CN214707418U

CN214707418U - A deceleration system for in-wheel motor

Info

Publication number: CN214707418U
Application number: CN202121046952.9U
Authority: CN
Inventors: 汪攀峰
Original assignee: Chongqing Guozhou Machinery Manufacturing Co ltd
Current assignee: Chongqing Guozhou Machinery Manufacturing Co ltd
Priority date: 2021-05-14
Filing date: 2021-05-14
Publication date: 2021-11-12
Anticipated expiration: 2031-05-14

Abstract

The utility model provides a speed reduction system for in-wheel motor, including the shaft that is used for installing wheel hub and motor, the epaxial motor drive and pivoted reduction gears that is provided with of wheel, reduction gears is including dismantling the interior casing, the rotation of connecting in the radial side of shaft and connecting in the interior casing outside and be fixed in wheel hub's shell body and connecting in motor output and drive shell body pivoted speed reduction subassembly, the oilhole has been seted up to the shell body, the oilhole can be dismantled and be connected with the jam, the speed reduction subassembly sets up in the shell body. This application has the planetary reduction mechanism who improves through solid-state lubricating oil lubricated wheel hub, and it is dry to easily appear oil, leads to the gear wearing and tearing aggravation, the effect of the not good problem of lubricated effect.

Description

A deceleration system for in-wheel motor

Technical Field

The application relates to the technical field of in-wheel motors, in particular to a speed reduction system for an in-wheel motor.

Background

In-wheel motors, i.e. motors built in the wheels, are characterized by integrating power, transmission and braking devices into the wheel hub, thus greatly simplifying the mechanical parts of the electric vehicle and being widely applied to two-wheeled electric vehicles, such as: electric porters, electric wheelchairs, electric forklifts, and the like. The speed reduction gear set performs transmission speed reduction between the motor and the hub; the parts are more, and the volume is relatively great.

The utility model discloses a chinese utility model patent that publication number is CN209852518U discloses an electric bicycle and in-wheel motor thereof, in-wheel motor includes the output shaft, go out the spool, the wheel hub end cover, the wheel hub casing, motor element and planetary reduction mechanism, go out spool and the coaxial setting of output shaft, the wheel hub end cover passes through wheel hub end cover bearing and column foot and output shaft, wheel hub casing one end is passed through wheel hub bearing and is connected with the outlet shaft, the other end is connected with the wheel hub end cover and forms the installation cavity, motor element and planetary reduction mechanism all set up in the installation cavity, motor element is used for driving planetary reduction mechanism and rotates, planetary reduction adopts two-gang planetary reduction structure, motor element includes rotor core, stator core, magnet steel and winding, stator core and rotor core looks adaptation and locate rotor core's periphery.

The above scheme provides a compact in-wheel motor, but the lubricating oil of the planetary speed reducing mechanism is solid lubricating oil, and the oil is easy to dry, so that the gear wear is aggravated, and the service life is shortened.

SUMMERY OF THE UTILITY MODEL

In order to improve the planet reduction gears through the lubricated wheel hub of solid-state oil, it is dry to easily appear oil, leads to gear wear aggravation, the not good problem of lubricated effect, and this application provides a deceleration system for in-wheel motor.

The application provides a speed reduction system for in-wheel motor adopts following technical scheme:

the utility model provides a deceleration system for in-wheel motor, is including the shaft that is used for installing wheel hub and motor, the epaxial motor drive and pivoted reduction gears that is provided with of wheel, reduction gears is including dismantling to connect in the radial side of shaft interior casing, rotate and connect in the interior casing outside and be fixed in wheel hub's shell body and connect in the motor output and drive shell body pivoted speed reduction subassembly, the oilhole has been seted up to the shell body, the oilhole can be dismantled and be connected with the jam, the speed reduction subassembly sets up in the shell body.

