CN221113494U - Power assembly and electric vehicle - Google Patents

Abstract

The embodiment of the application provides a power assembly and an electric vehicle, wherein the power assembly comprises a shell, a motor, a speed reducer, a first bearing and a limiting ring, the shell is used for fixing a stator of the motor and an outer ring of the first bearing, a motor shaft of the motor comprises a cylindrical inner coupling end, an input shaft of the speed reducer comprises a groove-shaped outer coupling end, and the inner coupling end comprises: the outer peripheral surface of the outer coupling end is used for fixedly connecting with the inner ring of the first bearing, and the inner peripheral surface of the outer coupling end is used for being in transmission connection with the outer peripheral surface of the inner coupling end; the inner peripheral surface of the outer coupling end comprises a first groove, the outer peripheral surface of the inner coupling end comprises a second groove, and the first groove and the second groove are used for accommodating the limiting ring.

Description

Power assembly and electric vehicle

Technical Field

The application relates to the technical field of driving, in particular to a power assembly and an electric vehicle.

Background

The powertrain is the source of power for the electric vehicle. The power assembly comprises a motor and a speed reducer. The rotor shaft of the motor is coaxially driven with the input shaft of the speed reducer. When the power assembly works, the rotor shaft can displace along the axial direction of the rotor shaft due to vibration, magnetic pulling force and the like, which can damage the power assembly and affect the reliability of the power assembly.

Disclosure of utility model

The embodiment of the application provides a power assembly capable of improving reliability and an electric vehicle.

In a first aspect, the present application provides a powertrain, the powertrain comprising a housing, a motor, a reducer, a first bearing, and a stop collar, the housing being configured to secure a stator of the motor and an outer race of the first bearing, a motor shaft of the motor comprising a cylindrical inner coupling end, an input shaft of the reducer comprising a grooved outer coupling end, wherein: the outer peripheral surface of the outer coupling end is used for fixedly connecting with the inner ring of the first bearing, and the inner peripheral surface of the outer coupling end is used for being in transmission connection with the outer peripheral surface of the inner coupling end; the inner peripheral surface of the outer coupling end comprises a first groove, the outer peripheral surface of the inner coupling end comprises a second groove, and the first groove and the second groove are used for accommodating the limiting ring.

In the working process of the power assembly, the rotor easily slides along the axial direction of the rotor due to vibration, magnetic pulling force and the like, the axial sliding of the rotor shaft can cause problems of noise, vibration and noise vibration harshness (Noise, vibration, harshness, NVH), and damage is caused to devices in the power assembly, such as a bearing and the like, so that the reliability of the power assembly is affected.

According to the limiting ring of the power assembly, when the motor shaft moves along the axial direction of the motor, the limiting ring is propped against the side wall of the second groove to limit the axial sliding between the motor shaft and the input shaft, so that the occurrence of NVH is reduced, and the reliability of the power assembly is improved.

In a possible implementation manner of the present application, according to the first aspect, the notch of the first groove faces towards the axis of the input shaft, and the notch of the second groove faces away from the axis of the motor shaft.

In this possible implementation, the notch of the first groove faces the axis of the input shaft, and the notch of the second groove faces away from the axis of the motor shaft, so that the limit ring can conveniently enter the first groove and the second groove.

In a possible implementation manner of the present application, according to the first aspect, the depth of the second groove is greater than the depth of the first groove along the radial direction of the motor.

In this possible implementation, the stop collar is conveniently inserted into the first recess and the second recess.

In a possible implementation manner of the present application, according to the first aspect, a depth of at least one of the first groove or the second groove is greater than one half of a thickness of the stop collar along a radial direction of the motor.

In this possible implementation, the stop collar may be placed in the second recess before the inner coupling end is inserted into the outer coupling end during assembly. Because the depth of the second groove is greater than one half of the thickness of the limiting ring, the limiting ring with the thickness exceeding one half is accommodated in the second groove, and the limiting ring is not easy to separate from the second groove in the process of inserting the inner coupling end into the outer coupling end, so that the smoothness of the process of inserting the inner coupling end into the outer coupling end is improved.

According to a first aspect, in a possible implementation manner of the present application, along an axial direction of the motor, an inner circumferential surface of the outer coupling end includes an inner cylindrical section and a spline section, a radius of the inner cylindrical section is larger than a radius of the spline section, the spline section is used for spline connection with the inner coupling end, a distance between an end surface of the spline section and an end surface of the outer coupling end facing the motor is larger than a distance between an end surface of the inner cylindrical section facing the motor, and a radial projection of the first groove along the input shaft is located on the spline section.

In the possible implementation manner, the spline connection realizes mechanical transmission between the inner coupling end and the outer coupling end, and simultaneously can limit the relative rotation of the inner coupling end and the outer coupling end in the circumferential direction of the motor, so that the transmission stability between the inner coupling end and the outer coupling end is improved. The distance between the spline section and the end face of one side of the outer coupling end, which faces the motor, is larger than the distance between the inner cylindrical surface section and the end face of one side of the motor, the radial projection of the first groove along the input shaft is positioned on the spline section, the rotor, the first bearing and the limiting ring are sequentially arranged along the axial direction of the motor, and the limiting ring limits the relative sliding between the inner coupling end and the outer coupling end on the motor shaft.

In a possible implementation manner of the present application according to the first aspect, the length of the spline section is greater than the length of the inner cylindrical section in the axial direction of the motor, and the length of the inner cylindrical section is greater than the length of the first bearing.

In the possible implementation manner, the length of the spline section is larger than that of the outer cylindrical surface section, so that the spline connection length of the inner coupling end and the outer coupling end can be increased, and the transmission stability of the inner coupling end and the outer coupling end is further improved.

