Wheel hub motor and walking device

Abstract

This utility model discloses a hub motor and a walking device, relating to the field of walking device technology. The hub motor is used to drive the drive wheel of the walking device to rotate. It includes a housing and a planetary reduction assembly. The housing contains a motor rotor. The planetary reduction assembly includes an internal gear ring, at least one planetary gear, and a sun gear. The internal gear ring and the housing are integrally formed. Each planetary gear meshes with the sun gear and the internal gear ring, respectively. The motor rotor and the sun gear are integrally formed.

Description

Technical Field

[0001] This utility model relates to the field of walking device technology, and in particular to a hub motor and a walking device. Background Technology

[0002] In existing hub motor structures, the planetary gear reducer assembly is typically connected to the motor stator, rotor, and other components via bolts, clips, or other fasteners between the internal gear ring and the outer casing. However, this method is prone to loosening of the connection points due to vibration and impact loads during long-term operation, leading to poor gear meshing, increased noise, decreased transmission accuracy, and even gear damage or failure. This not only easily introduces assembly errors but also results in reduced transmission accuracy. Utility Model Content

[0003] The main purpose of this utility model is to propose a hub motor and a walking device, which aims to solve the technical problem of reduced transmission accuracy in the connection method between the split internal gear ring and the outer shell in related technologies.

[0004] To achieve the above objectives, the present invention proposes a hub motor for driving the rotation of the drive wheel of a walking device, the hub motor comprising:

[0005] A housing, wherein a motor rotor is disposed within the housing;

[0006] A planetary gear reducer assembly includes an internal gear ring, at least one planet gear, and a sun gear. The internal gear ring and the housing are integrally formed. Each planet gear meshes with the sun gear and the internal gear ring, respectively. The motor rotor and the sun gear are integrally formed.

[0007] In one embodiment, the planetary reduction assembly further includes a planet carrier, the hub motor further includes a central shaft, the planet carrier is connected to the central shaft, and each of the planetary gears is rotatably disposed on the planet carrier.

[0008] In one embodiment, a connecting hole is provided on the outer wall at each of the opposite ends of the housing, and the opposite ends of the central shaft pass through one of the connecting holes.

[0009] In one embodiment, the hub motor further includes an isolation plate disposed within the housing, the isolation plate dividing the inner cavity of the housing into a motor cavity and a reducer cavity, the planetary reduction assembly being located within the reducer cavity, and the hub motor further includes a motor stator, the motor rotor and the motor stator being both located within the motor cavity.

[0010] In one embodiment, the isolation plate respectively seals and connects the inner wall of the motor cavity and the inner wall of the reducer cavity.

[0011] In one embodiment, the housing further includes a motor stator and a central shaft, the motor stator being fixed to the central shaft, and the motor rotor being coaxially arranged with the motor stator.

[0012] In one embodiment, the hub motor further includes a Hall magnetic encoder plate disposed within the housing and located at the end of the motor stator away from the motor rotor.

[0013] This utility model also proposes a walking device, the walking device comprising:

[0014] frame;

[0015] Drive wheel;

[0016] As described above, in the hub motor, the drive wheel is connected to the hub motor, and the two opposite ends of the central shaft of the hub motor are respectively connected to the frame.

[0017] In one embodiment, the walking device further includes two bearings, which are respectively sleeved on both ends of the central shaft, and a double-lip oil seal is provided between the frame and the central shaft.

[0018] In one embodiment, the frame has a limiting groove, the drive wheel is located in the limiting groove, and the two opposite ends of the central shaft are connected to the two groove walls of the limiting groove.