By adopting the technical scheme, the speed reducing assembly is coated by the outer shell to form a sealing structure, so that the whole speed reducing mechanism forms a relatively independent whole relative to the motor, and liquid lubricating oil can be added into the outer shell, so that the speed reducing assembly is lubricated more durably relative to solid lubricating oil, the problems that the gear is abraded and the lubricating effect is poor due to the fact that the speed reducing mechanism of the pulley hub is lubricated by the solid lubricating oil are improved, oil is dried up easily, the gear is abraded and the lubricating effect is poor are solved, and the maintenance operation of oiling and changing the oil of the whole speed reducing system is relatively more convenient; and when the speed reducing device is maintained, the outer shell is taken down, the whole speed reducing system can be uniformly taken out and maintained, the whole hub motor does not need to be maintained, the maintenance is relatively more convenient, the speed reducing system is independent and complete, the whole machine assembly is easy, the assembly qualification rate and the assembly efficiency are improved, and the economic efficiency is higher.

Preferably, the inner shell comprises a shaft sleeve sleeved on the wheel shaft and a mounting piece arranged on the outer side of the shaft sleeve, the inner diameter of one end of the shaft sleeve is larger than the outer diameter of the wheel shaft, the other end of the shaft sleeve is detachably connected to the wheel shaft, and the outer shell is rotatably connected to the radial side of the shaft sleeve.

Through adopting above-mentioned technical scheme, utilize the one end of axle sleeve and the mode of dismantling the connection between the shaft to make and keep relative still between axle sleeve and the shaft, and then make and keep relative still between whole and the axle sleeve of interior casing.

Preferably, one end of the shaft sleeve extends out of the outer shell, and the shaft sleeve is provided with an exhaust hole which is communicated with one side of the shaft sleeve extending out of the outer shell and the inner side of the outer shell.

Through adopting above-mentioned technical scheme for inside the shell, outer atmospheric pressure is balanced relatively, and will be at the long-term operation in-process of speed reduction subassembly, the gas that produces is discharged to the rising of lubricating oil temperature, thereby reaches the effect of ventilating.

Preferably, the exhaust hole and the mounting part are respectively positioned at two radial sides of the wheel axle.

By adopting the technical scheme, the lubricating oil enters the exhaust hole in the running process of the speed reducing assembly, and the probability of oil leakage and seepage is relatively lowest.

Preferably, the exhaust hole is communicated with an exhaust pipe with one end communicated with the inner side of the outer shell, and the other end of the exhaust pipe is bent towards the wheel axle.

By adopting the technical scheme, the lubricating oil is further prevented from entering the exhaust hole to cause oil leakage and seepage.

Preferably, the outer casing includes first casing and the second casing that rotates respectively and connects in outer casing both ends and all be fixed in wheel hub, first casing and second casing one end in opposite directions are each other butt.

Through adopting above-mentioned technical scheme, divide into first casing and second casing with the shell body, the dismouting of being convenient for to with first casing and second casing simultaneously on wheel hub, so that wheel hub and shell body synchronous operation.

Preferably, one end of the first shell, which is rotatably connected to the shaft sleeve, is provided with a sealing ring which abuts against the shaft sleeve; and/or one end of the first shell, which is abutted against the second shell, is provided with a sealing shaft shoulder, which is abutted against the inner side of the second shell.

By adopting the technical scheme, the sealing effect of the sealing ring is utilized to enhance the sealing property between the outer shell and the shaft sleeve and prevent lubricating oil from leaking; utilize sealed shaft shoulder to shelter from the gap between first casing and the second casing to further strengthen the leakproofness between first casing and the second casing, prevent that lubricating oil from spilling.

Preferably, the speed reduction assembly comprises a first-stage driving gear which is rotatably connected in the shaft sleeve and is in clearance fit with the wheel shaft, a first-stage driven gear ring which is arranged in the mounting part and is meshed with the first-stage driving gear, an isolator which is in transmission connection with the inner wall of the first-stage driven gear ring in an outer ring manner, a second-stage driving gear which is in transmission connection with the inner ring of the isolator, and a gear ring which is fixed on the outer shell and is in meshing engagement with the second-stage driving gear in an inner wall manner, wherein one end of the first-stage driving gear extends out of the outer shell and is connected with the output end of the motor.

