A high-precision planetary reduction wheel hub motor

Abstract

The utility model discloses a high accuracy planetary reduction hub motor relates to hub motor technical field. The motor includes planetary stator subassembly, inner rotor subassembly and outer rotor subassembly. The planet carrier and output shaft of planetary stator subassembly adopt aluminum alloy die casting integrated molding, and the planet carrier is formed rigid frame by first layer frame, second layer frame and the connecting column between, and the frame is equipped with planetary gear, and the inside of output shaft is equipped with the axle core groove for wiring. The motor shaft one end of inner rotor subassembly is equipped with sun gear and engages with planetary gear, and the other end is supported by bearing, and the motor shaft is supported in the stator cylinder sleeve of planet carrier through double bearing, and utilizes compression spring to eliminate bearing axial clearance. The inner tooth ring that is engaged with planetary gear is formed on the inner wall of rotor shell of outer rotor subassembly. The utility model discloses through integrated structure to strengthen the overall strength and rigidity, improves transmission accuracy and stability through bearing pre -tightening mechanism, solves the problem that traditional hub motor structure is easy to fail, and the precision is poor and the problem of big noise.

Description

Technical Field

[0001] This utility model relates to the field of hub motor technology, and in particular to a high-precision planetary gear hub motor. Background Technology

[0002] Hub motors with built-in planetary gears are usually called planetary geared hub motors or composite transmission hub motors. Their core feature is that the planetary gear transmission mechanism is integrated inside the hub motor to achieve deceleration and torque output.

[0003] This planetary geared hub motor uses a built-in planetary gear reduction mechanism to convert the high speed and low torque of the motor into the low speed and high torque required by the wheel, thus allowing the motor to operate in a high-efficiency range and solving the problems of low torque density and large size and weight of direct-drive hub motors. Its main structure includes a high-speed inner rotor, a motor body, and an integrated planetary gear reducer. The planetary gear reducer includes a sun gear, planet gears, a planet carrier, and an internal gear ring. Power is transmitted to the sun gear via the motor output shaft, and after being reduced and increased in torque by the planetary gear system, it is output to the hub by the planet carrier.

[0004] Traditional planetary gear hub motors have the following disadvantages: 1. The connection strength between the planetary carrier and the output shaft is poor, especially in motor structures with a single-sided output shaft. The output shaft needs to withstand high torque and impact for a long time, making both prone to accidental breakage and causing hub eccentricity; 2. The strength of the planetary carrier and planetary gear shaft is low. The planetary carrier is prone to plastic deformation or even tearing, causing the sun gear, planetary gears, and internal gear ring to lose stable meshing, resulting in motor output failure; 3. Hub motors need to withstand complex alternating loads from the road surface. The low assembly strength between the motor shaft and the planetary carrier leads to a significant decrease in the fit accuracy between the motor shaft and the planetary carrier after prolonged use, disrupting the correct gear meshing clearance, causing increased vibration and noise, resulting in gear wear and reducing the overall service life of the machine. Utility Model Content

[0005] In view of the shortcomings of the existing technology, the purpose of this utility model is to provide a high-precision planetary gear hub motor, in which the output shaft and planetary carrier are integrated by aluminum alloy die casting process, which reduces weight while improving structural rigidity and precision.

