Stator assembly, wheel hub motor and electric vehicle

Abstract

This invention discloses a stator assembly, a hub motor, and an electric vehicle. The stator assembly includes a stator core, a stator bracket, a support bracket, and a Hall plate. The stator core has a closed yoke, and multiple teeth are arranged on the outer periphery of the yoke. The teeth are connected to windings. The stator bracket is fixedly connected to the stator core and is located inside the yoke. The support bracket is connected to the stator bracket and has at least one Hall plate mounting bracket. The Hall plate is connected to the Hall plate mounting bracket and has at least one Hall sensor connected to it. Along the radial direction of the stator core, the Hall sensor is located outside the windings. The support bracket of the stator assembly mounts the Hall plate through the Hall plate mounting bracket. The Hall sensor is connected to the Hall plate and is located outside the windings, corresponding to the permanent magnet of the rotor assembly, to sense the magnetic field. This eliminates the need to create sensor mounting slots in the stator core, preventing interference with the electromagnetic performance of the stator assembly and improving the performance of the hub motor.

Description

Technical Field

[0001] This invention relates to the field of motor technology, and in particular to a stator assembly, a hub motor, and an electric vehicle. Background Technology

[0002] In related technologies, Hall sensors are incorporated into hub motors. These sensors are typically installed in the stator core, requiring a mounting slot to be created within the stator core. The Hall sensor is then fixed in the slot using cold pressing or adhesive bonding. The Hall sensor senses the magnetic field of the permanent magnet in the rotor assembly in the radial direction. The sensor mounting slot affects motor performance to some extent, and the Hall sensor installation process is complex and requires improvement. Summary of the Invention

[0003] This invention aims to at least solve one of the technical problems existing in the prior art. To this end, this invention proposes a stator assembly with a simple installation process for the Hall sensor, effectively improving the reliability of the Hall sensor.

[0004] The present invention also proposes a hub motor having the above-mentioned stator assembly.

[0005] The present invention also proposes an electric vehicle having the above-mentioned hub motor.

[0006] According to a first aspect of the present invention, a stator assembly includes a stator core, a stator bracket, a support bracket, and a Hall plate. The stator core has a closed yoke, and a plurality of teeth are provided on the outer periphery of the yoke. The teeth are connected to windings. The stator bracket is fixedly connected to the stator core and is located inside the yoke. The support bracket is connected to the stator bracket and is provided with at least one Hall plate mounting bracket. The Hall plate is connected to the Hall plate mounting bracket and is connected to at least one Hall sensor. Along the radial direction of the stator core, the Hall sensor is located outside the windings.

[0007] According to the first aspect of the present invention, the stator assembly has at least the following advantages: the stator bracket of the stator assembly is connected to a support bracket, the support bracket mounts a Hall plate via a Hall plate mounting bracket, a Hall sensor is connected to the Hall plate, the Hall sensor is located outside the winding, corresponding to the permanent magnet of the rotor assembly, and is capable of sensing the axial end magnetic field of the rotor permanent magnet; the stator assembly uses a Hall plate to mount the Hall sensor, eliminating the need to open a sensor mounting slot in the stator core, preventing any impact on the electromagnetic performance of the stator assembly, and thus improving the performance of the hub motor.

[0008] According to some embodiments of the first aspect of the present invention, the support bracket is provided with a plurality of Hall plate mounting brackets, the plurality of Hall plate mounting brackets being distributed at circumferential intervals along the support bracket.

[0009] According to some embodiments of the first aspect of the present invention, the support bracket is provided with three Hall plate mounting brackets, the Hall plates being arc-shaped and connected to the three Hall plate mounting brackets.

[0010] According to some embodiments of the first aspect of the present invention, the Hall plate mounting bracket is provided with a first connector, and the Hall plate is provided with mounting holes that mate with the first connector.

[0011] According to some embodiments of the first aspect of the present invention, the first connector includes a plurality of columns, the plurality of columns being circumferentially distributed, and a stop block being provided at the end of each column, the stop block abutting against the Hall plate.

[0012] According to some embodiments of the first aspect of the present invention, the Hall plate mounting bracket is provided with ribs, the ribs and the first connector are arranged on two opposite sides of the Hall plate mounting bracket, and the ribs are connected to the support bracket.