By adopting the technical scheme, the speed reduction assembly adopts a parallel shaft external meshing and internal meshing speed reduction structure, so that the hub motor has smaller overall volume and compact structure, and simultaneously has larger speed reduction ratio, the motor torque is increased, and better use effect is ensured; and through setting up the isolator for when the vehicle slideed, the motor can not work, and it is far away to slide the distance, to the electric car relatively more power saving.

Preferably, a limiting ring groove is formed in the inner side of the shaft sleeve, and an elastic check ring used for limiting the first-level driving gear is arranged in the limiting ring groove.

Through adopting above-mentioned technical scheme, utilize circlip's limiting displacement, form limiting displacement to the one-level driving gear that the shaft was located to the cover, prevent that the one-level driving gear from taking place axial slip at the pivoted in-process for the shaft.

Preferably, the wheel shaft is provided with a sealing ring groove, and an elastic sealing ring abutted against the shaft sleeve is arranged in the sealing ring groove; and/or one end of the primary driving gear, which extends out of the outer shell, is provided with a sealing ring which is in sealing fit between the primary driving gear and the outer shell.

By adopting the technical scheme, the shaft sleeve is partially abutted against the wheel shaft, so that the vehicle gravity load borne by the wheel shaft can be transferred to the shaft sleeve, then transferred to the outer shell, further transferred to the wheel hub and finally transferred to the wheel; and through setting up elastic sealing ring for the leakproofness between shaft and the axle sleeve further strengthens, simultaneously, the sealing ring that sets up between shell body and the one-level driving gear further forms the oil blanket, thereby forms double seal along shaft axial sealing ring and elastic sealing ring, prevents that oil from oozing outward, the effect of external muddy water internal infiltration is better.

In summary, the present application includes at least one of the following beneficial technical effects:

1. by arranging the speed reduction assembly comprising the first-stage driving gear, the first-stage driven gear ring, the isolator, the second-stage driving gear, the gear ring and other components, the speed reduction ratio is ensured to be large, and meanwhile, the speed reduction assembly is arranged in the outer shell, so that the whole speed reduction system is compact in structure and small in space occupation ratio, and the outer shell forms a coating and sealing effect on the speed reduction assembly, so that liquid lubricating oil can be added into the outer shell to form a more lasting lubricating effect relative to solid lubricating oil on the speed reduction assembly, and the effects of improving the speed reduction mechanism of the pulley hub lubricated by the solid lubricating oil, easily causing the aggravation of gear abrasion and poor lubricating effect are achieved;

2. the exhaust holes and the exhaust pipes which are respectively arranged at the two sides of the radial direction of the wheel shaft and the speed reducing assembly are arranged, so that the lubricating effect of the lubricating oil on the speed reducing assembly is better, the lubricating oil cannot enter the exhaust holes, the oil leakage and the seepage are caused, and meanwhile, the generated gas can be exhausted from the exhaust holes in the long-term use process of the lubricating oil, the ventilation effect inside and outside the shell is ensured, and the balance of the air pressure inside and outside the shell is kept;

3. the outer shell is divided into a first shell and a second shell so as to be convenient to disassemble and assemble; the gear ring is fixed on the outer shell, the outer shell is directly fixed on the hub through the bolt, so that the speed reduction assembly can directly drive the outer shell to rotate and then drive the hub to rotate, namely the outer shell serves as a cladding piece for the speed reduction assembly and has a transmission function of driving the hub to rotate, so that the gear ring is multipurpose, the space occupation ratio of parts and the whole speed reduction system is reduced, and the practicability is higher; meanwhile, the whole speed reducing system forms a whole relative to the motor, so that the speed reducing system is relatively more convenient to disassemble, assemble and maintain, is independent and complete, is easy to assemble, improves the assembly qualification rate and efficiency, and is more economic.

