Powertrain and electric vehicles

Abstract

The present application provides a powertrain and an electric vehicle, wherein the powertrain includes a drive motor and a reducer, wherein the reducer includes an input shaft, an intermediate shaft, and an output wheel, wherein the input shaft is used for transmission connection with the motor shaft of the drive motor, the outer peripheral surface of the input shaft is used for fixing the input wheel, and the outer peripheral surface of the intermediate shaft is used for fixing the intermediate driving wheel and the intermediate driven wheel. The input wheel is used for meshing with the intermediate driven wheel, and the intermediate driving wheel is used for meshing with the output wheel, and the intermediate driving wheel, the input wheel, and the rotor of the drive motor are arranged in sequence along the axial direction of the powertrain. The input wheel is arranged close to the rotor of the drive motor, so that the two input shaft bearings fixed at both ends of the input shaft are evenly distributed in force, which can reduce the deformation of the input shaft bearings, thereby facilitating the improvement of the NVH performance of the powertrain.

Description

Technical Field

[0001] The present application relates to the technical field of electric vehicles, and in particular to a powertrain and an electric vehicle. Background Art

[0002] The powertrain includes a reducer and a drive motor. The motor shaft of the drive motor is connected to the input shaft of the reducer. The two ends of the input shaft of the reducer are installed on the inner wall of the reducer cavity through two bearings. The input wheel fixed to the input shaft is used to engage the intermediate driven wheel of the reducer. Since the rotation of the input wheel will apply axial force to one of the two bearings of the input shaft, and the bearing at the end of the input shaft close to the input wheel bears the axial force applied by the intermediate driven wheel, the two bearings of the input wheel bear different axial forces, which will affect the reliability of the two ends of the input shaft and the inner wall of the reducer cavity and affect the NVH performance of the powertrain. Summary of the invention

[0003] The present application provides a powertrain and an electric vehicle, which improve the NVH performance of the powertrain by making the bearings at both ends of the input shaft of the reducer bear forces evenly.

[0004] In a first aspect, the present application provides a powertrain, which includes a drive motor and a reducer, wherein the reducer includes an input shaft, an intermediate shaft, and an output wheel, wherein the input shaft is used for transmission connection with the motor shaft of the drive motor, the outer circumference of the input shaft is used for fixing the input wheel, and the outer circumference of the intermediate shaft is used for fixing the intermediate driving wheel and the intermediate driven wheel. The input wheel is used for meshing with the intermediate driven wheel, and the intermediate driving wheel is used for meshing with the output wheel, and the intermediate driving wheel, the input wheel, and the rotor of the drive motor are arranged in sequence along the axial direction of the powertrain.

[0005] In the embodiment of the present application, the intermediate driving wheel, the input wheel and the rotor of the driving motor are arranged in sequence along the axial direction of the powertrain, so that the input wheel is arranged close to the rotor of the driving motor, so that when the driving motor is in the front state, whether the input wheel is a left-handed gear or a right-handed gear, the force distribution of the two input shaft bearings fixed at both ends of the input shaft is more balanced, so that the axial force and radial force received by the input shaft can be avoided from being concentrated on one input shaft bearing, the deformation of the input shaft bearing can be reduced, and the reliability of the reducer can be improved. The uniform force distribution of the two input shaft bearings fixed at both ends of the input shaft also makes the force transmitted to the housing of the powertrain by the two input shaft bearings more uniform, which is conducive to improving the NVH performance of the powertrain.

[0006] In one embodiment, the input wheel is a right-handed gear, and the intermediate driving wheel is a left-handed gear.

[0007] In the embodiment of the present application, the input wheel is a right-handed gear, the intermediate driven wheel meshing with the input wheel is a left-handed gear, the intermediate driving wheel is a left-handed gear, and the output wheel meshing with the intermediate driving wheel is a left-handed gear. The drive motor is arranged in front, and when the input wheel rotates right, according to the right-hand rule, the input shaft bearing at the left end of the input shaft mainly bears the axial force, while the input shaft bearing at the right end of the input shaft is closer to the position where the input wheel meshes with the intermediate driven wheel, so that the input shaft bearing at the right end of the input shaft is mainly subjected to the radial force from the intermediate driven wheel and the weight of the right-handed driving motor. The axial force and radial force received by the input shaft can be distributed by the two input shaft bearings at both ends, so that there is no need for a single input shaft bearing to mainly bear the axial force and radial force at the same time, so that the force of the two input shaft bearings of the input shaft is more balanced, avoiding excessive load on one end of the input shaft bearing causing deformation of the input shaft bearing, improving the reliability of the powertrain, and also helping to improve the NVH performance of the powertrain.

[0008] In one embodiment, the helix angle of the input wheel is greater than the helix angle of the intermediate driving wheel.

[0009] In the embodiment of the present application, during the operation of the reducer, the axial forces generated by the input wheel on the intermediate driven wheel and the output wheel on the intermediate driving wheel are in opposite directions, thereby generating axial forces in opposite directions on the intermediate shaft used to fix the intermediate driven wheel and the intermediate driving wheel. The torque of the input wheel in the reducer is small, and the torque of the output wheel is large. The larger the helix angle of the input wheel, the larger the axial component of the input wheel received by the intermediate driven wheel when the input wheel is connected to the intermediate driven wheel to generate the force. The smaller the helix angle of the intermediate driving wheel, the smaller the axial component of the output wheel received by the intermediate driving wheel when the intermediate driving wheel is connected to the output wheel to generate the force, thereby making the difference in the magnitude of the axial forces in opposite directions received by the intermediate driven wheel and the intermediate driving wheel smaller. When the intermediate driven wheel and the intermediate driving wheel transmit the force to the intermediate shaft, most of the axial forces received by the intermediate shaft can be offset, thereby making the axial forces received by the intermediate shaft bearings at both ends of the intermediate shaft smaller, making the force of the powertrain more balanced, and improving the NVH performance of the powertrain.

[0010] In the embodiment of the present application, the helix angle of the input wheel is relatively large, which can meet the transmission requirements of the input wheel at a high speed. After the input wheel transmits power to the intermediate driven wheel, the speeds of the intermediate shaft and the intermediate driving wheel are relatively low. The helix angle of the intermediate driving wheel is relatively small, which is also sufficient to meet the transmission requirements of the intermediate driving wheel at a relatively low speed.

[0011] In one embodiment, the helix angle of the input wheel is greater than or equal to 27° and less than or equal to 30°, and the helix angle of the intermediate driving wheel is greater than or equal to 17° and less than or equal to 20°.

[0012] In the embodiment of the present application, the helix angle of the input wheel is set to be greater than or equal to 27° and less than or equal to 30°, and the helix angle of the intermediate driving wheel is greater than or equal to 17° and less than or equal to 20°. The matching of the helix angles can offset most of the axial force of the input wheel received by the intermediate driven wheel and the axial force of the output wheel received by the intermediate driving wheel, so that the axial force received by the intermediate shaft and the intermediate shaft bearings at both ends is smaller, and the force of the powertrain is more balanced, which is beneficial to improving the NVH performance of the powertrain.

[0013] In the embodiment of the present application, the helix angle of the input wheel is greater than or equal to 27° and less than or equal to 30°, so that the helix angle of the input wheel will not be too large, thereby avoiding the load of the input wheel from being concentrated on the helix line of the tooth surface, reducing the generation of thermal corrosion and fatigue cracks on the tooth surface of the input wheel. In addition, gears with large helix angles are difficult to process. The helix angle of the intermediate driving wheel is greater than or equal to 17° and less than or equal to 20°, so that the helix angle of the intermediate driving wheel will not be too small, thereby avoiding uneven distribution of the load on the tooth surface of the intermediate driving wheel, aggravating the wear of the tooth surface, and increasing the transmission noise.

[0014] In one embodiment, the helix angle of the intermediate driven wheel is the same as the helix angle of the input wheel, so that the intermediate driven wheel can be better meshed with the input wheel, and the tooth surfaces of the intermediate driven wheel and the input wheel have a higher overlap when meshing, which is beneficial to the transmission of power.

[0015] In one embodiment, the helix angle of the output wheel is the same as the helix angle of the intermediate driving wheel, so that the output wheel can be better meshed with the intermediate driving wheel, and the tooth surfaces of the intermediate driving wheel and the output wheel have a higher overlap when meshing, which is beneficial to the transmission of power.

[0016] In one embodiment, the pressure angle of the intermediate driving wheel is greater than the pressure angle of the input wheel.

[0017] In the embodiment of the present application, the load on the output wheel of the reducer is the largest, so that when the intermediate driving wheel is connected to the output wheel, the intermediate driving wheel is subjected to a larger radial force component of the output wheel, and the pressure angle of the intermediate driving wheel is larger, so that the load capacity of the intermediate driving wheel is stronger, so that the intermediate driving wheel can withstand a larger radial force component from the output wheel and avoid the teeth of the intermediate driving wheel from breaking. The load on the input wheel is the smallest, and setting the pressure angle of the input wheel to a smaller value can also meet the load requirement of the input wheel.

[0018] In the embodiment of the present application, the pressure angle of the input wheel is relatively small, and the meshing end face overlap between the input wheel and the intermediate driven wheel can be relatively large, which is beneficial for making the input wheel have better NVH performance when rotating at high speed. Even when the pressure angle of the intermediate driving wheel is relatively large and the meshing overlap between the intermediate driving wheel and the output wheel is relatively small, which deteriorates the NVH, the overall NVH performance of the powertrain can still be better.