[0013] According to some embodiments of the first aspect of the present invention, the support bracket is provided with a plurality of second connectors, the plurality of second connectors being distributed circumferentially along the support bracket, and the second connectors being connected to the stator support.

[0014] According to some embodiments of the first aspect of the present invention, the support bracket is provided with a plurality of cross-slot connecting lines, which are electrically connected to the winding.

[0015] The hub motor according to a second aspect of the present invention includes the stator assembly of the first aspect of the present invention.

[0016] According to some embodiments of the second aspect of the present invention, a hub motor includes a central shaft, a stator assembly fixedly connected to the central shaft, a rotor assembly supported on the central shaft by bearings, the rotor assembly having a permanent magnet, and a Hall sensor corresponding to the permanent magnet along the radial direction of the central shaft.

[0017] According to some embodiments of the second aspect of the present invention, the distance between the Hall sensor and the permanent magnet along the axial direction of the central axis is L, satisfying 1mm≤L≤4mm.

[0018] An electric vehicle according to a third aspect of the present invention includes a hub motor according to a second aspect of the present invention.

[0019] Additional aspects and advantages of the present invention will be set forth in part in the description which follows and, in part, will be obvious from the description which follows, or may be learned by practice of the present invention. Attached Figure Description

[0020] Additional aspects and advantages of the invention will become apparent and readily understood in conjunction with the following description of the embodiments in conjunction with the accompanying drawings, wherein:

[0021] Figure 1 This is a cross-sectional view of a hub motor according to a second aspect embodiment of the present invention;

[0022] Figure 2 This is a schematic diagram of the structure of the stator assembly according to a first aspect embodiment of the present invention. Figure 1 ;

[0023] Figure 3 This is a schematic diagram of the structure of the stator assembly according to a first aspect embodiment of the present invention. Figure 2 ;

[0024] Figure 4 This is a schematic diagram of the structure of the support bracket and Hall plate in the first aspect embodiment of the present invention. Figure 1 ;

[0025] Figure 5 This is a schematic diagram of the structure of the support bracket and Hall plate in the first aspect embodiment of the present invention. Figure 2 ;

[0026] Figure 6 This is a schematic diagram of the support bracket structure in the first aspect embodiment of the present invention;

[0027] Figure 7 This is a schematic diagram of the support bracket structure with the cross-slot connecting line removed in the first aspect embodiment of the present invention. Figure 1 ;

[0028] Figure 8 This is a schematic diagram of the support bracket structure with the cross-slot connecting line removed in the first aspect embodiment of the present invention. Figure 2 ;

[0029] Figure 9 for Figure 7 Enlarged view of point A in the image;

[0030] Figure 10 This is a schematic diagram of the rotor assembly in a second aspect embodiment of the present invention. Figure 1 ;

[0031] Figure 11 This is a schematic diagram of the rotor assembly in a second aspect embodiment of the present invention. Figure 2 ;

[0032] Figure 12 This is an exploded view of the rotor assembly in a second aspect embodiment of the present invention.

[0033] The attached icons are numbered as follows:

[0034] Central shaft 100, bearing 110;

[0035] Housing assembly 200, sealing cavity 201, main housing 210, second retaining ring 211, auxiliary housing 220, wheel rim 230;

[0036] Stator assembly 300, winding 310, tooth 321, yoke 322, stator bracket 330, bushing 331, support bracket 340, Hall plate mounting bracket 341, rib 3411, first connector 342, column 3421, stop block 3422, second connector 343, cross-slot connecting line 344, Hall plate 350, Hall sensor 351;

[0037] Rotor assembly 400, rotor plastic-coated part 410, rotor plastic-coated part 410, first retaining ring 411, heat dissipation fan blade 412, inner sleeve 413, flow guide hole 414, bearing seat 420, magnetic yoke 430, permanent magnet 440;

[0038] Gear assembly 500, sun gear 510, planet gear 520, planet carrier 530, external gear ring 540. Detailed Implementation

[0039] Embodiments of the present invention are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0040] In the description of this invention, it should be understood that the orientation descriptions, such as up, down, front, back, left, right, etc., are based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention 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. Therefore, they should not be construed as limiting this invention.

