CN220242987U - Wheel edge driving assembly - Google Patents

Abstract

The utility model provides a wheel driving assembly, which comprises a motor, a half shaft, a first speed reducing mechanism, a second speed reducing mechanism and a wheel hub, wherein the first speed reducing mechanism is connected with the input ends of the motor and the half shaft; the second speed reducing mechanism is connected with the output end of the half shaft; the hub is sleeved outside the second speed reducing mechanism; the speed ratio of the first speed reducing mechanism to the second speed reducing mechanism is 2-7, the overall size and the weight are reduced, and the speed ratio distribution is facilitated.

Description

Wheel edge driving assembly

Technical Field

The utility model belongs to the technical field of vehicles, and particularly relates to a wheel drive assembly.

Background

The wheel side drive belongs to a driving mode of a pure electric automobile and has the advantages of short power transmission line, flexible arrangement, low vehicle bottom plate and the like. At present, the wheel side drive mainly comprises a motor, a speed reducing mechanism, a driving axle and other structures, for example, an independent suspension driving system disclosed by publication No. CN212373145U, and the disclosure is as follows: the motor is arranged beside the tire, the power of the motor is directly transmitted to the hub through the speed reducing mechanism, and the driving axle is arranged between the speed reducing mechanism and the hub, so that the structure of the driving system is more compact, and the transmission efficiency is higher.

The speed reducing mechanism is used for improving the dynamic property of the automobile and realizing the dynamic matching of a transmission system. When designing a two-stage or multi-stage reduction mechanism, the speed ratio allocation of each stage is critical because it directly affects the overall reduction ratio of the complete machine, so that the overall dimensions, bearing capacity, overall weight, selection of lubrication modes, maintenance in operation, etc. of the reduction mechanism will be very directly affected, whereas the gear reduction mechanism of the above patent is a two-stage reduction, has a complex structure, and is large in size.

Disclosure of Invention

In order to solve the above problems, the present utility model provides a wheel drive assembly that reduces overall size and weight and facilitates ratio distribution.

A wheel drive assembly comprising:

a motor;

a half shaft;

the first speed reducing mechanism is connected with the motor and the input end of the half shaft;

the second speed reducing mechanism is connected with the output end of the half shaft;

the hub is sleeved outside the second speed reducing mechanism;

the speed ratio of the first speed reducing mechanism to the second speed reducing mechanism is 2-7.

As a preferred embodiment, the first reduction mechanism and the second reduction mechanism are both planetary gear reduction mechanisms.

As a preferred embodiment, the speed ratio of the first speed reducing mechanism is 2, 2.5, 3, 3.5, 3.65, 4, 4.5, 5, 5.5, 6, 6.5, 7;

and/or the speed ratio of the second speed reducing mechanism is 2, 2.5, 3, 3.5, 3.65, 4, 4.5, 5, 5.5, 6, 6.5, 7.

As a preferred embodiment, the first reduction mechanism includes:

the first speed reduction shell is connected to the motor shell of the motor;

the first planetary gear set is located in the first speed reduction shell, the first planetary gear set comprises a first sun gear, a first planet carrier, a first gear ring and a first planetary gear, the first sun gear is connected with a motor shaft of the motor, the first gear ring is fixed on the inner wall of the first speed reduction shell, the first planet carrier is rotationally arranged in the first speed reduction shell, the first planet carrier is fixedly connected with the input end of the half shaft, the first planetary gear is rotationally arranged on the first planet carrier, and the first planetary gear is respectively meshed with the first sun gear and the first gear ring.

As a preferred embodiment, the first speed reduction housing includes a first main housing and a first end cover, where the first main housing is annular and integrally connected to the motor housing, and the first main housing and the first end cover are detachably connected.

As a preferred embodiment, the second reduction mechanism includes:

the second speed reduction shell is sleeved with the hub;

the second planetary gear set is located inside the second speed reduction shell, the second planetary gear set comprises a second sun gear, a second planet carrier, a second gear ring and a second planet gear, the second sun gear is connected to the output end of the half shaft, the second gear ring is fixed to the inner wall of the second speed reduction shell, the second planet carrier is rotationally arranged inside the second speed reduction shell, the second planet gear is rotationally arranged on the second planet carrier, and the second planet gear is respectively meshed with the second sun gear and the second gear ring.