[0019] The hub motor provided by this utility model solves the problems of low power transmission efficiency, complex structure, and insufficient reliability in traditional hub motors by adopting an integral structure of the motor rotor and sun gear, and a design where planetary gears mesh with the sun gear and internal gear ring respectively. Specifically, the integral structure of the motor rotor and sun gear reduces mechanical connection links, reduces energy loss during transmission, and improves transmission efficiency. At the same time, the meshing design of the planetary gears with the sun gear and internal gear ring allows power to be effectively transmitted to the drive shaft, further amplifying torque output and meeting the power requirements of vehicles under different operating conditions. The integral structure of the internal gear ring and housing enhances the structural stability of the entire hub motor, reduces the number of parts, reduces assembly difficulty and cost, and improves the reliability and durability of the system. In addition, this design makes the hub motor structure more compact, saves space, and facilitates efficient power transmission within a limited space, improving the integration and performance of the entire hub motor system. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0021] Figure 1 A schematic diagram of the hub motor provided by this utility model;

[0022] Figure 2 A schematic diagram of the walking device provided by this utility model;

[0023] Figure 3 A side view of the walking device provided by this utility model.

[0024] Explanation of icon numbers:

[0025] 100. Hub motor; 1. Housing; 11. Motor rotor; 12. Motor stator; 13. Motor cavity; 14. Reducer cavity; 2. Central shaft; 3. Planetary reduction gear assembly; 31. Internal gear ring; 32. Sun gear; 33. Planetary gears; 34. Planet carrier; 4. Hall effect magnetic encoder board; 5. Isolation plate;

[0026] 200. Walking device; 210. Frame; 220. Drive wheel; 230. Bearing; 240. Double lip oil seal.

[0027] The realization of the purpose, functional features and advantages of this utility model will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0028] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present utility model.

[0029] It should be noted that if the embodiments of this utility model involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of the components in a specific posture. If the specific posture changes, the directional indicators will also change accordingly.

[0030] Furthermore, if the embodiments of this utility model involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the use of "and / or" or "and / or" throughout the text includes three parallel solutions. For example, "A and / or B" includes solution A, solution B, or a solution where both A and B are satisfied simultaneously. Furthermore, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this utility model.

[0031] This utility model proposes a hub motor 100.

[0032] Please see Figure 1 In one embodiment of the present invention, the hub motor 100 is used to drive the drive wheel 220 of the walking device 200 to rotate. It includes a housing 1 and a planetary reduction assembly 3. The housing 1 is provided with a motor rotor 11. The planetary reduction assembly 3 includes an internal gear ring 31, at least one planetary gear 33 and a sun gear 32. The internal gear ring 31 and the housing 1 are integrally formed. Each planetary gear 33 meshes with the sun gear 32 and the internal gear ring 31 respectively. The motor rotor 11 and the sun gear 32 are integrally formed.

[0033] In this embodiment, it should be noted that the hub motor 100 can be applied not only to tracked robots but also to smart home devices such as robotic vacuum cleaners; no limitation is made here. The housing 1 is the main frame of the hub motor 100, providing installation and support for internal components such as the motor rotor 11 and the planetary reduction gear assembly 3. The motor rotor 11 converts electrical energy into mechanical energy. When the motor is energized, the motor rotor 11 rotates under the influence of a magnetic field, thereby converting electrical energy into mechanical energy to power the motor. The planetary reduction gear assembly 3 converts the high-speed, low-torque output of the motor rotor 11 into a low-speed, high-torque output. The internal gear ring 31 provides a stable support structure for the planetary gears 33, ensuring accurate meshing and transmission during operation. The integrated design of the internal gear ring 31 and the housing 1 not only improves the compactness of the structure but also reduces assembly steps, lowering assembly errors and the possibility of loosening. This design makes the entire hub motor 100 system more stable and reliable. The sun gear 32 and the motor rotor 11 are integrally formed. The rotation of the motor rotor 11 directly drives the sun gear 32 to rotate. The planetary reduction assembly 3 has high transmission efficiency, which can more effectively convert the electrical energy of the motor into mechanical energy. In order to achieve high torque output, the high speed and low torque output of the motor rotor 11 is converted into low speed and high torque output through the reduction effect of the planetary reduction assembly 3. The motor rotor 11 and the sun gear 32 are integrally formed. The rotation of the sun gear 32 drives the planet gears 33 to rotate. The planet gears 33 revolve around the sun gear 32 and rotate on their own axes, and mesh with the internal gear ring 31. Since the internal gear ring 31 is stationary relative to the housing 1, the revolution and rotation of the planet gears 33 enable the central shaft 2 to obtain low speed and high torque output. The planetary reduction assembly 3 includes the sun gear 32, the planet gears 33 and the planet carrier 34. The rotation of the motor rotor 11 drives the sun gear 32 to rotate. The planet gears 33 revolve around the sun gear 32 and rotate on their own axes, and finally transmit the power to the central shaft 2 through the planet carrier 34. The number of planetary gears 33 is not limited, and may include, but is not limited to, one, two, or three. It should be noted that the outer wall of the internal gear ring 31 and the housing 1 can be integrally formed by stamping, injection molding, etc., which is not limited here. The implementation methods for integrally forming the motor rotor 11 and the sun gear 32 include, but are not limited to, stamping, injection molding, precision casting, etc. Alternatively, they can be formed by interference fit connection followed by machining; that is, the motor rotor 11 and the sun gear 32 are initially connected by interference fit, and then integrally machined to ensure coaxiality and fitting accuracy. This is not limited here. Compared to the traditional separate structure of the motor and reducer, the planetary reduction assembly 3 can more effectively convert the electrical energy of the motor into mechanical energy to drive the drive wheel 220, while saving space and improving the system integration.