Drawings

FIG. 1 is a schematic diagram of the overall structure of an embodiment of the present application;

FIG. 2 is a first partial cross-sectional structural schematic view of an embodiment of the present application, primarily showing an inner shell and an outer shell;

figure 3 is a second partial cross-sectional structural schematic view of an embodiment of the present application, primarily showing a deceleration assembly.

In the above drawings: 1. a wheel axle; 11. sealing the ring groove; 12. an elastic sealing ring; 2. an inner housing; 21. a shaft sleeve; 211. a limiting ring groove; 212. a circlip; 22. a mounting member; 23. an exhaust hole; 231. an exhaust pipe; 3. an outer housing; 31. a first housing; 311. an oil hole; 312. blocking; 313. sealing the shaft shoulder; 32. a second housing; 33. a bolt; 34. a seal ring; 4. a speed reduction assembly; 41. a primary driving gear; 42. a primary driven gear ring; 43. a one-way clutch; 44. a secondary drive gear; 45. a ring gear.

Detailed Description

The present application is described in further detail below with reference to figures 1-3.

Referring to fig. 1 and 3, the embodiment of the present application provides a speed reduction system for an in-wheel motor, which includes an axle 1, wherein the axle 1 is used for coaxially mounting a wheel hub and a motor component arranged in the wheel hub, and supports a vehicle body through brackets fixed at two ends of the axle 1. The wheel shaft 1 is also provided with a speed reducing system which is fixed at the output end of the motor and is fixed at the wheel hub so as to drive the wheel hub to rotate; the speed reducing system comprises an inner shell 2, an outer shell 3 and a speed reducing assembly 4, wherein the inner shell 2 and the speed reducing assembly 4 are arranged in the outer shell 3, the outer shell 3 is connected to a wheel hub, and the speed reducing assembly 4 is connected to the output ends of the outer shell 3 and a motor to drive the wheel hub to rotate. By arranging the outer shell 3, the speed reduction assembly 4 is integrally coated to form protection and sealing effects, so that liquid lubricating oil can be added, and the problems that oil is dry easily, gear abrasion is aggravated and the lubricating effect is poor due to the fact that the solid lubricating oil is used for lubricating a planetary speed reduction mechanism of the pulley hub are solved; meanwhile, under the action of the outer shell 3, the speed reducing system forms a whole relative to the motor, so that maintenance operations such as disassembly, assembly and replacement are more convenient, the speed reducing system is independent and complete, the whole machine assembly is easy, the assembly qualification rate and the assembly efficiency are improved, and the economic efficiency is higher.

A sealing ring groove 11 is formed in one radial side of one end of the wheel shaft 1, and an elastic sealing ring 12 is arranged in the sealing ring groove 11.

Referring to fig. 2 and 3, the inner case 2 includes a boss 21 and a mounting member 22. The axle sleeve 21 is coaxially sleeved on the axle 1, the inner diameter of at least one end of the axle sleeve 21 is larger than that of the axle 1, so that a space is formed between the axle sleeve 21 and the axle 1, and one end of the axle sleeve 21 is detachably connected to the axle 1, so that the axle sleeve 21 and the axle 1 can keep relatively static; optimally, the inner diameter of one end of the shaft sleeve 21 is larger than the outer diameter of the wheel shaft 1, the inner side of the other end of the shaft sleeve 21 abuts against the wheel shaft 1 to form the sealing effect of the end and the shaft sleeve 21, and the inner side of the end abuts against the elastic sealing ring 12 to relatively enhance the sealing effect and prevent external muddy water from entering; and the sleeve 21 is connected detachably between one end abutting against the wheel axle 1 and the wheel axle 1, so that the sleeve 21 is mounted on the wheel axle 1, the assembly and disassembly are convenient, and the sleeve 21 is prevented from rotating relative to the wheel axle 1. The mounting member 22 is integrally formed on the outer side of the boss 21 and is located at one end of the boss 21 where the inner diameter is larger than the outer diameter of the wheel axle 1, and the inner hole of the mounting member 22 communicates with the inner hole of the boss 21. The detachable connection between the axle sleeve 21 and the axle 1 may be a key connection, a screw connection or an insertion connection of a square rod into a square hole, which is well known to those skilled in the art, and is shown in the figure as an insertion connection of a square rod into a square hole.

