Oil cooling structure of hub motor

Abstract

The utility model relates to an oil cooling structure of a hub motor, which comprises a stator, a rotor, a speed reducing mechanism, a motor driving shaft, a front end cover and a rear end cover, the rotor is positioned in the stator, the rotor is sleeved on the motor driving shaft and is connected with the motor driving shaft, and the motor driving shaft is arranged in the front end cover and the rear end cover in a liquid sealing and penetrating manner. The front end cover, the motor driving shaft and the rear end cover divide the internal space of the motor into an oil cavity and a power cavity, oil is injected into the oil cavity, the speed reducing mechanism is located in the oil cavity, and the stator and the rotor are located in the power cavity. The internal space of the motor is divided into the oil cavity and the power cavity, the speed reducing mechanism and all bearings in the motor are located in the oil cavity, oil in the oil cavity is cooled while achieving lubrication of gears and the bearings, the number of heating sources in contact with the oil is large, and the heat dissipation effect is good; the stator and the rotor are not in contact with oil, so that the oil is prevented from generating resistance to the rotor in the running process, and scrap iron powder generated by gear abrasion is also prevented from entering the stator and the rotor along with the oil.

Description

Technical Field

[0001] The utility model relates to an oil cooling structure of a hub motor and belongs to the technical field of hub motors. Background Art

[0002] At present, the oil cooling method of the hub motor is usually to immerse the motor rotor and stator to achieve heat dissipation. However, when the oil is immersed in the rotor, the oil will produce resistance to the rotor during operation, resulting in a decrease in motor performance. At the same time, if it is a hub reduction motor, the stator and rotor parts have no sealing structure. If the stator and rotor are cooled by oil, a large amount of iron filings and powder generated by gear wear during high-speed operation will enter the stator and rotor with the oil, causing the rotor magnet to absorb a large amount of iron filings and powder, causing the stator and rotor to sweep the bore (when the motor rotates, the phenomenon of the outer ring of the rotor rubbing against the inner circle of the stator is called stator and rotor sweeping the bore), and the movement structure is damaged.

[0003] Therefore, in the hub reduction motor, when the stator and rotor have no sealing structure, oil cooling cannot be used for heat conduction, and only traditional air convection can be used for heat dissipation, and the heat dissipation effect is poor. Utility Model Content

[0004] The utility model aims to provide an oil cooling structure of a hub motor for reducing the temperature of a reduction mechanism by means of oil and preventing a stator and a rotor from contacting the oil in view of the shortcomings of the prior art.

[0005] To achieve the purpose, the technical solution adopted by the utility model is:

[0006] The oil cooling structure of the hub motor includes a stator, a rotor, a reduction mechanism, a motor driving shaft, a front cover and a rear cover, wherein the rotor is located in the stator, the rotor is sleeved on the motor driving shaft and connected to the motor driving shaft, the motor driving shaft is liquid-sealed and penetrated in the front cover and the rear cover, the front cover, the motor driving shaft and the rear cover divide the internal space of the motor into an oil chamber and a power chamber, oil is injected into the oil chamber, the reduction mechanism is located in the oil chamber, and the stator and rotor are located in the power chamber.

[0007] As a further optimization of the above technical solution: it also includes a motor output shaft, a rim, a wheel hub and several bearings, several of the bearings are located in the oil chamber, the front end cover and the rear end cover are respectively located on both sides of the wheel hub, the stator is located in the wheel hub, the motor driving shaft is transmission-connected to the motor output shaft through the reduction mechanism, the motor output shaft is fixed to the wheel rim, after power is turned on, the stator drives the rotor to rotate, the rotor drives the motor driving shaft to rotate, the motor driving shaft reduces power through the reduction mechanism and outputs it to the motor output shaft, and the motor output shaft drives the wheel rim to rotate.

[0008] As a further optimization of the above technical solution: the reduction mechanism is a planetary gear structure, the reduction mechanism includes a sun gear, the sun gear is sleeved on the motor output shaft and can rotate relative to the motor output shaft, a connecting shaft is provided in the middle of the sun gear, the motor driving shaft is sleeved on the connecting shaft and is positioned and connected to the connecting shaft through a flat key.

[0009] As a further optimization of the above technical solution: a locating bearing for axially positioning the sun gear is also sleeved on the motor output shaft, the locating bearing is a planar thrust bearing, a second locating step is provided on the inner circumference of the locating bearing, a third locating step is formed on the motor output shaft, and the second locating step is in contact with the third locating step.

[0010] As a further optimization of the above technical solution: the inner circumferential surface of the front end cover extends toward the direction of the rear end cover to form an end cover protrusion, the motor driving shaft liquid seal is penetrated in the end cover protrusion, a driving shaft hole is formed in the end cover protrusion, the motor driving shaft is penetrated in the driving shaft hole, a first rotating sealing mechanism is provided between the motor driving shaft and the wall of the driving shaft hole, and the first rotating sealing mechanism includes a first bearing and a first oil seal sleeved on the motor driving shaft.

[0011] As a further optimization of the above technical solution: an oil seal seat is installed on the side of the front end cover, the motor output shaft is inserted into the oil seal seat, a second rotary sealing mechanism is provided between the motor output shaft and the oil seal seat, and the second rotary sealing mechanism includes a second oil seal and a second bearing sleeved on the motor output shaft.

[0012] As a further optimization of the above technical solution: the oil chamber includes a first oil chamber, the first oil chamber includes the space between the inner circumference of the front end cover and the motor driving shaft, and the space between the inner circumference of the oil seal seat and the motor output shaft, the first oil chamber is sealed by the second oil seal and the first oil seal, the reduction mechanism is located in the first oil chamber, and the second bearing, the first bearing, and the positioning bearing are also located in the first oil chamber.

[0013] As a further optimization of the above technical solution: a first insert ring is formed on the oil seal seat, a second installation groove is formed on the first insert ring, a sealing ring is arranged in the second installation groove, the first insert ring is inserted into the front end cover, and the sealing ring seals the first insert ring with the inner wall of the front end cover.

