Hub motor and scooter

Abstract

The hub motor comprises a motor shaft, a shell, an inner gear ring, a stator assembly, a rotor assembly, a sun wheel, a plurality of planet wheels and a tower footing, and the shell is rotationally assembled on the peripheral side of the motor shaft; the inner gear ring is arranged in the shell and surrounds the peripheral side of the motor shaft; the stator assembly and the rotor assembly are both arranged in the shell, the stator assembly is arranged on the motor shaft, and the rotor assembly is rotationally assembled on the motor shaft and surrounds the peripheral side of the stator assembly; the sun gear is connected with the rotor assembly and surrounds the peripheral side of the motor shaft, the multiple planet gears are assembled on the peripheral side of the sun gear in a meshed mode, and the multiple planet gears are all assembled in the inner gear ring in a meshed mode; the tower footing is fixedly connected with the shell and rotationally assembled on the peripheral side of the motor shaft. The hub motor is simple in overall structure, compact in arrangement, small in overall size, light in weight and high in torque density.

Description

Technical Field

[0001] The utility model relates to the technical field of vehicles, in particular to a hub motor and a scooter. Background Art

[0002] At present, most commuting vehicles, such as electric-assisted bicycles, are driven by hub motors. In actual use, some special working conditions require the hub motor to output high torque. Therefore, some hub motors of commuting vehicles are designed with a reduction structure. However, the hub motors in related technologies have problems such as relatively small reduction speed, large overall weight and volume of the motor, etc. Utility Model Content

[0003] The utility model aims to solve one of the technical problems in the related art at least to a certain extent.

[0004] To this end, an embodiment of the present invention provides a hub motor, which has a simple overall structure, a compact layout, a small overall volume, a light weight, and a high torque density.

[0005] The embodiment of the present utility model further provides a mobility scooter comprising the above-mentioned hub motor.

[0006] The hub motor of the utility model embodiment includes:

[0007] A motor shaft and a housing, wherein the housing is rotatably mounted on the outer circumference of the motor shaft;

[0008] an inner gear ring disposed in the housing and surrounding the outer circumference of the motor shaft;

[0009] A stator assembly and a rotor assembly, both of which are disposed in the housing, the stator assembly being disposed on the motor shaft, and the rotor assembly being rotatably assembled on the motor shaft and surrounding an outer circumference of the stator assembly;

[0010] a sun gear and a plurality of planetary gears, wherein the sun gear is connected to the rotor assembly and surrounds the outer circumference of the motor shaft, the plurality of planetary gears are meshed and assembled on the outer circumference of the sun gear, and the plurality of planetary gears are meshed and assembled in the inner gear ring;

[0011] The tower base is fixedly connected to the shell and rotatably assembled on the outer peripheral side of the motor shaft.

[0012] In some embodiments, the housing comprises:

[0013] a housing, the housing being rotatably assembled on the outer circumference of the motor shaft via a first bearing, the stator assembly, the rotor assembly, the sun gear, and the plurality of planetary gears being disposed within the housing;

[0014] An end cover is sleeved on the motor shaft and sealed at one end of the housing, the inner gear ring is fixed in the end cover, and the tower base is arranged outside the housing and connected to the end cover.

[0015] In some embodiments, the end cover includes an annular portion, the annular portion is inserted into the housing and surrounds the outer circumference of the motor shaft, and the inner ring gear is fixed in the annular portion.

[0016] In some embodiments, the tower base is rotatably assembled on the outer peripheral side of the motor shaft through at least two second bearings.

[0017] In some embodiments, the planetary gear includes a first gear and a second gear, the first gear and the second gear are coaxially arranged, the first gear and the second gear are arranged sequentially in the axial direction of the motor shaft, and the first gear is meshed with the sun gear, and the second gear is meshed with the inner ring gear.

[0018] In some embodiments, the first gear and the second gear are integrally formed;

[0019] And / or, the radial size of the first gear is greater than the radial size of the second gear.

[0020] In some embodiments, the rotor assembly comprises:

[0021] a rotor core, the rotor core surrounding the outer circumference of the stator assembly;

[0022] The rotor support is rotatably assembled on the outer peripheral side of the motor shaft through a plurality of third bearings. The rotor support is provided with an annular groove surrounding the outer peripheral side of the motor shaft, and the sun gear is fixed in the annular groove.

[0023] In some embodiments, if the diameter of the stator assembly is not less than 80 mm, the number of stator slots of the stator assembly is not less than 18, and the number of poles of the stator assembly is not less than 16;

[0024] And / or, if the diameter of the stator assembly is greater than 80 mm, the number of stator slots of the stator assembly is not less than 20, and the number of poles of the stator assembly is not less than 20.