According to a first aspect, in one possible implementation manner of the present application, along an axial direction of the motor, an outer circumferential surface of the inner coupling end includes an outer cylindrical surface section and a spline section, a radius of the outer cylindrical surface section is larger than a radius of the spline section, the spline section is used for spline connection with an inner circumferential surface of the outer coupling end, a distance between the spline section and an end surface of the inner coupling end facing a side of the speed reducer is smaller than a distance between end surfaces of the outer cylindrical surface section facing the speed reducer, and a radial projection of the second groove along the motor shaft is located on the spline section.

In this possible implementation manner, the outer cylindrical section is used for supporting the input shaft in an auxiliary manner, the radius of the outer cylindrical section is larger than that of the spline section, and the spline section is used for being in spline connection with the inner peripheral surface of the outer coupling end so as to realize mechanical transmission between the inner coupling end and the outer coupling end. The spline connection realizes mechanical transmission between the inner coupling end and the outer coupling end, and simultaneously can limit the relative rotation of the inner coupling end and the outer coupling end in the circumferential direction of the motor, so that the transmission stability between the inner coupling end and the outer coupling end is improved.

In a possible implementation manner of the present application according to the first aspect, the length of the spline section is greater than the length of the outer cylindrical section in the axial direction of the motor, and the length of the outer cylindrical section is greater than the length of the first bearing.

In the possible implementation manner, the length of the spline section is larger than that of the outer cylindrical surface section, so that the spline connection length of the inner coupling end and the outer coupling end can be increased, and the transmission stability of the inner coupling end and the outer coupling end is further improved.

According to a first aspect, in a possible implementation manner of the present application, a distance between a side wall of the first groove facing the stator side and an end surface of the out-coupling end facing the stator side is not smaller than a distance between a side wall of the second groove facing the stator side and an end surface of the out-coupling end facing the stator side in an axial direction of the motor.

In this possible implementation manner, when no axial sliding occurs in the motor shaft, a distance between a side wall of the first groove facing the stator and an end face of the coupling-out end facing the stator is equal to a distance between a side wall of the second groove facing the stator and an end face of the coupling-out end facing the stator. When the motor shaft axially slides along the direction of the speed reducer towards the motor, the distance between the side wall of the first groove towards one side of the stator and the end face of the outer coupling end towards one side of the stator is larger than the distance between the side wall of the second groove towards one side of the stator and the end face of the outer coupling end towards one side of the stator.

Because the outer ring of the first bearing is fixed on the shell, when the motor shaft axially slides along the speed reducer towards the motor, the first groove and the second groove are possibly dislocated, the side wall of the first groove towards one side of the motor abuts against the limiting ring, and further the movement of the motor shaft from the speed reducer towards the motor is limited.

In a possible implementation manner of the present application, according to the first aspect, the power assembly further comprises a second bearing, the input shaft comprises a bearing connection end and a gear connection section, and two ends of the gear connection section are respectively used for connecting the bearing connection end and the outcoupling end of the input shaft, wherein: the shell is used for fixing the outer ring of the second bearing, the inner ring of the second bearing is used for being fixedly connected with the bearing connecting end of the input shaft, and the gear connecting section is used for being in transmission connection with at least one gear of the speed reducer.

In a possible implementation manner of the present application, according to the first aspect, the diameter of the gear connection section is larger than the diameter of the bearing connection end of the input shaft and larger than the inner diameter of the inner ring of the second bearing, and the diameter of the gear connection section is larger than the diameter of the outer coupling end and smaller than the inner diameter of the inner ring of the first bearing; and the length of the gear connecting section is smaller than or equal to the interval between the first bearing and the second bearing along the axial direction of the motor.

In a possible implementation manner of the present application, according to the first aspect, the housing includes an intermediate housing for fixing the outer ring of the first bearing and a reducer end cap for fixing the outer ring of the second bearing.

According to a first aspect, in a possible implementation manner of the present application, the power assembly comprises a third bearing, the motor shaft comprises a bearing connection end and a rotor connection section, two ends of the rotor connection section are respectively used for connecting the bearing connection end and the in-coupling end of the motor shaft, and the rotor connection section is used for fixedly connecting the rotor of the motor, wherein: the shell is used for fixing the outer ring of the third bearing, and the inner ring of the third bearing is used for fixedly connecting the bearing connecting end of the motor shaft.

In the implementation mode, the inner ring of the third bearing is connected with the motor shaft, the outer ring of the third bearing is connected with the shell, and if the motor shaft axially slides along the speed reducer towards the motor direction, the third bearing is easy to impact, so that the third bearing is easy to damage. The axial movement of the motor shaft along the direction of the speed reducer towards the motor is limited by the limiting ring, so that the impact of a third bearing positioned on the motor shaft is reduced. The impact on the third bearing is reduced, so that the axial machining precision of the part of the shell containing the third bearing can be correspondingly reduced, the machining cost of the shell is reduced, and the reliability of the shell and the third bearing is improved.

According to a first aspect, in one possible implementation manner of the present application, a diameter of one end of the rotor connection section is larger than a diameter of a bearing connection end of the motor shaft and larger than an inner diameter of an inner ring of the third bearing, a diameter of the other end of the rotor connection section is larger than a diameter of the inner coupling end and larger than an inner diameter of the inner ring of the first bearing, and a length of the rotor connection section is smaller than or equal to a spacing between the first bearing and the third bearing in the motor axial direction.