[0019] In one embodiment, the pressure angle of the input wheel is greater than or equal to 15.5° and less than or equal to 17.5°, and the pressure angle of the intermediate driving wheel is greater than or equal to 19.5° and less than or equal to 21.5°.

[0020] In the embodiment of the present application, the coordination between the pressure angle of the input wheel and the pressure angle of the intermediate driving wheel can offset a part of the radial force on the intermediate shaft bearings at both ends of the intermediate shaft while meeting the NVH performance, so that the radial force on the intermediate shaft and the two intermediate shaft bearings is smaller, making the force on the powertrain more balanced, which is beneficial to improving the NVH performance of the powertrain.

[0021] In the embodiment of the present application, the pressure angle of the input wheel is greater than or equal to 15.5° and less than or equal to 17.5°, and the pressure angle of the intermediate driving wheel is greater than or equal to 19.5° and less than or equal to 21.5°. In addition, the pressure angles of the input wheel and the intermediate driving wheel are not too large, so that the radial force of the input wheel and the output wheel meshing with the intermediate driving wheel on the intermediate shaft bearings at both ends of the intermediate shaft is relatively small, which is beneficial to improving the NVH performance of the powertrain.

[0022] In one embodiment, the pressure angle of the intermediate driven wheel is the same as the pressure angle of the input wheel, so that the tooth surfaces of the intermediate driven wheel have a higher overlap when meshing with the input wheel, which is beneficial to making the transmission process smoother and can also improve the NVH performance of the powertrain.

[0023] In one embodiment, the pressure angle of the output wheel is the same as the pressure angle of the intermediate driving wheel, so that the tooth surfaces of the intermediate driving wheel and the output wheel have a higher overlap when they are meshed, which is beneficial to making the transmission process smoother and can also improve the NVH performance of the powertrain.

[0024] In one embodiment, the powertrain further includes a differential, the housing of the differential is used to be fixed to the output wheel, and the half shaft of the differential is used to drive and connect the wheels of the electric vehicle. The housing of the differential, the output wheel, the input wheel and the rotor of the drive motor are arranged in sequence along the axial direction of the powertrain.

[0025] In the embodiment of the present application, the half shaft of the differential is used to drive the wheels of the electric vehicle, so that the power transmitted from the motor shaft of the drive motor can be transmitted to the wheels of the electric vehicle through the differential after two-stage reduction in the reducer.

[0026] In the embodiment of the present application, because the input wheel is arranged close to the rotor of the drive motor, the intermediate driven wheel meshing with the input wheel is also close to the drive motor and occupies the space of the output wheel close to the drive motor, so that the space on the side of the output wheel close to the drive motor is smaller, which is not conducive to the arrangement of the differential. Therefore, it is necessary to arrange the differential on the side of the output wheel away from the drive motor to make the differential arrangement more convenient, so that the housing of the differential, the output wheel, the input wheel and the rotor of the drive motor are arranged in sequence along the axial direction of the powertrain.

[0027] In one embodiment, the powertrain further includes two reducers and two drive motors, and along the axial direction of the powertrain, the two reducers are arranged between the two drive motors. In particular, along the axial direction of the powertrain, the two intermediate driving wheels of the two reducers are arranged between the two input wheels of the two reducers, and the spacing between the two input wheels is greater than the spacing between the two intermediate driving wheels.

[0028] In the embodiment of the present application, along the axial direction of the powertrain, the spacing between the two input wheels is greater than the spacing between the two middle driving wheels, so that in the dual-motor powertrain, the two input wheels are arranged close to the rotors of the two drive motors respectively, so that when the drive motor is placed in front or rear, the two input shaft bearings fixed at both ends of the two input shafts are evenly distributed, so that the axial force and radial force received by the two input shafts will not be concentrated on the same input shaft bearing, which can reduce the deformation of the input shaft bearing, so that the force transmitted to the housing of the powertrain by the two input shaft bearings is more uniform, which is conducive to improving the NVH performance of the powertrain. It also allows the two arrangements of the drive motor in front or the drive motor in the rear to share a set of reducer gear shafts, which is conducive to the normalization of powertrain products.

[0029] In one embodiment, the housing of the powertrain includes an intermediate housing, two reducers are arranged on both sides of the intermediate housing along the axial direction of the powertrain, the intermediate housing includes two side surfaces and an outer peripheral surface, the two side surfaces are oriented opposite to each other along the axial direction of the powertrain, the two side surfaces respectively include two reducer receiving grooves, the notches of the two reducer receiving grooves are oriented opposite to each other along the axial direction of the powertrain, and each reducer receiving groove is used to fix and accommodate multiple bearings of a reducer. The outer peripheral surface includes a receiving groove, a part of which is recessed along the radial direction of the powertrain toward the gap between the two input wheels of the two reducers, and the receiving groove is used to accommodate an electrical component, which is used to receive the DC power output by the power battery and to transmit the DC power to the motor controllers of the two drive motors respectively.

[0030] In an embodiment of the present application, the two side surfaces are oriented opposite to each other along the axial direction of the powertrain, and the two side surfaces respectively include two reducer accommodating grooves, and the notches of the two reducer accommodating grooves are opposite to each other along the axial direction of the powertrain. Each reducer accommodating groove is used to fix and accommodate multiple bearings and gear shaft structures of the reducer, so that the two drive motors can independently control the two wheels of the electric vehicle through the two reducers.

[0031] In the embodiment of the present application, since the two input wheels of the two reducers are respectively close to the two drive motors, there is a large gap between the two input wheels. In the embodiment of the present application, a part of the accommodating groove on the outer peripheral surface is recessed along the radial direction of the powertrain toward the gap between the two input wheels, so that the space between the two input wheels along the radial direction of the powertrain is fully utilized to form the accommodating groove, and the accommodating groove does not occupy too much space outside the housing of the powertrain. The space in the accommodating groove can be used to accommodate some electrical components, thereby saving space for arranging electrical components outside the housing of the powertrain, which is beneficial to reducing the overall volume of the powertrain, thereby facilitating the optimization of the layout of the powertrain in the vehicle.

[0032] In the embodiment of the present application, the receiving slot is used to receive the DC power output by the power battery and to transmit the DC power to the motor controllers of the two drive motors respectively, and the DC power is converted into AC power by the motor controllers, and the AC power is transmitted to the two drive motors to drive the two drive motors to operate. Among them, the receiving slot accommodates the electrical components in the motor controller, and the electrical components shared by the two motor controllers can be accommodated in the receiving slot of the intermediate housing, which makes full use of the gap between the two reducers, reduces the layout space of the motor controller, reduces the overall volume of the powertrain, and is conducive to the layout of the powertrain in the vehicle.

[0033] In one embodiment, a portion of the accommodating groove is recessed in the radial direction of the powertrain toward the gap between the two intermediate driven wheels of the two reducers.

[0034] In the embodiment of the present application, since the two input wheels of the two reducers are respectively close to the two driving motors, there is a large gap between the two intermediate driven wheels respectively meshed with the two input wheels. A part of the receiving groove is recessed along the radial direction of the powertrain toward the gap between the two intermediate driven wheels, so that the space of the two intermediate driven wheels of the two reducers along the radial direction of the powertrain is fully utilized by the receiving groove, so that the receiving groove has a larger space for accommodating electrical components, which is more conducive to reducing the volume of the motor controller, reducing the overall volume of the powertrain, and facilitating the layout of the powertrain in the vehicle.

[0035] In one embodiment, a portion of the accommodating groove is recessed in the radial direction of the powertrain toward the gap between the two output wheels of the two reducers.

[0036] In the embodiment of the present application, a portion of the accommodating groove is recessed along the radial direction of the powertrain toward the gap between the two output wheels of the two reducers, so that the gap between the two output wheels of the two reducers can be fully utilized by the accommodating groove, which is also beneficial for the accommodating groove to have a larger space to accommodate electrical components, so that more electrical components in the motor controller can be placed in the accommodating groove, which is beneficial for reducing the volume of the part of the motor controller arranged outside the intermediate shell, reducing the overall volume of the powertrain, and facilitating the layout of the powertrain in the whole vehicle.

[0037] In one embodiment, the intermediate housing also includes two circumferential plates, which are spaced apart along the circumference of the power assembly, each circumferential plate is fixedly connected to the outer side of the groove wall of the two reducer accommodating grooves, and the two circumferential plates are used to enclose the outer side of the groove wall of the two reducer accommodating grooves to form an accommodating groove.

[0038] In the embodiment of the present application, two circumferential plates are distributed at intervals along the circumference of the powertrain, and each circumferential plate is fixedly connected to the outer side of the groove wall of the two reducer receiving grooves, so that the groove wall of the two reducer receiving grooves can be reused to form a receiving groove, and the space of the two reducer receiving grooves along the radial direction of the powertrain is fully utilized, so that the formation of the receiving groove does not increase the space of the powertrain along the radial direction of the powertrain, and the receiving groove can accommodate electrical components, reduce the overall volume of the powertrain, and thus optimize the layout of the vehicle. The two circumferential plates are used to enclose the outer side of the groove wall of the two reducer receiving grooves to form a receiving groove, and can also improve the integration and strength of the intermediate housing, and improve the overall strength of the housing of the powertrain.