[0025] In some embodiments, a clutch is further included, wherein the clutch is fixed to the outer peripheral side of the motor shaft and is located in the housing;

[0026] and / or, the sun gear and the planet gears are in helical gear meshing;

[0027] And / or, the planetary gears and the inner ring gear are in helical gear meshing.

[0028] The mobility scooter of the embodiment of the present invention includes the hub motor as described in any of the above embodiments.

[0029] Beneficial effects: The wheel hub motor and the scooter of the embodiment of the present invention have a simple overall structure, a compact arrangement, a small overall volume, a light weight, and a high torque density. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a schematic diagram of the overall structure of the hub motor according to an embodiment of the present utility model.

[0031] Figure 2 It is a schematic diagram of the assembly of the tower base, end cover and motor shaft of an embodiment of the utility model.

[0032] Reference numerals:

[0033] 1-motor shaft;

[0034] 2-housing; 21-shell; 22-end cover; 221-annular portion; 23-first bearing;

[0035] 3-Inner ring gear;

[0036] 4- stator assembly;

[0037] 5- rotor assembly; 51- rotor core; 52- rotor bracket; 53- third bearing;

[0038] 6-Sun gear;

[0039] 7- planetary gear; 71- first gear; 72- second gear;

[0040] 8- freewheel base; 81- second bearing;

[0041] 9-Clutch. DETAILED DESCRIPTION

[0042] The embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to be used to explain the present invention, but should not be understood as limiting the present invention.

[0043] like Figure 1 As shown, the hub motor of the embodiment of the present invention includes a motor shaft 1, a housing 2, an inner gear ring 3, a stator assembly 4, a rotor assembly 5, a sun gear 6, a plurality of planetary gears 7 and a tower base 8.

[0044] The housing 2 is rotatably mounted on the outer peripheral side of the motor shaft 1. For example, Figure 1As shown, the housing 2 can be generally cylindrical, and the entire housing 2 can be rotatably assembled on the outer peripheral side of the motor shaft 1 through bearings. When in use, the housing 2 can rotate freely relative to the motor shaft 1.

[0045] The inner ring gear 3 is disposed within the housing 2 and surrounds the outer circumference of the motor shaft 1. For example, the inner ring gear 3 may be annular, with a ring of meshing teeth disposed on the inner circumference of the inner ring gear 3. The inner ring gear 3 may be fixed within the housing 2. The fixing method for the inner ring gear 3 may be interference fit, welding, etc.

[0046] The stator assembly 4 and the rotor assembly 5 are both arranged in the housing 2. The stator assembly 4 is arranged on the motor shaft 1. The rotor assembly 5 is rotatably assembled on the motor shaft 1 and surrounds the outer circumference of the stator assembly 4. For example, Figure 1 As shown, the stator assembly 4 can be assembled on the outer peripheral side of the motor shaft 1 by means of a key and a slot to prevent rotation. When in use, the relative positions of the stator assembly 4 and the motor shaft 1 do not change.

[0047] The rotor assembly 5 can be a cap-shaped structure as a whole. The inner circumference of the rotor assembly 5 can be rotatably assembled with the motor shaft 1 via a bearing, and the outer circumference of the rotor assembly 5 can surround the outer circumference of the stator assembly 4. During use, the rotor assembly 5 can rotate freely relative to the stator assembly 4, thereby satisfying the need to drive the housing 2 to rotate.

[0048] The sun gear 6 is connected to the rotor assembly 5 and surrounds the outer circumference of the motor shaft 1. For example, Figure 1 As shown, the sun gear 6 can be an annular structure, and the sun gear 6 can be sleeved on the outer circumference of the motor shaft 1 and have a clearance fit with the motor shaft 1. The sun gear 6 can be fixedly connected to the rotor assembly 5, so that the sun gear 6 can rotate synchronously with the rotor assembly 5 around the motor shaft 1.

[0049] Multiple planetary gears 7 are meshed and assembled on the outer circumference of the sun gear 6, and all of the planetary gears 7 are meshed and assembled within the ring gear 3. For example, there may be two, three, or four planetary gears 7. All of the planetary gears 7 may be assembled on the outer circumference of the sun gear 6 and arranged at equal intervals along the circumference of the sun gear 6.