[0006] To achieve the above objectives, the technical solution adopted by this utility model is as follows: a high-precision planetary geared hub motor, comprising a planetary stator assembly, an inner rotor assembly, and an outer rotor assembly. The planetary stator assembly includes an integral structure formed by die-casting aluminum alloy, comprising a planetary carrier and an output shaft. The planetary carrier includes a first-layer carrier and a second-layer carrier, with the first-layer carrier located outside the second-layer carrier. At least three integrally formed connecting columns are provided between the first-layer carrier and the second-layer carrier, with each connecting column spaced apart along the circumferential direction. Three planetary shafts are provided between the first-layer carrier and the second-layer carrier, each planetary shaft having a planetary gear rotatably mounted via a bearing. The output shaft is located on the axial position of the first side of the planetary carrier and extends along the axial direction to the outside of the motor. A stator sleeve is formed on the axial position of the second side of the planetary carrier, and a motor stator is fixedly mounted on the outside of the stator sleeve. The inner rotor assembly includes an inner rotor... The inner rotor housing and motor shaft are equipped with multiple strong magnets along the edge of the inner rotor housing. These strong magnets are evenly distributed along the circumference and are respectively engaged with the electromagnetic drive of the motor stator. A shaft sleeve is provided at the center of the inner rotor housing, and the inner rotor housing is fixedly fitted to the motor shaft through the shaft sleeve. The motor shaft is rotatably connected to the cavity of the stator sleeve. The first end of the motor shaft is equipped with a sun gear, which is located inside each planetary gear and meshes with each planetary gear. The outer rotor assembly includes a rotor housing and a rotor rear cover that are connected by a cover. An internal gear ring is formed on the inner side wall of the rotor housing, and the internal gear ring meshes with each planetary gear. A central sleeve hole is provided at the center of the rotor housing, and the central sleeve hole is rotatably fitted to the output shaft through another bearing. A centrally located mounting groove is formed on the inner side of the rotor rear cover, and a first support bearing is embedded in the mounting groove. The second end of the motor shaft is inserted into the inner ring of the first support bearing.

[0007] In a further technical solution, the stator sleeve cavity is provided with a second support bearing and a third support bearing overlapping along its axial direction, and a separator ring is sandwiched between the second support bearing and the third support bearing. The motor shaft is respectively inserted into the inner ring of the second support bearing and the third support bearing. A compression spring is fitted on the shaft sleeve, with one end of the compression spring contacting the inner side wall of the inner rotor housing and the other end contacting the inner ring of the second support bearing, so as to elastically press against the second support bearing and the third support bearing, thereby eliminating their axial clearance.

[0008] In a further technical solution, the outer wall of the outer end of the motor shaft is formed with an annular groove, and an O-ring is fitted inside the annular groove. The O-ring is sandwiched between the inner wall of the inner ring of the first support bearing to reduce noise.

[0009] In a further technical solution, the inside of the output shaft is hollowed out to form a core groove, and a wire outlet is opened on one side of the outer section of the output shaft, which connects to the core groove; the side of the planetary carrier is formed with a recessed wire groove, the outer end of which connects to the core groove and the inner end extends to the inner side of the second layer carrier; the inner side of the second layer carrier is provided with a control panel, which is connected to the motor stator. The control panel is connected to a host computer via a wire harness, and the wire harness passes through the wire groove, the core groove, and the wire outlet, respectively. The wire outlet is sealed with waterproof adhesive.

[0010] In a further technical solution, a wire baffle is fixed to the outer side of the first layer frame by bolts. The wire baffle spans the wire groove and presses against the limiting wire harness.

[0011] In a further technical solution, the rotor housing and the rotor rear cover are fastened together by bolts, and another O-ring is sandwiched between the mating surfaces of the two.

[0012] In a further technical solution, an oil seal is provided between the central sleeve hole of the rotor housing and the output shaft to improve the overall waterproof and dustproof performance of the machine.

[0013] In a further technical solution, the outer surface of the first shelf is formed with a reinforcing rib structure to improve the structural strength of the shelf.

[0014] The advantages of this invention compared to the prior art after adopting the above structure are: 1. The planetary carrier and output shaft in this utility model are integrally formed using an aluminum alloy die-casting process. This integrated design fundamentally eliminates the risks of loosening, stress concentration, and fatigue fracture that may occur when the planetary carrier and output shaft are connected by keys, bolts, or interference fits in traditional structures.

[0015] 2. The first and second layers of the planetary carrier, along with at least three integrally formed connecting columns, together form a high-rigidity frame structure that can effectively resist impact loads under high torque and complex road conditions, preventing plastic deformation or tearing of the planetary carrier. This ensures the long-term stability of the meshing transmission between the sun gear, planet gears, and internal gear ring, greatly improving the reliability and service life of the entire machine.