[0014] As a further optimization of the above technical solution: a first oil seal anti-retraction groove is formed on the hole wall of the active shaft hole, the first oil seal anti-retraction groove is located on the outside of the outer peripheral surface of the first oil seal and adjusts the air pressure, a positioning structure is also provided between the motor active shaft and the active shaft hole, the positioning structure is in contact with the first oil seal and positions the installation of the first oil seal, the positioning structure includes a first retaining ring sleeved on the motor active shaft, a first retaining ring groove is also formed on the hole wall of the active shaft hole, the first retaining ring is located in the first retaining ring groove, the first retaining ring is in contact with the first oil seal, a first stop block protruding inward is formed on the end of the hole wall of the active shaft hole, the two side surfaces of the first bearing are respectively in contact with the first stop block and the first retaining ring, a first installation groove is also formed on the motor active shaft, a first rubber ring is provided in the first installation groove, and the first rubber ring is located on the inner side of the first bearing.

[0015] As a further optimization of the above technical solution: the second rotating sealing mechanism includes a second oil seal, a second bearing and a second rubber ring sleeved on the motor output shaft, a second block and a second oil seal back-stop groove are formed on the inner wall of the oil seal seat, the second block is located between the second oil seal and the second bearing, the second oil seal and the second bearing are both in contact with the second block, a third block is also formed on the motor output shaft, the second bearing is in contact with the third block, the second oil seal back-stop groove is located on the outside of the outer peripheral surface of the second oil seal, and the second rubber ring is located on the inside of the second bearing.

[0016] As a further optimization of the above technical solution: a bearing seat is installed on the rear end cover, a second insert ring is formed on the bearing seat, the second insert ring is inserted into the motor driving shaft, a disc brake seat is provided outside the bearing seat, a third insert ring is formed on the disc brake seat, the third insert ring is inserted into the bearing seat, the end of the motor output shaft is inserted into the bearing seat and the disc brake seat, a fourth rotating sealing mechanism is provided between the motor output shaft and the inner wall of the bearing seat, and the fourth rotating sealing mechanism includes a fourth bearing sleeved on the motor output shaft , O-ring bushing and sealing O-ring, the fourth rotary sealing mechanism also includes a fourth oil seal and a third retaining ring sleeved on the third insert ring, the inner wall of the third insert ring is provided with a fifth positioning step, the inner circumference of the third insert ring is in close contact with the O-ring bushing, the sealing O-ring is located between the O-ring bushing and the fifth positioning step, the inner wall of the bearing seat is also provided with a fifth stopper and a third retaining ring groove, the third retaining ring is located in the third retaining ring groove, and the two side surfaces of the fourth oil seal are respectively in contact with the fifth stopper and the third retaining ring.

[0017] As a further optimization of the above technical solution: a first oil-passing gap is formed between the inner wall of the sun tooth and the motor output shaft, the oil chamber also includes a second oil chamber, the second oil chamber includes the space between the inner circumferential surface of the motor driving shaft and the motor output shaft, and the space between the inner circumferential surface of the bearing seat and the motor output shaft, the second oil chamber is connected to the first oil chamber through the first oil-passing gap, the second oil chamber is sealed by the fourth oil seal, and the fourth bearing is located in the second oil chamber.

[0018] As a further optimization of the above technical solution: a third rotating sealing mechanism is provided between the motor driving shaft and the inner wall of the rear end cover, the third rotating sealing mechanism includes a third oil seal, a second retaining ring, a third bearing and a third rubber ring sleeved on the motor driving shaft, the inner wall of the rear end cover is provided with a second retaining ring groove and a third oil seal stop groove, the second retaining ring is located in the second retaining ring groove, the inner wall of the rear end cover is also provided with a protruding fourth stop block, the motor driving shaft is provided with a fourth positioning step, the two side surfaces of the third bearing are respectively in contact with the fourth stop block and the fourth positioning step, the third oil seal stop groove is located on the outer side of the outer peripheral surface of the third oil seal, and the third rubber ring is located on the inner side of the third bearing.

[0019] As a further optimization of the above technical solution: a second oil gap is formed between the outer wall of the second insert ring and the inner wall of the motor driving shaft, the oil chamber includes a third oil chamber, the third oil chamber includes the space between the inner circumferential surface of the rear end cover and the motor driving shaft, the third oil chamber is connected with the second oil chamber through the second oil gap, the third oil chamber is sealed by the third oil seal, and the third bearing is located in the third oil chamber.

[0020] As a further optimization of the above technical solution: the front end cover is provided with an oil inlet hole and an oil drain hole connected to the first oil chamber, the oil flows into the first oil chamber from the oil inlet hole, the screws and gaskets seal the oil inlet hole and the oil drain hole, the motor starts to rotate, the oil flows in the rotating motor and enters the second oil chamber and the third oil chamber, lubricates and cools the reduction mechanism, the first bearing, the second bearing, the third bearing, the fourth bearing, and the positioning bearing, and the oil drain hole is used to discharge the oil.

[0021] As a further optimization of the above technical solution: the reduction mechanism also includes a ring gear, a planetary bracket and a plurality of planetary gears, the plurality of planetary gears are meshed with the sun gears, the planetary gears are meshed with the inner circumference of the ring gear, the outer circumference of the ring gear and the front end cover are positioned and connected by a flat key, a planetary gear shaft is provided in the middle of the planetary gear, the two ends of the planetary gear shaft are respectively fixed on the planetary bracket and the motor output shaft, the motor driving shaft drives the sun gear to rotate, the sun gear drives the planetary gear to rotate, and the planetary gears transmit power to the motor output shaft.

[0022] Compared with the prior art, the utility model divides the internal space of the motor into an oil chamber and a power chamber, the reduction mechanism and all the bearings in the motor are located in the oil chamber, the oil in the oil chamber cools down while achieving lubrication of the gears and bearings, the oil contacts many heat sources, and the heat dissipation effect is good; the stator and the rotor are located in the power chamber, the stator and the rotor do not contact the oil, so as to prevent the oil from generating resistance to the rotor during operation, and also prevent the iron filings powder generated by gear wear from entering the stator and rotor with the oil, avoiding the phenomenon of stator and rotor sweeping, and protecting the power structure of the motor; the oil chamber, the power chamber, and the external environment are sealed by the second oil seal, the first oil seal, the fourth oil seal, and the third oil seal, so as to have a good sealing effect and prevent oil leakage. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a schematic diagram of the exploded structure of a hub reduction motor.