[0050] The plurality of planetary gears 7 can be located between the sun gear 6 and the inner ring gear 3, wherein the inner side of each planetary gear 7 can mesh with the sun gear 6, and the outer side of each planetary gear 7 can mesh with the inner ring gear 3. Thus, when the rotor assembly 5 rotates, the sun gear 6 and the plurality of planetary gears 7 can drive the housing 2 in rotation, thereby meeting the need for rotational drive.

[0051] The tower base 8 is fixedly connected to the housing 2 and is rotatably mounted on the outer peripheral side of the motor shaft 1. Figure 1As shown, the tower base 8 can be a circular columnar structure, and the tower base 8 can be fixedly connected to the right end of the housing 2, and the fixed connection method can be fastening, clamping and limiting, etc. When in use, the tower base 8 can rotate synchronously with the housing 2.

[0052] The design of the hub motor, the sun gear 6 and the multiple planetary gears 7 in the embodiment of the utility model meets the need of achieving high torque output by reducing deceleration. Secondly, it also makes the overall structural layout compact and the distribution reasonable, which is conducive to reducing the overall volume of the hub motor and simplifying the overall structure, thereby also reducing the weight of the hub motor and improving the torque density.

[0053] Secondly, by connecting the tower base 8 to the shell 2, the tower base 8 and the shell 2 rotate synchronously, which facilitates the installation of the flywheel and the like of the scooter. During use, it can also balance the force on the hub motor, that is, it avoids the situation where one side of the hub motor where the rotor assembly 5 and the stator assembly 4 are arranged is heavier and easily causes the center to deviate, thereby improving the safety and stability of the scooter.

[0054] In some embodiments, as Figure 1 As shown, the housing 2 includes an outer shell 21 and an end cover 22 .

[0055] The housing 21 is rotatably mounted on the outer circumference of the motor shaft 1 via a first bearing 23. The stator assembly 4, rotor assembly 5, sun gear 6, and multiple planetary gears 7 are all disposed within the housing 21. For example, the housing 21 as a whole may be a cap-shaped structure, with an annular shell wall disposed on the left side of the housing 21. The annular shell wall may be sleeved on the outer circumference of the motor shaft 1, and the annular housing wall 2 and the motor shaft 1 may be rotatably mounted via a first bearing 23.

[0056] The end cover 22 is sleeved on the motor shaft 1 and sealed to one end of the housing 21. The inner ring gear 3 is fixed in the end cover 22. The tower base 8 is arranged on the outside of the shell 2 and is connected to the end cover 22. For example, the right side of the housing 21 is an open structure. The end cover 22 can be roughly disc-shaped. The end cover 22 can be assembled on the right side of the housing 21 and seal the right side opening of the housing 21. The fixing method of the end cover 22 can be interference fit, fastener fixation, etc. The inner ring gear 3 can be fixed in the end cover 22. The fixing method of the inner ring gear 3 can be welding, interference fit, etc. The tower base 8 can be directly fixedly connected to the end cover 22, and the tower base 8 can be located on the right side of the end cover 22 as a whole.

[0057] The split setting of the housing 2 facilitates the installation and disassembly of the stator assembly 4, rotor assembly 5, etc. on the one hand, and also facilitates the reserved installation position for the inner gear ring 3 on the end cover 22, reducing the complexity of the installation position arrangement.

[0058] In some embodiments, the end cover 22 includes an annular portion 221, which is inserted into the housing 21 and surrounds the outer circumference of the motor shaft 1, and the inner gear ring 3 is fixed in the annular portion 221. Figure 1 As shown, the annular portion 221 can be integrally formed on the left side of the end cover 22. The annular portion 221 can be generally annular and cylindrical and can extend in the left and right directions. When the end cover 22 is assembled on the right side of the outer shell 21, the annular portion 221 as a whole can be inserted into the outer shell 21, and the above-mentioned inner gear ring 3 can be interference fitted in the annular portion 221, thereby facilitating the installation and fixation of the inner gear ring 3.

[0059] In some embodiments, the tower base 8 is rotatably mounted on the outer peripheral side of the motor shaft 1 through at least two second bearings 81. Figure 2 As shown, the tower base 8 can be rotatably assembled on the outer peripheral side of the motor shaft 1 through two second bearings 81, one of the second bearings 81 can be arranged adjacent to the end cover 22, and the other second bearing 81 can be arranged adjacent to the right end of the tower base 8, thereby enhancing the structural stability of the tower base 8 assembly and ensuring the coaxiality of the tower base 8 and the motor shaft 1 assembly.