[0041] In the description of this invention, the use of "first" and "second" is for the purpose of distinguishing technical features only, and should not be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated or the order of the technical features indicated.

[0042] In the description of this invention, unless otherwise explicitly defined, terms such as "set up," "install," and "connect" should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this invention in conjunction with the specific content of the technical solution.

[0043] In related technologies, electric vehicles use in-wheel motors as the power component. The outer rotor of the in-wheel motor and the wheel rim are integrated into a single structure. The design of in-wheel motors aims to integrate the power system, transmission system, and braking system into a single unit. In-wheel motors incorporate Hall effect sensors, which sense the magnetic field of the permanent magnets in the rotor assembly in the radial direction. Hall effect sensors are typically mounted on the stator core, requiring a mounting slot to be created within the stator core. The sensor is then fixed in the slot using cold pressing or adhesive bonding. However, the mounting slot design can negatively impact motor performance, and the Hall effect sensor installation process is complex and requires improvement. The Hall effect sensor and the Hall plate are connected via pins or hard wires. After prolonged operation of the in-wheel motor, these pins or hard wires are prone to breakage, which is one of the main failure problems of in-wheel motors in electric vehicles, affecting the reliability of the electric vehicle.

[0044] like Figure 1 As shown, an embodiment of the second aspect of the present invention provides a hub motor for an electric vehicle. The hub motor includes a central shaft 100 and a housing assembly 200, a stator assembly 300, a rotor assembly 400, and a gear assembly 500 connected to the central shaft 100. The central shaft 100 is connected to the frame of the electric vehicle and serves as a mounting base. The housing assembly 200 includes a main housing 210, a secondary housing 220, and a rim 230. The main housing 210 and the secondary housing 220 are respectively disposed at both ends of the rim 230 and are fixedly connected to both ends of the rim 230 by screws. Three bearings 110 are installed on the central shaft 100. The main housing 210, the secondary housing 220, and the rotor assembly 400 are each connected to one bearing 110 and can all rotate relative to the central shaft 100.

[0045] Reference Figure 2 and Figure 3 The stator assembly 300 includes a winding 310 and a stator core. The stator core includes a yoke 322 and multiple toothed portions 321 without teeth. The winding 310 is connected to the toothed portions 321. The stator core has a certain thickness and forms a closed yoke 322. The multiple toothed portions 321 are evenly distributed circumferentially along the yoke 322. The toothed portions 321 are straight teeth to facilitate the insertion of the winding 310.

[0046] Stator cores are typically made from silicon steel sheets. These sheets are then processed into wound stator cores. To improve the utilization rate of the silicon steel sheets, a pre-designed splicing and cutting method is necessary. If the stator core teeth 321 have toothed shoes, the splicing and cutting method must be designed according to the toothed shoes when cutting the stator core. However, regardless of optimization, the material utilization rate of the silicon steel sheets can only reach a maximum of 70% with toothed shoes, making further improvement difficult. This embodiment of the invention uses a toothed section 321 without toothed shoes, optimizing the splicing and cutting method, thereby improving the material utilization rate of the silicon steel sheets.

[0047] Understandably, the toothed section 321 is designed with straight teeth, eliminating the need for the winding 310 to be wound on the toothed section 321. Winding can be completed externally using tooling, providing ample operating space and effectively improving the slot fill factor. Furthermore, the winding 310 uses non-circular cross-section aluminum wire, such as rectangular, square, or oval cross-sections, while the toothed section 321 employs a straight toothed structure, for example, a square cross-section. The aluminum wire of the winding 310 matches the shape of the toothed section 321, tightly adhering to the outer wall of the toothed section 321, resulting in a more compact arrangement of the aluminum wires. This improves the slot fill factor of the stator assembly 300, increasing the power density and efficiency of the hub motor while maintaining the same volume. Integrating hub motors into electric vehicles helps improve their range.