As a preferred embodiment, the second sun gear comprises a second sun gear tube part and a second sun gear tooth part which are connected, and the second sun gear tube part is spliced on the output end of the half shaft.

As a preferred embodiment, further comprising:

the independent suspension comprises a bridge frame, wherein the bridge frame is provided with a first connecting end and a second connecting end, the first connecting end is fixed on a first speed reduction shell of the first speed reduction mechanism, the second connecting end is inserted into the second speed reduction shell of the second speed reduction mechanism, the second connecting end is connected with a second planet carrier of the second speed reduction mechanism, and the half shaft is positioned in the bridge frame.

As a preferred embodiment, the independent suspension is provided with a lower control arm, an upper control arm, an air bag and a shock absorber.

As a preferred embodiment, the motor is an axial air gap motor.

Compared with the prior art, the technical scheme has the following advantages:

the first speed reducing mechanism and the second speed reducing mechanism are planetary gear speed reducing mechanisms, and the first speed reducing mechanism and the second speed reducing mechanism are reasonably designed, so that speed ratio distribution is facilitated, and the NVH performance of the driving device is improved at the same time after optimized speed ratio distribution.

The motor, the first speed reducing mechanism, the second speed reducing mechanism and the like are kept on the same straight line, compared with the prior motor and the prior hub which are arranged on the same side of the speed reducing mechanism, the radial size is reduced, and the damage caused by the concentrated local stress of the shell of the speed reducing mechanism is prevented.

In addition, the hub is sleeved outside the second speed reducing mechanism, namely the second speed reducing mechanism is at least partially hidden inside the hub, so that the space is reasonably utilized, and the axial size is further reduced.

The utility model is further illustrated by the following examples in conjunction with the accompanying drawings.

Drawings

FIG. 1 is a cross-sectional view of a wheel drive assembly according to the present utility model;

FIG. 2 is an enlarged schematic view of FIG. 1A;

FIG. 3 is a cross-sectional view taken along line B-B of FIG. 1;

FIG. 4 is a cross-sectional view taken along line C-C of FIG. 1;

fig. 5 is a perspective view of a wheel drive assembly according to the present utility model.

In the figure: 100 motor, 110 motor housing, 111 left housing, 112 right housing, 120 motor shaft, 130 cooling channel, 200 half shaft, 300 first reduction mechanism, 310 first reduction housing, 311 first main housing, 311b first main housing step, 312 first end cap, 312a first end cap inner race, 312a1 left inner race portion, 312a2 right inner race portion, 312b first end cap outer race, 312c first end cap side plate, 320 first planetary gear set, 321 first sun gear, 322 first carrier, 322a first left plate, 322b first right plate, 322c first middle plate, 322c1 notch, 322d first left tube, 322e first right tube, 323 first ring gear, 324 first planet gear, 325 first connecting shaft 326 first connecting bearing, 340 first sliding bearing, 400 second reducing mechanism, 410 second reducing housing, 411 second main housing, 412 second end cover, 420 second planetary gear set, 421 second sun gear, 421a second sun gear tube portion, 421b second sun gear tooth portion, 422 second planet carrier, 422a second connecting disc, 422b second sleeve, 422c second connecting shaft, 423 second gear ring, 424 second planet wheel, 430 second sliding bearing, 440 tilt bearing, 450 second connecting bearing, 500 independent suspension, 510 bridge frame, 511 first connecting end, 512 second connecting end, 530 lower control arm, 540 upper control arm, 550 air bag, 560 damper, 600 oil seal.

Detailed Description

The following description is presented to enable one of ordinary skill in the art to make and use the utility model. The preferred embodiments in the following description are by way of example only and other obvious variations will occur to those skilled in the art. The basic principles of the utility model defined in the following description may be applied to other embodiments, variations, modifications, equivalents, and other technical solutions without departing from the spirit and scope of the utility model.

As shown in fig. 1, the wheel drive assembly includes:

a motor 100;

half shafts 200;

a first reduction mechanism 300, wherein the first reduction mechanism 300 is connected with the input ends of the motor 100 and the half shaft 200;

the second speed reducing mechanism 400 is connected with the output end of the half shaft 200;

a hub sleeved outside the second reduction mechanism 400;

the speed ratio of the first reduction mechanism 300 and the second reduction mechanism 400 is 2 to 7.

