flow channel 22 connects to the valve core 14 is located in the middle of the valve core 14. Preferably, the valve core 14 is symmetrically arranged with respect to the extension line of the second flow channel 22. The second cavity 19 is set inside the stator 9, which cleverly saves space and materials. The cooperation of the first cavity 18 and the second cavity 19 effectively solves the heat dissipation of the rotor and the stator 9, and the structure is simple, occupies little space, has low cost, and high efficiency. In use, the first flow channel 21 includes an upper port and a lower port. Under the action of axial suction, the coolant flows into the second cavity 19 from the upper port and the lower port respectively, and then converges in the middle of the first flow channel 21 and flows out into the first cavity along the second flow channel 22.

[0050] like Figure 2 , 3 As shown, the working cooling structure also includes a one-way valve, which is located on the outside of the stator 9 and is detachably connected to the housing 12 of the outer casing. The one-way valve ensures that the coolant cannot flow back, thus creating a circulation loop where most of the coolant flows in one direction. The one-way valve can also be used for adding and discharging coolant, as well as for regulating the coolant pressure and changing the coolant flow rate. The one-way valve includes a valve core 14, a valve spring 15, and an oil seal bolt 13. The valve spring 15 is located between the valve core 14 and the oil seal bolt 13. One end of the valve spring 15 is connected to the valve core 14, and the other end... The oil seal bolt 13 is connected to the housing 12 of the outer casing. It is used for the injection and discharge of coolant, and also for sealing the coolant. Loosening the oil seal bolt 13 allows for the injection or discharge of coolant, while tightening it seals the coolant. Adjusting the tightness of the oil seal bolt 13 also adjusts the pressure of the valve spring 15, thereby regulating the coolant pressure and changing its flow rate. The valve core 14 is connected to the second flow channel 22, allowing the valve spring 15 to open and close the passage from the first chamber to the second chamber via the second flow channel 22. Through contact between the coolant and the housing via the check valve, the coolant dissipates heat to the housing, reducing the rotor and stator temperatures and solving the heat dissipation problem. The structure of the first chamber 18, the second chamber 19, and the check valve forms a coolant circulation system, which also allows for the adjustment of the coolant flow rate, ensuring the heat dissipation needs of the rotor and stator 9 and the normal operation of the motor. In general, the pressure of the coolant has three effects: the first comes from the axial suction between the stator 9 and the rotor, the second comes from the resistance formed by the slit 17 between the stator 9 and the rotor, and the third comes from the pressure of the valve spring 15.

[0051] In use, when the direction and magnitude of the electromagnetic force change according to a certain pattern, the rotor performs periodic reciprocating motion along the sliding key. When the axial suction force increases, the rotor (including the first rotor 4 and the second rotor 11) moves towards the stator 9, compressing the elastic device, such as... Figure 4 In the direction indicated by the thick arrow, the coolant moves from the first flow channel 21 to the second flow channel 22, compressing the volume of the compression valve spring 15 and the second chamber 19, as shown. Figure 4 As indicated by the thin arrow, the coolant flows from the second flow channel 22 of the stator 9 along both sides of the valve core 14 to the first cavity formed by the first rotor 4 and the first cavity formed by the second rotor 11, respectively. The volume of the first cavity 18 is compressed, pushing the coolant in the first cavity formed by the first rotor 4 and the first cavity formed by the second rotor 11 towards the second cavity of the stator 9. When the axial suction weakens, the elastic device extends, and the rotor moves away from the stator 9, the volume of the second cavity 19 increases, the valve spring 15 extends, the volume of the first cavity 18 increases, the flow of coolant gradually decreases, and the one-way valve gradually closes. The pressure of the valve spring 15 can also be changed by adjusting the tightness of the oil seal bolt 13, thereby adjusting the coolant pressure and changing the coolant flow rate. The magnitude of the axial suction is mainly determined by the magnitude of the current (specifically, the square of the current), and the direction of the axial suction depends on the direction of the current and the polarity of the rotor permanent magnet. It should be noted that when the elastic device (reset spring) is placed between the rotor and the stator, if the axial flux motor is an axial flux permanent magnet synchronous motor, the axial attraction mainly manifests as attracting the rotor and stator closer together; if it is a switched reluctance motor, the axial attraction generally manifests as moving the rotor away from the stator, and in this case, the reset spring should also be placed on the outside of the rotor.

[0052] like Figure 4 As shown, it should be noted that the thin arrow points to the direction of coolant flow when the self-cooling axial flux motor is working, and the thick arrow points to the direction of rotor movement when the self-cooling axial flux motor is working. In use, when the axial suction force increases, the rotor moves towards the stator 9 along the axis of the motor shaft 3, compressing the elastic device and also compressing the first flow channel 21 of the second cavity 19, promoting the coolant in the first flow channel 21 to move towards the second flow channel 22. This causes the coolant in the crossbar to flow through the one-way valve to the first cavity 18 formed by the first rotor 4 and the first cavity 18 formed by the second rotor 11, thereby causing the coolant in the first cavity 18 formed by the first rotor 4 and the first cavity 18 formed by the second rotor 11 to flow into the first flow channel 21 of the second cavity 19, forming a circulating flow. When the axial suction force decreases, the elastic device gradually extends, and when the rotor moves away from the stator 9, the valve spring 15 gradually extends, and the one-way valve gradually closes.