[0039] In one embodiment, the groove bottom of each reducer receiving groove includes an input shaft bearing groove and an output shaft bearing groove, wherein the input shaft bearing groove is used to fix an outer ring of an input shaft bearing, and an inner ring of an input shaft bearing is used to be fixed to the input shaft, and the output shaft bearing groove is used to fix an outer ring of an output shaft bearing, and an inner ring of an output shaft bearing is used to be fixed to the output shaft, and the output shaft is used to fix the output wheel. Wherein, the spacing between the notches of the output shaft bearing grooves of the groove bottoms of the two reducer receiving grooves along the axial direction of the power assembly is smaller than the spacing between the notches of the input shaft bearing grooves of the groove bottoms of the two reducer receiving grooves.

[0040] In the embodiment of the present application, the spacing between the notches of the output shaft bearing grooves of the groove bottoms of the two reducer receiving grooves along the axial direction of the power assembly is smaller than the spacing between the notches of the input shaft bearing grooves of the groove bottoms of the two reducer receiving grooves, and the spacing between the notches of the input shaft bearing grooves of the groove bottoms of the two reducer receiving grooves is larger, because the two input wheels are respectively close to the outsides of the two drive motors, so that the two input wheels and the groove bottoms of the reducer receiving grooves of the intermediate housing have more space to form the input shaft bearing grooves, which can make the notches of the input shaft bearing grooves of the groove bottoms of each reducer receiving groove closer to the drive motor side, so that the transmission of the two input wheels is more stable, which is conducive to the normal operation of the power assembly. The spacing between the notches of the output shaft bearing grooves of the groove bottoms of the two reducer receiving grooves is smaller, because the two output wheels are close to the inner sides of the two drive motors, so that the notches of the output shaft bearing grooves of the groove bottoms of the two reducer receiving grooves on the two sides of the intermediate housing are closer, and the intermediate housing has more axial space to accommodate the two output wheels with larger radii.

[0041] In one embodiment, the housing of the powertrain further includes two integrated housings, each of which includes a motor housing and a reducer housing, each motor housing is used to accommodate a stator and a rotor of a driving motor, each reducer housing is used to enclose a reducer accommodating cavity with a reducer accommodating groove of the intermediate housing, and each reducer accommodating cavity is used to accommodate a parallel shaft assembly of a reducer. The axial bottom wall of each reducer housing includes another input shaft bearing groove and another output shaft bearing groove, the other input shaft bearing groove is used to fix the outer ring of the other input shaft bearing, the inner ring of the other input shaft bearing is used to be fixed to the input shaft, the other output shaft bearing groove is used to fix the outer ring of the other output shaft bearing, the inner ring of the other output shaft bearing is used to be fixed to the output shaft, and the output shaft is used to fix the output wheel. The spacing between the notches of the other output shaft bearing groove of the axial bottom walls of the two reducer housings along the axial direction of the powertrain is smaller than the spacing between the notches of the other input shaft bearing groove of the axial bottom walls of the two reducer housings.

[0042] In the embodiment of the present application, the spacing between the notches of the other output shaft bearing groove of the axial bottom wall of the two reducer housings along the axial direction of the powertrain is smaller than the spacing between the notches of the other input shaft bearing groove of the axial bottom wall of the two reducer housings, and the spacing between the notches of the other input shaft bearing groove of the axial bottom wall of the two reducer housings is larger, because the two input wheels are respectively close to the outside of the two drive motors, so that the notches of the other output shaft bearing groove of the two integrated housings are relatively far away along the axial direction of the powertrain, so that the other output shaft bearing groove of the two integrated housings has more axial space to accommodate the two input wheels. The spacing between the notches of the other output shaft bearing groove of the axial bottom wall of the two reducer housings is smaller, because the two output wheels are respectively arranged away from the two drive motor sides, so that the notches of the other input shaft bearing groove of the two integrated housings are closer, thereby reducing the axial length of the two output shafts, and the two output shafts are shorter, so that the transmission of the two output wheels is more stable, which is conducive to the normal operation of the powertrain.

[0043] In a second aspect, the present application provides an electric vehicle, comprising a frame, a power battery and a power assembly as in the first aspect, wherein the frame is used to fix the power battery and the power assembly.

[0044] In the powertrain of the embodiment of the present application, the input wheel is arranged close to the rotor of the drive motor, so that the two input shaft bearings fixed at both ends of the input shaft are evenly distributed in force, so that the axial force and radial force on the input shaft can be avoided from being concentrated on one input shaft bearing, which can reduce the deformation of the input shaft bearing and improve the reliability of the reducer. The even distribution of the force on the two input shaft bearings fixed at both ends of the input shaft also makes the force transmitted by the input shaft bearing to the housing of the powertrain more uniform, which is conducive to improving the NVH performance of the powertrain. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the embodiments of the present application will be described below.

[0046] Figure 1 is a schematic diagram of an electric vehicle provided in an embodiment of the present application;

[0047] Figure 2 is a schematic diagram of a powertrain provided in an embodiment of the present application;

[0048] Figure 3 is a schematic diagram of a reducer provided in an embodiment of the present application;

[0049] Figure 4 is another schematic diagram of a reducer provided in an embodiment of the present application;

[0050] Figure 5is another schematic diagram of a reducer provided in an embodiment of the present application;

[0051] Figure 6 is a schematic diagram of the gear rotation direction provided in an embodiment of the present application;

[0052] Figure 7 is another schematic diagram of the gear rotation direction provided in an embodiment of the present application;

[0053] Figure 8 It is a schematic diagram of the helix angle and the pressure angle provided in the embodiment of the present application;

[0054] Fig. 9 is a schematic diagram of a powertrain provided by another embodiment of the present application;

[0055] Fig.10 is a schematic diagram of an intermediate housing provided by another embodiment of the present application;

[0056] Fig.11 is another schematic diagram of a powertrain provided in another embodiment of the present application;

[0057] Fig.12 is a cross-sectional view of a powertrain provided by another embodiment of the present application;

[0058] Fig.13 is another cross-sectional view of a powertrain provided in another embodiment of the present application;

[0059] Fig.14 is a cross-sectional view of an intermediate housing provided in another embodiment of the present application;

[0060] Fig.15 is a schematic diagram of an integrated housing provided by another embodiment of the present application;

[0061] Fig.16 It is a cross-sectional view of an integrated housing provided in another embodiment of the present application. DETAILED DESCRIPTION

[0062] The technical solutions in the embodiments of the present application will be described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments.

[0063] For ease of understanding, the English abbreviations and related technical terms involved in the embodiments of the present application are explained and described below.

[0064] Front drive motor: refers to the drive motor being arranged in front of the differential along the direction of vehicle travel in the overall vehicle layout.

[0065] Rear drive motor: refers to the drive motor being arranged behind the differential along the direction of vehicle travel in the overall vehicle layout.

[0066] NVH: It is the abbreviation of Noise, Vibration and Harshness, which refers to noise, vibration and acoustic roughness.

[0067] The present application provides a powertrain including a drive motor and a reducer, wherein the reducer includes an input shaft, an intermediate shaft and an output wheel, wherein the input shaft is used for transmission connection with the motor shaft of the drive motor, the outer peripheral surface of the input shaft is used for fixing the input wheel, and the outer peripheral surface of the intermediate shaft is used for fixing the intermediate driving wheel and the intermediate driven wheel. Among them, the input wheel is used to mesh with the intermediate driven wheel, and the intermediate driving wheel is used to mesh with the output wheel, and the intermediate driving wheel, the input wheel and the rotor of the drive motor are arranged in sequence along the axial direction of the powertrain. The input wheel is arranged close to the rotor of the drive motor, so that the force distribution of the two input shaft bearings fixed at both ends of the input shaft is uniform, so that the axial force and radial force on the input shaft can be avoided from being concentrated on one input shaft bearing, the deformation of the input shaft bearing can be reduced, and the reliability of the reducer can be improved. The uniform force distribution of the two input shaft bearings fixed at both ends of the input shaft also makes the force transmitted to the housing of the powertrain by the input shaft bearing more uniform, which is conducive to improving the NVH performance of the powertrain.

[0068] Figure 1 is a schematic diagram of an electric vehicle 1 provided in an embodiment of the present application, Figure 2 It is a schematic diagram of a powertrain 10 provided in an embodiment of the present application.

[0069] In one embodiment, the electric vehicle 1 includes a powertrain 10, a frame 20, a power battery 30 and wheels 40. Figure 1 As shown, the power battery 30 and the power assembly 10 are fixed to the frame 20. In the embodiment of the present application, the electric vehicle 1 refers to a wheeled device driven or towed by a power device. In the embodiment of the present application, the power battery 30 supplies power to the power assembly 10, and the power assembly 10 drives the wheels 40.

[0070] In one embodiment, if Figure 2 As shown, the powertrain 10 includes a motor controller 100, a drive motor 200 and a reducer 300. In the embodiment of the present application, the motor controller 100 is electrically connected to the drive motor 200, and the motor controller 100 is used to receive the high-voltage direct current delivered by the power battery 30, and convert the high-voltage direct current into high-voltage alternating current and deliver it to the drive motor 200 to drive the drive motor 200 to rotate. The drive motor 200 is transmission-connected to the reducer 300, and the drive motor 200 drives the reducer 300 to rotate. In one embodiment, the powertrain 10 may not include the motor controller 100, and the powertrain 10 includes the drive motor 200 and the reducer 300.