[0016] 3. By setting compression springs to elastically press against the second and third support bearings, the axial clearance of the bearings is effectively eliminated, avoiding axial movement and noise caused by the clearance.

[0017] 4. An O-ring seal is installed at the mating point between the motor shaft and the first support bearing. This seal absorbs minute vibrations and further reduces noise. This ensures the motor maintains high precision and stability even during high-speed operation and load variations, significantly reducing vibration and noise.

[0018] 5. The motor shaft and stator sleeve are supported by a second and a third support bearing. This support structure greatly enhances the rigidity of the motor rotor system, effectively resists radial forces and bending moments from the road surface, prevents shaft deformation, maintains the accuracy of gear meshing clearance over a long period of time, and avoids problems such as uneven wear and efficiency reduction caused by insufficient support rigidity. Attached Figure Description

[0019] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0020] Figure 1 This is a radial cross-sectional view of the present invention.

[0021] Figure 2 This is an axial cross-sectional view of the present invention.

[0022] Figure 3 This is a schematic diagram of the internal structure of this utility model.

[0023] Figure 4 This is a schematic diagram of the integral structure in this utility model. Detailed Implementation

[0024] The following are merely preferred embodiments of the present invention and do not limit the scope of protection of the present invention.

[0025] like Figures 1 to 4As shown, a high-precision planetary geared hub motor includes a planetary stator assembly, an inner rotor assembly, and an outer rotor assembly 1. The planetary stator assembly includes an integral structure 3 formed by die-casting aluminum alloy, comprising a planetary carrier 302 and an output shaft 301. The planetary carrier 302 includes a first carrier 321 and a second carrier 322. The first carrier 321 is located outside the second carrier 322. At least three integrally formed connecting posts 323 are provided between the first carrier 321 and the second carrier 322. Each connecting post 323 is along... Three planetary shafts 421 are spaced apart in a circumferential direction between the first layer 321 and the second layer 322. Each planetary shaft 421 is rotatably mounted with a planetary gear 42 via a bearing. The output shaft 301 is located on the axis of the first side of the planetary carrier 302 and extends to the outside of the motor along the axis. A stator sleeve 324 is formed on the axis of the second side of the planetary carrier 302, and a motor stator 325 is fixedly mounted on the outside of the stator sleeve 324. The inner rotor assembly includes an inner rotor housing 2 and a motor shaft. 21. Multiple strong magnets are provided on the edge of the inner rotor housing 2, and each strong magnet is evenly distributed along the circumference. Each strong magnet is electromagnetically driven by the motor stator 325. A shaft sleeve is provided at the center of the inner rotor housing 2, and the inner rotor housing 2 is fixedly sleeved to the motor shaft 21 through the shaft sleeve. The motor shaft 21 is rotatably connected to the cavity of the stator sleeve 324. The first end of the motor shaft 21 is equipped with a sun gear 41, which is located inside each planetary gear 42 and meshes with each planetary gear 42. Outer rotor assembly 1 The rotor housing 11 and rotor rear cover 12 are connected by a cover. The inner sidewall of the rotor housing 11 is formed with an internal gear ring 111, which is meshed with each planetary gear 42. The center of the rotor housing 11 is provided with a central sleeve hole, which is rotatably connected to the output shaft 301 through another bearing. The inner side of the rotor rear cover 12 is formed with a centrally located mounting groove 121, in which a first support bearing 31 is embedded and installed. The second end of the motor shaft 21 is inserted into the inner ring of the first support bearing 31.

[0026] In this embodiment, the connecting post 323 has a triangular cross-sectional shape, and there are three of them, located at the edges of the planet carrier 302.

[0027] The planetary carrier 302 and output shaft 301 in this invention are integrally formed using an aluminum alloy die-casting process. This integrated design fundamentally eliminates the risks of loosening, stress concentration, and fatigue fracture that may occur when the planetary carrier and output shaft are connected by keys, bolts, or interference fits in traditional structures.