[0024] Figure 2 It is a schematic diagram of the cross-sectional structure of a hub reduction motor.

[0025] Figure 3 yes Figure 2 Schematic diagram of the enlarged structure at point A in the middle.

[0026] Figure 4 yes Figure 2 Schematic diagram of the enlarged structure at point B in the middle.

[0027] Figure 5 It is another cross-sectional structural schematic diagram of a hub reduction motor.

[0028] Figure 6 It is a schematic diagram of the exploded structure of the rotor in a hub reduction motor. DETAILED DESCRIPTION

[0029] The present invention will be further described below in conjunction with the accompanying drawings and specific implementations. Figure 1-6As shown, a hub reduction motor includes a power source, a motor driving shaft 3, a reduction mechanism 4, a motor output shaft 5, and a rim 6. The motor driving shaft 3 is connected to the motor output shaft 5 through the reduction mechanism 4, and the rim 6 is fixed to the end of the motor output shaft 5. The power source drives the motor driving shaft 3 to rotate, and the motor driving shaft 3 reduces the power output to the motor output shaft 5 through the reduction mechanism 4, so that the motor output shaft 5 drives the rim 6 to rotate. The power source includes a stator 1 and a rotor 2, and the rotor 2 is located in the stator 1. The rotor 2 is sleeved on the motor driving shaft 3 and connected to the motor driving shaft 3. After power is turned on, the stator 1 drives the rotor 2 to rotate, and the rotor 2 drives the motor driving shaft 3 to rotate.

[0030] In the above technical solution: a fixing block 61 is provided on the side of the rim 6, and the fixing block 61 and the rim 6 are connected by a connecting bridge 62. A plurality of fixing bolts 63 are provided on the fixing block 61, and the ends of the fixing bolts 63 are fixed to the ends of the motor output shaft 5, so that the rim 6 is directly fixed to the ends of the motor output shaft 5. When replacing a tire, the motor does not need to be disassembled, and the tire can be easily replaced by only loosening the fixing bolts 63 and removing the rim 6 from the motor output shaft 5.

[0031] The above technical solution also includes a wheel hub 7 , a front end cover 8 and a rear end cover 9 . The wheel hub 7 is located inside the wheel rim 6 , the stator 1 is located inside the wheel hub 7 , and the front end cover 8 and the rear end cover 9 are located on both sides of the wheel hub 7 , respectively.

[0032] In the above technical solution: a coil is wound on the stator 1. The rotor 2 includes a rotor support 21, a rotor steel sheet 23 and a plurality of magnets 22. The rotor steel sheet 23 is sleeved on the rotor support 21. A plurality of mounting protrusions 24 are provided on the rotor steel sheet 23, and mounting channels 25 are formed in the mounting protrusions 24. A separation groove 26 is provided between two adjacent mounting protrusions 24. The magnets 22 are located in the mounting channels 25, and two magnets 22 are provided in each mounting channel 25. The magnets 22 are arc-shaped, and the width of the two magnets 22 in the mounting channel 25 is b. The reason why a whole arc-shaped magnetic steel is not directly set in the installation channel 25 is that: if an arc-shaped magnetic steel is set in the installation channel 25, the width of the arc-shaped magnetic steel is 2b, that is, the width of the arc-shaped magnetic steel is wider and the curvature is larger; at the same time, the arc-shaped magnetic steel is produced by cutting it from the square raw material through wire cutting. After cutting the arc-shaped magnetic steel, the remaining part of the square raw material that cannot be cut into a complete arc-shaped magnetic steel is wasted, and the wider the width of the arc-shaped magnetic steel and the larger the curvature, the lower the utilization rate of the square raw material, the more raw materials are wasted, the price of the magnetic steel raw materials is high, and the cost is wasted. Therefore, two magnetic steels 22 are set in the installation channel 25. The magnetic steels 22 have a small width and a small curvature, which can make the utilization rate of the square raw material higher, greatly reduce the waste of raw materials, and save costs.

[0033] The setting of the separation slot 26 makes the pole arc coefficient of the motor less than 1, reduces the amount of magnetic steel 22 used, and reduces costs. At the same time, the separation slot 26 also makes the cross-axis inductance of the motor greater than the direct-axis inductance, and the salient pole rate of the motor greater than 1, so that the motor has a salient pole effect. The salient pole effect increases the reluctance torque of the torque output by the motor, that is, it can output a larger torque under the same phase current, making the vehicle more powerful and the starting acceleration performance more superior. In addition, the salient pole effect can also enhance the weak magnetic speed-up effect, thereby obtaining a higher speed and a larger speed-up space, which can meet the driving requirements of electric vehicles, achieve a balance between cruising range and power, and improve the overall performance of the motor. That is, it is achieved by reducing the amount of magnetic steel 22 used while ensuring that the performance parameters of the motor remain unchanged, thereby greatly reducing costs.

