Power assembly and electric vehicle

Abstract

The power assembly comprises a speed reducer and a driving motor, the speed reducer comprises an input shaft, a middle shaft and an output shaft, the input shaft is used for fixing an input wheel, the middle shaft is used for fixing a middle wheel set, the output shaft is used for fixing an output wheel, and a motor shaft of the driving motor is used for being in transmission connection with the input shaft of the speed reducer. The middle wheel set is in transmission connection with the input wheel and the output wheel; the output wheel is used for driving wheels; the included angle formed by the vertical connecting line of the axis of the input shaft and the axis of the middle shaft and the vertical connecting line of the axis of the middle shaft and the axis of the output shaft is larger than or equal to 160 degrees and smaller than or equal to 180 degrees. Under the two conditions that the driving motor is arranged in the front and the driving motor is arranged in the rear, the included angle difference between the two radial forces of the input wheel and the output wheel borne by the middle wheel set is small, the same gear shaft can be used by the same power assembly, the product can be normalized, and the production process is simplified.

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 layout of the powertrain in the vehicle can usually be divided into front-drive motor and rear-drive motor. Considering the NVH performance of the vehicle, the input shaft gear in the reducer adopts a left-handed gear when the drive motor is rear-mounted, and adopts a right-handed gear when the drive motor is front-mounted. This can make the force on the reducer gear shaft more balanced, but two gear structures of the reducer are required to adapt to the front-drive motor state and the rear-drive motor state, which is not conducive to the normalized design of the powertrain. Summary of the invention

[0003] The present application provides a powertrain and an electric vehicle to achieve a normalized design of the powertrain.

[0004] In a first aspect, the present application provides a powertrain, which includes a reducer and a drive motor, wherein the reducer includes an input shaft, an intermediate shaft and an output shaft, wherein the input shaft is used to fix the input wheel, the intermediate shaft is used to fix the intermediate wheel set, the output shaft is used to fix the output wheel, the motor shaft of the drive motor is used to drive and connect the input shaft of the reducer, the intermediate wheel set is used to drive and connect the input wheel and the output wheel, and the output wheel is used to drive the wheel. The angle formed by the vertical line between the axis of the input shaft and the axis of the intermediate shaft and the vertical line between the axis of the intermediate shaft and the axis of the output shaft is greater than or equal to 160° and less than or equal to 180°.

[0005] When the same reducer is used in both the cases where the drive motor is placed in front and the drive motor is placed in the rear, the output torque of the input wheel of the reducer is kept the same, and the radial force exerted by the input wheel on the intermediate wheel set is the same in both the cases where the drive motor is placed in front and the drive motor is placed in the rear. The intermediate wheel group with the drive motor placed at the rear is subjected to radial force from the input wheel and radial force from the output wheel, and the angle between the two radial forces is an acute angle. The intermediate wheel group with the drive motor placed at the front is also subjected to radial force from the input wheel and radial force from the output wheel, and the angle between the two radial forces is an obtuse angle. The angle formed by the perpendicular line connecting the axis center of the input shaft and the axis center of the intermediate shaft and the perpendicular line connecting the axis center of the intermediate shaft and the axis center of the output shaft is set to be greater than or equal to 160° and less than or equal to 180°. This can make the difference between the angle between the two radial forces of the input wheel and the output wheel received by the intermediate wheel group when the drive motor is placed at the rear and the angle between the two radial forces of the input wheel and the output wheel received by the intermediate wheel group when the drive motor is placed at the front smaller, thereby making the difference between the resultant forces of the two radial forces received by the intermediate wheel group smaller, so that in both the case of the drive motor being placed at the front and the drive motor being placed at the rear, the reducer can use the same set of gear shafts, so that the products of the powertrain can be normalized and the production process can be simplified.

[0006] In one embodiment, the angle formed by the vertical line connecting the axis of the input shaft and the axis of the intermediate shaft and the vertical line connecting the axis of the intermediate shaft and the axis of the output shaft is greater than or equal to 165° and less than or equal to 175°. This allows the radial length of the reducer to be smaller while satisfying the condition that the same set of reducers can be used for the front and rear drive motors, which is conducive to the miniaturization of the power assembly.