By reasonably designing the first reduction mechanism 300 and the second reduction mechanism 400, not only is the speed ratio distribution facilitated, but also the NVH performance of the driving device is improved at the same time after the optimized speed ratio distribution. The motor 100, the first reduction mechanism 300, the second reduction mechanism 400, etc. are maintained on the same straight line, so that the increase of the radial dimension is avoided and the damage of the reduction mechanism housing due to the concentrated local stress is prevented compared with the case where the conventional motor and the hub are mounted on the same side of the reduction mechanism. In addition, the hub is sleeved outside the second reduction mechanism 400, that is, the second reduction mechanism 400 is at least partially hidden inside the hub, so that space is reasonably utilized, and the increase of axial dimension is avoided.

As shown in fig. 1 and 2, the motor 100 includes a motor housing 110 and a motor shaft 120 rotatably provided inside the motor housing 110, and the motor shaft 120 penetrates from an output end surface of the motor 100 to be connected to the first reduction mechanism 300.

The distance between the output end face and the non-output end face of the motor 100 defines the thickness of the motor 100, wherein the motor 100 may be an axial field motor, i.e. the thickness of the motor 100 is much smaller than the radial dimension of the motor 100, so that the motor 100 is disc-shaped, and it is seen that with the axial air gap motor, the axial dimension of the wheel drive assembly is further reduced.

The motor 100 further comprises a stator and a rotor, the stator and the rotor are located inside the motor housing 110, the rotor is fixedly connected with the motor shaft 120, the stator is sleeved outside the motor shaft 120, the stator is fixed on the motor housing 110, and an air gap is arranged between the stator and the rotor. The number of the stators and the rotors can be selected according to design requirements, for example, a single-stator single-rotor motor, a single-rotor double-stator motor and the like are adopted.

As shown in fig. 2, the motor housing 110 includes a left case 111 and a right case 112, and the left case 111 and the right case 112 are detachably coupled to facilitate assembly of the motor 100. The left case 111 and the right case 112 may be fixed by bolts or the like.

Bearings are disposed between the motor shaft 120 and the left and right shells 111 and 112, respectively, so that the motor shaft 120 is rotatably disposed in the inner rings of the left and right shells 111 and 112, and the motor shaft 120 penetrates through the right shell 112 and extends to the outside of the motor shell 110, so as to be used for connecting with the first reduction mechanism 300.

As shown in fig. 2, the first reduction mechanism 300 includes:

a first reduction housing 310, the first reduction housing 310 including a first main housing 311 and a first end cap 312, the first main housing 311 being integrally connected to the motor housing 110 of the motor 100, the first end cap 312 and the first main housing 311 being detachably connected;

a first planetary gear set 320, the first planetary gear set 320 is located between the first main housing 311 and the first end cap 312, and the first planetary gear set 320 is connected between the motor shaft 120 and the input end of the half shaft 200.

The first main housing 311 is ring-shaped and integrally connected to the right housing 112 to shorten the overall axial dimension and omit the assembly process. The first main housing 311 and the first end cap 312 may be fixed by bolts or the like, for easy assembly and maintenance of the first reduction mechanism 300.

As shown in fig. 2, the input ends of the motor shaft 120 and the half shaft 200 extend into the first reduction housing 310 to connect the first planetary gear set 320 between the motor shaft 120 and the half shaft 200. Referring to fig. 2 and 3, the first planetary gear set 320 includes:

a first sun gear 321, wherein the first sun gear 321 is connected to the motor shaft 120;

a first planet carrier 322, wherein the first planet carrier 322 is fixedly connected with the input end of the half shaft 200;

a first ring gear 323, the first ring gear 323 being fixed to an inner wall of the first main casing 311;

the first planet gears 324 are rotatably disposed on the first planet carrier 322, and the first planet gears 324 are respectively meshed with the first sun gear 321 and the first ring gear 323.