[0048] Reference Figure 2 and Figure 3 An embodiment of the first aspect of the present invention provides a stator assembly 300 for a hub motor. The stator core of the stator assembly 300 is connected to a stator bracket 330, which is installed in the inner hole of the yoke 322. The stator bracket 330 is fixed integrally with the stator core. A bushing 331 is provided in the middle of the stator bracket 330 and is fixed to the central shaft 100 to position the stator assembly 300. A support bracket 340 is installed on the stator bracket 330, and at least one Hall plate mounting bracket 341 is provided around the periphery of the support bracket 340. The Hall plate mounting bracket 341 is used to install a Hall plate 350, and at least one Hall sensor 351 is provided on the Hall plate 350. In the radial direction of the central shaft 100, the Hall sensor 351 corresponds to the position of the permanent magnet 440 of the rotor assembly 400. Figure 1 As shown, the permanent magnet 440 is located on the outside of the winding 310, and the Hall sensor 351 is also located on the outside of the winding 310. The Hall sensor 351 is used to sense the magnetic field at the end of the permanent magnet 440 to determine the position of the permanent magnet 440, which helps to accurately control the operation of the hub motor.

[0049] The stator assembly 300 has a support bracket 340, which mounts a Hall plate 350 via a Hall plate mounting bracket 341. The Hall sensor 351 is mounted on the Hall plate 350. The fixed installation of the Hall sensor 351 is simpler, easier to operate, and improves assembly efficiency. The stator assembly 300 uses the Hall plate 350 to mount the Hall sensor 351, eliminating the need to open a sensor mounting slot in the stator core, avoiding affecting the electromagnetic performance of the stator assembly 300, and helping to improve the performance of the hub motor.

[0050] It is understandable that the Hall plate 350 has certain external dimensions. In order to stably support the Hall plate 350, the support bracket 340 is provided with at least two Hall plate mounting brackets 341. If two Hall plate mounting brackets 341 are used, the two Hall plate mounting brackets 341 are connected to both ends of the Hall plate 350 to stably support the Hall plate 350 and prevent the Hall plate 350 from shifting or deforming.

[0051] Reference Figure 5 Understandably, considering that the rotor assembly 400 is a rotating circular component, the Hall plate 350 is equipped with three Hall sensors 351. These three Hall sensors 351 should be arranged in an arc shape to sense the magnetic field of the rotating permanent magnet 440. Correspondingly, the Hall plate 350 is an arc-shaped plate. Each phase of the stator assembly 300 corresponds to one Hall sensor 351, which facilitates driving the hub motor and increases its starting torque. Three Hall plate mounting brackets 341 are provided on the support bracket 340, with one bracket at each end and one in the middle of the Hall plate 350. These three brackets are also arranged in an arc shape, corresponding to the shape of the Hall plate 350.

[0052] Understandably, the Hall sensor 351 is connected to the Hall plate 350 using a surface mount structure, replacing pin or hard wire connections. This eliminates the problem of failure caused by broken pins or hard wires, greatly improving reliability and service life.

[0053] Reference Figures 4 to 7 It is understandable that the Hall plate mounting bracket 341 is provided with a first connector 342, which is used to fix the Hall plate 350. The Hall plate 350 is provided with mounting holes, and the first connector 342 cooperates with the mounting holes to fix the Hall plate mounting bracket 341 and the Hall plate 350.

[0054] Reference Figure 9 It is understood that the first connector 342 consists of four columns 3421, which are evenly distributed circumferentially to form a columnar body. This columnar body can pass through the mounting hole. A radially protruding stop 3422 is provided at the end of each column 3421. The stop 3422 of the four columns 3421 forms a retaining ring. After assembly, the stop 3422 and the Hall plate mounting bracket 341 cooperate to clamp the Hall plate 350, thereby achieving fixation. The stop 3422 prevents the first connector 342 from coming out of the mounting hole, improving stability during use. To facilitate assembly, a guide slope is provided on the stop 3422. During assembly, the edge of the mounting hole abuts against the guide slope, pressing down the Hall plate 350 and pushing the column 3421 to deform, automatically inserting it—simple and quick.

[0055] It is understandable that the cross-sections of the four columns 3421 can be fan-shaped, forming a columnar body, or they can be other shaped cross-sections, forming a columnar body. The number of columns 3421 can also be two, three, or more, which can still satisfy the requirement of fixing the Hall plate 350.