[0071] In the embodiment of the present application, the drive motor 200 includes a motor shaft 210, a motor stator (not shown) and a motor rotor 220. The gear shaft structure of the reducer 300 includes an input shaft 310, an intermediate shaft 320, an output shaft 370 and a plurality of bearings 380. The input shaft 310, the intermediate shaft 320 and the output shaft 370 are each rotatably connected to the inner wall of the reducer cavity through two bearings 380. The outer peripheral surface of the input shaft 310 is used to fix the input wheel 340, and the outer peripheral surface of the intermediate shaft 320 is used to fix the intermediate driving wheel 350 and the intermediate driven wheel 360. Among them, the input wheel 340 is used to mesh with the intermediate driven wheel 360, and the intermediate driving wheel 350 is used to mesh with the output wheel 330. In the drive motor 200, the motor rotor 220 is fixedly sleeved on the motor shaft 210. After receiving the alternating current, the motor stator drives the motor rotor 220 to rotate, thereby driving the motor shaft 210 to rotate. The motor shaft 210 of the driving motor 200 is drivingly connected to the input shaft 310 of the reducer 300 . The input shaft 310 receives the power transmitted by the motor shaft 210 of the driving motor 200 and transmits the power to the output shaft 370 through the gear assembly to drive the wheels 40 of the electric vehicle 1 to travel.

[0072] The motor shaft of the drive motor is connected to the input shaft of the reducer. The two ends of the input shaft of the reducer are installed on the inner wall of the reducer cavity through two input shaft bearings. The input wheel fixed to the input shaft is used to engage the intermediate driven wheel of the reducer. Since the rotation of the input wheel will apply axial force to one of the two input shaft bearings of the input shaft, and the input shaft bearing at one end of the input shaft close to the input wheel bears the axial force applied by the intermediate driven wheel, the axial forces borne by the two input shaft bearings of the input wheel are different, which will affect the reliability of the two ends of the input shaft and the inner wall of the reducer cavity and affect the NVH performance of the powertrain.

[0073] In the embodiment of the present application, the intermediate driving wheel, the input wheel and the rotor of the driving motor are arranged in sequence along the axial direction of the powertrain, so that the forces on the input shaft bearings at both ends of the input shaft are more balanced, so that the axial force and radial force on the input shaft can be avoided from being concentrated on one input shaft bearing, which can reduce the deformation of the input shaft bearing and improve the reliability of the reducer. The even distribution of the forces on the two input shaft bearings fixed at both ends of the input shaft also makes the forces transmitted from the input shaft bearings to the housing of the powertrain more even, which is conducive to improving the NVH performance of the powertrain.

[0074] The powertrain 10 provided in an embodiment of the present application will be described in detail below.

[0075] Figure 3 is a schematic diagram of a reducer 300 provided in an embodiment of the present application, Figure 4 is another schematic diagram of the reducer 300 provided in the embodiment of the present application, Figure 5It is another schematic diagram of the reducer 300 provided in an embodiment of the present application.

[0076] In one embodiment, if Figures 2 to 4 As shown, a power assembly 10 includes a driving motor 200 and a reducer 300, wherein the reducer 300 includes an input shaft 310, an intermediate shaft 320, and an output wheel 330. The input shaft 310 is used for transmission connection with the motor shaft 210 of the driving motor 200, the outer circumference of the input shaft 310 is used for fixing the input wheel 340, and the outer circumference of the intermediate shaft 320 is used for fixing the intermediate driving wheel 350 and the intermediate driven wheel 360. Among them, the input wheel 340 is used for meshing with the intermediate driven wheel 360, and the intermediate driving wheel 350 is used for meshing with the output wheel 330. Along the axial direction O of the power assembly 10, the intermediate driving wheel 350, the input wheel 340, and the rotor 220 of the driving motor 200 are arranged in sequence.

[0077] In the embodiment of the present application, the input wheel 340 is used to engage the intermediate driven wheel 360, and the intermediate driving wheel 350 is used to engage the output wheel 330, so that the intermediate driven wheel 360 can receive power from the input wheel 340, and the intermediate driving wheel 350 can transmit power to the output wheel 330, thereby realizing a two-stage reduction in speed of the reducer 300.

[0078] In the embodiment of the present application, the plurality of bearings 380 include two input shaft bearings 512a, 621a, and the input shaft 310 is rotatably connected to the inner wall of the reducer cavity (not shown) through the two input shaft bearings 512a, 621a.

[0079] In the embodiment of the present application, the intermediate driving wheel 350 , the input wheel 340 and the rotor 220 of the drive motor 200 are arranged in sequence along the axial direction O of the powertrain 10 , so that the input wheel 340 is arranged close to the rotor 220 of the drive motor 200 .

[0080] like Figure 3 As shown, the drive motor 200 is arranged on the right side of the reducer 300, and the input wheel 340 is arranged close to the rotor 220 of the drive motor 200, wherein the input shaft bearing 621a is arranged close to the drive motor 200, and the input shaft bearing 512a is arranged away from the drive motor 200. Since the input shaft bearing 621a is closer to the drive motor 200 than the input shaft bearing 512a, the input shaft bearing 621a has a larger load. The input shaft bearing 621a is closer to the input wheel 340, and the input wheel 340 is used to engage the intermediate driven wheel 360, so that the input shaft bearing 621a has a larger load than the input shaft bearing 512a. And the input wheel 340 also needs to bear the radial force applied by the intermediate driven wheel 360, so that the force applied to the input shaft bearing 621a is greater than that of the input shaft bearing 512a. As shown Figure 3 As shown, Figure 3The upper side is the wheel forward direction. When the drive motor 200 is in the front position, the input wheel 340 is a right-hand gear. When the power assembly 10 is working, the input wheel 340 is in the right-hand direction. Figure 3 The input wheel 340 rotates upward, so that the input shaft 310 generates an axial force F1 to the left, thereby causing the axial force F1 to act on the Figure 3 The input shaft bearing 512a on the left side makes the difference in force acting on the input shaft bearings 621a and 512a at both ends of the input shaft 310 smaller, thereby avoiding excessive load on one end of the input shaft bearing 621a or the input shaft bearing 512a, which may cause deformation of the input shaft bearing 621a or the input shaft bearing 512a.

[0081] like Figure 5 As shown, the drive motor 200 is arranged on the left side of the reducer 300, and the input wheel 340 is arranged close to the rotor 220 of the drive motor 200, wherein the input shaft bearing 621a is arranged close to the drive motor 200, and the input shaft bearing 512a is arranged away from the drive motor 200. Since the input shaft bearing 621a is closer to the input wheel 340 and the drive motor 200, and the input wheel 340 is used to mesh with the intermediate driven wheel 360, the input shaft bearing 621a has a greater load than the input shaft bearing 512a, and the input wheel 340 also needs to bear the radial force applied by the intermediate driven wheel 360, so that the input shaft bearing 621a is subjected to a greater force than the input shaft bearing 512a. Figure 5 As shown, Figure 5 The upper side is the wheel forward direction. When the drive motor 200 is placed in front, the input wheel 340 is a left-hand gear. When the power assembly 10 is working, the input wheel 340 is facing Figure 5 The input wheel 340 rotates upward, causing the input shaft 310 to generate an axial force F2 to the right, thereby causing the axial force F2 to act on the Figure 5 The input shaft bearing 512a on the middle right side makes the difference in force acting on the input shaft bearing 512a and the input shaft bearing 621a at both ends of the input shaft 310 smaller, thereby avoiding excessive load on one end of the input shaft bearing 512a or the input shaft bearing 621a, which may cause deformation of the input shaft bearing 512a or the input shaft bearing 621a.

[0082] In the embodiment of the present application, the intermediate driving wheel 350, the input wheel 340 and the rotor 220 of the drive motor 200 are arranged in sequence along the axial direction O of the power assembly 10, so that the input wheel 340 is arranged close to the rotor 220 of the drive motor 200, so that when the drive motor 200 is in the front state, whether the input wheel 340 is a left-handed gear or a right-handed gear, the force distribution of the two input shaft bearings 512a, 621a fixed at both ends of the input shaft 310 is more balanced, so that the axial force and radial force received by the input shaft 310 can be avoided from being concentrated on one input shaft bearing 512a or the input shaft bearing 621a, and the deformation of the two input shaft bearings 512a, 621a can be reduced, and the reliability of the reducer 300 is improved. The uniform force distribution of the two input shaft bearings 512a, 621a fixed at both ends of the input shaft 310 also makes the force transmitted to the housing of the power assembly 10 by the two input shaft bearings 512a, 621a more uniform, which is conducive to improving the NVH performance of the power assembly 10.

[0083] in, Figure 3 and Figure 4 The input shaft 310 and the intermediate shaft 320 are only schematic positions and do not represent specific structures.

[0084] In one embodiment, the intermediate driving wheel 350, the input wheel 340, and the rotor 220 of the drive motor 200 are arranged in sequence along the axial direction O of the power assembly 10, so that the NVH performance of the power assembly 10 is better when the drive motor 200 is placed in front and the drive motor 200 is placed in the rear. Compared with the arrangement of the input wheel 340 away from the rotor 220 of the drive motor 200, that is, the input wheel 340, the intermediate driving wheel 350, and the rotor 220 of the drive motor 200 are arranged in sequence along the axial direction O of the power assembly 10, the present application Figure 3 Drive motor 200 front and Figure 4 The NVH performance of the rear-mounted powertrain 10 with the drive motor 200 is better.