[0034] In the above technical solution: a first magnetic steel retaining ring 28 is integrally formed at the end of the outer circumference of the rotor bracket 21, and the rotor steel sheet 23 is sleeved on the outer circumference of the rotor bracket 21, and the side of the rotor steel sheet 23 is in contact with the first magnetic steel retaining ring 28; then the magnetic steel 22 is installed in the installation channel 25, so that the magnetic steel 22 is in contact with the first magnetic steel retaining ring 28. A second magnetic steel retaining ring 27 is sleeved on the outer circumference of the rotor bracket 21, and a plurality of screws 29 are provided on the second magnetic steel retaining ring 27, and the ends of the screws 29 pass through the rotor steel sheet 23 and are fixed on the rotor bracket 21. After installation, the first magnetic steel retaining ring 28 and the second magnetic steel retaining ring 27 are respectively located on both sides of the installation channel 25, and the side of the magnetic steel 22 is in contact with the first magnetic steel retaining ring 28 and the second magnetic steel retaining ring 27. Therefore, when the magnetic steel 22 and the second magnetic steel retaining ring 27 are installed in sequence, the axial movement of the magnetic steel 22 is positioned by the first magnetic steel retaining ring 28 and the second magnetic steel retaining ring 27, and the radial movement of the magnetic steel 22 is positioned by the inner wall of the installation channel 25, and the installation of the magnetic steel 22 can be achieved without glue, and the magnetic steel 22 is firmly installed, which greatly reduces the risk of the magnetic steel falling off, and ensures the reliability of the rotor. At the same time, the magnetic steel 22 is not easy to be damaged, and the rotor steel sheet 23 is not easy to deform. The second magnetic steel retaining ring 27 can be used as a dynamic balancing plate, and can achieve the purpose of stable operation of the motor by changing the mass distribution of the rotor 2.

[0035] In the above technical solution: the rotor steel sheet 23 is located in the stator 1, and the motor driving shaft 3 is connected to the rotor bracket 21; the stator 1 drives the rotor steel sheet 23, the magnetic steel 22, and the rotor bracket 21 to rotate, and the rotor bracket 21 drives the motor driving shaft 3 to rotate. The inner circumference of the rotor bracket 21 and the motor driving shaft 3 are positioned and connected by a flat key. The motor driving shaft 3 is also knurled, and the knurling is used to have an interference fit with the inner circumference of the rotor bracket 21, and then the motor driving shaft 3 and the rotor bracket 21 are tightly fitted by a press.

[0036] In the above technical solution: the reduction mechanism 4 is specifically a planetary gear structure, and the reduction mechanism 4 includes a ring gear 44, a planetary support 43, a sun gear 41 and a plurality of planetary gears 42. The sun gear 41 is sleeved on the motor output shaft 5 and can rotate relative to the motor output shaft 5. A connecting shaft 46 is provided in the middle of the sun gear 41, and the motor driving shaft 3 is sleeved on the connecting shaft 46 and is positioned and connected with the connecting shaft through a flat key, and a plurality of planetary gears 42 are meshed with the sun gear 41. The planetary gear 42 is meshed with the inner circumference of the ring gear 44, and the outer circumference of the ring gear 44 is positioned and connected with the front end cover 8 through a flat key. A planetary gear shaft 45 is provided in the middle of the planetary gear 42, and the two ends of the planetary gear shaft 45 are respectively fixed on the planetary support 43 and the motor output shaft 5, so that the planetary support 43, the motor output shaft 5 and the planetary gear 42 are fixed. The ring gear 44, the sun gear 41 and the planetary gear 42 are all helical gear structures to improve the stability of the work. The motor driving shaft 3 drives the sun gear 41 to rotate, and the sun gear 41 drives the planetary gear 42 to rotate, and the planetary gear 42 transmits power to the motor output shaft 5. When the motor is driven at high speed, the planetary gear 42 provides a larger reduction transmission ratio to achieve the reduction transmission between the motor driving shaft 3 and the motor output shaft 5, thereby improving the power density and output torque of the hub motor, making the motor have a higher speed and a higher power density; at the same time, the planetary gear reduction mechanism occupies a small axial space, and installing the reduction mechanism 4 on the motor output shaft 5 can compress the axial space of the motor and reduce the size of the motor. In this embodiment, there are three planetary gears 42. The rotor 2 and the sun gear 41 are not directly driven, but are driven through the motor driving shaft 3, which makes assembly more convenient and saves the material of the sun gear 41, thereby saving costs.

[0037] In the above technical solution: the inner circumference of the front end cover 8 extends toward the rear end cover 9 to form an end cover protrusion 81. A driving shaft hole 83 is formed in the end cover protrusion 81, and the motor driving shaft 3 is inserted into the driving shaft hole 83. A first rotary sealing mechanism is provided between the motor driving shaft 3 and the hole wall of the driving shaft hole 83. The first rotary sealing mechanism includes a first bearing 31 and a first oil seal 33 which are sequentially sleeved on the motor driving shaft 3. The first oil seal 33 seals the motor driving shaft 3 and the driving shaft hole 83. A first oil seal stop groove 86 is formed on the hole wall of the driving shaft hole 83. The first oil seal stop groove 86 is located outside the outer peripheral surface of the first oil seal 33 and plays a role in regulating air pressure. When the first oil seal 33 is installed, the excessive air pressure inside the motor will pop out the first oil seal 33. If a first oil seal stop groove 86 that can adjust the air pressure is provided, when the air pressure inside the motor is too high, the first oil seal stop groove 86 plays a role of buffering and regulation, so that the air pressure inside and outside the motor is more balanced, preventing the first oil seal 33 from popping out due to excessive air pressure, and ensuring the stable installation of the first oil seal 33. A positioning structure is also provided between the motor driving shaft 3 and the driving shaft hole 83. The positioning structure contacts the first oil seal 33 and positions the installation of the first oil seal 33. The positioning structure includes a first retaining ring 32 sleeved on the motor driving shaft 3. A first retaining ring groove is also formed on the hole wall of the driving shaft hole 83. The first retaining ring 32 is located in the first retaining ring groove, and the first retaining ring 32 contacts the first oil seal 33. The positioning structure may further include a positioning stopper. The hole wall of the driving shaft hole 83 protrudes inward to form the positioning stopper. The positioning stopper contacts the first oil seal 33 . The positioning stopper and the first retaining ring 32 are respectively located on both sides of the first oil seal 33 .

[0038] In the above technical solution: the end of the wall of the driving shaft hole 83 is formed with a first stopper 84 protruding inward. The two side surfaces of the first bearing 31 are in contact with the first stopper 84 and the first retaining ring 32 respectively. The motor driving shaft 3 is also formed with a first mounting groove, and a first rubber ring 34 is arranged in the first mounting groove. The first rubber ring 34 is located on the inner side of the first bearing 31 to prevent the inner circumference of the first bearing 31 from slipping relative to the motor driving shaft 3.