[0007] In one embodiment, the angle formed by the vertical line connecting the axis of the input shaft and the axis of the intermediate shaft and the vertical line connecting the axis of the intermediate shaft and the axis of the output shaft is equal to 165°. This allows the radial length of the reducer to be smaller and the gear shaft structure of the reducer to be more compact, while satisfying the condition that the same set of reducers can be used for the front and rear drive motors, which is conducive to the miniaturization of the power assembly.

[0008] In one embodiment, the angle formed by the vertical line connecting the axis of the input shaft and the axis of the intermediate shaft and the vertical line connecting the axis of the intermediate shaft and the axis of the output shaft is equal to 170°. This allows the radial length of the reducer to be smaller while satisfying the condition that the same set of reducers can be used for the front and rear drive motors, which is conducive to the miniaturization of the power assembly.

[0009] In one embodiment, the angle formed by the vertical line connecting the axis of the input shaft and the axis of the intermediate shaft and the vertical line connecting the axis of the intermediate shaft and the axis of the output shaft is equal to 175°. This allows the radial length of the reducer to be smaller while satisfying the condition that the same set of reducers can be used for the front and rear drive motors, which is conducive to the miniaturization of the power assembly.

[0010] In one embodiment, an angle formed by a perpendicular line connecting the axis centers of the input shaft and the intermediate shaft and a perpendicular line connecting the axis centers of the intermediate shaft and the output shaft is equal to 180°.

[0011] In one embodiment, along the radial direction of the power assembly, the distance between the axis center of the input shaft and the axis center of the intermediate shaft is less than or equal to the distance between the axis center of the intermediate shaft and the axis center of the output shaft.

[0012] In the embodiment of the present application, along the radial direction of the powertrain, the distance between the axis of the input shaft and the axis of the intermediate shaft is less than or equal to the distance between the axis of the intermediate shaft and the axis of the output shaft, so that the input wheel, the intermediate wheel set and the output wheel can achieve two-stage deceleration, and the difference in the resultant of the two radial forces of the input wheel and the output wheel on the intermediate shaft is relatively small when the drive motor is in the rear state or the drive motor is in the front state.

[0013] In one embodiment, along the radial direction of the powertrain, the distance between the input shaft axis and the intermediate shaft axis is greater than or equal to 80 mm and less than or equal to 100 mm. Along the radial direction of the powertrain, the distance between the intermediate shaft axis and the output shaft axis is greater than or equal to 100 mm and less than or equal to 140 mm.

[0014] In the embodiment of the present application, along the radial direction of the powertrain, the spacing between the axis of the input shaft and the axis of the intermediate shaft is greater than or equal to 80 mm and less than or equal to 100 mm, so that the input wheel and the intermediate wheel set can be transmission-connected when they are close to each other, which is conducive to the input wheel transmitting power to the intermediate wheel set. Along the radial direction of the powertrain, the spacing between the axis of the intermediate shaft and the axis of the output shaft is greater than or equal to 100 mm and less than or equal to 140 mm, so that the intermediate wheel set and the output wheel are transmission-connected when they are far apart, and the output wheel is transmission-connected to the differential, and the layout of the differential requires space. The spacing between the axis of the intermediate shaft and the axis of the output shaft is greater than or equal to 100 mm and less than or equal to 140 mm. The spacing between the axis of the intermediate shaft and the axis of the output shaft is large, which facilitates the layout of the intermediate wheel set and the differential along the radial direction of the powertrain. The spacing between the axis of the input shaft and the axis of the intermediate shaft is greater than or equal to 80 mm and less than or equal to 100 mm, and the spacing between the axis of the intermediate shaft and the axis of the output shaft is greater than or equal to 100 mm and less than or equal to 140 mm, so that the input wheel, the intermediate wheel set and the output wheel can be arranged more compactly and the reducer can have a smaller volume while satisfying that the angle formed by the vertical line connecting the axis of the input shaft and the axis of the intermediate shaft and the vertical line connecting the axis of the intermediate shaft and the axis of the output shaft is greater than or equal to 160° and less than or equal to 180°.