[0034] The hub motor 100 provided by this utility model solves the problems of low power transmission efficiency, complex structure, and insufficient reliability in traditional hub motors 100 by adopting an integral structure of the motor rotor 11 and the sun gear 32, and the design of planetary gears 33 meshing with the sun gear 32 and the internal gear ring 31 respectively. Specifically, the integral structure of the motor rotor 11 and the sun gear 32 reduces mechanical connection links, reduces energy loss during transmission, and improves transmission efficiency. At the same time, the meshing design of the planetary gears 33 with the sun gear 32 and the internal gear ring 31 enables power to be effectively transmitted to the drive shaft, further amplifying the torque output and meeting the power requirements of the vehicle under different operating conditions. The integral structure of the internal gear ring 31 and the housing 1 enhances the structural stability of the entire hub motor 100, reduces the number of parts, reduces assembly difficulty and cost, and improves the reliability and durability of the system. In addition, this design makes the hub motor 100 more compact, saves space, and facilitates efficient power transmission in a limited space, improving the integration and performance of the entire hub motor 100 system.

[0035] In one embodiment of the present invention, the planetary reduction assembly 3 further includes a planet carrier 34, and the hub motor 100 further includes a central shaft 2. The planet carrier 34 is connected to the central shaft 2, and each planetary gear 33 is rotatably mounted on the planet carrier 34.

[0036] In this embodiment, combined with Figure 1 The planetary carrier 34 ensures that the planetary gears 33 can smoothly revolve and rotate around the sun gear 32. This design makes power transmission smoother and reduces vibration and noise. It is understood that the hub motor 100 has a central shaft 2, the planetary carrier 34 is mounted on the central shaft 2, and each planetary gear 33 is rotatably mounted on the planetary carrier 34. In one embodiment, a rolling bearing 230 (such as a deep groove ball bearing 230, needle roller bearing 230, cylindrical roller bearing 230, etc.) is installed between the central hole of the planetary gear 33 and the mounting shaft of the planetary carrier 34. The inner ring of the planetary gear 33 engages with the shaft of the planetary carrier 34 through the bearing 230, and the outer ring rotates with the planetary gear 33. In another embodiment, a wear-resistant bushing (such as a copper bushing, powder metallurgy bushing, engineering plastic bushing, etc.) is press-fitted or injection-molded into the central hole of the planetary gear 33. The bushing forms a clearance fit with the mounting shaft of the planetary carrier 34, and grease is used to reduce sliding friction. No limitation is made here; the configuration can be made according to specific needs.

[0037] In one embodiment of the present invention, a connecting hole is provided on the outer wall of the opposite ends of the housing 1, and the opposite ends of the central shaft 2 pass through a connecting hole.