[0039] In the above technical solution: the side of the end cover protrusion 81 is bent to form a first positioning step 82, the speed reduction mechanism 4 is located in the end cover protrusion 81, and the first positioning step 82 positions the installation of the gear ring 44. The end cover protrusion 81 is used as a gear box body to install the speed reduction mechanism 4, so that the gear box body and the front end cover 8 are formed in one piece. The sun gear 41 is sleeved on the motor output shaft 5, and the motor output shaft 5 is also sleeved with a positioning bearing 51 for axial positioning of the sun gear 41, and the positioning bearing 51 is specifically a plane thrust bearing. The diameters of the two ends of the inner circumference of the positioning bearing 51 are different, so that the inner circumference of the positioning bearing 51 forms a second positioning step 52. At the same time, a third positioning step is formed on the motor output shaft 5, and the second positioning step 52 contacts the third positioning step to position the installation of the positioning bearing 51.

[0040] In the above technical solution: an oil seal seat 87 is installed on the side of the front end cover 8, a first insert ring 88 is formed on the oil seal seat 87, a second installation groove is formed on the first insert ring 88, a sealing ring 89 is arranged in the second installation groove, the first insert ring 88 is inserted into the front end cover 8, and the sealing ring 89 seals the first insert ring 88 with the inner circumference of the front end cover 8. The motor output shaft 5 is inserted into the oil seal seat 87, and a second rotary sealing mechanism is arranged between the motor output shaft 5 and the oil seal seat 87. The second rotary sealing mechanism includes a second oil seal 54, a second bearing 55 and a second rubber ring sleeved on the motor output shaft 5. A second stopper and a second oil seal stop groove are formed on the inner wall of the oil seal seat 87. The second stopper is located between the second oil seal 54 and the second bearing 55, and the second oil seal 54 and the second bearing 55 are both in contact with the second stopper. A third stopper 56 is also formed on the motor output shaft 5, and the second bearing 55 is in contact with the third stopper 56, and the third stopper 56 positions the installation of the second bearing 55. The second oil seal stop groove is located outside the outer circumference of the second oil seal 54, and the second oil seal stop groove prevents the excessive air pressure inside the motor from ejecting the second oil seal 54. The second rubber ring is located inside the second bearing 55 to prevent the inner circumference of the second bearing 55 from slipping relative to the motor output shaft 5.

[0041] In the above technical solution: the end of the motor driving shaft 3 is inserted into the rear end cover 9, and a third rotary sealing mechanism is provided between the motor driving shaft 3 and the inner wall of the rear end cover 9. The third rotary sealing mechanism includes a third oil seal 35, a second retaining ring 36, a third bearing 37 and a third rubber ring 39 sleeved on the motor driving shaft 3. The inner wall of the rear end cover 9 is provided with a second retaining ring groove and a third oil seal stop groove 96, and the second retaining ring 36 is located in the second retaining ring groove. The inner wall of the rear end cover 9 is also provided with a protruding fourth stop block 92, and the motor driving shaft 3 is provided with a fourth positioning step 310. The fourth stop block 92 and the fourth positioning step 310 are respectively located on both sides of the third bearing 37, and position the installation of the third bearing 37. The third oil seal stop groove 96 is located on the outer side of the outer circumference of the third oil seal 35, and the third oil seal stop groove 96 prevents the excessive air pressure inside the motor from ejecting the third oil seal 35. The third rubber ring 39 is located on the inner side of the third bearing 37 to prevent the inner circumference of the third bearing 37 from slipping relative to the motor driving shaft 3.

[0042] In the above technical solution: a bearing seat 91 is installed on the rear end cover 9, and a second insert ring 93 is formed on the bearing seat 91, and the second insert ring 93 is inserted into the motor driving shaft 3. A disc brake seat 10 is provided outside the bearing seat 91, and a third insert ring 101 is formed on the disc brake seat 10, and the third insert ring 101 is inserted into the bearing seat 91. The end of the motor output shaft 5 is inserted into the bearing seat 91 and the disc brake seat 10, and a fourth rotary sealing mechanism is provided between the motor output shaft 5 and the inner wall of the bearing seat 91. The fourth rotary sealing mechanism includes a fourth bearing 57, an O-ring bushing 58 and a sealing O-ring 53 sleeved on the motor output shaft 5, and the fourth rotary sealing mechanism also includes a fourth oil seal 59 and a third retaining ring 510 sleeved on the third insert ring 101. The inner wall of the third insert ring 101 is provided with a fifth positioning step, the inner circumference of the third insert ring 101 is in close contact with the O-ring bushing 58, the sealing O-ring 53 is located between the O-ring bushing 58 and the fifth positioning step, and the sealing O-ring 53 seals the installation between the motor output shaft 5 and the disc brake seat 10. The outer circumference of the fourth bearing 57 and the outer circumference of the fourth oil seal 59 are in close contact with the inner wall of the bearing seat 91. The inner wall of the bearing seat 91 is also provided with a fifth stopper 95 and a third stopper groove, the third stopper 510 is located in the third stopper groove, and the two side surfaces of the fourth oil seal 59 are in contact with the fifth stopper 95 and the third stopper 510 respectively.

[0043] In the above technical solution: the motor driving shaft 3 is liquid-tightly penetrated in the front cover 8 and the rear cover 9 through the second oil seal 54 and the third bearing 37, and the front cover 8, the motor driving shaft 3 and the rear cover 9 divide the internal space of the motor into an oil chamber and a power chamber. Specifically, the motor driving shaft 3 is liquid-tightly penetrated in the end cover protrusion 81, and the end cover protrusion 81, the motor driving shaft 3 and the rear cover 9 divide the internal space of the motor into an oil chamber and a power chamber. Oil is injected into the oil chamber, the speed reduction mechanism 4 is located in the oil chamber, and the stator 1 and the rotor 2 are located in the power chamber.