[0060] In some embodiments, the planetary gear 7 includes a first gear 71 and a second gear 72, the first gear 71 and the second gear 72 are coaxially arranged, the first gear 71 and the second gear 72 are arranged sequentially in the axial direction of the motor shaft 1, and the first gear 71 is engaged with the sun gear 6, and the second gear 72 is engaged with the inner ring gear 3.

[0061] For example, Figure 1 As shown, the planetary gear 7 can include two independent gears in the left and right directions, and the two independent gears are a first gear 71 and a second gear 72, wherein the first gear 71 can be arranged on the left side of the second gear 72, and the axes of the first gear 71 and the second gear 72 can be in the same straight line.

[0062] During assembly, the first gears 71 of the multiple planetary gears 7 can be arranged on the outer periphery of the sun gear 6 and mesh with the sun gear 6, while the multiple second gears 72 can mesh with the inner ring gear 3. Thus, a primary reduction can be achieved by the sun gear 6 and the first gears 71, while a secondary reduction can be achieved by the second gears 72 and the inner ring gear 3, thereby greatly reducing the reduction ratio of the hub motor and further meeting the needs of high torque output.

[0063] In some embodiments, the first gear 71 and the second gear 72 are integrally formed. For example, the planetary gear 7 can be made of plastic, and the first gear 71 and the second gear 72 can be integrally formed by injection molding. In other embodiments, the planetary gear 7 can also be made of a metal alloy, powder metallurgy, or the like. In this case, the first gear 71 and the second gear 72 can be integrally formed by casting or other methods. This ensures the structural strength of the connection between the first gear 71 and the second gear 72, and also ensures the coaxial accuracy of the first gear 71 and the second gear 72.

[0064] In some embodiments, the radial dimension of the first gear 71 is greater than the radial dimension of the second gear 72. Figure 1 As shown, the planetary gear 7 is in the shape of a stepped shaft, and the outer diameter of the first gear 71 is larger than the outer diameter of the second gear 72 as a whole. Therefore, on the one hand, the overall radial dimension of the second gear 72 and the inner ring gear 3 after assembly can be reduced, thereby meeting the use requirements of assembly in the annular portion 221. On the other hand, the first gear 71 and the inner ring gear 3 can be stopped in the left and right directions, thereby avoiding the situation of displacement in the left and right directions and ensuring the stability of the structure.

[0065] In some embodiments, as Figure 1 As shown, the rotor assembly 5 includes a rotor core 51 and a rotor support 52 .

[0066] The rotor core 51 can be annular in shape and surround the outer circumference of the stator assembly 4. The rotor core 51 can be plugged into and assembled with multiple permanent magnets, each of which can be a straight-piece structure, which can effectively reduce the production cost of the permanent magnets and facilitate the side-by-side arrangement of the permanent magnets inside the rotor core 51.

[0067] The rotor bracket 52 is rotatably mounted on the outer circumference of the motor shaft 1 via a plurality of third bearings 53 . The rotor bracket 52 is provided with an annular groove surrounding the outer circumference of the motor shaft 1 , and the sun gear 6 is fixed in the annular groove.

[0068] For example, Figure 1 As shown, the rotor bracket 52 can also be roughly annular in structure, the rotor core 51 can be fixed on the outer peripheral side of the rotor bracket 52, and the inner peripheral side of the rotor bracket 52 can be rotatably assembled on the outer peripheral side of the motor shaft 1 through two third bearings 53. The two third bearings 53 can be arranged at intervals in the left and right directions.

[0069] In this way, the concentricity of the rotor assembly 5 and the motor shaft 1 can be improved, and the support strength of the motor shaft 1 for the rotor assembly 5 can be higher, thereby effectively reducing motor vibration and noise problems caused by imbalance of the rotor assembly 5 under high speed conditions.

[0070] In some embodiments, if the diameter of the stator assembly 4 is not less than 80 mm, the number of stator slots of the stator assembly 4 is not less than 18, and the number of poles of the stator assembly 4 is not less than 16.

[0071] In some embodiments, if the diameter of the stator assembly 4 is greater than 80 mm, the number of stator slots of the stator assembly 4 is not less than 20, and the number of poles of the stator assembly 4 is not less than 20. Specifically, in this embodiment, the diameter of the stator assembly 4 is greater than 80 mm. In this case, the number of stator slots can be 27, and the number of poles of the stator assembly 4 can be 30.

[0072] By adopting high slot poles in the stator assembly 4, under the same motor configuration, a relatively high torque can be output at a high motor speed, further meeting the use requirements of high torque output.