[0015] In one embodiment, along the radial direction of the powertrain, the distance between the input shaft axis and the intermediate shaft axis is greater than or equal to 90 mm and less than or equal to 95 mm. Along the radial direction of the powertrain, the distance between the intermediate shaft axis and the output shaft axis is greater than or equal to 122 mm and less than or equal to 127 mm.

[0016] In one embodiment, along the radial direction of the power assembly, the distance between the axis center of the input shaft and the axis center of the intermediate shaft is equal to 92 mm, and the distance between the axis center of the intermediate shaft and the axis center of the output shaft is equal to 125 mm.

[0017] In one embodiment, the intermediate wheel set includes an intermediate driving wheel and an intermediate driven wheel, wherein the intermediate driven wheel is used for transmission connection with the input wheel, and the intermediate driving wheel is used for transmission connection with the output wheel, wherein the input wheel is a right-handed gear, and the intermediate driving wheel is a left-handed gear.

[0018] In the embodiment of the present application, the intermediate driven wheel is used for transmission connection to the input wheel, and the intermediate driving wheel is used for transmission connection to the output wheel, so that the power transmitted from the motor shaft of the drive motor to the input wheel can be transmitted to the intermediate driven wheel, and the intermediate driven wheel drives the intermediate shaft to rotate, thereby rotating the intermediate driving wheel fixed to the intermediate shaft and transmitting the power to the output wheel. The output wheel is used to drive the wheels through the differential, thereby realizing two-stage reduction of the power of the motor shaft of the drive motor and transmitting it to the differential drive wheel.

[0019] In the embodiment of the present application, the input wheel is a right-handed gear, the intermediate driving wheel is a left-handed gear, and when the drive motor is in the front position, during the operation of the power assembly, the direction of the axial force generated by the input wheel on the intermediate shaft during the transmission between the input wheel and the intermediate driven wheel is toward the drive motor, and the direction of the axial force generated by the intermediate driving wheel on the intermediate shaft during the transmission between the intermediate driving wheel and the output wheel is away from the drive motor. When the drive motor is in the rear position, during the operation of the power assembly, the direction of the axial force generated by the input wheel on the intermediate shaft during the transmission between the input wheel and the intermediate driven wheel is away from the drive motor, and the direction of the axial force generated by the output wheel on the intermediate shaft during the transmission between the intermediate driving wheel and the output wheel is toward the drive motor. In the two states of the drive motor being placed in front or in the rear, the axial force generated on the intermediate shaft during the transmission between the input wheel and the intermediate driven wheel is in opposite direction to the axial force generated on the intermediate shaft during the transmission between the intermediate driving wheel and the output wheel. As a result, the axial force received by the intermediate shaft during the operation of the reducer can be mostly offset, thereby reducing the axial force received by the intermediate shaft, and further reducing the axial force transmitted to the bearing fixed on the intermediate shaft by the intermediate shaft, thereby reducing the force transmitted to the housing of the powertrain by the intermediate shaft bearing, and improving the NVH performance of the powertrain.

[0020] In one embodiment, compared with a powertrain in which the input wheel is a left-handed gear and the intermediate driving wheel is a right-handed gear, the input wheel in the powertrain is a right-handed gear and the intermediate driving wheel is a left-handed gear, so that the overall NVH performance of the powertrain is better when the drive motor is placed in front or in the rear.

[0021] In one embodiment, along the axial direction of the powertrain, the intermediate driven wheel, the intermediate driving wheel, and the rotor of the driving motor are arranged in sequence.

[0022] In the embodiment of the present application, the intermediate driving wheel is connected to the output wheel through a differential, and the output wheel drives the wheel through a differential. Along the axial direction of the powertrain, the intermediate driven wheel, the intermediate driving wheel, and the rotor of the drive motor are arranged in sequence, so that the drive motor has space in the radial direction of the powertrain to place the differential. In one embodiment, the differential is distributed on the side of the output wheel facing the drive motor, so that the differential can be arranged away from the intermediate driven wheel, so that the differential can use the space of the drive motor in the radial direction of the powertrain, without additionally increasing the axial length of the powertrain, which is conducive to the miniaturization of the powertrain.