[0053] During operation, the rotor and stator 9 of the self-cooling axial flux motor generate heat, with the temperature in the rotor and stator 9 area being higher than other areas. Simultaneously, the axial attraction between the stator 9 and rotor exacerbates wear on the motor and bearing 2. Compared to existing technologies, the self-cooling axial flux motor, based on the working principle of a hydraulic pump, incorporates a thickened section 16 on the outer wall of the rotor, a thickened stator yoke, and a working cooling structure (including a first cavity 18 and a second cavity 19) between the rotor and stator that functions similarly to a hydraulic pump. Coolant is placed in this working cooling structure, and an elastic device is installed between the stator 9 and rotor. A sliding key is designed on the motor shaft 3 to allow the rotor to move along the axis. The axial attraction generated during motor operation periodically draws the rotor into the oil chamber, and the coolant circulates through the first cavity 18 and the second cavity 19 to dissipate heat. This allows heat to diffuse to the outside, reducing the temperature in the rotor and stator 9 area, improving heat dissipation uniformity, and reducing localized overheating.

[0054] The self-cooling axial flux motor has a second cavity 19 inside the stator 9, a sealing ring 7 on the outside of the stator 9, and a first cavity 18 inside the stator 9 and the rotor outer casing 12 to form a coolant circulation loop. A one-way valve is set to control the flow of coolant. The axial suction force is used to ensure good heat dissipation of the rotor and stator 9. The structure is simple, occupies little space, has low cost and high efficiency.

[0055] This application provides a self-cooling axial flux motor driven by axial suction, which eliminates the need for an external cooling oil pump, reducing size and cost; converts axial suction into heat dissipation power, extending the life of bearing 2; integrates the coolant and motor into a single design, reducing the risk of leakage; and can dynamically match heat dissipation requirements by adjusting the current and electromagnetic control of the axial suction strength.

[0056] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features of the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0057] For those skilled in the art, this invention can be implemented through other embodiments that do not depart from its spirit or essential characteristics. It is obvious that this invention is not limited to the details of the above exemplary embodiments, and that it can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, all embodiments are merely illustrative and not exhaustive, and should be considered exemplary and non-limiting. The scope of this invention is defined by the appended claims rather than the foregoing description, and therefore all changes falling within the meaning and scope of equivalents of the claims are intended to be included within this invention. No reference numerals in the claims should be construed as limiting the scope of the claims. All changes within the scope of this invention or its equivalents are included in this invention.

Claims

1. A self-heating axial flux motor based on axial attraction drive, characterized in that, include: Housing, motor shaft, working cooling structure, and axial suction drive mechanism; The motor shaft, the working cooling structure, and the axial suction drive mechanism are disposed in the housing, wherein the housing and the motor shaft are connected by bearings; The axial suction drive mechanism includes a stator and a rotor; the motor shaft passes through the rotor, and the rotor and the motor shaft are connected by a sliding key; the motor shaft passes through the stator; the stator and the housing are fixedly connected; the rotor can move along the axial direction of the motor shaft via a sliding key. The working cooling structure includes a first cavity and a second cavity; The rotor, the stator, and the housing form the first cavity; the stator has a second cavity inside; the first cavity and the second cavity are connected, and both the first cavity and the second cavity are filled with coolant; The outer wall of the rotor is provided with a thickened section in the radial direction away from the axis of the motor shaft; In the first cavity, the thickened section of the rotor and the outer wall of the stator end form a slit throttling valve to achieve unidirectional flow of coolant.

2. The self-heating axial flux motor according to claim 1, characterized in that, A stator core is provided in the middle of the stator, and the stator core includes a stator yoke, the thickness of which ranges from 8 to 15 mm. The thickened section and the outer wall of the stator yoke form a slit throttling valve.

3. The self-heating axial flux motor according to claim 1, characterized in that, The rotor's range of movement along the axial direction of the motor shaft does not exceed 3mm; An elastic device is provided between the rotor and the stator for the rotor to be reset.

4. The self-heating axial flux motor according to claim 1, characterized in that, One rotor is provided between every two adjacent stators, or one stator is provided between every two adjacent rotors.

5. The self-heating axial flux motor according to claim 1, characterized in that, The distance between the thickened section and the outer wall of the stator end ranges from 5 to 5000 μm.

6. The self-heating axial flux motor according to claim 1, characterized in that, A fan is provided on the housing or external device for heat dissipation.

7. The self-heating axial flux motor according to claim 1, characterized in that, A sealing ring is fitted on the outer side of the stator, and the sealing ring is arranged along the circumference of the stator.

8. The self-heating axial flux motor according to claim 1, characterized in that, The second cavity includes a first flow channel and a second flow channel. The first flow channel is parallel to the motor shaft and communicates with the first cavity; The second flow channel is perpendicular to the first flow channel.

9. The self-heating axial flux motor according to claim 8, characterized in that, The working cooling structure also includes a one-way valve, which is located on the outside of the stator. One end of the second flow channel is connected to the first flow channel, and the other end is connected to the one-way valve.

10. The self-heating axial flux motor according to claim 9, characterized in that, The one-way valve includes a valve core, a valve spring, and an oil seal bolt. The valve core is connected to the second flow channel and is used to switch the passage from the first cavity to the second flow channel of the second cavity using the valve spring; One end of the valve spring is connected to the valve core, and the other end is connected to the oil seal bolt; The oil seal bolt is threadedly connected to the outer casing and is used for the injection and discharge of coolant.

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