[0038] In this embodiment, combined with Figure 1To enhance structural strength, the connecting holes provide support points at both ends of the central shaft 2, allowing both ends of the central shaft 2 to pass through the housing 1. During operation, the force from the load on the central shaft 2 can be evenly transmitted to the housing 1 through the connecting holes, avoiding stress concentration and thus enhancing the overall structural strength of the motor. It is understood that the machining process for the connecting holes can be drilling or milling; this is not limited here.

[0039] In one embodiment of the present invention, the hub motor 100 further includes an isolation plate 5 disposed in the housing 1. The isolation plate 5 divides the inner cavity of the housing 1 into a motor cavity 13 and a reducer cavity 14. The planetary reduction assembly 3 is located in the reducer cavity 14. The hub motor 100 also includes a motor stator 12. The motor rotor 11 and the motor stator 12 are both located in the motor cavity 13.

[0040] In this embodiment, combined with Figure 1 To protect motor performance, an isolation plate 5 is installed as a physical barrier, dividing the inner cavity of the housing 1 into two independent spaces: the motor cavity 13 and the reducer cavity 14. The planetary reduction assembly 3 is located in the reducer cavity 14, while the motor rotor 11 and motor stator 12 are located in the motor cavity 13. Since the reducer cavity 14 requires sufficient grease to reduce wear and friction on gears and other components, any grease that enters could adhere to the motor stator 12, motor rotor 11, and other components, affecting the motor's heat dissipation and insulation performance, and even leading to motor failure. The isolation plate 5 spatially prevents the free flow of grease between the two cavities, effectively preventing grease leakage and ensuring the motor operates in a dry and clean environment, thereby extending the motor's service life and improving its operational stability and reliability. The connection between the isolation plate 5 and the inner wall of the housing 1 includes, but is not limited to, interference fit connections, bolted connections, welding, and bonding, etc., and is not limited here. Figure 1 It is understood that a central shaft 2 is provided inside the housing 1. This central shaft 2 is actually the central shaft 2 of the hub motor 100, with both ends extending out of the housing 1 to cooperate with other structures. The isolation plate 5 is sleeved on the central shaft 2, and sealing rings (O-rings, lip rings, etc.) and sealant can be provided at the perforations, which are not limited here.

[0041] In one embodiment of this utility model, the isolation plate 5 seals the inner wall of the motor cavity 13 and the inner wall of the reducer cavity 14 respectively.

[0042] In this embodiment, to effectively isolate the motor cavity 13 and the reducer cavity 14, the isolation plate 5 is actually a bidirectional sealing isolation plate 5. In one embodiment, a sealing groove is provided on the edge of the isolation plate 5, and O-rings, lip rings, etc. are installed in the sealing groove, and then the isolation plate 5 is assembled with the inner wall of the cavity. In another embodiment, sealant is applied to the mating surfaces of the isolation plate 5 with the inner walls of the motor cavity 13 and the reducer cavity 14. After application, the sealant can fill the minor unevenness and gaps on the mating surfaces, and after curing, it forms a continuous sealing film to achieve the purpose of sealing.

[0043] In one embodiment of this utility model, the housing 1 is further provided with a motor stator 12 and a central shaft 2. The motor stator 12 is fixed to the central shaft 2, and the motor rotor 11 is coaxially arranged with the motor stator 12.

[0044] In this embodiment, combined with Figure 1 It is understood that the central shaft 2 is actually a central shaft 2 passing through the opposite sides of the housing 1 of the hub motor 100, with both ends extending out of the housing 1; when the hub motor 100 is used in conjunction with other structures, the central shaft 2 can connect with other structures and transmit power. To simplify the transmission structure, the stator is directly fixed to the central shaft 2, eliminating the complex support structure between the stator and the housing 1 in traditional motors, making the overall layout of the hub motor 100 more compact, especially suitable for the limited installation space inside the hub. The motor stator 12 and the central shaft 2 have no relative rotational tendency. In one embodiment, a stator bearing 230 is installed at the central shaft of the motor stator 12, and the motor stator 12 together with the stator bearing 230 is fitted onto the central shaft 2. In another embodiment, the motor stator 12 is directly fixed to the outer wall of the central shaft 2 by bolts.