[0085] Figure 6 is a schematic diagram of the gear rotation direction provided in the embodiment of the present application, Figure 7 is another schematic diagram of the gear rotation direction provided in the embodiment of the present application. Figure 6 As shown in the figure, a right-handed gear refers to a gear whose helical line S extends to the upper right corner when the helical gear is placed vertically along the axis direction; Figure 7 As shown, a left-handed gear refers to a gear in which the helical line S extends to the upper left corner when the helical gear is placed vertically along the axial direction.

[0086] In one embodiment, if Figure 3 to Figure 4 As shown, the input wheel 340 is a right-handed gear, and the intermediate driving wheel 350 is a left-handed gear.

[0087] In the embodiment of the present application, the input wheel 340 is a right-handed gear, the intermediate driven wheel 360 meshing with the input wheel 340 is a left-handed gear, the intermediate driving wheel 350 is a left-handed gear, and the output wheel 330 meshing with the intermediate driving wheel 350 is a left-handed gear. Figure 3 As shown, the drive motor 200 is arranged in front. When the input wheel 340 rotates right, according to the right-hand rule, the input shaft bearing 512a at the left end of the input shaft 310 mainly bears the axial force F1, while the input shaft bearing 621a at the right end of the input shaft 310 is closer to the position where the input wheel 340 meshes with the intermediate driven wheel 360, so that the input shaft bearing 621a at the right end of the input shaft 310 is mainly subjected to the radial force from the intermediate driven wheel 360 and the weight of the right-hand drive motor 200. The axial force and radial force on the input shaft 310 are The axial force can be distributed by the two input shaft bearings 512a and 621a at both ends, so that there is no need for a single bearing 380 to bear the axial force and the radial force at the same time, so that the force on the two input shaft bearings 512a and 621a of the input shaft 310 is more balanced, avoiding excessive load on one end of the input shaft bearing 512a or the input shaft bearing 621a, which may cause the input shaft bearing 512a or the input shaft bearing 621a to deform, thereby improving the reliability of the powertrain 10 and also helping to improve the NVH performance of the powertrain 10.

[0088] In the embodiments of the present application, Figure 3 As shown, when the drive motor 200 is arranged in front and the input wheel 340 is a right-handed gear, the NVH performance of the powertrain 10 during operation is better than when the input wheel 340 is a left-handed gear. Figure 3 As shown, in the embodiment of the present application, the multiple bearings 380 also include two intermediate shaft bearings 514a, 623a, and the intermediate shaft 320 is rotatably connected to the inner wall of the reducer cavity through the two intermediate shaft bearings 514a, 623a. The intermediate shaft bearing 623a is close to the intermediate driven wheel 360, and the intermediate shaft bearing 514a is close to the intermediate driving wheel 350. When the drive motor 200 is arranged in the front and the input wheel 340 is a right-handed gear, the axial force F3 generated by the input wheel 340 on the intermediate shaft 320 during the transmission between the input wheel 340 and the intermediate driven wheel 360 is directed to the right, and the axial force F4 generated by the output wheel 330 on the intermediate shaft 320 during the transmission between the intermediate driving wheel 350 and the output wheel 330 is directed to the left. The axial force F3 and the axial force F4 are in opposite directions, so that the axial forces F3 and F4 received by the intermediate shaft 320 during the operation of the reducer 300 can be mostly offset, thereby reducing the axial force received by the intermediate shaft 320, and further reducing the axial force transmitted by the intermediate shaft bearings 514a and 623a fixed to the intermediate shaft 320 from the intermediate shaft 320, thereby reducing the force transmitted by the intermediate shaft bearings 514a and 623a to the housing of the powertrain 10, thereby improving the NVH performance of the powertrain 10.

[0089] in, Figure 3 and Figure 5 The middle arrow indicates the direction of the axial force generated when the reducer 300 is working.

[0090] Figure 8 is a schematic diagram of the helix angle α and the pressure angle β provided in the embodiment of the present application. Figure 8 As shown, the helix angle is denoted as α, and the helix angle α refers to the acute angle between the tangent line of the cylindrical helix S and the straight generatrix of the cylindrical surface passing through the tangent point. In one embodiment, the test method of the helix angle α is as follows: Figure 8 As shown, the outer circumferential surface of the gear 700 includes a plurality of teeth 710. The outer circumferential surface of the gear 700 is flattened to obtain a plane N. The circumferential direction of the gear 700 is flattened to form a first direction B. The normal plane E of each tooth 710 is perpendicular to the extension direction of the tooth 710. The angle between the intersection line D1 of the normal plane E of each tooth 710 and the plane N and the first direction B is the helix angle α. Another method for testing the helix angle α is as follows: the angle between the helix line S on the plane N and the axial direction O is the helix angle α.

[0091] In one embodiment, the helix angle α of the input wheel 340 is greater than the helix angle α of the intermediate driving wheel 350 .

[0092] In the embodiment of the present application, during the operation of the reducer 300, Figure 3 , Figure 4 and Figure 8 As shown, the axial forces generated by the input wheel 340 on the intermediate driven wheel 360 and the output wheel 330 on the intermediate driving wheel 350 are in opposite directions, thereby generating axial forces in opposite directions on the intermediate shaft 320 used to fix the intermediate driven wheel 360 and the intermediate driving wheel 350. In the reducer 300, the torque of the input wheel 340 is small, and the torque of the output wheel 330 is large. The helix angle α of the input wheel 340 is large, which is conducive to making the axial component of the input wheel 340 received by the intermediate driven wheel 360 larger when the input wheel 340 is connected to the intermediate driven wheel 360 to generate a force. The helix angle α of the intermediate driving wheel 350 is relatively small, which is beneficial for the intermediate driving wheel 350 to receive a smaller axial component of the output wheel 330 when the intermediate driving wheel 350 is connected to the output wheel 330 to generate a force, thereby making the difference in magnitude of the axial forces in opposite directions received by the intermediate driven wheel 360 and the intermediate driving wheel 350 relatively small. When the intermediate driven wheel 360 and the intermediate driving wheel 350 transmit the force to the intermediate shaft 320, most of the axial forces received by the intermediate shaft 320 can be offset, thereby making the axial forces received by the intermediate shaft bearings 514a and 623a at both ends of the intermediate shaft 320 smaller, making the force on the powertrain 10 more balanced, and improving the NVH performance of the powertrain 10.

[0093] In the embodiment of the present application, the helix angle α of the input wheel 340 is relatively large, which can meet the transmission requirements of the input wheel 340 at a high speed. After the input wheel 340 transmits power to the intermediate driven wheel 360, the rotation speeds of the intermediate shaft 320 and the intermediate driving wheel 350 are relatively low. The helix angle α of the intermediate driving wheel 350 is relatively small, which is also sufficient to meet the transmission requirements of the intermediate driving wheel 350 at a relatively low speed.

[0094] In one embodiment, the helix angle α of the input wheel 340 is greater than or equal to 27° and less than or equal to 30°, and the helix angle α of the intermediate driving wheel 350 is greater than or equal to 17° and less than or equal to 20°.

[0095] In the embodiments of the present application, Figure 3 , Figure 4 and Figure 8 As shown, the helix angle α of the input wheel 340 is set to be greater than or equal to 27° and less than or equal to 30°, and the helix angle α of the intermediate driving wheel 350 is greater than or equal to 17° and less than or equal to 20°. The matching of the sizes of the helix angles α of the two can make the axial force of the input wheel 340 on the intermediate driven wheel 360 and the axial force of the output wheel 330 on the intermediate driving wheel 350 mostly offset, so that the axial force on the intermediate shaft 320 and the intermediate shaft bearings 514a and 623a at both ends is smaller, so that the force on the powertrain 10 is more balanced, which is beneficial to improving the NVH performance of the powertrain 10.

[0096] In the embodiment of the present application, the helix angle α of the input wheel 340 is greater than or equal to 27° and less than or equal to 30°, so that the helix angle α of the input wheel 340 will not be too large, thereby avoiding the load of the input wheel 340 from being concentrated on the helix line of the tooth surface, reducing the thermal corrosion and fatigue cracks on the tooth surface of the input wheel 340. In addition, the gear processing difficulty is large for a large helix angle α. The helix angle α of the intermediate driving wheel 350 is greater than or equal to 17° and less than or equal to 20°, so that the helix angle α of the intermediate driving wheel 350 will not be too small, thereby avoiding uneven distribution of the load on the tooth surface of the intermediate driving wheel 350, aggravating the wear of the tooth surface, and increasing the transmission noise.

[0097] In one embodiment, the helix angle α of the input wheel 340 is equal to 28°, and the helix angle α of the intermediate driving wheel 350 is equal to 18°.

[0098] In one embodiment, the helix angle α of the intermediate driven wheel 360 is the same as the helix angle α of the input wheel 340. This allows the intermediate driven wheel 360 to be better meshed with the input wheel 340, so that the tooth surfaces of the intermediate driven wheel 360 and the input wheel 340 have a higher overlap when meshing, which is beneficial to the transmission of power.