The outer case 3 includes a first case 31 and a second case 32, and the first case 31 and the second case 32 abut against each other to be attached and detached. The inner side of one end of the first shell 31 is rotatably connected with the shaft sleeve 21 along the axial direction of the wheel shaft 1, and the other end side of the first shell 31 is abutted with the second shell 32; the inner side of the other end of the second shell 32 is rotatably connected with the shaft sleeve 21; a plurality of bolts 33 are provided on the outer side where the first and

second housings

31 and 32 abut against each other to connect and fix the first and

second housings

31 and 32, and the bolts 33 are threadably attached to the wheel hub to mount the outer housing 3 to the wheel hub. An oil hole 311 is opened in the first housing 31, and a plug 312 is threadedly coupled to the oil hole 311, so that lubricating oil is introduced into the outer housing 3 and waste oil is replaced by opening the plug 312. A sealing shoulder 313 abutted against the inner side of the second shell 32 is integrally formed on the inner side of the first shell 31 abutted against the second shell 32 so as to shield a gap between the first shell 31 and the second shell 32 and prevent oil leakage and internal infiltration of external muddy water; a seal ring 34 is provided at a portion where the first housing 31 is rotatably connected to the sleeve 21, and the seal ring 34 abuts against both the first housing 31 and the sleeve 21 to form an oil seal, thereby further preventing leakage of oil from the rotating portion and infiltration of external muddy water.

The reduction gear unit 4 includes a primary drive gear 41, a primary driven ring gear 42, a non-return device 43, a secondary drive gear 44, and a ring gear 45. The first-stage driving gear 41 is in clearance fit with the wheel shaft 1, and the outer side of the first-stage driving gear 41 is rotatably connected with the shaft sleeve 21; one end of the primary driving gear 41 extends out of the outer shell 3 and is connected with the output end of the motor so as to rotate under the driving of the motor; in addition, one end of the second shell 32 rotatably connected to the shaft sleeve 21 is also provided with a sealing ring 34, and the sealing ring 34 is sealed between the second shell 32 and the primary driving gear 41 to form an oil seal so as to prevent oil leakage from the connection part and internal infiltration of external muddy water; and a sealing ring 34 sleeved on the primary driving gear 41 is also arranged in the shaft sleeve 21, and the sealing ring 34 is close to one end, abutted against the wheel axle 1, of the inner side of the shaft sleeve 21 so as to further form an oil sealing effect on the position. The primary driven gear ring 42 is disposed in the mounting member 22 and engaged with the primary driving gear 41 to be rotated by the rotation of the primary driving gear 41. The one-way clutch 43 is fixed on the inner wall of the one-level driven gear ring 42, and the one-way clutch 43 is arranged, so that when a vehicle slides, a motor can not work, the sliding distance is long, and the electric car is relatively more power-saving. The radial side of the secondary drive gear 44 is fixed to the inner race of the isolator 43 so that the secondary drive gear 44 rotates by the transmission. The outer wall of the gear ring 45 is fixed to the first housing 31, and the gear ring 45 is engaged with the second-stage driving gear 44, so that the gear ring 45 can be driven by the rotating second-stage driving gear 44 to rotate, and further, the outer housing 3 is driven to rotate, and the hub rotates. The connection between the primary driving gear 41 and the output end of the motor may be a key connection, a screw connection or a tooth engagement, which is well known to those skilled in the art, and in the figure, the primary driving gear 41 is shown to be driven to rotate by the tooth engagement.