[0056] Understandably, the first connector 342 can also be made of screws, pins, rivets, etc., which can also be used with the mounting holes to fix the Hall plate 350 and meet the structural stability requirements.

[0057] Reference Figure 7 and Figure 8 The side of the Hall plate mounting bracket 341 with the first connecting member 342 is defined as the front, and the opposite side is the back. A rib 3411 is provided on the back, extending transversely along the length of the Hall plate mounting bracket 341. Considering that the support bracket 340 is an injection molded part, the Hall plate mounting bracket 341 and the rib 3411 are integrally injection molded, with the rib 3411 extending to the support bracket 340. The rib 3411 enhances the structural strength and rigidity of the Hall plate mounting bracket 341, which is beneficial for the stable support of the Hall plate 350.

[0058] Reference Figure 3 , Figure 5 and Figure 8 It is understandable that the support bracket 340 is also provided with multiple second connectors 343. The second connectors 343 are used to connect the stator bracket 330. Considering that the stator bracket 330 is circular, the multiple second connectors 343 are arranged in a ring along the circumference of the support bracket 340. Among them, the preferred solution is to use three circumferentially distributed second connectors 343.

[0059] It is understandable that the second connector 343 and the first connector 342 can adopt the same structure. For example, the second connector 343 is also composed of four columns 3421. The four columns 3421 are evenly distributed around the periphery and form a column shape. The four columns 3421 can pass through the through holes on the stator support 330 (not shown in the figure). A radially protruding stop block 3422 is provided at the end of the column 3421. The stop blocks 3422 of the four columns 3421 form a retaining ring. After assembly, the stop block 3422 and the support bracket 340 cooperate to clamp the stator support 330, thereby achieving fixation.

[0060] Of course, the second connector 343 can also be made of screws, pins, rivets, etc., which can also achieve the function of fixing the stator bracket 330 and meet the structural stability requirements.

[0061] Reference Figure 2 and Figure 4Understandably, the support bracket 340 is provided with multiple slot-connecting wires 344, which are electrically connected to the terminals of the winding 310. Multiple slot-connecting wires 344 are used to connect multiple windings 310 in series. The terminals of the slot-connecting wires 344 and the windings 310 can be fixed by welding. The slot-connecting wires 344 are located on the side away from the windings 310 for easy welding.

[0062] Reference Figure 1 The gear assembly 500 includes a sun gear 510, three planet gears 520, a planet carrier 530, and an external gear ring 540. The sun gear 510 is fixedly connected to the rotor assembly 400, the planet carrier 530 is fixedly connected to the central shaft 100, the three planet gears 520 are rotatably connected to the planet carrier 530, and the external gear ring 540 is fixedly connected to the main housing 210. The planet gears 520 mesh with both the sun gear 510 and the external gear ring 540. The rotor assembly 400 drives the sun gear 510 to rotate, the sun gear 510 drives the three planet gears 520 to rotate, and the three planet gears 520 then drive the external gear ring 540 and the main housing 210 to rotate. The main housing 210 drives the rim 230 to rotate. The rim 230 is the wheel of the electric vehicle, so the hub motor directly drives the wheel to rotate, thus enabling the electric vehicle to move. In addition, the planetary gear 520 is a double gear, which realizes two-stage transmission reduction, reduces the speed of the rim 230, and increases the output torque of the hub motor, which is beneficial to the acceleration of electric vehicles.

[0063] It is understandable that the gear assembly 500 is located between the rotor assembly 400 and the main housing 210. Therefore, the rotor assembly 400 and the main housing 210 cooperate to form a grease sealing cavity 201. The gear assembly 500 is located in the grease sealing cavity 201. The grease sealing cavity 201 serves two purposes: firstly, to accommodate the gear assembly 500 and prevent it from being exposed; and secondly, to contain grease so that the surfaces of the sun gear 510, the three planet gears 520, and the external gear ring 540 can be coated with grease, providing sufficient lubrication and reducing wear.