[0045] In one embodiment of the present invention, the hub motor 100 further includes a Hall magnetic encoder plate 4, which is disposed inside the housing 1 and located at the end of the motor stator 12 away from the motor rotor 11.

[0046] In this embodiment, combined with Figure 1 To accurately measure the position of the motor rotor 11, the Hall magnetic encoder board 4 utilizes the Hall effect to detect changes in the magnetic field. When a magnetic field acts on the Hall element, a Hall voltage is generated across the Hall element. By detecting the magnitude and direction of the Hall voltage, the strength and direction of the magnetic field can be determined. It should be noted that the number of Hall magnetic encoder boards 4 includes, but is not limited to, one, two, three, or more.

[0047] Specifically, when the hub motor 100 receives a signal from the controller, it obtains position information through the Hall magnetic encoder board 4, thereby regulating the current to achieve electromagnetic field commutation. The permanent magnet inside the motor rotor 11 and the housing 1 of the motor rotor 11 are subjected to magnetic force in the alternating magnetic field, driving the motor rotor 11 to rotate. Since the motor rotor 11 and the sun gear 32 are integrally formed, the sun gear 32 rotates, which in turn drives the planet gears 33 to rotate, thereby driving the internal gear ring 31 meshing with the planet gears 33 to rotate as well. Since the internal gear ring 31 and the housing 1 are integrally formed, the tight connection between the internal gear ring 31 and the housing 1 ensures that the housing 1 can rotate synchronously with the internal gear ring 31. When the hub motor 100 is engaged with the drive wheel 220, the housing 1 of the hub motor 100 can drive the drive wheel 220 to rotate accordingly.

[0048] This utility model also proposes a walking device 200, which includes a frame 210, a drive wheel 220, and a hub motor 100 as described above. The specific structure of the hub motor 100 is as described in the above embodiments. Since this walking device 200 adopts all the technical solutions of all the above embodiments, it has at least all the beneficial effects brought about by the technical solutions of the above embodiments, which will not be described in detail here. The drive wheel 220 is connected to the hub motor 100, and the two opposite ends of the central shaft 2 of the hub motor 100 are respectively connected to the frame 210.

[0049] In this embodiment, it is understood that the walking device 200 includes, but is not limited to, tracked walking devices, such as weeding walking devices, snow removal walking devices, and other tracked walking devices. Combined with Figure 2 and Figure 3 To simplify the transmission structure and improve transmission efficiency, both ends of the central shaft 2 can be mounted on the frame 210 via bearings 230. The types of bearings 230 include, but are not limited to, deep groove ball bearings 230 and tapered roller bearings 230. Both ends of the central shaft 2 can also be fixedly connected to mounting seats on the frame 210 via bolts. Regarding the connection between the drive wheel 220 and the central shaft 2, in one embodiment, a keyway is machined on the central shaft 2, and a corresponding keyway is machined in the hub of the drive wheel 220, connecting the drive wheel 220 and the central shaft 2 together via a key. In another embodiment, the drive wheel 220 and the central shaft 2 can be connected via an interference fit or a movable sleeve. It is understood that the rim of the drive wheel 220 can be connected to the hub motor 100 via circumferential bolts, an interference fit, or welding, etc., which is not limited here.

[0050] In one embodiment of the present invention, the walking device 200 further includes two bearings 230, which are respectively sleeved on both ends of the central shaft 2, and a double-lip oil seal 240 is also provided between the frame 210 and the central shaft 2.

[0051] In this embodiment, combined with Figure 2 and Figure 3 To support the central shaft 2 and ensure it maintains the correct axial position, allowing the drive wheel 220 to rotate smoothly, bearings 230 are installed at opposite ends of the central shaft 2. To prevent lubricating oil leakage, a double-lip oil seal 240 is provided between the frame 210 and the central shaft 2. The material of the double-lip oil seal 240 includes, but is not limited to, nitrile rubber, fluororubber, etc., and is not specified here.