[0044] In the above technical solution: a first oil-passing gap 516 is formed between the inner circumference of the sun gear 41 and the motor output shaft 5. A second oil-passing gap 94 is formed between the outer wall of the second insert ring 93 and the inner wall of the motor driving shaft 3. The oil chamber includes a first oil chamber, a second oil chamber, and a third oil chamber. The first oil chamber includes the space between the inner circumference of the front end cover 8 and the motor driving shaft 3, and the space between the inner circumference of the oil seal seat 87 and the motor output shaft 5. The first oil chamber is sealed by the second oil seal 54 and the first oil seal 33. The speed reduction mechanism 4 is located in the first oil chamber, and the second bearing 55, the first bearing 31, and the positioning bearing 51 are also located in the first oil chamber;

[0045] The second oil chamber includes the space between the inner circumference of the motor driving shaft 3 and the motor output shaft 5, and the space between the inner circumference of the bearing seat 91 and the motor output shaft 5. The second oil chamber is connected with the first oil chamber through the first oil gap 516. The second oil chamber is sealed by the fourth oil seal 59. The fourth bearing 57 is located in the second oil chamber.

[0046] The third oil chamber includes the space between the inner circumference of the rear end cover 9 and the motor driving shaft 3. The third oil chamber is connected to the second oil chamber through the second oil gap 94. The third oil chamber is sealed by the third oil seal 35. The third bearing 37 is located in the third oil chamber.

[0047] The front cover 8 is provided with an oil inlet hole 812 and an oil drain hole 813 connected to the first oil chamber. The oil flows into the first oil chamber from the oil inlet hole 812. The screws and gaskets seal the oil inlet hole 812 and the oil drain hole 813. When the motor starts to rotate, the oil flows in the rotating motor and enters the second oil chamber and the third oil chamber to lubricate and cool the reduction mechanism 4, the first bearing 31, the second bearing 55, the third bearing 37, the fourth bearing 57, and the positioning bearing 51. The oil drain hole 813 is used to discharge the oil. The front cover 8 is also provided with an exhaust valve 814. After the temperature inside the motor rises, the gas is discharged through the exhaust valve 814. Since the speed reduction mechanism and bearings often generate severe heat when the motor is running, cooling the speed reduction mechanism and bearings is particularly important in the motor. In the utility model, the speed reduction mechanism 4 and all the bearings in the motor (the first bearing 31, the second bearing 55, the third bearing 37, the fourth bearing 57, and the positioning bearing 51 are collectively referred to as bearings) are located in the oil chamber. The oil in the oil chamber cools down the gears and bearings while achieving lubrication. The oil contacts many heat sources and has a good heat dissipation effect. In addition, the oil chamber and the power chamber are separated from each other, and the stator and the rotor do not contact the oil, which prevents the oil from generating resistance to the rotor during operation, and also prevents iron filings and powder generated by gear wear from entering the stator and rotor with the oil, thereby avoiding the phenomenon of stator and rotor sweeping and protecting the power structure of the motor.

[0048] In the above technical solution: a cooling channel 511 is formed through the motor output shaft 5, an output positioning block 512 is formed at one end of the motor output shaft 5, the output positioning block 512 is arranged in the oil seal seat 87, the output positioning block 512 and the oil seal seat 87 are connected by a second rotary sealing mechanism, and the rim 6 is fixed to the end of the output positioning block 512 by a fixing bolt 63. A receiving chamber 513 connected to the cooling channel 511 is formed in the output positioning block 512, the inner wall of the receiving chamber 513 is bent to form a sixth positioning step, a fan 514 is fixed in the receiving chamber 513, and the side of the fan 514 contacts the sixth positioning step. A guide slope 515 is formed at the end of the inner wall of the cooling channel 511, and the guide slope 515 forms a bell mouth at the end where the cooling channel 511 and the receiving chamber 513 are connected. When the motor output shaft 5 rotates, the fan 514 is driven to rotate synchronously. When the fan 514 rotates, wind is generated. The wind enters the cooling channel 511 through the bell mouth, and quickly takes away the heat of the motor output shaft 5, thereby realizing rapid heat dissipation and cooling of the motor output shaft 5. At the same time, the motor output shaft 5 can also take away the heat of objects in contact with it. For example, the outer wall of the motor output shaft 5 is in contact with the oil cavity. The wind in the cooling channel 511 can take away the heat of the oil in the oil cavity through the motor output shaft 5, and cool the oil in the oil cavity, so that the cooling effect of the oil in the oil cavity is better, the temperature rises more slowly, and rapid heat dissipation is realized, thereby improving the efficiency of the motor and increasing the service life of the motor.

[0049] In the above technical solution: a water cooling structure is provided on the wheel hub 7, the front cover 8 and the rear cover 9, and the water cooling structure includes a plurality of wheel hub waterways 71 located on the wheel hub 7, and guide grooves 85 located on the front cover 8 and the rear cover 9. The plurality of wheel hub waterways 71 are arranged parallel to the axis of the wheel hub 7 and are evenly distributed in a ring shape, and the guide grooves 85 are connected with two adjacent wheel hub waterways 71. The guide grooves 85 on the front cover 8 and the guide grooves on the rear cover 9 are arranged in staggered rows. A water inlet joint 97 and a water outlet joint 98 are provided on the rear cover 9, and the water inlet joint 97 and the water outlet joint 98 are respectively connected with two adjacent wheel hub waterways 71. The cooling water flows in from the water inlet joint 97, enters a guide groove 85 in the front end cover 8 through one of the hub water channels 71, and then enters a guide groove in the rear end cover 9 through the hub water channel 71 adjacent to the previous hub water channel 71, and so on, and finally flows through the last hub water channel 71 and is discharged from the water outlet joint 98, completing the cooling process of the motor housing and quickly taking away the heat of the coil on the stator.