[0028] Specifically, the stator sleeve 324 has a second support bearing 32 and a third support bearing 33 overlapping along its axial direction in its cavity. A separator ring 34 is sandwiched between the second support bearing 32 and the third support bearing 33. The motor shaft 21 is inserted into the inner rings of the second support bearing 32 and the third support bearing 33 respectively. A compression spring 22 is fitted on the shaft sleeve. One end of the compression spring 22 contacts the inner side wall of the inner rotor housing 2, and the other end contacts the inner ring of the second support bearing 32, so as to elastically press against the second support bearing 32 and the third support bearing 33, thereby eliminating their axial clearance.

[0029] By setting a compression spring 22 to press against the second and third support bearings, the axial clearance of the bearings is effectively eliminated, avoiding axial movement and noise caused by the clearance.

[0030] The motor shaft 21 and the stator sleeve 324 are supported by a second and a third support bearing. This support structure greatly enhances the rigidity of the motor rotor system, effectively resists radial forces and bending moments from the road surface, prevents shaft deformation, maintains the accuracy of gear meshing clearance over a long period of time, and avoids problems such as uneven wear and efficiency reduction caused by insufficient support rigidity.

[0031] Specifically, the outer wall of the outer end of the motor shaft 21 is formed with an annular groove 211, and an O-ring 122 is sleeved inside the annular groove 211. The O-ring 122 is sandwiched in the inner wall of the inner ring of the first support bearing 31 to reduce noise.

[0032] An O-ring 122 is installed at the mating point between the motor shaft 21 and the first support bearing 31. This absorbs minute vibrations and further reduces noise. This ensures that the motor maintains high precision and stability even during high-speed operation and load changes, significantly reducing vibration and noise.

[0033] Specifically, the output shaft 301 is hollowed out to form a core groove, and a cable outlet 310 is provided on one side of the outer section of the output shaft 301, which connects to the core groove; the planetary carrier 302 has a recessed cable groove 320 formed on its side, which is located on the outer side of one of the connecting posts 323; the outer end of the cable groove 320 connects to the core groove, and the inner end extends to the inner side of the second layer carrier 322; the inner side of the second layer carrier 322 is provided with a control panel 91, which is connected to the motor stator 325. The control panel 91 is connected to a host computer via a wiring harness 9, which passes through the cable groove 320, the core groove, and the cable outlet 310, and the cable outlet 310 is sealed with waterproof adhesive.

[0034] Specifically, a wire baffle 3201 is fixed to the outer side of the first layer rack 321 by bolts. The wire baffle 3201 spans the wire groove 320 and presses against the limiting wire harness 9.

[0035] Specifically, the rotor housing 11 and the rotor rear cover 12 are fastened together by bolts, and another O-ring 122 is sandwiched between the two covering surfaces.

[0036] Specifically, an oil seal 112 is provided between the central sleeve hole of the rotor housing 11 and the output shaft 301 to improve the waterproof and dustproof performance of the whole machine.

[0037] Specifically, the outer surface of the first shelf 321 is formed with a reinforcing rib structure 3211 to improve the structural strength of the shelf.

[0038] The above description is only a preferred embodiment of this utility model. For those skilled in the art, there will be changes in the specific implementation method and application scope based on the idea of ​​this utility model. The content of this specification should not be construed as a limitation of this utility model.