[0099] In one embodiment, the helix angle α of the output wheel 330 is the same as the helix angle α of the intermediate driving wheel 350. This allows the output wheel 330 to be better meshed with the intermediate driving wheel 350, so that the tooth surfaces of the intermediate driving wheel 350 have a higher overlap when meshing with the output wheel 330, which is beneficial to the transmission of power.

[0100] like Figure 8 As shown, the pressure angle is denoted as β, which refers to the angle between the tooth profile and the radial line in the gear normal surface. The test method of pressure angle β is as follows: Figure 8 As shown, the outer circumferential surface of the gear 700 includes a plurality of teeth 710. The outer circumferential surface of the gear 700 is flattened to obtain a plane N. The normal plane E of each tooth 710 is perpendicular to the extension direction of the tooth 710. The tooth profile of each tooth 710 on the normal plane E is recorded as D2. The radial line of the tooth 710 is recorded as D3. The direction R of the radial line D3 is perpendicular to the plane N. The angle between the tooth profile D2 and the radial line D3 is the pressure angle β.

[0101] In one embodiment, the pressure angle β of the intermediate driving wheel 350 is greater than the pressure angle β of the input wheel 340 .

[0102] In the embodiments of the present application, Figure 3 , Figure 4 and Figure 8 As shown, the load of the output wheel 330 in the reducer 300 is the largest, so that when the intermediate driving wheel 350 is connected to the output wheel 330, the intermediate driving wheel 350 is subjected to a larger radial force of the output wheel 330. The pressure angle β of the intermediate driving wheel 350 is set larger, so that the load capacity of the intermediate driving wheel 350 is stronger, so that the intermediate driving wheel 350 can withstand a larger radial force from the output wheel 330 and avoid the teeth of the intermediate driving wheel 350 from being broken. The load of the input wheel 340 is the smallest, and the load requirement of the input wheel 340 can be met by setting the pressure angle β of the input wheel 340 to be smaller.

[0103] In the embodiment of the present application, the pressure angle β of the input wheel 340 is relatively small, and the meshing end face overlap between the input wheel 340 and the intermediate driven wheel 360 can be relatively large, which is beneficial for the input wheel 340 to have better NVH performance when rotating at high speed. When the pressure angle β of the intermediate driving wheel 350 is relatively large and the meshing overlap between the intermediate driving wheel 350 and the output wheel 330 is relatively small, which deteriorates the NVH, the overall NVH performance of the powertrain 10 can also be improved.

[0104] In one embodiment, the pressure angle β of the input wheel 340 is greater than or equal to 15.5° and less than or equal to 17.5°, and the pressure angle β of the intermediate driving wheel 350 is greater than or equal to 19.5° and less than or equal to 21.5°.

[0105] In the embodiments of the present application, Figure 3 , Figure 4 and Figure 8 As shown, the coordination between the pressure angle β of the input wheel 340 and the pressure angle β of the intermediate driving wheel 350 can offset a part of the radial force on the intermediate shaft bearings 514a and 623a at both ends of the intermediate shaft 320 while meeting the NVH requirements, so that the radial force on the intermediate shaft 320 and the two intermediate shaft bearings 514a and 623a is smaller, making the force on the powertrain 10 more balanced, which is beneficial to improving the NVH performance of the powertrain 10.

[0106] In the embodiment of the present application, the pressure angle β of the input wheel 340 is greater than or equal to 15.5° and less than or equal to 17.5°, and the pressure angle β of the intermediate driving wheel 350 is greater than or equal to 19.5° and less than or equal to 21.5°. In addition, the pressure angles β of the input wheel 340 and the intermediate driving wheel 350 are not too large, so that the radial forces of the input wheel 340 and the output wheel 330 meshing with the intermediate driving wheel 350 on the intermediate shaft bearings 514a and 623a at both ends of the intermediate shaft 320 are relatively small, which is beneficial to improving the NVH performance of the powertrain 10.

[0107] In one embodiment, the pressure angle β of the input wheel 340 is equal to 16°, and the pressure angle β of the intermediate driving wheel 350 is equal to 20°.

[0108] In one embodiment, the pressure angle β of the intermediate driven wheel 360 is the same as the pressure angle β of the input wheel 340, so that the tooth surfaces of the intermediate driven wheel 360 have a higher overlap when meshing with the input wheel 340, which is beneficial to making the transmission process smoother and can also improve the NVH performance of the powertrain 10.

[0109] In one embodiment, the pressure angle β of the output wheel 330 is the same as the pressure angle β of the intermediate driving wheel 350, so that the tooth surfaces of the intermediate driving wheel 350 have a higher overlap when meshing with the output wheel 330, which is conducive to making the transmission process smoother and can also improve the NVH performance of the powertrain 10.

[0110] In one embodiment, if Figures 2 to 4 As shown, the power assembly 10 further includes a differential 400, a housing 410 of the differential 400 is used to be fixed to the output wheel 330, and a half shaft 50 of the differential 400 is used to drive and connect the wheel 40 of the electric vehicle 1. Among them, along the axial direction O of the power assembly 10, the housing 410 of the differential 400, the output wheel 330, the input wheel 340 and the rotor 220 of the drive motor 200 are arranged in sequence.

[0111] In the embodiment of the present application, the half shaft 50 of the differential 400 is used to transmit and connect the wheels 40 of the electric vehicle 1, so that the power transmitted from the motor shaft 210 of the drive motor 200 can be transmitted to the wheels 40 of the electric vehicle 1 through the differential 400 after two-stage reduction in speed by the reducer 300.

[0112] In the embodiment of the present application, because the input wheel 340 is arranged close to the rotor 220 of the drive motor 200, the intermediate driven wheel 360 meshing with the input wheel 340 is also close to the drive motor 200 and occupies the space of the output wheel 330 close to the drive motor 200, so that the space on the side of the output wheel 330 close to the drive motor 200 is smaller, which is not conducive to the arrangement of the differential 400. Therefore, it is necessary to arrange the differential 400 on the side of the output wheel 330 away from the drive motor 200, so that the arrangement of the differential 400 is more convenient, so that the housing 410 of the differential 400, the output wheel 330, the input wheel 340 and the rotor 220 of the drive motor 200 are arranged in sequence along the axial direction O of the powertrain 10.

[0113] In one embodiment, the half shaft 50 of the differential 400 is coaxial with the output shaft 370 of the reducer 300. In one embodiment, the half shaft 50 of the differential 400 is drivingly connected to the output shaft 370 of the reducer 300.

[0114] Fig. 9 It is a schematic diagram of a powertrain 10 provided in another embodiment of the present application.

[0115] In one embodiment, if Fig. 9As shown, the power assembly 10 further includes two reducers 300 and two drive motors 200, the two reducers 300 are respectively denoted as reducers 300a and reducers 300b, and the two drive motors 200 are respectively denoted as drive motors 200a and drive motors 200b. Along the axial direction O of the power assembly, the reducers 300a and 300b are arranged between the drive motors 200a and 200b, and the reducer 300b includes an input shaft 310b, an intermediate shaft 320b and an output wheel 330b, the outer circumference of the input shaft 310b is used to fix the input wheel 340b, the outer circumference of the intermediate shaft 320b is used to fix the intermediate driving wheel 350b and the intermediate driven wheel 360b, the input wheel 340b is used to mesh with the intermediate driven wheel 360b, and the intermediate driving wheel 350b is used to mesh with the output wheel 330b. The input shaft 310, the intermediate shaft 320, the output wheel 330, the input wheel 340, the intermediate driving wheel 350 and the intermediate driven wheel 360 of the reducer 300a are respectively denoted as the input shaft 310a, the intermediate shaft 320a, the output wheel 330a, the input wheel 340a, the intermediate driving wheel 350a and the intermediate driven wheel 360a. In particular, along the axial direction O of the power assembly 10, the intermediate driving wheels 350b and the intermediate driving wheels 350a of the two reducers 300 are arranged between the input wheel 340b and the input wheel 340a, and the spacing between the input wheel 340b and the input wheel 340a is greater than the spacing between the intermediate driving wheels 350b and the intermediate driving wheels 350a.

[0116] In the embodiment of the present application, along the axial direction O of the power assembly 10, the spacing between the input wheel 340b and the input wheel 340a is recorded as L1, and the spacing between the intermediate driving wheel 350b and the intermediate driving wheel 350a is recorded as L2. Along the axial direction O of the power assembly 10, the intermediate driving wheel 350b and the intermediate driving wheel 350a are arranged between the input wheel 340b and the input wheel 340a, and L1>L2, so that in the dual-motor power assembly 10, the input wheel 340a is arranged on the input shaft 310a close to the rotor 220 of the drive motor 200a, and the input wheel 340b is arranged on the input shaft 310b close to the rotor 220 of the drive motor 200b. 0 arrangement, so that when the drive motor 200 is placed in front or rear, the two input shaft bearings 512a, 621a fixed at both ends of the input shaft 310a and the input shaft 310b are evenly distributed, so that the axial force and radial force on the input shaft 310a and the input shaft 310b will not be concentrated on the same input shaft bearing 512a or input shaft bearing 621a, which can reduce the deformation of the two input shaft bearings 512a, 621a, so that the force transmitted to the housing of the power assembly 10 by the two input shaft bearings 512a, 621a is more uniform, which is conducive to improving the NVH performance of the power assembly 10. It also allows the two arrangements of the drive motor 200 in front or rear to share a set of gear shafts of the reducer 300 under the premise of considering the overall NVH of the power assembly 10, which is conducive to the normalization of the power assembly 10 products.