[0023] In one embodiment, the helix angle of the input wheel is greater than the helix angle of the intermediate driving wheel.

[0024] In the embodiment of the present application, during the operation of the reducer, the input wheel and the output wheel will generate axial forces in opposite directions on the intermediate wheel set, and then generate axial forces in opposite directions on the intermediate shaft used to fix the intermediate wheel set. 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 a 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 a force, so that the difference in the magnitude of the axial forces in opposite directions received by the intermediate driven wheel and the intermediate driving wheel is small. When the intermediate driven wheel and the intermediate driving wheel transmit the axial force to the intermediate shaft, most of the axial forces received by the intermediate shaft can be offset, so that the intermediate shaft and the bearings at both ends can be subjected to a smaller axial force as a whole, so that the force of the powertrain is more balanced, and the NVH performance of the powertrain is improved.

[0025] 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 speed of the intermediate shaft and the intermediate driving wheel is relatively small, and 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 lower speed.

[0026] 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°.

[0027] 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 make the axial force of the input wheel on the intermediate driven wheel and the axial force of the output wheel on the intermediate driving wheel mostly offset, so that the axial force on the intermediate shaft and the bearings at both ends is minimized, so that the force of the powertrain is more balanced, which is beneficial to improving the NVH performance of the powertrain.

[0028] In one embodiment, the helix angle of the input wheel is equal to 28°, and the helix angle of the intermediate driving wheel is equal to 18°.

[0029] 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.

[0030] 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.

[0031] In one embodiment, the pressure angle of the intermediate driving wheel is greater than the pressure angle of the input wheel.

[0032] In the embodiment of the present application, the load of the output wheel in 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. 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 of the input wheel is the smallest, and the pressure angle of the input wheel is set to be smaller to meet the load requirements of the input wheel. In the embodiment of the present application, the pressure angle of the input wheel is smaller, which can make the meshing end surface overlap between the input wheel and the intermediate driven wheel larger, which is conducive to making the input wheel more reliable when rotating at high speed and having better NVH performance.

[0033] In the embodiment of the present application, the pressure angle of the intermediate driving wheel is greater than the pressure angle of the input wheel, so that the combined force of the radial force applied by the input wheel to the intermediate driven wheel and the radial force applied by the output wheel to the intermediate driving wheel can be smaller, thereby allowing the intermediate shaft bearing fixed to the intermediate shaft to bear a smaller radial component force, making the force of the powertrain more balanced.

[0034] 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°.

[0035] In an embodiment of the present application, when the angle formed by a vertical line between the axis center of the input shaft and the axis center of the intermediate shaft and a vertical line between the axis center of the intermediate shaft and the axis center of the output shaft is greater than or equal to 160° and less than or equal to 180°, the pressure angle of the input wheel is set to be 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 set to be greater than or equal to 19.5° and less than or equal to 21.5°. The matching of the pressure angles of the two can minimize the radial component of the intermediate shaft bearing fixed to the intermediate shaft, thereby making the force of the powertrain more balanced, which is beneficial to improving the NVH performance of the powertrain.

[0036] 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°. This also makes the radial force of the input wheel and the output wheel meshing with the intermediate driving wheel on the output shaft bearings at both ends of the intermediate shaft smaller, which is beneficial to improving the NVH performance of the powertrain.

[0037] In one embodiment, the pressure angle of the input wheel is equal to 16°, and the pressure angle of the intermediate driving wheel is equal to 20°.

[0038] 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.

[0039] 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.

[0040] In one embodiment, the housing of the power assembly includes a reducer cavity, the reducer cavity is used to accommodate the input shaft, the intermediate shaft and the output shaft, the cavity wall of the reducer cavity includes two groups of bearing grooves, the two groups of bearing grooves are opposite to each other along the axial direction of the power assembly, each group of bearing grooves includes an input shaft bearing groove, an intermediate shaft bearing groove and an output shaft bearing groove, the input shaft bearing groove, the intermediate shaft bearing groove and the output shaft bearing groove are used to fix the outer ring of the input shaft bearing, the outer ring of the intermediate shaft bearing and the outer ring of the output shaft bearing respectively, and the inner ring of the input shaft bearing, the inner ring of the intermediate shaft bearing and the inner ring of the output shaft bearing are used to be fixed to the input shaft, the intermediate shaft and the output shaft respectively. Wherein, the angle formed by the perpendicular line between the axis center of the input shaft bearing groove and the axis center of the intermediate shaft bearing groove and the perpendicular line between the axis center of the intermediate shaft bearing groove and the axis center of the output shaft bearing groove is greater than or equal to 160° and less than or equal to 180°.