[0073] In some embodiments, the hub motor further includes a clutch 9, which is fixed to the outer peripheral side of the motor shaft 1 and located inside the housing 2. Figure 1 As shown, the clutch 9 is provided in the housing 2. The clutch 9 as a whole can be located between the ring gear and the end cover 22. The clutch 9 can also be assembled on the outer peripheral side of the motor shaft 1 through the cooperation of keys and grooves to prevent rotation. When in use, the clutch 9 can play a role in limiting the rotation of the housing.

[0074] In some embodiments, the sun gear 6 and the planet gear 7 are in helical meshing, thereby further increasing the reduction ratio.

[0075] In some embodiments, the planetary gears 7 and the inner ring gear 3 are meshed with helical teeth, thereby further increasing the reduction ratio. Through the meshing of the helical teeth, the overall reduction ratio of the hub motor can reach 8.5 to 15.

[0076] The following describes a mobility scooter according to an embodiment of the present invention.

[0077] The scooter of the present invention includes a hub motor, which may be any of the hub motors described in the above embodiments. The scooter may be an electric bicycle (EBIKE). In other embodiments, the scooter may also be an electric-assisted bicycle or other type of scooter.

[0078] Although the above embodiments have been shown and described, it is understood that the above embodiments are illustrative and cannot be understood as limitations on the present invention. Changes, modifications, substitutions and variations of the above embodiments made by ordinary technicians in this field are all within the scope of protection of the present invention.

Claims

1. A hub motor, characterized in that: include: A motor shaft and a housing, wherein the housing is rotatably mounted on the outer circumference of the motor shaft; an inner gear ring disposed in the housing and surrounding the outer circumference of the motor shaft; A stator assembly and a rotor assembly, both of which are disposed in the housing, the stator assembly being disposed on the motor shaft, and the rotor assembly being rotatably assembled on the motor shaft and surrounding an outer circumference of the stator assembly; a sun gear and a plurality of planetary gears, wherein the sun gear is connected to the rotor assembly and surrounds the outer circumference of the motor shaft, the plurality of planetary gears are meshed and assembled on the outer circumference of the sun gear, and the plurality of planetary gears are meshed and assembled in the inner gear ring; The tower base is fixedly connected to the shell and rotatably assembled on the outer peripheral side of the motor shaft.

2. The hub motor according to claim 1, characterized in that: The housing comprises: a housing, the housing being rotatably assembled on the outer circumference of the motor shaft via a first bearing, the stator assembly, the rotor assembly, the sun gear, and the plurality of planetary gears being disposed within the housing; An end cover is sleeved on the motor shaft and sealed at one end of the housing, the inner gear ring is fixed in the end cover, and the tower base is arranged outside the housing and connected to the end cover.

3. The hub motor according to claim 2, characterized in that: The end cover includes an annular portion, which is inserted into the housing and surrounds the outer circumference of the motor shaft. The inner gear ring is fixed in the annular portion.

4. The hub motor according to claim 2, characterized in that: The tower base is rotatably assembled on the outer peripheral side of the motor shaft through at least two second bearings.

5. The hub motor according to claim 1, characterized in that: The planetary gear includes a first gear and a second gear, the first gear and the second gear are coaxially arranged, the first gear and the second gear are arranged sequentially in the axial direction of the motor shaft, and the first gear is meshed with the sun gear, and the second gear is meshed with the inner ring gear.

6. The hub motor according to claim 5, characterized in that: The first gear and the second gear are integrally formed; And / or, the radial size of the first gear is greater than the radial size of the second gear.

7. The hub motor according to claim 1, characterized in that: The rotor assembly comprises: a rotor core, the rotor core surrounding the outer circumference of the stator assembly; The rotor support is rotatably assembled on the outer peripheral side of the motor shaft through a plurality of third bearings. The rotor support is provided with an annular groove surrounding the outer peripheral side of the motor shaft, and the sun gear is fixed in the annular groove.

8. The hub motor according to claim 1, characterized in that: If the diameter of the stator assembly is not less than 80 mm, the number of stator slots of the stator assembly is not less than 18, and the number of poles of the stator assembly is not less than 16; And / or, if the diameter of the stator assembly is greater than 80 mm, the number of stator slots of the stator assembly is not less than 20, and the number of poles of the stator assembly is not less than 20.

9. The hub motor according to any one of claims 1 to 8, characterized in that: Also included is a clutch, the clutch being fixed to the outer circumference of the motor shaft and located inside the housing; and / or, the sun gear and the planet gears are in helical gear meshing; And / or, the planetary gears and the inner ring gear are in helical gear meshing.

10. A mobility scooter, characterized in that: The invention comprises a hub motor as claimed in any one of claims 1 to 9.

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