[0052] In one embodiment of this utility model, the frame 210 is provided with a limiting groove, the drive wheel 220 is limited in the limiting groove, and the opposite ends of the central shaft 2 are connected to the two groove walls of the limiting groove.

[0053] In this embodiment, combined with Figure 2 and Figure 3 Understandably, in order to precisely constrain the movement of the drive wheel 220 and improve walking stability, the frame 210 is provided with a limiting groove. That is, the frame 210 includes three frame segments 210 connected in sequence, and the three frame segments 210 enclose the limiting groove in a U-shape. The opposite ends of the central shaft 2 protrude from the housing 1 of the hub motor 100 and are connected to the two groove walls of the limiting groove by means of bolts, bearings 230, etc., which are not limited here.

[0054] It should be noted that traditional hub motors typically employ a separate structure for the motor rotor, coupling, and reducer input shaft. The mechanical connection of the coupling leads to energy loss, and additional bearings are required to support the reducer input shaft, increasing the number of parts. Assembly errors can easily cause gear meshing deviations, thereby reducing reliability. In contrast, the aforementioned embodiment of this application integrates the motor rotor 11 and sun gear 32, and the internal gear ring 31 and housing 1, eliminating the need for couplings and additional bearings, improving transmission efficiency, and reducing the number of required parts.

[0055] The above description is merely an exemplary embodiment of the present utility model and does not limit the patent scope of the present utility model. Any equivalent structural transformations made based on the technical concept of the present utility model and the contents of the present utility model specification and drawings, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present utility model.

Claims

1. A hub motor for driving the rotation of the drive wheel of a walking device, characterized in that, The hub motor includes: A housing, wherein a motor rotor is disposed within the housing; A planetary gear reducer assembly includes an internal gear ring, at least one planet gear, and a sun gear. The internal gear ring and the housing are integrally formed. Each planet gear meshes with the sun gear and the internal gear ring, respectively. The motor rotor and the sun gear are integrally formed.

2. The hub motor as described in claim 1, characterized in that, The planetary reduction gear assembly also includes a planet carrier, and the hub motor also includes a central shaft. The planet carrier is connected to the central shaft, and each of the planetary gears is rotatably mounted on the planet carrier.

3. The hub motor as described in claim 2, characterized in that, A connecting hole is provided on the outer wall at each of the opposite ends of the housing, and the two opposite ends of the central shaft pass through one of the connecting holes.

4. The hub motor as described in any one of claims 1 to 3, characterized in that, The hub motor also includes an isolation plate disposed within the housing, the isolation plate dividing the inner cavity of the housing into a motor cavity and a reducer cavity, the planetary reduction assembly being located within the reducer cavity, and the hub motor also includes a motor stator, the motor rotor and the motor stator being located within the motor cavity.

5. The hub motor as described in claim 4, characterized in that, The isolation plate respectively seals and connects the inner wall of the motor cavity and the inner wall of the reducer cavity.

6. The hub motor as described in any one of claims 1 to 3, characterized in that, The housing also includes a motor stator and a central shaft. The motor stator is fixed to the central shaft, and the motor rotor is coaxially arranged with the motor stator.

7. The hub motor as described in claim 6, characterized in that, The hub motor also includes a Hall magnetic encoder plate, which is disposed inside the housing and located at the end of the motor stator away from the motor rotor.

8. A walking device, characterized in that, The walking device includes: frame; Drive wheel; The hub motor as described in any one of claims 1 to 7, wherein the drive wheel is connected to the hub motor, and the two opposite ends of the central shaft of the hub motor are respectively connected to the frame.

9. The walking device as described in claim 8, characterized in that, The walking device also includes two bearings, which are respectively sleeved on both ends of the central shaft, and a double-lip oil seal is provided between the frame and the central shaft.

10. The walking device as described in claim 8, characterized in that, The frame has a limiting groove, the drive wheel is located in the limiting groove, and the two ends of the central shaft are connected to the two groove walls of the limiting groove.

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