The first sun gear 321 may be fixed on the motor shaft 120 through a snap spring or a step structure, the left side of the first planet carrier 322 is rotationally connected with the right shell 112, a bearing may be disposed between the two, the right side of the first planet carrier 322 is rotationally connected with the first end cover 312, a bearing may be disposed between the two, and the right side of the first planet carrier 322 is fixedly connected with the input end of the half shaft, so that the motor shaft 120 drives the first sun gear 321 to rotate, and under the cooperation of the first gear ring 323 and the first planet carrier 324, the first planet carrier 322 rotates, and further drives the half shaft 200 to rotate. Wherein the motor shaft 120 and the half shaft 200 are coaxially disposed, thereby avoiding an increase in radial dimension while improving torque transmission efficiency.

Referring to fig. 2, the inner wall of the first main casing 311 is provided with a first main casing step 311b, and the first ring gear 323 is axially restrained between the first main casing step 311b and the first end cap 312.

As shown in fig. 2 and 3, the first carrier 322 includes:

a first left plate 322a, wherein a first left tube 322d is connected to an inner ring of the first left plate 322a, the first left tube 322d is inserted between the motor housing 110 and the motor shaft 120, and the first left tube 322d is rotatably connected to the motor housing 110;

a first right plate 322b, wherein a first right tube 322e is connected to an inner ring of the first right plate 322b, the first right tube 322e is inserted between the first end cover 312 and the half shaft 200, the first right tube 322e is rotatably connected to the first end cover 312, and the first right tube 322e is fixedly connected to the half shaft 200;

the first middle plate 322c, the first middle plate 322c is connected with the outer ring of the first left plate 322a and the outer ring of the first right plate 322b respectively, the first planet 324 is rotatably arranged between the first left plate 322a and the first right plate 322b, the first middle plate 322c is provided with a notch 322c1, and the first planet 324 penetrates out from the notch 322c 1.

The number of the first planetary gears 324 is three, that is, the number of the notches 322c1 is also three, so that the first planetary gears 324 pass through the notches 322c1 and mesh with the first sun gear 321 and the first ring gear 323, respectively.

A first connecting shaft 325 is connected between the first left plate 322a and the first right plate 322b, the first connecting shaft 325 corresponds to the first planetary gears 324 one by one, that is, each first planetary gear 324 is sleeved on the first connecting shaft 325 through a first connecting bearing 326, and because the first gear ring 323 is fixed, the first sun gear 321 drives the first planetary gears 324 to rotate and simultaneously rotate around the axis of the motor shaft 120, so as to drive the first planet carrier 322 to rotate, and further drive the first planet carrier 322 to drive the half shaft 200 to rotate.

As shown in fig. 2, an oil seal 600 is disposed between the right casing 112 and the motor shaft 120, and an oil seal 600 is disposed between the first end cap 312 and the half shaft 200, and two oil seals 600 are disposed on the left and right sides of the first planetary gear set 320, so that the first planetary gear set 320 is lubricated and cooled by oil in the first reduction housing 310, so that the lubrication effect is higher and the reliability is higher.

Since the first planet carrier 322 is held between the right housing 112 and the first end cap 312 and the first main housing 311 surrounds the outer circumference of the first planetary gear set 320, the heat generating element inside the motor 100 and the first planetary gear set 320 are separated only by the right housing 112, which is advantageous in that the motor 100 and the first planetary gear set 320 radiate heat by the same cooling structure, resulting in a simple structure. The heating elements inside the motor 100 include a stator coil, a rotor core, and the like.

The stator of the heating element of the motor 100 is directly fixed on the right shell 112, and the right shell 112 is provided with a cooling channel 130, so that the stator and the first planetary gear set 320 perform heat dissipation together through the cooling channel 130 on the right shell 112. In addition, a cooling channel 130 may be disposed in the left shell 111 to further enhance the cooling effect.

Or, the motor housing 110 is filled with cooling oil, and the heating element is immersed in the cooling oil, so that the first planetary gear set 320 is cooled by the cooling oil filled in the motor housing 110 because the first planetary gear set 320 is disposed close to the right shell 112 of the motor housing 110.