In this possible embodiment, the diameter of the other end of the rotor connection section is greater than the diameter of the inner coupling end and greater than the inner diameter of the inner ring of the first bearing, so that the rotor connection section forms a limiting end face. The limiting end face is used for propping against the end face, facing the motor, of the outer coupling end so as to limit the axial movement of the motor shaft along the direction of the motor facing the speed reducer, reduce the occurrence of NVH and improve the reliability of the power assembly. The diameter of one end of the rotor connecting section is larger than the diameter of the bearing connecting end of the motor shaft and larger than the inner diameter of the inner ring of the third bearing, so that a first limiting shaft shoulder for axially limiting the third bearing is formed towards the bearing connecting end of the motor shaft, and the possibility of axial movement of the third bearing relative to the motor shaft is reduced.

According to a first aspect, in one possible implementation of the application, the housing comprises an intermediate housing for fixing the outer ring of the first bearing and a motor end cover comprising a bearing receiving groove for receiving a wave pad and the third bearing, the wave pad being arranged between a groove bottom of the bearing receiving groove and the third bearing.

In a second aspect, an embodiment of the present application further provides an electric vehicle, where the electric vehicle includes a vehicle body, wheels, and the powertrain according to the first aspect, the vehicle body is configured to fix the powertrain, and the powertrain is connected to the wheels and is configured to drive the wheels.

Drawings

FIG. 1 is a schematic view of a vehicle according to an embodiment of the present application;

FIG. 2 is a schematic diagram of a powertrain according to an embodiment of the present application;

FIG. 3 is a schematic view of a portion of a powertrain according to an embodiment of the present application;

FIG. 4 is a schematic diagram of a powertrain according to an embodiment of the present application;

FIG. 5 is a cross-sectional view of the powertrain shown in FIG. 4 along AA;

FIG. 6 is a cross-sectional view of a powertrain with a housing removed in accordance with an embodiment of the present application;

FIG. 7 is an enlarged schematic view of a partial region I of the powertrain shown in FIG. 6;

FIG. 8 is an enlarged schematic view of a portion of the area of FIG. 7;

Fig. 9 is a cross-sectional view of a portion of the structure of a powertrain when axial play of a motor shaft in the direction of the motor occurs along a decelerator, in accordance with an embodiment of the present application.

Detailed Description

The following description of the technical solutions according to the embodiments of the present application will be given with reference to the accompanying drawings in the embodiments of the present application, and it is apparent that the described embodiments are only some embodiments of the present application, but not all embodiments.

The terms "first," "second," and the like herein are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include one or more such feature. In the description of the present application, unless otherwise indicated, the meaning of "a plurality" is two or more.

Furthermore, herein, the terms "upper," "lower," and the like, are defined with respect to the orientation in which the structure is schematically disposed in the drawings, and it should be understood that these directional terms are relative concepts, which are used for descriptive and clarity with respect thereto and which may be varied accordingly with respect to the orientation in which the structure is disposed.

For convenience of understanding, the following description will explain and describe related technical terms related to the embodiments of the present application.

Parallel: the parallelism defined by the embodiments of the present application is not limited to absolute parallelism, and the definition of parallelism is understood to be substantially parallel, allowing for non-absolute parallelism due to factors such as assembly tolerances, design tolerances, structural flatness, etc.

And (3) vertical: the vertical defined in the embodiments of the present application is not limited to an absolute vertical intersection (the included angle is 90 degrees), and allows a small angle range of error, for example, an assembly error range ranging from 80 degrees to 100 degrees, to be understood as a vertical relationship in a relation other than an absolute vertical intersection due to factors such as assembly tolerance, design tolerance, and structural flatness.

First direction Y: parallel to the motor axial direction, the motor axial direction refers to the axial direction of the motor shaft.

Second direction Z: perpendicular to the first direction Y and the third direction X.

Third direction X: perpendicular to the first direction Y and the second direction Z.

The powertrain is the source of power for the electric vehicle. The power assembly comprises a motor and a speed reducer. The rotor shaft of the motor is coaxially driven with the input shaft of the speed reducer. When the power assembly works, the rotor shaft can displace along the axial direction of the rotor shaft due to vibration, magnetic pulling force and the like, which can damage the power assembly and affect the reliability of the power assembly.

Based on this, the embodiment of the application provides a power assembly, which comprises a shell, a motor, a speed reducer, a first bearing and a limiting ring, wherein the shell is used for fixing a stator of the motor and an outer ring of the first bearing, a motor shaft of the motor comprises a cylindrical inner coupling end, and an input shaft of the speed reducer comprises a groove-shaped outer coupling end, wherein: the outer peripheral surface of the outer coupling end is used for fixedly connecting with the inner ring of the first bearing, and the inner peripheral surface of the outer coupling end is used for being in transmission connection with the outer peripheral surface of the inner coupling end; the inner peripheral surface of the outer coupling end comprises a first groove, the outer peripheral surface of the inner coupling end comprises a second groove, and the first groove and the second groove are used for accommodating the limiting ring.

The power assembly provided by the embodiment of the application is applied to the electric vehicle, and the overall performance of the electric vehicle is improved.

Referring to fig. 1, fig. 1 is a schematic structural diagram of an electric vehicle 1 according to an embodiment of the application. In the embodiment of the application, the electric vehicle 1 includes a powertrain 10, a vehicle body 20, a battery pack 30, and wheels 40. The power assembly 10 and the battery pack 30 are fixed to the vehicle body 20. The powertrain 10 is configured to receive power from the battery pack 30 and to drive the wheels 40.

In embodiments of the present application, the battery pack 30 may also be referred to as a power battery.