Claims

1. A high-precision planetary geared hub motor, comprising a planetary stator assembly, an inner rotor assembly, and an outer rotor assembly (1), characterized in that: The planetary stator assembly includes an integral structure (3) formed by die casting of aluminum alloy, comprising a planet carrier (302) and an output shaft (301). The planet carrier (302) includes a first carrier (321) and a second carrier (322). The first carrier (321) is located outside the second carrier (322). At least three integrally formed connecting posts (323) are provided between the first carrier (321) and the second carrier (322). The connecting posts (323) are spaced apart along the circumferential direction. Three planetary shafts (421) are provided between the first-layer frame (321) and the second-layer frame (322). Each planetary shaft (421) is rotatably mounted with a planetary gear (42) via a bearing. The output shaft (301) is located on the first side of the planetary carrier (302) and extends to the outside of the motor along the axial direction. A stator sleeve (324) is formed on the second side of the planetary carrier (302) at the axial position. A motor stator (325) is fixedly installed on the outside of the stator sleeve (324). The inner rotor assembly includes an inner rotor housing (2) and a motor shaft (21). The inner rotor housing (2) is provided with multiple strong magnets on its edge. Each strong magnet is evenly distributed along the circumference and is electromagnetically driven by the motor stator (325). A shaft sleeve is provided at the center of the inner rotor housing (2). The inner rotor housing (2) is fixedly sleeved to the motor shaft (21) through the shaft sleeve. The motor shaft (21) is rotatably connected to the cavity of the stator sleeve (324). The first end of the motor shaft (21) is equipped with a sun tooth (41). The sun tooth (41) is located inside each planetary gear (42) and meshes with each planetary gear (42). The outer rotor assembly (1) includes a rotor housing (11) and a rotor rear cover (12) that are connected together. The inner sidewall of the rotor housing (11) is formed with an internal gear ring (111), which is meshed with each planetary gear (42). The rotor housing (11) has a central sleeve hole at its center, which is rotatably connected to the output shaft (301) through another bearing. The inner side of the rotor rear cover (12) is formed with a centrally located mounting groove (121), in which a first support bearing (31) is embedded. The second end of the motor shaft (21) is inserted into the inner ring of the first support bearing (31).

2. The high-precision planetary geared hub motor according to claim 1, characterized in that: The stator sleeve (324) has a second support bearing (32) and a third support bearing (33) overlapping along its axial direction. A separator ring (34) is sandwiched between the second support bearing (32) and the third support bearing (33). The motor shaft (21) is inserted into the inner rings of the second support bearing (32) and the third support bearing (33) respectively. The shaft sleeve is fitted with a compression spring (22). One end of the compression spring (22) contacts the inner side wall of the inner rotor housing (2), and the other end contacts the inner ring of the second support bearing (32) to elastically press against the second support bearing (32) and the third support bearing (33), thereby eliminating their axial clearance.

3. A high-precision planetary geared hub motor according to claim 2, characterized in that: The outer wall of the outer end of the motor shaft (21) is formed with an annular groove (211), and an O-ring (122) is fitted inside the annular groove (211). The O-ring (122) is sandwiched in the inner wall of the inner ring of the first support bearing (31) to reduce noise.

4. A high-precision planetary geared hub motor according to claim 3, characterized in that: The output shaft (301) has its interior hollowed out to form a core groove. A wire outlet (310) is provided on one side of the outer section of the output shaft (301), and the wire outlet (310) is connected to the core groove. The planetary carrier (302) has a recessed wire groove (320) formed on its side. The outer end of the wire groove (320) is connected to the core groove, and the inner end extends to the inner side of the second layer carrier (322). The inner side of the second layer carrier (322) is provided with a control panel (91). The control panel (91) is connected to the motor stator (325). The control panel (91) is connected to the host computer through a wire harness (9). The wire harness (9) passes through the wire groove (320), the core groove, and the wire outlet (310). The outlet (310) is sealed with waterproof adhesive.

5. A high-precision planetary geared hub motor according to claim 4, characterized in that: A wire baffle (3201) is fixed to the outer side of the first shelf (321) by bolts. The wire baffle (3201) spans the wire groove (320) and presses against and limits the wire harness (9).

6. A high-precision planetary geared hub motor according to claim 1, characterized in that: The rotor housing (11) and the rotor rear cover (12) are fastened together by bolts, and another O-ring (122) is sandwiched between their mating surfaces.

7. A high-precision planetary geared hub motor according to claim 1, characterized in that: An oil seal (112) is provided between the central sleeve hole of the rotor housing (11) and the output shaft (301) to improve the waterproof and dustproof performance of the whole machine.

8. A high-precision planetary geared hub motor according to claim 1, characterized in that: The outer side of the first shelf (321) is formed with a reinforcing rib structure (3211) to improve the structural strength of the shelf.

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