[0064] Understandably, considering that during the high-speed rotation of the sun gear 510 and the three planetary gears 520, the centrifugal force will cause the grease to be thrown off, leading to insufficient lubrication of the sun gear 510 and the three planetary gears 520, a first retaining ring 411 is provided on the rotor assembly 400, and a second retaining ring 211 is provided on the main housing 210. The first retaining ring 411 faces the main housing 210, and the second retaining ring 211 faces the rotor assembly 400. The first retaining ring 411 and the second retaining ring 211 form the sidewall of the grease sealing cavity 201, which prevents the grease from leaking out. In the axial direction of the central shaft 100, the first retaining ring 411 and the second retaining ring 211 are staggered, which can block the grease that is thrown off and make the grease remain in the grease sealing cavity 201, ensuring that the gear assembly 500 has sufficient lubrication. In the radial direction of the central shaft 100, the first retaining ring 411 and the second retaining ring 211 are close to each other but do not contact each other, so as not to affect the independent rotation of the rotor assembly 400 and the main housing 210. When the hub motor is running, the stator assembly of the hub motor drives the rotor assembly 400 to rotate through electromagnetic force. The rotor assembly 400 drives the housing assembly 200 to rotate through the gear assembly 500. The housing assembly 200 drives the wheels of the electric vehicle to rotate through the wheel rim 230, thus realizing the movement of the electric vehicle. The gear assembly 500 is located in the grease-sealing cavity 201 between the rotor assembly 400 and the main housing 210. The grease-sealing cavity 201 stores grease, which is coated on the surface of the gear assembly 500 to provide lubrication. The first retaining ring 411 of the rotor assembly 400 and the second retaining ring 211 of the main housing 210 are staggered in the axial direction to form a blocking structure, which can prevent the grease from being thrown out of the grease-sealing cavity 201, so that the grease remains in the grease-sealing cavity 201 to lubricate the gear assembly 500, improve the lubrication effect, avoid reliability problems such as wear and failure of the gear assembly 500 due to insufficient lubrication, improve the operational reliability of the hub motor, and improve the usage reliability of the electric vehicle.

[0065] It is understandable that the first retaining ring 411 and the second retaining ring 211 can also be non-intersecting in the axial direction of the central shaft 100, and the two can be arranged flush, that is, the end face of the first retaining ring 411 and the end face of the second retaining ring 211 are located on the same plane, which can also prevent the grease that is thrown off, so that the grease remains in the grease sealing cavity 201 and ensures that the gear assembly 500 has sufficient lubrication.

[0066] Reference Figure 1 Understandably, in the radial direction of the central shaft 100, the first retaining ring 411 is located outside the second retaining ring 211, and the second retaining ring 211 is closer to the central shaft 100. After the grease is thrown off, it first contacts the second retaining ring 211, and then contacts the first retaining ring 411. Moreover, the first retaining ring 411 and the second retaining ring 211 are staggered, which can restrict the thrown-off grease and keep the grease in the grease sealing cavity 201.

[0067] Reference Figures 10 to 12 It is understandable that the main component of the rotor assembly 400 is the rotor plastic-coated part 410. The rotor plastic-coated part 410 integrally wraps the magnetic yoke 430 and the permanent magnet 440 during the injection molding process. Furthermore, the bearing housing 420 is also integrally molded with the rotor plastic-coated part 410. The bearing housing 420 is located at the center of the rotor plastic-coated part 410, and its inner wall forms a bearing chamber to accommodate the bearing 110. To improve the stability of the connection, the outer wall of the bearing housing 420 has multiple circumferentially distributed bosses. After injection molding, these bosses are embedded in the rotor plastic-coated part 410, improving structural strength and facilitating torque transmission. Considering that the rotor plastic-coated part 410 is an injection-molded part, the first retaining ring 411 is placed on the rotor plastic-coated part 410 for ease of manufacturing and cost reduction. The rotor assembly 400 adopts an integrated structure. The magnetic yoke 430 and permanent magnet 440 are fixed by wrapping them with the rotor plastic-coated part 410, which prevents the permanent magnet 440 from falling off, improves the reliability of the rotor assembly 400, and helps to extend the service life of the hub motor.