Referring to fig. 2, the first end cap 312 includes a first end cap inner ring 312a, a first end cap outer ring 312b, and a first end cap side plate 312c, the first end cap side plate 312c is connected between the first end cap inner ring 312a and the first end cap outer ring 312b, the first end cap outer ring 312b is abutted and fixed to the first main case 311, and the first ring gear 323 is axially limited between the first main case step 311b and the first end cap outer ring 312 b.

The first planet gears 324 and the first ring gear 323 are kept inside the first main casing 311, and the inner surface of the first end cover side plate 312c is arc-shaped, so that the lubricating oil agitated by the first planet gear set 320 in the first reduction housing 310 can quickly and directly act on the first planet gear set 320 under the limit of the arc-shaped inner surface of the first end cover side plate 312c, and further improve the lubrication effect.

With continued reference to fig. 2, the first end cap inner ring 312a includes a left inner ring portion 312a1 and a right inner ring portion 312a2 that are connected, the inner diameter of the left inner ring portion 312a1 is larger than the inner diameter of the right inner ring portion 312a2, a first sliding bearing 340 is disposed between the left inner ring portion 312a1 and the first right tube 322e, and an oil seal 600 is disposed between the right inner ring portion 312a2 and the half shaft 200.

As shown in fig. 1, the wheel-side driving assembly further includes an independent suspension 500, the independent suspension 500 includes a bridge 510, the bridge 510 has a first connection end 511 and a second connection end 512, the first connection end 511 is fixed on the first reduction housing 310 of the first reduction mechanism 300, the second connection end 512 is inserted into the second reduction housing 410 of the second reduction mechanism 400, the second connection end 512 is connected with the second planet carrier 422 of the second reduction mechanism 400, and the half axle 200 is located in the bridge 510.

It can be seen that the first reduction mechanism 300 is fixed to the first connection end 511, wherein the bridge 510 is wound around the outside of the half shaft 200, and the first connection end 511 is fixed to the first end cap 312 of the first reduction housing 310 by bolts or the like. And the second reduction mechanism 400 is fixed to the second connecting end 512. The bridge 510 may be of an integral or split construction, and is not limited herein.

As shown in fig. 5, the independent suspension 500 is further provided with a lower control arm 530, an upper control arm 540, an air bag 550, a shock absorber 560, and the like.

As shown in fig. 1, the second reduction mechanism 400 includes:

the second speed reduction housing 410, the second speed reduction housing 410 includes a second main housing 411 and a second end cover 412, the second main housing 411 is sleeved outside the second connection end 512, the second end cover 412 is detachably connected to the right side of the second main housing 411, so as to seal the second connection end 512 inside the second speed reduction housing 410, and the hub is sleeved outside the second main housing 411;

the second planetary gear set 420 is connected to the second connection end 512, and the second planetary gear set 420 is located inside the second reduction housing 410.

The second planetary gear set 420 is connected between the second connecting end 512 of the half shaft and the second reduction housing 410, that is, the half shaft 200 drives the second reduction housing 410 and the hub mounted thereon to rotate through the second planetary gear set 420.

As shown in fig. 1 and 4, the second planetary gear set 420 includes:

a second sun gear 421, said second sun gear 421 being connected to the output of said half shaft 200;

a second planet carrier 422, where the second planet carrier 422 is clamped to the second connection end 512;

a second ring gear 423, the second ring gear 423 being fixed to an inner wall of the second main casing 411;

and a second planetary gear 424, wherein the second planetary gear 424 is rotatably arranged on the second planetary gear carrier 422, and the second planetary gear 424 is respectively meshed with the second sun gear 421 and the second gear ring 423.

The second sun gear 421 includes a second sun gear tube 421a and a second sun gear tooth 421b, the second sun gear tube 421a is inserted into the output end of the half shaft 200, and the second sun gear tooth 421b is meshed with the second planet gear 424. A second sliding bearing 430 is disposed between the bridge frame 510 and the second sun gear tube 421a, and between the bridge frame 510 and the second main housing 411, so that the second sun gear 421 and the second reduction housing 410 rotate smoothly with respect to the bridge frame 510, respectively.

The second planet carrier 422 is fixed, wherein the half shaft 200 drives the second sun gear 421 to rotate, the second sun gear 421 drives the second planet gears 424 to rotate, the second planet gears 424 drive the second gear ring 423, and the second main housing 411 to which the second gear ring 423 is connected rotates.