[0050] The utility model combines oil cooling, air cooling and water cooling structures to achieve rapid heat dissipation, thereby improving the efficiency of the motor and increasing the service life of the motor. Oil cooling is the oil in the sealed oil chamber that lubricates and cools the speed reduction mechanism 4 and all the bearings in the motor. Air cooling is the rotation of the fan 514 in the motor output shaft 5, and the wind enters the cooling channel 511 through the bell mouth, quickly taking away the heat of the motor output shaft 5, and achieving rapid heat dissipation and cooling of the motor output shaft 5. At the same time, the outer wall of the motor output shaft 5 is in contact with the oil chamber, and the wind in the cooling channel 511 can take away the heat of the oil in the oil chamber through the motor output shaft 5, cool the oil in the oil chamber, and make the cooling effect of the oil in the oil chamber better and the temperature rise slower. Water cooling is the multiple hub water channels 71 on the hub 7, and the guide grooves 85 located on the front cover 8 and the rear cover 9. The cooling water flows through the guide grooves 85 and the hub water channel 71 to cool the motor housing part and quickly take away the heat of the coil on the stator. The combination of oil cooling, air cooling and water cooling structures can effectively cool down multiple heat sources when the motor is running, ensuring the normal operation of the motor.

[0051] In the above technical solution: a plurality of frame connection lugs 99 are arranged on the rear end cover 9, which are suitable for two-wheel single drive, three-wheel two-wheel drive or four-wheel suspension two-wheel drive or four-wheel drive.

[0052] The preferred specific embodiments of the present utility model are described in detail above. It should be understood that ordinary technicians in this field can make many modifications and changes based on the concept of the present utility model without creative work. Therefore, all technical solutions that can be obtained by technicians in this technical field based on the concept of the present utility model through logical analysis, reasoning or limited experiments on the basis of the existing technology should fall within the protection scope of the present utility model.

Claims

1. The oil cooling structure of the hub motor is characterized by The invention comprises a stator (1), a rotor (2), a speed reducing mechanism (4), a motor driving shaft (3), a front end cover (8) and a rear end cover (9), wherein the rotor (2) is located in the stator (1), the rotor (2) is sleeved on the motor driving shaft (3) and connected to the motor driving shaft (3), the motor driving shaft (3) is liquid-tightly penetrated in the front end cover (8) and the rear end cover (9), the front end cover (8), the motor driving shaft (3) and the rear end cover (9) divide the internal space of the motor into an oil chamber and a power chamber, the oil chamber is filled with oil, the speed reducing mechanism (4) is located in the oil chamber, and the stator (1) and the rotor (2) are located in the power chamber.

2. The oil cooling structure of the hub motor according to claim 1 is characterized in that It also includes a motor output shaft (5), a wheel rim (6), a wheel hub (7) and a plurality of bearings, wherein the plurality of bearings are located in the oil chamber, the front end cover (8) and the rear end cover (9) are located on both sides of the wheel hub (7), respectively, the stator (1) is located in the wheel hub (7), the motor driving shaft (3) is transmission-connected to the motor output shaft (5) through the speed reduction mechanism (4), the motor output shaft (5) is fixed to the wheel rim (6), after power is turned on, the stator (1) drives the rotor (2) to rotate, the rotor (2) drives the motor driving shaft (3) to rotate, the motor driving shaft (3) decelerates power through the speed reduction mechanism (4) and outputs it to the motor output shaft (5), and the motor output shaft (5) drives the wheel rim (6) to rotate; The speed reduction mechanism (4) is a planetary gear structure, comprising a sun gear (41), the sun gear (41) being sleeved on the motor output shaft (5) and being rotatable relative to the motor output shaft (5), a connecting shaft (46) being provided in the middle of the sun gear (41), the motor driving shaft (3) being sleeved on the connecting shaft (46) and being positioned and connected to the connecting shaft via a flat key; The motor output shaft (5) is also sleeved with a positioning bearing (51) for axially positioning the sun gear (41); the positioning bearing (51) is a plane thrust bearing; the inner circumference of the positioning bearing (51) is provided with a second positioning step (52); the motor output shaft (5) is provided with a third positioning step; the second positioning step (52) is in contact with the third positioning step.

3. The oil cooling structure of the hub motor according to claim 2 is characterized in that The inner circumferential surface of the front end cover (8) extends toward the rear end cover (9) to form an end cover protrusion (81), the motor driving shaft (3) is liquid-tightly penetrated in the end cover protrusion (81), a driving shaft hole (83) is formed in the end cover protrusion (81), the motor driving shaft (3) is penetrated in the driving shaft hole (83), a first rotary sealing mechanism is provided between the motor driving shaft (3) and the hole wall of the driving shaft hole (83), the first rotary sealing mechanism comprising a first bearing (31) and a first oil seal (33) sleeved on the motor driving shaft (3); An oil seal seat (87) is installed on the side of the front end cover (8), the motor output shaft (5) is inserted into the oil seal seat (87), a second rotary seal mechanism is provided between the motor output shaft (5) and the oil seal seat (87), the second rotary seal mechanism comprises a second oil seal (54) sleeved on the motor output shaft (5) and a second bearing (55); The oil chamber comprises a first oil chamber, the first oil chamber comprises a space between an inner circumferential surface of the front end cover (8) and the motor driving shaft (3), and a space between an inner circumferential surface of the oil seal seat (87) and the motor output shaft (5). The first oil chamber is sealed by the second oil seal (54) and the first oil seal (33). The speed reduction mechanism (4) is located in the first oil chamber, and the second bearing (55), the first bearing (31), and the positioning bearing (51) are also located in the first oil chamber.