In the embodiment of the present application, the electric vehicle 1 refers to a wheeled apparatus driven or towed by a power device. Exemplary electric vehicles 1 include electric vehicles (ELECTRIC VEHICLE, EV for short), battery ELECTRIC VEHICLE, BEV for short, hybrid ELECTRIC VEHICLE, HEV for short, range Extended ELECTRIC VEHICLE, REEV for short, plug-in Hybrid ELECTRIC VEHICLE, PHEV for short, and the like.

In an embodiment of the present application, the electric vehicle 1 includes one or more subassemblies 10. In one embodiment, the electric vehicle 1 is a front-drive or rear-drive vehicle. Wherein the electric vehicle 1 comprises a powertrain 10, the powertrain 10 being adapted to drivingly connect the front or rear wheels of the electric vehicle 1. In one embodiment, the electric vehicle 1 is a front-rear dual drive vehicle. Wherein the electric vehicle 1 comprises two subassemblies 10. The two subassemblies 10 are respectively for driving the front wheels and the rear wheels of the electric vehicle 1. In one embodiment, the electric vehicle 1 is a front-rear four-drive vehicle. Wherein the electric vehicle 1 comprises four subassemblies 10. The four subassemblies 10 are each for driving four wheels of the electric vehicle 1.

The powertrain 10 provided by the embodiment of the present application will be described in detail.

Referring to fig. 2 and 3, fig. 2 is a schematic structural diagram of a power assembly 10 according to an embodiment of the application, and fig. 3 is a schematic partial structural diagram of the power assembly 10 according to an embodiment of the application.

The powertrain 10 includes a motor 100, a motor controller 200, a decelerator 300, and a housing 400. Wherein the motor controller 200 is for receiving the direct current of the battery pack 30 and for outputting the alternating current to the motor 100. The motor 100 is for receiving alternating current output from the motor controller 200 and for driving wheels 40 of the electric vehicle 1. The decelerator 300 serves to transmit power of the motor 100 to the wheels 40. The housing 400 accommodates the motor 100, the motor controller 200, and the decelerator 300.

Referring to fig. 4 and fig. 5 in combination, fig. 4 is a schematic structural diagram of a power assembly according to an embodiment of the application; fig. 5 is a cross-sectional view of the powertrain shown in fig. 4 along AA.

The motor 100 includes a stator 110, motor windings 120, a rotor 130, and a motor shaft 140. The interaction between the alternating magnetic flux generated by the motor winding 120 and the permanent magnetic flux generated by the rotor causes the rotor 130 to rotate relative to the stator 110, the rotor 130 is fixedly connected with the motor shaft 140, the motor shaft 140 follows the rotor 130 to rotate, the stator 110 is rotationally connected with the motor shaft 140, the motor shaft 140 can rotate relative to the stator 110, electric energy is converted into mechanical energy, and the output end of the motor shaft 140 is used for transmitting the mechanical energy. The decelerator 300 includes an input shaft 310. The input shaft 310 is in driving connection with the motor shaft 140 to rotate under the driving of the motor shaft 140.

The powertrain 10 further includes a first bearing 150, a second bearing 160, a third bearing 170, a wave washer 180, and a stop collar 190.

The housing 400 is used to fix the stator 110 of the motor 100, the outer race 152 of the first bearing 150, the outer race 162 of the second bearing 160, and the outer race 172 of the third bearing 170. In some embodiments of the application, the housing 400 includes a middle housing 411, a reducer end cap 413, and a motor end cap 415. The motor end cover 415 is fixed to one end of the intermediate housing 411 in the motor axial direction Y, and the reducer end cover 413 is fixed to the other end of the intermediate housing 411 in the motor axial direction Y. The motor end cover 415, the intermediate housing 411, and the speed reducer end cover 413 are arranged in this order in the motor axial direction Y. The motor 100, the motor controller 200 (not shown in fig. 5), and the decelerator 300 are housed in the intermediate housing 411. The intermediate housing 411 is used to fix the outer race 152 of the first bearing 150. The motor end cap 415 includes a bearing receiving groove 4152, the bearing receiving groove 4152 for receiving the wave pad 180 and the third bearing 170. The reducer cap 413 is used to secure the outer race 162 of the second bearing 160.

In some embodiments of the present application, motor 100, motor controller 200, and reducer 300 share an integrated housing 400. In one embodiment, the housing 400 may be a split structure, for example, the housing 400 may include a motor housing, a controller housing, and a reducer housing that are configured separately, and the motor housing encloses a motor housing cavity. The controller housing encloses and establishes and form the controller and hold the chamber, and the reduction gear housing encloses and establishes and form the reduction gear and hold the chamber. In one embodiment, the motor housing and the controller housing are an integrally formed structure, or the speed reducer housing and the controller housing are an integrally formed structure. In one embodiment, the motor housing and the control housing share an adjacent portion of the housing. In one embodiment, the motor housing, the controller housing and the speed reducer housing are of an integrally formed construction.

The input shaft 310 is used to fix the inner race 154 of the first bearing 150 and the inner race 164 of the second bearing 160. The motor shaft 140 is used to secure the inner race 174 of the third bearing 170. Along the motor axial direction Y, the third bearing 170, the rotor 130, the first bearing 150, and the second bearing 160 are arranged in this order. The wave pad 180 is accommodated in the case 400. The wave pad 180 abuts against the third bearing 170 to axially pre-tension the motor shaft 140. The wave pad 180 is arranged between the groove bottom of the bearing housing groove 4152 and the third bearing 170. The wave pad 180 may be a wave spring or belleville spring or other resilient member, etc.