The second carrier 422 includes:

a second land 422a, the second land 422a abutting on an end face of the second connection terminal 512;

a second bushing 422b, the second bushing 422b being connected to the left side of the connection pad 422a, the second bushing 422b being interposed between the bridge 510 and the second main housing 411, the second main housing 411 and the second bushing 422b being rotatably connected;

and a second connection shaft 422c, wherein the second connection shaft 422c is connected to the right side of the second connection disc 422a, and the second planetary gears 424 are rotatably arranged on the second connection shaft 422 c.

An inclined bearing 440 is provided between the second main housing 411 and the second sleeve 422 b. Referring to fig. 1 and 4, the number of the second connection shafts 422c and the second planetary gears 424 is three, and a second connection bearing 450 is provided between each of the second planetary gears 424 and the second connection shafts 422 c.

Referring to fig. 1, the hub is sleeved outside the second main housing 411, wherein the second reduction mechanism 400 is at least partially embedded inside the hub, avoiding an increase in axial dimension.

As shown in fig. 1, the input end of the half shaft 200 is inserted into the first planet carrier 322 of the first reduction mechanism 300, and the output end of the half shaft 200 is inserted into the second sun gear 421 of the second reduction mechanism 400, so that the half shaft 200 has a simple structure, and the diameter of the half shaft 200 can be small, so that the size of the half shaft is further reduced.

As shown in fig. 1, an oil seal 600 is disposed between the second main housing 411 and the axle shaft 200, and the bridge frame 510 of the independent suspension 500, and the two oil seals 600 are located on a side of the second planetary gear set 420 away from the second end cover 412, so that the second reduction mechanism 400 is lubricated by oil in the second reduction housing 410, and the structure is simple and the lubrication effect is good.

The first reduction mechanism 300 and the second reduction mechanism 400 are planetary gear reduction mechanisms, and have the advantages of compact structure, stable transmission, large torque and the like. The speed ratio of the first speed reducing mechanism 300 is between 2 and 7, and the first speed reducing mechanism 300 is exemplified by the speed ratio of the first sun gear 321 to the first planet gear 324, and the speed ratio of the first speed reducing mechanism 300 is 2, 2.5, 3, 3.5, 3.65, 4, 4.5, 5, 5.5, 6, 6.5 and 7. Taking the second reduction mechanism 400 as an example, the second reduction mechanism 400 is a speed ratio of the second sun gear 421 to the second planetary gear 424, and the speed ratio of the second reduction mechanism 400 is 2, 2.5, 3, 3.5, 3.65, 4, 4.5, 5, 5.5, 6, 6.5, 7.

The speed ratio of the planetary gear reduction mechanism can be expressed by the following formula: speed ratio= (sun gear number + planet gear number)/sun gear number x planet gear number.

It can be seen that as the number of planets increases, the speed ratio also increases, thus achieving a greater reduction ratio. Meanwhile, the contact points between gear teeth are increased by increasing the number of the planetary gears, so that the transmission efficiency and the running stability are improved.

In summary, the motor 100, the first reduction mechanism 300, the second reduction mechanism 400, etc. are kept on the same straight line, so that the radial dimension is reduced and the reduction mechanism housing is prevented from being damaged due to concentrated local stress, compared to the conventional motor and hub mounted on the same side of the reduction mechanism. In addition, the hub is sleeved outside the second reduction mechanism 400, that is, the second reduction mechanism 400 is at least partially hidden inside the hub, so that the space is reasonably utilized, and the axial dimension is further reduced. The first speed reducing mechanism 300 and the second speed reducing mechanism 400 are planetary gear speed reducing mechanisms, and by reasonably designing the first speed reducing mechanism 300 and the second speed reducing mechanism 400, not only is the speed ratio distribution facilitated, but also the NVH performance of the driving device is improved at the same time after the optimized speed ratio distribution. The motor shaft 120 and the half shaft 200 are coaxially disposed, reducing the radial size and improving the torque transmission efficiency. The first reduction mechanism 300 and the second reduction mechanism 400 can be lubricated by oil, and reliability is high. The motor 100 and the first reduction mechanism 300 share a cooling structure, so that the structure is simpler, which is beneficial to reducing the volume of the driving assembly.