In order to prevent the first-stage driving gear 41 from axially sliding along the wheel shaft 1, a limiting ring groove 211 is formed in the inner side of the shaft sleeve 21, and an elastic retainer ring 212 is arranged in the limiting ring groove 211, so that a limiting effect is formed on the first-stage driving gear 41 under the action of the elastic retainer ring 212 and a contact end of the shaft sleeve 21 and the wheel shaft 1.

Through setting up shell body 3, with the cladding of speed reduction subassembly 4, form the enclosed construction for liquid lubricating oil can be added in shell body 3, thereby form the lubrication action more lasting for solid lubricating oil to speed reduction subassembly 4, thereby improve the reduction gears through solid-state lubrication oil lubrication wheel hub, oil is dry easily to appear, leads to the gear wearing and tearing aggravation, the not good problem of lubricated effect.

When the sealing ring is installed, the elastic sealing ring 12 is placed in the sealing ring groove 11; then the inner shell 2 is fixed on the wheel axle 1, and the exhaust pipe 231 is installed, in the process, after the inner shell 2 is installed, the exhaust hole 23 is communicated with the opening inside the outer shell 3 upwards, so that the effect of preventing lubricating oil from entering the exhaust hole 23 is optimal; sleeving the first-stage driving gear 41 on the wheel shaft 1, and limiting the first-stage driving gear 41 by using an elastic retainer ring 212; then, the primary driven gear ring 42, the one-way clutch 43, the secondary driving gear 44 and the gear ring 45 are sequentially installed; the first housing 31 and the second housing 32 are successively installed, the first housing 31 and the second housing 32 are connected and fixed by the bolts 33, and in the process, the sealing between the outer housing 3 and the shaft sleeve 21 and the primary driving gear 41 is formed by the sealing ring 34.

Referring to fig. 3, the contact end of the shaft sleeve 21 and the wheel axle 1 is further provided with an exhaust hole 23, the exhaust hole 23 is communicated with the axial side of the shaft sleeve 21 and the inner side of the outer shell 3 to form ventilation, so that the air pressure in the outer shell 3 and the external environment temperature are relatively equal, and the lubricating oil is heated and the generated gas can be relatively timely discharged in the process of high-speed rotation of the speed reducing mechanism.

An exhaust pipe 231 is connected to one end of the exhaust hole 23 connected to the inner side of the outer case 3, and the other end of the exhaust pipe 231 is bent toward the wheel axle 1 to prevent the internal lubricating oil from entering the exhaust hole 23 and leaking oil. Optimally, the exhaust hole 23 and the mounting part 22 are respectively arranged at two radial sides of the wheel axle 1, and after the shaft sleeve 21 is mounted, the exhaust hole 23 is communicated with the opening at the inner side of the outer shell 3 upwards, so that the exhaust hole 23 is communicated with the opening at the inner side of the outer shell 3 upwards all the time in the long-term use process of the speed reducing system, and the effect of preventing lubricating oil from entering the exhaust hole 23 is better.

In the above, the rotation modes between the sleeve 21 and the primary driving gear 41 and the outer housing 3, and between the mounting member 22 and the secondary driving gear 44 are all rotated by the bearings.

Finally, the above embodiments are only used for illustrating the technical solutions of the present application and not for limiting, although the present application is described in detail with reference to the preferred embodiments, it should be understood by those skilled in the art that modifications or equivalent substitutions can be made on the technical solutions of the present application without departing from the spirit and scope of the technical solutions of the present application, and all the technical solutions of the present application should be covered by the claims of the present application.