4. The oil cooling structure of the hub motor according to claim 3 is characterized in that The oil seal seat (87) is provided with a first insertion ring (88), the first insertion ring (88) is provided with a second installation groove, a sealing ring (89) is provided in the second installation groove, the first insertion ring (88) is inserted into the front end cover (8), and the sealing ring (89) seals the first insertion ring (88) with the inner wall of the front end cover (8); A first oil seal stop groove (86) is formed on the hole wall of the driving shaft hole (83), the first oil seal stop groove (86) is located outside the outer peripheral surface of the first oil seal (33) and adjusts the air pressure, a positioning structure is also provided between the motor driving shaft (3) and the driving shaft hole (83), the positioning structure is in contact with the first oil seal (33) and positions the installation of the first oil seal (33), the positioning structure includes a first retaining ring (32) sleeved on the motor driving shaft (3), and a first oil seal stop groove (86) is formed on the hole wall of the driving shaft hole (83). A retaining ring groove, wherein the first retaining ring (32) is located in the first retaining ring groove, the first retaining ring (32) is in contact with the first oil seal (33), an end of the wall of the driving shaft hole (83) is provided with a first stopper (84) protruding inwardly, two side surfaces of the first bearing (31) are in contact with the first stopper (84) and the first retaining ring (32) respectively, a first mounting groove is further provided on the motor driving shaft (3), a first rubber ring (34) is provided in the first mounting groove, and the first rubber ring (34) is located on the inner side of the first bearing (31); The second rotary sealing mechanism comprises a second oil seal (54) sleeved on the motor output shaft (5), a second bearing (55) and a second rubber ring; a second stopper and a second oil seal stop groove are formed on the inner wall of the oil seal seat (87); the second stopper is located between the second oil seal (54) and the second bearing (55); the second oil seal (54) and the second bearing (55) are both in contact with the second stopper; a third stopper (56) is also formed on the motor output shaft (5); the second bearing (55) is in contact with the third stopper (56); the second oil seal stop groove is located on the outer side of the outer peripheral surface of the second oil seal (54); and the second rubber ring is located on the inner side of the second bearing (55).

5. The oil cooling structure of the hub motor according to claim 3 is characterized in that A bearing seat (91) is installed on the rear end cover (9), a second insertion ring (93) is formed on the bearing seat (91), and the second insertion ring (93) is inserted into the motor driving shaft (3); a disc brake seat (10) is provided outside the bearing seat (91), and a third insertion ring (101) is formed on the disc brake seat (10), and the third insertion ring (101) is inserted into the bearing seat (91); the end of the motor output shaft (5) is inserted into the bearing seat (91) and the disc brake seat (10); a fourth rotary sealing mechanism is provided between the motor output shaft (5) and the inner wall of the bearing seat (91), and the fourth rotary sealing mechanism includes a fourth bearing (57) sleeved on the motor output shaft (5), an O-ring bushing (58) and a sealing O-ring (53), the fourth rotary sealing mechanism also includes a fourth oil seal (59) and a third retaining ring (510) sleeved on the third insert ring (101), the inner wall of the third insert ring (101) is provided with a fifth positioning step, the inner circumference of the third insert ring (101) is in close contact with the O-ring bushing (58), the sealing O-ring (53) is located between the O-ring bushing (58) and the fifth positioning step, the inner wall of the bearing seat (91) is also provided with a fifth retaining block (95) and a third retaining ring groove, the third retaining ring (510) is located in the third retaining ring groove, and the two side surfaces of the fourth oil seal (59) are in contact with the fifth retaining block (95) and the third retaining ring (510) respectively; A first oil gap (516) is formed between the inner wall of the sun gear (41) and the motor output shaft (5), and the oil chamber also includes a second oil chamber, which includes the space between the inner circumference of the motor driving shaft (3) and the motor output shaft (5), and the space between the inner circumference of the bearing seat (91) and the motor output shaft (5). The second oil chamber is connected to the first oil chamber through the first oil gap (516), and the second oil chamber is sealed by the fourth oil seal (59). The fourth bearing (57) is located in the second oil chamber.

6. The oil cooling structure of the hub motor according to claim 5 is characterized in that A third rotary sealing mechanism is provided between the motor driving shaft (3) and the inner wall of the rear end cover (9), the third rotary sealing mechanism comprising a third oil seal (35), a second retaining ring (36), a third bearing (37) and a third rubber ring (39) which are sleeved on the motor driving shaft (3); a second retaining ring groove and a third oil seal stop groove (96) are formed on the inner wall of the rear end cover (9); the second retaining ring (36) is located in the second retaining ring groove; a protruding fourth stop block (92) is also formed on the inner wall of the rear end cover (9); a fourth positioning step (310) is formed on the motor driving shaft (3); two side surfaces of the third bearing (37) are in contact with the fourth stop block (92) and the fourth positioning step (310) respectively; the third oil seal stop groove (96) is located on the outer side of the outer peripheral surface of the third oil seal (35); and the third rubber ring (39) is located on the inner side of the third bearing (37); A second oil gap (94) is formed between the outer wall of the second insert ring (93) and the inner wall of the motor driving shaft (3); the oil chamber includes a third oil chamber; the third oil chamber includes the space between the inner peripheral surface of the rear end cover (9) and the motor driving shaft (3); the third oil chamber is connected to the second oil chamber through the second oil gap (94); the third oil chamber is sealed by the third oil seal (35); and the third bearing (37) is located in the third oil chamber.

7. The oil cooling structure of the hub motor according to claim 6 is characterized in that The front end cover (8) is provided with an oil inlet hole (812) and an oil drain hole (813) which are connected to the first oil chamber. Oil flows into the first oil chamber from the oil inlet hole (812). The oil inlet hole (812) and the oil drain hole (813) are sealed by screws and gaskets. When the motor starts to rotate, the oil flows in the rotating motor and enters the second oil chamber and the third oil chamber to lubricate and cool the speed reduction mechanism (4), the first bearing (31), the second bearing (55), the third bearing (37), the fourth bearing (57), and the positioning bearing (51). The oil drain hole (813) is used to drain the oil.

8. The oil cooling structure of the hub motor according to claim 2 is characterized in that The speed reduction mechanism (4) further comprises a ring gear (44), a planetary support (43) and a plurality of planetary gears (42), wherein the plurality of planetary gears (42) are meshed with the sun gears (41), the planetary gears (42) are meshed with the inner circumference of the ring gear (44), the outer circumference of the ring gear (44) is positioned and connected with the front end cover (8) via a flat key, a planetary gear shaft (45) is provided in the middle of the planetary gear (42), the two ends of the planetary gear shaft (45) are respectively fixed to the planetary support (43) and the motor output shaft (5), the motor driving shaft (3) drives the sun gear (41) to rotate, the sun gear (41) drives the planetary gears (42) to rotate, and the planetary gears (42) transmit power to the motor output shaft (5).

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