[0117] Fig.10 is a schematic diagram of an intermediate housing 500 provided in another embodiment of the present application. Fig.11 is another schematic diagram of a powertrain 10 provided in another embodiment of the present application. Fig.12 It is a cross-sectional view of a powertrain 10 provided in another embodiment of the present application.

[0118] In one embodiment, if Fig. 9 and Fig.10 As shown, the housing of the power assembly 10 includes an intermediate housing 500, and the reducer 300a and the reducer 300b are arranged on both sides of the intermediate housing 500 along the axial direction O of the power assembly 10. The intermediate housing 500 includes two side surfaces 510 and an outer peripheral surface 520. The two side surfaces 510 are oriented opposite to each other along the axial direction O of the power assembly 10. The two side surfaces 510 respectively include two reducer receiving grooves 511, and the notches 511a of the two reducer receiving grooves 511 are oriented opposite to each other along the axial direction O of the power assembly 10, as shown in FIG. Fig.10 and Fig.11 As shown, each reducer receiving groove 511 is used to fix and receive a plurality of bearings 380 of a reducer 300. Fig.11 and Fig.12As shown, the outer peripheral surface 520 includes a receiving groove 521, a portion of which is recessed along the radial direction R of the powertrain toward the gap between the input wheel 340b and the input wheel 340a, and the receiving groove 521 is used to accommodate an electrical component 522, which is used to receive the direct current output by the power battery 30 and to deliver direct current to the motor controllers 100 of the drive motor 200a and the drive motor 200b, respectively.

[0119] In the embodiment of the present application, the two side surfaces 510 are oriented opposite to each other along the axial direction O of the power assembly 10, and the two side surfaces 510 respectively include two reducer accommodating grooves 511, and the notches 511a of the two reducer accommodating grooves 511 are opposite to each other along the axial direction O of the power assembly 10, and each reducer accommodating groove 511 is used to fix and accommodate multiple bearings 380 and a gear shaft structure of the reducer 300, so that the two drive motors 200 can independently control the two wheels 40 of the electric vehicle 1 through the two reducers 300.

[0120] In the embodiment of the present application, since the two input wheels 340a and 340b of the two reducers 300 are respectively close to the two driving motors 200a and 200b, there is a large gap between the two input wheels 340a and 340b. In the embodiment of the present application, a part of the receiving groove 521 of the outer peripheral surface 520 is recessed along the radial direction R of the powertrain toward the gap between the input wheel 340b and the input wheel 340a, so that the space between the input wheel 340b and the input wheel 340a along the radial direction R of the powertrain is fully utilized to form the receiving groove 521, and the receiving groove 521 does not occupy too much space outside the shell of the powertrain 10. The space in the receiving groove 521 can be used to accommodate some electrical components, thereby saving space for arranging electrical components outside the shell of the powertrain 10, which is conducive to reducing the overall volume of the powertrain 10, thereby facilitating the optimization of the layout of the powertrain 10 in the vehicle.

[0121] In the embodiment of the present application, the receiving groove 521 is used to receive the electrical component 522, and the electrical component 522 is used to receive the direct current output by the power battery 30 and to transmit the direct current to the motor controllers 100 of the two drive motors 200 respectively, and the direct current is converted into alternating current by the motor controller 100, and the alternating current is transmitted to the two drive motors 200 to drive the two drive motors 200 to operate. Among them, the receiving groove 521 accommodates the electrical component 522 in the motor controller 100, and the electrical component 522 shared by the two motor controllers 100 can be accommodated in the receiving groove 521 of the intermediate housing 500, which makes full use of the gap between the two reducers 300, reduces the layout space of the motor controller 100, and reduces the overall volume of the power assembly 10, which is beneficial to the layout of the power assembly 10 in the whole vehicle.

[0122] In one embodiment, if Fig.12 As shown, a portion of the accommodating groove 521 is recessed along the radial direction R of the powertrain toward the gap between the intermediate driven wheel 360 b and the intermediate driven wheel 360 a .

[0123] In the embodiments of the present application, Fig.11 and Fig.12 As shown, since the two input wheels 340a, 340b of the two reducers 300 are respectively close to the two driving motors 200a, 200b, a large gap is formed between the intermediate driven wheel 360b and the intermediate driven wheel 360a respectively meshed with the input wheels 340a, 340b. A portion of the receiving groove 521 is recessed along the radial direction R of the powertrain toward the gap between the intermediate driven wheel 360b and the intermediate driven wheel 360a, so that the space of the intermediate driven wheels 360b and the intermediate driven wheels 360a of the two reducers 300 along the radial direction R of the powertrain is fully utilized by the receiving groove 521, so that the receiving groove 521 has a larger space for accommodating the electrical component 522, which is more conducive to reducing the volume of the motor controller 100, reducing the overall volume of the powertrain 10, and facilitating the layout of the powertrain 10 in the vehicle.

[0124] Fig.13 It is another cross-sectional view of a powertrain 10 provided in another embodiment of the present application.

[0125] In one embodiment, a portion of the accommodating groove 521 is recessed along the radial direction R of the powertrain toward the gap between the output wheel 330 b and the output wheel 330 a .

[0126] In the embodiment of the present application, a portion of the accommodating groove 521 is recessed along the radial direction R of the powertrain toward the gap between the output wheel 330b and the output wheel 330a, so that the gap between the output wheel 330b and the output wheel 330a of the two reducers 300 can be fully utilized by the accommodating groove 521, which is also beneficial for the accommodating groove 521 to have a larger space to accommodate electrical components, so that more electrical components in the motor controller 100 can be placed in the accommodating groove 521, which is beneficial for reducing the volume of the part of the motor controller 100 arranged outside the intermediate shell 500, reducing the overall volume of the powertrain 10, and facilitating the layout of the powertrain 10 in the entire vehicle.

[0127] In one embodiment, if Fig.10 As shown, the intermediate housing 500 also includes two circumferential plates 523, which are spaced apart along the circumference C of the power assembly 10, and each circumferential plate 523 is fixedly connected to the outer side of the groove wall of the two reducer receiving grooves 511, and the two circumferential plates 523 are used to enclose the outer side of the groove wall of the two reducer receiving grooves 511 to form the receiving groove 521.

[0128] In the embodiment of the present application, two circumferential plates 523 are distributed at intervals along the circumference C of the power assembly 10, and each circumferential plate 523 is fixedly connected to the outer side of the groove wall of the two reducer receiving grooves 511, so that the groove wall of the two reducer receiving grooves 511 can be reused to form the receiving groove 521, and the space of the two reducer receiving grooves 511 along the radial R direction of the power assembly is fully utilized, so that the formation of the receiving groove 521 does not increase the space of the power assembly 10 along the radial R direction of the power assembly, and the receiving groove 521 can accommodate the electrical component 522, reduce the overall volume of the power assembly 10, and thus optimize the layout of the whole vehicle. The two circumferential plates 523 are used to enclose the outer side of the groove wall of the two reducer receiving grooves 511 to form the receiving groove 521, and can also improve the integration and strength of the intermediate housing 500, and improve the overall strength of the housing of the power assembly 10.

[0129] Fig.14 It is a cross-sectional view of an intermediate shell 500 provided in another embodiment of the present application.

[0130] In one embodiment, if Figure 7 and Fig.10 As shown, the bottom of each reducer receiving groove 511 includes an input shaft bearing groove 512 and an output shaft bearing groove 513, the input shaft bearing groove 512 is used to fix the outer ring of an input shaft bearing 512a, the inner ring of the input shaft bearing 512a is used to be fixed to the input shaft 310, the output shaft bearing groove 513 is used to fix the outer ring of an output shaft bearing 513a, the inner ring of the output shaft bearing 513a is used to be fixed to the output shaft 370, and the output shaft 370 is used to fix the output wheel 330. Fig.14 As shown, the spacing between the notches of the output shaft bearing groove 513 at the bottom of the two reducer receiving grooves 511 along the axial direction O of the power assembly 10 is smaller than the spacing between the notches of the input shaft bearing groove 512 at the bottom of the two reducer receiving grooves 511.

[0131] In the embodiment of the present application, the spacing between the notches of the output shaft bearing grooves 513 at the bottom of the two reducer accommodating grooves 511 along the axial direction O of the power assembly 10 is recorded as L3, and the spacing between the notches of the input shaft bearing grooves 512 at the bottom of the two reducer accommodating grooves 511 is recorded as L4, L3<L4, L4 is relatively large, because the input wheel 340a is close to the outside of the drive motor 200a, and the input wheel 340b is close to the outside of the drive motor 200b, so that the input wheels 340a and 340b have more space with the bottom of the reducer accommodating grooves 511 of the intermediate housing 500 to form the input shaft bearing groove 512, which can make the notch of the input shaft bearing groove 512 at the bottom of each reducer accommodating groove 511 closer to the side of the drive motor 200, so that the transmission of the input wheels 340a and 340b is more stable, which is conducive to the normal operation of the power assembly 10. L3 is smaller because the output wheel 330a is close to the inner side of the drive motor 200a, and the output wheel 330b is close to the inner side of the drive motor 200b, so that the grooves of the output shaft bearing groove 513 at the bottom of the two reducer accommodating grooves 511 on the two side surfaces 510 of the intermediate housing 500 are closer, and the intermediate housing 500 has more axial space to accommodate the output wheels 330a and 330b with larger radii.