Compared with a power assembly with four bearings, the power assembly 10 with three bearings has the advantages that the number of bearings is reduced and the manufacturing cost is reduced while the better comprehensive performance is maintained. Compared with a power assembly with a two-bearing supporting mode, the power assembly 10 supported by adopting the three-bearing mode has better comprehensive performance, and in addition, the distance between two adjacent bearings is shortened, so that the preparation difficulty and the assembly difficulty of the power assembly 10 are reduced. It will be appreciated that the application is not limited to the number of bearings used, for example, the number of bearings may be two or four.

Referring to fig. 6, fig. 6 is a cross-sectional view of a power assembly according to an embodiment of the present application with a housing removed, a motor shaft 140 including a cylindrical inner coupling end 142, and an input shaft 310 including a slot-shaped outer coupling end 312. The outer circumferential surface of the outer coupling end 312 is used for fixedly connecting the inner ring 154 of the first bearing 150 and the inner ring 164 of the second bearing 160, and the inner circumferential surface of the outer coupling end 312 is used for driving and connecting the outer circumferential surface of the inner coupling end 142.

Referring to fig. 7, fig. 7 is an enlarged partial area schematic view of the powertrain shown in fig. 6, wherein the inner peripheral surface of the out-coupling end 312 includes a first groove 3122, and the outer peripheral surface of the in-coupling end 142 includes a second groove 1422, and the first groove 3122 and the second groove 1422 are configured to receive the stop collar 190. In other words, the limiting ring 190 is sleeved on the inner coupling end 142, and the limiting ring 190 is accommodated in the first groove 3122 and the second groove 1422. The stop collar 190 serves to limit axial sliding movement between the motor shaft 140 and the input shaft 310.

In the working process of the power assembly, the motor shaft easily slides along the axial direction of the motor due to vibration, magnetic pulling force and the like, and the axial sliding of the motor shaft can cause the problems of noise, vibration and noise vibration harshness (Noise, vibration, harshness, NVH) and is a device in the power assembly. For example, the bearings and the like cause damage, affecting the reliability of the powertrain. Axial sliding may also be referred to as axial play.

The power assembly 10 provided by the application comprises the limiting ring 190, when the motor shaft 140 moves along the motor axial direction Y, the limiting ring 190 is propped against the side wall of the second groove 1422 to limit the axial sliding between the motor shaft 140 and the input shaft 310, thereby reducing the occurrence of NVH and improving the reliability of the power assembly 10.

In some embodiments of the present application, the stop collar 190 is an elastic collar, which can reduce the axial impact applied to the motor shaft 140, so as to further reduce the occurrence of NVH problems.

Along the motor axial direction Y, the outer circumferential surface of the inner coupling end 142 includes an outer cylindrical section 1423 and a spline section 1424. The outer cylindrical section 1423 is disposed through the inner race 154 of the first bearing 150. The outer cylindrical section 1423 is used to assist in supporting the input shaft 310. The outer cylindrical section 1423 has a radius greater than the radius of the spline section 1424, and the spline section 1424 is configured to spline-connect with the inner circumferential surface of the outer coupling end 312 to achieve a mechanical transmission between the inner coupling end 142 and the outer coupling end 312. The spline connection can also limit the relative rotation of the inner coupling end 142 and the outer coupling end 312 in the circumferential direction of the motor 100 while realizing the mechanical transmission between the inner coupling end 142 and the outer coupling end 312, thereby improving the transmission stability between the inner coupling end 142 and the outer coupling end 312.

When the motor shaft 140 rotates, the motor shaft 140 drives the input shaft 310 to rotate. In the motor axial direction Y, the spacing between the spline section 1424 and the end face of the inner coupling end 142 that faces the speed reducer 300 is smaller than the spacing between the outer cylindrical section 1423 and the end face of the inner coupling end 142 that faces the speed reducer 300. The spacing between the splined section 1424 and the end face of the inner coupling end 142 facing the speed reducer 300 may be equal to or greater than 0. The second recess 1422 is located on the spline section 1424 in a radial projection of the motor shaft 140, in other words, the second recess 1422 is located on the spline section 1424. The rotor 130, the first bearing 150, and the retainer ring 190 are arranged in this order in the motor axial direction Y.

Referring to fig. 7, in the motor axial direction Y, a distance between a side wall of the first groove 3122 facing the stator 110 and an end surface of the out-coupling end 312 facing the stator 110 is a first distance D1, and a distance between a side wall of the second groove 1422 facing the stator 110 and an end surface of the out-coupling end 312 facing the stator 110 is a second distance D2, wherein the first distance D1 is not smaller than the second distance D2. The powertrain illustrated in fig. 7 is a partial structural cross-section illustration of the motor shaft 140 when no axial sliding occurs, and the first distance D1 is equal to the second distance D2.

Referring to fig. 7 and 8, fig. 8 is an enlarged schematic view of a portion area I of fig. 7, and the first distance D1 is equal to the second distance D2 when the motor shaft 140 does not slide axially. In other words, the side wall of the first groove 3122 toward the side of the stator 110 projects in the motor radial direction R on the side wall of the second groove 1422 toward the side of the stator 110 projects in the motor radial direction R.

Referring to fig. 7 and fig. 9 in combination, fig. 9 is a cross-sectional view of a portion of a power assembly when the motor shaft of the present application moves axially along the direction of the speed reducer toward the motor, and since the outer ring 152 of the first bearing 150 is fixed on the housing 400, the first groove 3122 and the second groove 1422 may be dislocated when the motor shaft 140 slides axially along the direction of the speed reducer 300 toward the motor 100, and the first distance D1 is greater than the second distance D2.