[0068] Reference Figure 1 and Figure 6 It is understood that the rotor plastic-coated part 410 is provided with multiple heat dissipation fan blades 412, which are evenly distributed along the circumference of the rotor plastic-coated part 410. The rotor plastic-coated part 410 is provided with an inner sleeve 413, and the bearing housing 420 is connected to the inner wall of the inner sleeve 413. The heat dissipation fan blades 412 extend radially from the outer wall of the inner sleeve 413. Inside the hub motor, the heat dissipation fan blades 412 face the stator assembly 300, and the outer edge of the heat dissipation fan blades 412 is relatively low to avoid the windings 310 of the stator assembly 300. When the rotor assembly 400 rotates at high speed, the multiple heat dissipation fan blades 412 drive the airflow, thereby carrying away the heat generated by the windings 310, helping to cool down, and preventing over-temperature shutdown.

[0069] Reference Figures 6 to 8 It is understandable that the rotor plastic-coated part 410 is also provided with multiple guide holes 414. These guide holes 414 are evenly distributed along the circumference of the rotor plastic-coated part 410, and each guide hole 414 is arranged between the extension lines of two adjacent heat dissipation fan blades 412. For example, the guide holes 414 and heat dissipation fan blades 412 can correspond one-to-one, or the number of guide holes 414 can be half that of the heat dissipation fan blades 412. Figure 1As shown, when the rotor assembly 400 rotates at high speed, multiple cooling fan blades 412 drive the airflow. The guide hole 414 serves as a channel for airflow, connecting both sides of the rotor plastic-coated part 410. The airflow flows to the inner cavity of the housing assembly 200. The main housing 210 and the secondary housing 220 of the housing assembly 200 are metal parts, such as aluminum alloy parts, which have greater structural strength and excellent heat transfer performance. The airflow contacts the main housing 210 and the secondary housing 220, and dissipates heat to the external space through the main housing 210 and the secondary housing 220.

[0070] The rotor assembly 400 rotates at high speed, and the cooling fan 412 and guide holes 414 form an airflow circulation loop inside the hub motor, improving the air convection capacity inside the hub motor and effectively removing the heat generated by the winding 310. This enhances the heat dissipation performance of the hub motor, reduces its temperature rise, and ensures stable output efficiency, meeting the load-bearing operation requirements. Furthermore, the cooling fan 412 also acts as a reinforcing rib, improving the overall structural strength and rigidity of the rotor assembly 400 and enhancing its reliability.

[0071] Reference Figure 11 It is understandable that the first retaining ring 411 is integrally formed on the rotor plastic-coated part 410, and multiple guide holes 414 are arranged on the outer side of the first retaining ring 411. The airflow flowing through the guide holes 414 will not enter the grease sealing cavity 201, thus avoiding the airflow affecting the lubricating grease. Moreover, the guide holes 414 are located on the outer edge of the rotor plastic-coated part 410, allowing the airflow to flow quickly to the contact main housing 210, which is beneficial for heat dissipation.

[0072] Reference Figure 1 It is understandable that, in the radial direction of the central shaft 100, the distance between the winding 310 and the central shaft 100 is basically equal to the distance between the guide hole 414 and the central shaft 100. The two are in corresponding positions, which allows the heat dissipated by the winding 310 to be quickly carried away by the airflow passing through the guide hole 414, which helps to improve the heat dissipation effect of the winding 310.

[0073] Reference Figure 1It is understandable that, radially, the distance between the permanent magnet 440 and the central axis 100 is approximately equal to the distance between the Hall sensor 351 and the central axis 100. The Hall sensor 351 and the permanent magnet 440 are positioned correspondingly. When the rotor assembly 400 rotates, the Hall sensor 351 is located outside the axial end of the permanent magnet 440. The Hall sensor 351 is a magnetic field sensor capable of sensing the magnetic field at the end of the permanent magnet 440. This corresponding position enhances reliability. The Hall sensor 351 senses the magnetic field at the end of the permanent magnet 440, detecting the position of the permanent magnet 440's magnetic poles relative to the stator winding 300. The sensing information from the Hall sensor 351 can be input to the controller. By changing the current direction of the stator winding 310 at an appropriate time, the commutation of the hub motor can be completed, generating the required torque. Furthermore, the speed of the hub motor can also be controlled using the sensing information from the Hall sensor 351.