[0132] Fig.15 is a schematic diagram of an integrated housing 600 provided in another embodiment of the present application. Fig.16 It is a cross-sectional view of an integrated housing 600 provided in another embodiment of the present application.

[0133] In one embodiment, if Fig. 9 and Fig.15 As shown, the housing of the power assembly 10 also includes two integrated housings 600, each of which includes a motor housing 610 and a reducer housing 620. Each motor housing 610 is used to accommodate a stator and a rotor 220 of a drive motor 200a. Each reducer housing 620 is used to enclose a reducer accommodating chamber 630 with the reducer accommodating groove 511 of the intermediate housing 500. Each reducer accommodating chamber 630 is used to accommodate the parallel shaft assembly of the reducer 300. Among them, the axial bottom wall of each reducer housing 620 includes another input shaft bearing groove 621 and another output shaft bearing groove 622. The input shaft bearing groove 621 is used to fix the outer ring of another input shaft bearing 621a, and the inner ring of the input shaft bearing 621a is used to be fixed to the input shaft 310. The output shaft bearing groove 622 is used to fix the outer ring of another output shaft bearing 622a, and the inner ring of the output shaft bearing 622a is used to be fixed to the output shaft 370. The output shaft 370 is used to fix the output wheel 330. As shown in FIG. Fig.16As shown, along the axial direction O of the power assembly 10 , the spacing between the notches of the output shaft bearing groove 622 of the axial bottom wall of the two reducer housings 620 is smaller than the spacing between the notches of the input shaft bearing groove 621 of the axial bottom wall of the two reducer housings 620 .

[0134] In the embodiment of the present application, the spacing between the notches of the output shaft bearing grooves 622 of the axial bottom walls of the two reducer housings 620 along the axial direction O of the powertrain 10 is recorded as L5, and the spacing between the notches of the input shaft bearing grooves 621 of the axial bottom walls of the two reducer housings 620 is recorded as L6, L5<L6, L6 is larger, because the input wheel 340a is close to the outside of the drive motor 200a, and the input wheel 340b is close to the outside of the drive motor 200b, so that the notches of the output shaft bearing grooves 622 of the two integrated housings 600 are relatively far apart along the axial direction O of the powertrain 10, so that the output shaft bearing grooves 622 of the two integrated housings 600 have more axial space to accommodate the input wheel 340a close to the drive motor 200a and the input wheel 340b close to the drive motor 200b. L5 is smaller because the output wheel 330a is arranged away from the drive motor 200a side, and the output wheel 330b is arranged away from the drive motor 200b side, so that the notches of the input shaft bearing grooves 621 of the two integrated housings 600 are closer, thereby reducing the axial length of the output shaft 370a and the output shaft 370b. The output shaft 370a and the output shaft 370b are shorter, making the transmission of the output wheel 330a and the output wheel 330b more stable, which is conducive to the normal operation of the powertrain 10.

[0135] The powertrain and electric vehicle provided in the embodiments of the present application are introduced in detail above. Specific examples are used in this article to illustrate the principles and embodiments of the present application. The description of the above embodiments is only used to help understand the method of the present application and its core idea. At the same time, for those skilled in the art, according to the idea of ​​the present application, there will be changes in the specific embodiments and application scope. In summary, the content of this specification should not be understood as a limitation on the present application.

Claims

1. A powertrain, characterized in that: The power assembly includes a drive motor and a reducer, the reducer includes an input shaft, an intermediate shaft and an output wheel, the input shaft is used for transmission connection with the motor shaft of the drive motor, the outer circumference of the input shaft is used for fixing the input wheel, and the outer circumference of the intermediate shaft is used for fixing the intermediate driving wheel and the intermediate driven wheel, wherein: The input wheel is used to mesh with the intermediate driven wheel, and the intermediate driving wheel is used to mesh with the output wheel. The intermediate driving wheel, the input wheel and the rotor of the driving motor are arranged in sequence along the axial direction of the power assembly.

2. The powertrain according to claim 1, characterized in that: The input wheel is a right-handed gear, and the intermediate driving wheel is a left-handed gear.

3. The powertrain according to claim 1, characterized in that: The helix angle of the input wheel is greater than the helix angle of the intermediate driving wheel.

4. The powertrain according to claim 3, characterized in that: The helix angle of the input wheel is greater than or equal to 27° and less than or equal to 30°, and the helix angle of the intermediate driving wheel is greater than or equal to 17° and less than or equal to 20°.

5. The powertrain according to claim 1, characterized in that: The pressure angle of the intermediate driving wheel is greater than the pressure angle of the input wheel.

6. The powertrain according to claim 5, characterized in that: The pressure angle of the input wheel is greater than or equal to 15.5° and less than or equal to 17.5°, and the pressure angle of the intermediate driving wheel is greater than or equal to 19.5° and less than or equal to 21.5°.

7. The power assembly according to any one of claims 1 to 6, characterized in that: The powertrain further includes a differential, the housing of the differential is used to be fixed to the output wheel, and the half shaft of the differential is used to drive and connect the wheels of the electric vehicle, wherein: The housing of the differential, the output wheel, the input wheel and the rotor of the driving motor are arranged in sequence along the axial direction of the powertrain.

8. The power assembly according to any one of claims 1 to 6, characterized in that: The powertrain further includes two reducers and two drive motors. Along the axial direction of the powertrain, the two reducers are arranged between the two drive motors, wherein: Along the axial direction of the power assembly, the two intermediate driving wheels of the two reducers are arranged between the two input wheels of the two reducers, and the distance between the two input wheels is greater than the distance between the two intermediate driving wheels.

9. The powertrain according to claim 8, characterized in that: The housing of the power assembly includes an intermediate housing, the two reducers are arranged on both sides of the intermediate housing along the axial direction of the power assembly, the intermediate housing includes two side surfaces and an outer peripheral surface, the two side surfaces are oriented opposite to each other along the axial direction of the power assembly, the two side surfaces respectively include two reducer receiving grooves, the notches of the two reducer receiving grooves are opposite to each other along the axial direction of the power assembly, each reducer receiving groove is used to fix and accommodate multiple bearings of a reducer, wherein: The outer peripheral surface includes a receiving groove, a portion of which is recessed along the radial direction of the powertrain toward the gap between the two input wheels of the two reducers, and the receiving groove is used to accommodate an electrical component, which is used to receive direct current output by a power battery and to respectively transmit direct current to the motor controllers of the two drive motors.

10. The powertrain according to claim 9, characterized in that: A portion of the accommodating groove is recessed in a radial direction of the powertrain toward a gap between the two intermediate driven wheels of the two reducers.

11. The powertrain according to claim 9, characterized in that: A portion of the accommodating groove is recessed in a radial direction of the power assembly toward a gap between the two output wheels of the two reducers.

12. The powertrain according to claim 9, characterized in that: The intermediate housing also includes two circumferential plates, which are spaced apart along the circumference of the power assembly, each of which is fixedly connected to the outer side of the groove wall of the two reducer receiving grooves, and the two circumferential plates are used to enclose the outer side of the groove wall of the two reducer receiving grooves to form the receiving groove.

13. The powertrain according to claim 9, characterized in that: The bottom of each reducer receiving groove includes an input shaft bearing groove and an output shaft bearing groove, wherein the input shaft bearing groove is used to fix an outer ring of an input shaft bearing, and the inner ring of the input shaft bearing is used to be fixed to the input shaft, and the output shaft bearing groove is used to fix an outer ring of an output shaft bearing, and the inner ring of the output shaft bearing is used to be fixed to the output shaft, and the output shaft is used to fix the output wheel, wherein: The spacing between the notches of the output shaft bearing groove at the groove bottoms of the two reducer receiving grooves along the axial direction of the power assembly is smaller than the spacing between the notches of the input shaft bearing groove at the groove bottoms of the two reducer receiving grooves.

14. The powertrain according to claim 9, characterized in that: The housing of the power assembly further comprises two integrated housings, each of which comprises a motor housing and a reducer housing, each of which is used to accommodate a stator and a rotor of the drive motor, each of which is used to enclose a reducer accommodating cavity with a reducer accommodating groove of the intermediate housing, and each of which is used to accommodate a parallel shaft assembly of the reducer, wherein: The axial bottom wall of each of the reducer housings comprises another input shaft bearing groove and another output shaft bearing groove, wherein the another input shaft bearing groove is used to fix the outer ring of another input shaft bearing, the inner ring of the another input shaft bearing is used to be fixed to the input shaft, the another output shaft bearing groove is used to fix the outer ring of another output shaft bearing, the inner ring of the another output shaft bearing is used to be fixed to the output shaft, and the output shaft is used to fix the output wheel; The spacing between the notches of the other output shaft bearing groove of the axial bottom walls of the two reducer housings along the axial direction of the power assembly is smaller than the spacing between the notches of the other input shaft bearing groove of the axial bottom walls of the two reducer housings.

15. An electric vehicle, characterized in that: The electric vehicle comprises a frame, a power battery and a power assembly as claimed in any one of claims 1 to 14, wherein the frame is used to fix the power battery and the power assembly.

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