The side wall of the first groove 3122 facing the stator 110 abuts against the stop collar 190, thereby limiting the axial sliding of the motor shaft 140 along the direction of the speed reducer 300 toward the motor 100.

The inner ring 174 of the third bearing 170 is fixed to the motor shaft 140, and the outer ring 172 of the third bearing 170 is fixed to the housing 400, so that if the motor shaft 140 axially slides along the speed reducer 300 toward the motor 100, impact is easily applied to the third bearing 170, and the third bearing 170 is easily damaged. In the present application, the axial sliding of the motor shaft 140 along the direction of the decelerator 300 toward the motor 100 is restricted by the stopper ring 190, thereby reducing the impact of the third bearing 170 positioned on the motor shaft 140. The impact on the third bearing 170 is reduced, so that the axial machining precision of the motor end cover 415 can be correspondingly reduced, the machining cost of the housing 400 is reduced, and the reliability of the housing 400 and the third bearing 170 is improved.

In some embodiments of the present application, the notch of the first groove 3122 faces the axis of the input shaft 310, and the notch of the second groove 1422 faces away from the axis of the motor shaft 140, facilitating the entry of the stop collar 190 into the first groove 3122 and the second groove 1422. It will be appreciated that the present application is not limited to the slots of the first grooves 3122 facing the axis of the input shaft 310 and the slots of the second grooves 1422 facing away from the axis of the input shaft 310, for example, in one possible implementation, the slots of the first grooves 3122 may be disposed away from the motor 100 in the motor axial direction Y, and the stop collar 190 may be partially received in the first grooves 3122 and the second grooves 1422.

In some embodiments of the application, the depth of the second recess 1422 is greater than the depth of the first recess 3122 in the motor radial direction R to accommodate a substantial portion of the stop collar 190 within the second recess 1422. It is to be understood that the present application is not limited to the depth of the second groove 1422 being not less than the depth of the first groove 3122, e.g., the depth of the first groove 3122 is equal to the depth of the second groove 1422.

In some embodiments of the application, the depth of the second recess 1422 is greater than one-half the thickness of the stop collar 190 in the motor radial direction R. In assembly, the stop collar 190 may be placed in the second recess 1422 before the inner coupling end 142 is inserted into the outer coupling end 312. Because the depth of the second groove 1422 is greater than one half of the thickness of the stop collar 190, the stop collar 190 with a thickness exceeding one half is accommodated in the second groove, and the stop collar 190 is not easy to separate from the second groove 1422 during the process of inserting the inner coupling end 142 into the outer coupling end 312, so that the smoothness of the process of inserting the inner coupling end 142 into the outer coupling end 312 is improved.

It will be appreciated that the depth of the second recess 1422 is greater than one-half the thickness of the stop collar 190, and that the depth of the first recess 3122 may be greater than one-half the thickness of the stop collar 190. Either the first recess 3122 is no greater than one-half the thickness of the stop collar 190 or the second recess 1422 is no greater than one-half the thickness of the stop collar 190, etc.

In some embodiments of the present application, the second groove 1422 is an annular groove disposed along the circumferential direction of the motor shaft 140, the first groove 3122 is an annular groove disposed along the circumferential direction of the input shaft 310, and the stop collar 190 may be a closed loop structure or an annular structure having an opening. It is understood that the second recess 1422 may not be an annular recess, and a portion of the stop collar 190 is received in the second recess 1422. The first groove 3122 may not be an annular groove, and a portion of the stop collar 190 may be received in the first groove 3122.

In some embodiments of the present application, referring again to fig. 6, in the motor axial direction Y, the length of the spline section 1424 is greater than the length of the outer cylindrical section 1423, and the length of the outer cylindrical section 1423 is greater than the length of the first bearing 150. The length of the spline section 1424 is greater than the length of the outer cylindrical section 1423, so that the spline connection length between the inner coupling end 142 and the outer coupling end 312 can be increased, and the transmission stability between the inner coupling end 142 and the outer coupling end 312 can be further improved.

The motor shaft 140 further includes a bearing connection end 144 and a rotor connection section 146, wherein two ends of the rotor connection section 146 are respectively connected to the bearing connection end 144 and the inner coupling end 142 of the motor shaft 140, and the rotor connection section 146 is fixedly connected to a rotor of the motor 100. The wave pad 180 and the third bearing 170 are sleeved on the bearing connecting end 144. The wave pad 180, the third bearing 170, and the rotor 130 are sequentially arranged in the motor axial direction Y. The diameter of one end of the rotor connecting section 146 is greater than the diameter of the bearing connecting end 144 of the motor shaft 140 and greater than the inner diameter of the inner race 174 of the third bearing 170, and the diameter of the other end of the rotor connecting section 146 is greater than the diameter of the inner coupling end 142 and greater than the inner diameter of the inner race 154 of the first bearing 150.

The length of the rotor connecting section 146 is less than or equal to the spacing of the first bearing 150 and the third bearing 170 in the machine axis Y. The diameter of one end of the rotor connection section 146 is greater than the diameter of the bearing connection end 144 of the motor shaft 140 and greater than the inner diameter of the inner race 174 of the third bearing 170 such that the rotor connection section 146 forms a first stop shoulder 1442 axially limiting the third bearing 170 toward the bearing connection end 144 of the motor shaft 140, reducing the likelihood of axial movement of the third bearing 170 relative to the motor shaft 140.

The other end of the rotor connecting section 146 has a diameter greater than the diameter of the inner coupling end 142 and greater than the inner diameter of the inner race 154 of the first bearing 150 such that the rotor connecting section 146 forms a limiting end face 1462. The limiting end surface 1462 is used to abut against an end surface of the outer coupling end 312 facing the motor 100, so as to limit the axial sliding of the motor shaft 140 along the motor 100 toward the reducer 300.