Claims

1. A reduction system for an in-wheel motor, comprising an axle (1) for mounting a wheel hub and a motor, characterized in that: be provided with on shaft (1) by motor drive and pivoted reduction gears, reduction gears is including dismantling interior casing (2) of connecting in shaft (1) radial side, rotate to connect in interior casing (2) outside and be fixed in wheel hub's shell body (3) and connect in the motor output and drive shell body (3) pivoted speed reduction subassembly (4), oilhole (311) have been seted up in shell body (3), oilhole (311) can be dismantled and be connected with jam (312), speed reduction subassembly (4) set up in shell body (3).

2. The reduction system for an in-wheel motor according to claim 1, wherein: interior casing (2) are located axle sleeve (21) of shaft (1) and are set up in installed part (22) in axle sleeve (21) outside including the cover, the internal diameter of axle sleeve (21) one end is greater than the external diameter of shaft (1), just axle sleeve (21) other end can be dismantled and connect in shaft (1), shell body (3) rotate to be connected in axle sleeve (21) radial side.

3. A speed reduction system for an in-wheel motor according to claim 2, wherein: one end of the shaft sleeve (21) extends out of the outer side of the outer shell (3), and the shaft sleeve (21) is provided with an exhaust hole (23) which is communicated with one side of the shaft sleeve (21) extending out of the outer shell (3) and the inner side of the outer shell (3).

4. A speed reduction system for an in-wheel motor according to claim 3, wherein: the exhaust holes (23) and the mounting pieces (22) are respectively located on two radial sides of the wheel shaft (1).

5. The reduction system for an in-wheel motor according to claim 4, wherein: the exhaust hole (23) is communicated with an exhaust pipe (231) with one end communicated with the inner side of the outer shell (3), and the other end of the exhaust pipe (231) is bent towards the wheel axle (1).

6. The reduction system for an in-wheel motor according to claim 1, wherein: the outer shell (3) comprises a first shell (31) and a second shell (32) which are respectively connected to two ends of the inner shell (2) in a rotating mode and are fixed on the wheel hub, and the opposite ends of the first shell (31) and the second shell (32) are mutually abutted.

7. The reduction system for an in-wheel motor according to claim 6, wherein: one end of the first shell (31) which is rotatably connected with the shaft sleeve (21) is provided with a sealing ring (34) which is abutted against the shaft sleeve (21);

and/or one end of the first shell (31) abutting against the second shell (32) is provided with a sealing shaft shoulder (313),

the sealing shaft shoulder (313) abuts against the inner side of the second shell (32).

8. A speed reduction system for an in-wheel motor according to claim 2, wherein: the speed reduction assembly (4) comprises a first-stage driving gear (41) which is rotatably connected in a shaft sleeve (21) and is in clearance fit with the wheel shaft (1), a first-stage driven gear ring (42) which is arranged on the mounting piece (22) and is meshed with the first-stage driving gear (41), an isolator (43) which is connected to the inner wall of the first-stage driven gear ring (42) in an outer ring transmission mode, a second-stage driving gear (44) which is connected to the inner ring of the isolator (43) in a transmission mode and a gear ring (45) which is meshed with the second-stage driving gear (44) in an inner wall and is fixed on the outer shell (3), and one end of the first-stage driving gear (41) extends out of the outer shell (3) and is connected to the output end of the motor.

9. The reduction system for an in-wheel motor according to claim 8, wherein: the limiting ring groove (211) is formed in the inner side of the shaft sleeve (21), and an elastic check ring (212) used for limiting the first-stage driving gear (41) is arranged in the limiting ring groove (211).

10. The reduction system for an in-wheel motor according to claim 8, wherein: the wheel shaft (1) is provided with a sealing ring groove (11), and an elastic sealing ring (12) abutted against the shaft sleeve (21) is arranged in the sealing ring groove (11);

and/or a sealing ring (34) which is in sealing fit between the primary driving gear (41) and the outer shell (3) is arranged at one end, extending out of the outer shell (3), of the primary driving gear (41).