[0074] Understandably, the distance between the Hall sensor 351 and the permanent magnet 440 is defined as L, with a setting of 1mm ≤ L ≤ 4mm. Considering that the rotor assembly 400 rotates at high speed when the hub motor is running, a certain distance needs to be maintained between the Hall sensor 351 and the permanent magnet 440 to prevent the Hall sensor 351 from colliding with the rotor assembly 400. After testing, it was found that if the distance between the Hall sensor 351 and the permanent magnet 440 is less than 1mm, collision and friction are likely to occur during the rotation of the rotor assembly 400, resulting in insufficient safety distance. Therefore, 1mm ≤ L is set. When the distance between the Hall sensor 351 and the permanent magnet 440 is greater than 4mm, the magnetic field at the end of the permanent magnet 440 that the Hall sensor 351 can sense is too small, and the Hall sensor 351 cannot accurately detect the position of the permanent magnet 440. Therefore, L ≤ 4mm is set, with a value of 2mm to 3mm being the optimal solution.

[0075] The hub motor proposed in the second aspect of the present invention includes the stator assembly 300 of the first aspect embodiment, includes all the technical solutions of the stator assembly 300, and has all the technical effects of the stator assembly 300, which will not be described in detail here.

[0076] The electric vehicle proposed in the third aspect of the present invention includes a hub motor as described in the second aspect embodiment. The hub motor includes a central shaft 100 and a housing assembly 200, a stator assembly 300, and a gear assembly 500 connected to the central shaft 100. The stator assembly 300 includes a winding 310, a stator core, and a support bracket 340. The support bracket 340 mounts a Hall plate 350 via a Hall plate mounting bracket 341. A Hall sensor 351 is disposed on the Hall plate 350. The fixed installation of the Hall sensor 351 is simpler, easier to operate, and improves assembly efficiency. The use of a Hall plate 350 to mount the Hall sensor 351 in the stator assembly 300 eliminates the need to open a sensor mounting slot in the stator core, avoiding affecting the electromagnetic performance of the stator assembly 300 and improving the performance of the hub motor.

[0077] The embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of the present invention.

Claims

1. A hub motor, characterized in that, include: A stator assembly includes a stator core, windings, a stator bracket, a support bracket, a Hall plate, and at least one Hall sensor. The stator core has a closed yoke, and the outer periphery of the yoke is provided with multiple teeth. The windings are connected to the teeth. The stator bracket is connected to the stator core and is located inside the yoke. The support bracket is connected to the stator bracket, and the support bracket is provided with at least one Hall plate mounting bracket; The Hall plate is connected to the Hall plate mounting bracket; At least one of the Hall sensors is connected to the Hall plate along the radial direction of the stator core. The Hall sensor is located outside the winding. The Hall plate mounting bracket is provided with a first connector. The Hall plate is provided with mounting holes that mate with the first connector. The first connector includes a plurality of columns that are circumferentially distributed. The ends of the columns are provided with stops that abut against the Hall plate. A central shaft is provided, and the stator assembly is fixedly connected to the central shaft. A rotor assembly is supported on the central shaft by bearings. The rotor assembly has a permanent magnet. Along the radial direction of the central shaft, the Hall sensor is positioned corresponding to the permanent magnet. Along the axial direction of the central shaft, the distance between the Hall sensor and the permanent magnet is L, which satisfies 1mm≤L≤4mm. The Hall plate mounting bracket is provided with ribs. The ribs and the first connecting member are arranged on two opposite sides of the Hall plate mounting bracket. The ribs are connected to the support bracket. The support bracket is provided with a plurality of second connecting members, which are distributed circumferentially along the support bracket. The second connecting members are connected to the stator support.

2. The hub motor according to claim 1, characterized in that, The support bracket is provided with a plurality of Hall plate mounting brackets, which are distributed at intervals along the circumference of the support bracket.

3. The hub motor according to claim 2, characterized in that, The support bracket is provided with three Hall plate mounting brackets, and the Hall plate is arc-shaped and connected to the three Hall plate mounting brackets.

4. The hub motor according to claim 1, characterized in that, The support bracket is provided with multiple cross-slot connecting lines, which are electrically connected to the winding.

5. An electric vehicle, characterized in that, It includes a hub motor as described in any one of claims 1 to 4.

Images