Since the input shaft 310 is axially fixed to the housing 400 by the first bearing 150, when the motor shaft 140 axially slides along the motor 100 toward the speed reducer 300, the position of the outer coupling end 312 in the axial direction of the motor 100, which faces the end face of the motor 100, is not changed, so that the motor shaft 140 is prevented from axially moving from the motor 100 toward the speed reducer 300.

In some embodiments of the present application, the input shaft 310 has a socket 3100 extending along the axial direction of the input shaft 310, the socket 3100 may extend through both ends of the input shaft 310 along the axial direction of the input shaft 310, and the socket 3100 may extend through only the coupling-out end 312 toward the end surface of the motor 100 along the axial direction of the input shaft 310. The inner circumferential surface of the outcoupling end 312 includes an inner cylindrical section 3123 and a spline section 3124. The radius of the inner cylindrical section 3123 is greater than the radius of the spline section 3124. The outer cylindrical section 1423 is received within the inner cylindrical section 3123. The inner cylindrical section 3123 is configured to be in clearance fit with the outer cylindrical section 1423 to provide additional support to the motor shaft 140. The splined section 3124 of the outer coupling end 312 is splined to the splined section 1424 of the inner coupling end 142 such that the motor shaft 140 can transfer torque to the input shaft 310 via the splines, thereby effecting a drive connection between the motor shaft and the input shaft 310.

The spline connection realizes mechanical transmission between the inner coupling end 142 and the outer coupling end 312, and the relative rotation of the inner coupling end 142 and the outer coupling end 312 in the circumferential direction of the motor 100 improves the transmission stability between the inner coupling end 142 and the outer coupling end 312. The spacing between spline section 3124 and the end face of outcoupling end 312 that faces toward motor 100 is greater than the spacing between the end faces of inner cylindrical section 3123 that face toward motor 100. The spacing between the end surfaces of the inner cylindrical segment 3123 facing the motor 100 may be 0.

The second groove 3122 is located on the splined section 3124 in a radial projection of the input shaft 310, i.e. the second groove 1422 is located on the splined section 3124. One of the splined section 3124 of the outer coupling end 312 and the splined section 1424 of the inner coupling end 142 includes an internal spline and the other of the splined section 3124 of the outer coupling end 312 and the splined section 1424 of the inner coupling end 142 includes an external spline, the internal spline being in mating connection with the external spline.

The input shaft 310 also includes a bearing connection end 314 and a gear connection section 316. The two ends of the gear connection section 316 are respectively used for connecting the bearing connection end 314 and the out-coupling end 312 of the input shaft 310, and the gear connection section 316 is used for driving and connecting at least one gear of the reducer 300. The gear connection section 316 may include at least one gear tooth for engagement with a corresponding gear.

The diameter of the gear connection section 316 is greater than the diameter of the bearing connection end 314 of the input shaft 310 and greater than the inner diameter of the inner race 164 of the second bearing 160, and the diameter of the gear connection section 316 is greater than the diameter of the out-coupling end 312 and less than the inner diameter of the inner race 154 of the first bearing 150; the gear connection section 316 has a length along the axial direction of the motor 100 that is less than or equal to the spacing of the first bearing 150 and the second bearing 160.

In some embodiments of the present application, the diameter of the end of the gear connection section 316 that interfaces with the bearing connection end 314 is greater than the diameter of the bearing connection end 314 of the input shaft 310 and greater than the inner diameter of the inner race 164 of the second bearing 160, and a second limiting shoulder 3162 is formed on the gear connection section 316. The second limiting shoulder 3162 abuts the second bearing 160, reducing the likelihood of movement of the second bearing 160 relative to the input shaft 310.

The diameter of the gear connecting section 316 is larger than the diameter of the outer coupling end 312 and smaller than the inner diameter of the inner ring 154 of the first bearing 150, and a third limiting shoulder 3164 is formed on the gear connecting section 316, and the third limiting shoulder 3164 abuts against the first bearing 150, so that the possibility of movement of the first bearing 150 relative to the input shaft 310 is reduced.

The diameter of the gear connecting section 316 between the second limiting shoulder 3162 and the third limiting shoulder 3164 is not limited in the present application. For example, the diameter of the gear connection segment 316 between the second spacing shoulder 3162 and the third spacing shoulder 3164 may be less than or equal to the inner diameter of the inner race 164 of the second bearing 160, and the diameter of the gear connection segment 316 between the second spacing shoulder 3162 and the third spacing shoulder 3164 may be less than or equal to the inner diameter of the inner race 174 of the third bearing 170.

It is to be understood that the terms such as "comprises" and "comprising," which may be used in this application, indicate the presence of the disclosed functions, operations or elements, and are not limited to one or more additional functions, operations or elements. In the present application, terms such as "comprising" and/or "having" may be construed to mean a particular feature, number, operation, constituent element, component, or combination thereof, but may not be construed to exclude the presence or addition of one or more other features, numbers, operations, constituent elements, components, or combination thereof.

Furthermore, in the present application, the expression "and/or" includes any and all combinations of the words listed in association. For example, the expression "a and/or B" may include a, may include B, or may include both a and B.

In the present application, expressions including ordinal numbers such as "first" and "second" and the like may modify each element. However, such elements are not limited by the above expression. For example, the above description does not limit the order and/or importance of the elements. The above description is only intended to distinguish one element from another element. For example, the first user device and the second user device indicate different user devices, although both the first user device and the second user device are user devices. Similarly, a first element could be termed a second element, and, similarly, a second element could be termed a first element, without departing from the scope of the present application.