The above-described embodiments are only for illustrating the technical spirit and features of the present utility model, and it is intended to enable those skilled in the art to understand the content of the present utility model and to implement it accordingly, and the scope of the present utility model as defined by the present embodiments should not be limited only by the present embodiments, i.e. equivalent changes or modifications made in accordance with the spirit of the present utility model will still fall within the scope of the present utility model.

Claims (10)

1. A wheel drive assembly, comprising:

an electric motor (100);

a half shaft (200);

the first speed reducing mechanism (300) is connected with the input ends of the motor (100) and the half shaft (200);

the second speed reducing mechanism (400) is connected with the output end of the half shaft (200);

a hub sleeved outside the second speed reducing mechanism (400);

the speed ratio of the first speed reducing mechanism (300) and the second speed reducing mechanism (400) is 2-7.

2. The wheel drive assembly of claim 1, wherein the first reduction mechanism (300) and the second reduction mechanism (400) are both planetary gear reduction mechanisms.

3. The wheel drive assembly of claim 1, wherein the first reduction mechanism (300) has a speed ratio of 2, 2.5, 3, 3.5, 3.65, 4, 4.5, 5, 5.5, 6, 6.5, 7;

and/or the speed ratio of the second speed reducing mechanism (400) is 2, 2.5, 3, 3.5, 3.65, 4, 4.5, 5, 5.5, 6, 6.5, 7.

4. The wheel drive assembly of claim 1, wherein the first reduction mechanism (300) comprises:

a first reduction housing (310), the first reduction housing (310) being connected to a motor housing (110) of the motor (100);

first planet group (320), first planet wheelset (320) are located in first reduction casing (310), first planet wheelset (320) include first sun gear (321), first planet carrier (322), first ring gear (323) and first planet (324), first sun gear (321) are connected motor shaft (120) of motor (100), first ring gear (323) are fixed in on the inner wall of first reduction casing (310), first planet carrier (322) rotate set up in first reduction casing (310), and first planet carrier (322) with the input fixed connection of semi-axis (200), first planet carrier (324) rotate set up in on first planet carrier (322), first planet carrier (324) respectively with first sun gear (321) with first ring gear (323) meshing.

5. The wheel drive assembly of claim 4, wherein the first reduction housing (310) includes a first main housing (311) and a first end cap (312), the first main housing (311) being annular and integrally connected to the motor housing (110), the first main housing (311) and the first end cap (312) being detachably connected.

6. The wheel drive assembly of claim 1, wherein the second reduction mechanism (400) comprises:

the second speed reduction shell (410), the second speed reduction shell (410) is sleeved with the hub;

the second planetary gear set (420), second planetary gear set (420) are located inside second speed reduction casing (410), second planetary gear set (420) include second sun gear (421), second planet carrier (422), second ring gear (423) and second planet wheel (424), second sun gear (421) connect in on the output of semi-axis (200), second ring gear (423) are fixed in on second speed reduction casing (410) inner wall, second planet carrier (422) rotate set up in inside second speed reduction casing (410), second planet wheel (424) rotate set up in on second planet carrier (422), second planet wheel (424) respectively with second sun gear (421) with second ring gear (423) mesh.

7. The wheel side drive assembly of claim 6, wherein the second sun gear (421) includes a second sun gear tube portion (421 a) and a second sun gear tooth portion (421 b) connected, the second sun gear tube portion (421 a) being plugged onto the output end of the half shaft (200).

8. The wheel drive assembly as defined in claim 1, further comprising:

independent suspension (500), independent suspension (500) includes crane span structure (510), crane span structure (510) have first link (511) and second link (512), first link (511) are fixed in on first reduction gear (300) first reduction gear's (310), second link (512) insert inside second reduction gear's (400) second reduction gear's (410), second link (512) are connected second planet carrier (422) of second reduction gear (400), semi-axis (200) are located inside crane span structure (510).

9. The wheel drive assembly of claim 8, wherein the independent suspension (500) is provided with a lower control arm (530), an upper control arm (540), an air bag (550), and a shock absorber (560).

10. Wheel drive assembly according to any of claims 1 to 9, wherein the electric machine (100) is an axial air gap electric machine.