When a component is referred to as being "connected" or "connected" to another component, it should be understood that: the component is not only directly connected or connected to other components, but there can also be another component between the component and the other components. On the other hand, where components are referred to as being "directly connected" or "directly accessed" to other components, it should be understood that there are no components between them.

The foregoing is merely illustrative of the present application, and the present application is not limited thereto, and any person skilled in the art will readily recognize that variations or substitutions are within the scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims (15)

1. The utility model provides a power assembly, its characterized in that, power assembly includes casing, motor, reduction gear, first bearing and spacing ring, the casing is used for fixing the stator of motor with the outer lane of first bearing, the motor shaft of motor includes cylindricality internal coupling end, the input shaft of reduction gear includes the external coupling end of flute profile, wherein:

The outer peripheral surface of the outer coupling end is used for fixedly connecting with the inner ring of the first bearing, and the inner peripheral surface of the outer coupling end is used for being in transmission connection with the outer peripheral surface of the inner coupling end;

The inner peripheral surface of the outer coupling end comprises a first groove, the outer peripheral surface of the inner coupling end comprises a second groove, and the first groove and the second groove are used for accommodating the limiting ring.

2. The powertrain of claim 1, wherein a notch of the first groove faces an axis of the input shaft and a notch of the second groove faces away from the axis of the motor shaft, the second groove having a depth greater than a depth of the first groove in a radial direction of the motor.

3. The locomotion assembly of claim 1, wherein the depth of at least one of the first groove or the second groove is greater than one half the thickness of the stop collar in the radial direction of the motor.

4. The powertrain of claim 1, wherein an inner circumferential surface of the out-coupling end includes an inner cylindrical section and a spline section along an axial direction of the motor, a radius of the inner cylindrical section is larger than a radius of the spline section, the spline section is for spline connection with the in-coupling end, a distance between an end surface of the spline section and an end surface of the out-coupling end facing the motor is larger than a distance between end surfaces of the inner cylindrical section facing the motor, and a radial projection of the first groove along the input shaft is located on the spline section.

5. The powertrain of claim 4, wherein a length of the spline section is greater than a length of the inner cylindrical section along the motor axis, the length of the inner cylindrical section being greater than a length of the first bearing.

6. The power assembly according to claim 1, wherein the outer peripheral surface of the inner coupling end includes an outer cylindrical section and a spline section along the motor axial direction, the radius of the outer cylindrical section is larger than that of the spline section, the spline section is used for spline connection with the inner peripheral surface of the outer coupling end, the distance between the spline section and the end surface of the inner coupling end facing the speed reducer is smaller than that between the end surfaces of the outer cylindrical section facing the speed reducer, and the second groove is located on the spline section along the radial projection of the motor shaft.

7. The powertrain of claim 6, wherein a length of the spline section is greater than a length of the outer cylindrical section along the motor axis, the length of the outer cylindrical section being greater than a length of the first bearing.

8. The powertrain of claim 1, wherein a spacing between a side wall of the first groove facing the stator side and an end face of the outcoupling end facing the stator side is not smaller than a spacing between a side wall of the second groove facing the stator side and an end face of the outcoupling end facing the stator side in an axial direction of the motor.

9. The powertrain of claim 1, further comprising a second bearing, the input shaft comprising a bearing connection end and a gear connection section, both ends of the gear connection section being for connecting the bearing connection end and the outcoupling end of the input shaft, respectively, wherein:

the shell is used for fixing the outer ring of the second bearing, the inner ring of the second bearing is used for being fixedly connected with the bearing connecting end of the input shaft, and the gear connecting section is used for being in transmission connection with at least one gear of the speed reducer.

10. The powertrain of claim 9, wherein a diameter of the gear connection section is greater than a diameter of a bearing connection end of the input shaft and greater than an inner diameter of an inner race of the second bearing, and a diameter of the gear connection section is greater than a diameter of the out-coupling end and less than an inner diameter of an inner race of the first bearing; and the length of the gear connecting section is smaller than or equal to the interval between the first bearing and the second bearing along the axial direction of the motor.

11. The powertrain of claim 10, wherein the housing includes an intermediate housing for securing an outer race of the first bearing and a reducer end cap for securing an outer race of the second bearing.

12. The powertrain of claim 1, comprising a third bearing, the motor shaft comprising a bearing connection end and a rotor connection section, both ends of the rotor connection section being respectively for connecting the bearing connection end and the in-coupling end of the motor shaft, the rotor connection section being for fixedly connecting a rotor of the motor, wherein:

The shell is used for fixing the outer ring of the third bearing, and the inner ring of the third bearing is used for fixedly connecting the bearing connecting end of the motor shaft.

13. The powertrain of claim 12, wherein a diameter of one end of the rotor connection section is greater than a diameter of a bearing connection end of the motor shaft and greater than an inner diameter of an inner race of the third bearing, a diameter of the other end of the rotor connection section is greater than a diameter of the inner coupling end and greater than an inner diameter of an inner race of the first bearing, and a length of the rotor connection section in the motor axial direction is less than or equal to a spacing of the first bearing and the third bearing.

14. The powertrain of claim 12, wherein the housing includes an intermediate housing for securing the outer race of the first bearing and a motor end cap including a bearing receiving groove for receiving the wave pad and the third bearing, the wave pad being arranged between a groove bottom of the bearing receiving groove and the third bearing.

15. An electric vehicle, characterized in that it comprises a vehicle body for fixing the powertrain, wheels and a powertrain according to any one of claims 1-14, which is connected to the wheels for driving the wheels.