[0041] In the embodiment of the present application, the angle formed by the vertical line connecting the axis of the input shaft bearing groove and the axis of the intermediate shaft bearing groove and the vertical line connecting the axis of the intermediate shaft bearing groove and the axis of the output shaft bearing groove is greater than or equal to 160° and less than or equal to 180°, and the input shaft bearing groove, the intermediate shaft bearing groove and the output shaft bearing groove are respectively used to fix the outer ring of the input shaft bearing, the outer ring of the intermediate shaft bearing and the outer ring of the output shaft bearing, and the inner ring of the input shaft bearing, the inner ring of the intermediate shaft bearing and the inner ring of the output shaft bearing are respectively used to be fixed to the input shaft, the intermediate shaft and the output shaft, so that the axis of the input shaft and The angle formed by the vertical line of the intermediate shaft axis and the vertical line of the intermediate shaft axis and the output shaft axis can also be greater than or equal to 160° and less than or equal to 180°, so that the difference in the angles of the two radial forces of the input wheel and the output wheel received by the intermediate wheel group in the two arrangements of the drive motor being placed in front and the drive motor being placed in the rear is smaller, so that the difference in the resultant force of the two radial forces received by the intermediate wheel group is smaller, so that in the two arrangements of the drive motor being placed in front and the drive motor being placed in the rear, the reducer can use the same set of gear shafts, so that the powertrain products can be normalized and the production process can be simplified.

[0042] In a second aspect, the present application provides an electric vehicle, which includes 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, and the power battery is used to drive a drive motor.

[0043] In the powertrain in the embodiment of the present application, the angle formed by the vertical line connecting the axis of the input shaft and the axis of the intermediate shaft and the vertical line connecting the axis of the intermediate shaft and the axis of the output shaft is greater than or equal to 160° and less than or equal to 180°, so that in the two cases of the drive motor being placed in front and the drive motor being placed in the rear, the radial forces acting on the intermediate wheel group by the input wheel and the output wheel are less different in magnitude, and the angle difference between the radial force provided by the input wheel and the radial force provided by the output wheel on the intermediate wheel group is smaller, so that the difference in the resultant radial forces provided by the input wheel and the output wheel on the intermediate wheel group is smaller, so that in the two arrangements of the drive motor being placed in front and the drive motor being placed in the rear, the same set of reducer gear shaft structure can be used, so that the products of the powertrain can be normalized and the production process can be simplified. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] 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.

[0045] Figure 1 is a schematic diagram of an electric vehicle provided in an embodiment of the present application;

[0046] Figure 2 is a schematic diagram of a powertrain provided in an embodiment of the present application;

[0047] Figure 3It is a schematic diagram of a powertrain drive motor provided in front of an embodiment of the present application;

[0048] Figure 4 It is a schematic diagram of a powertrain drive motor provided in an embodiment of the present application in a rear-mounted manner;

[0049] Figure 5 is a schematic diagram of a reducer provided in an embodiment of the present application;

[0050] Figure 6 This is a force analysis diagram of the intermediate wheel assembly in the rear-mounted driving motor state provided in the embodiment of the present application;

[0051] Figure 7 This is a force analysis diagram of the intermediate wheel set in the front driving motor state provided in the embodiment of the present application;

[0052] Figure 8 This is a force analysis diagram of the intermediate wheel set in the rear-mounted driving motor state provided in the comparative example of the present application;

[0053] Fig. 9 This is a force analysis diagram of the intermediate wheel set in the front-mounted state of the drive motor provided in the comparative example of the present application;

[0054] Fig.10 is a schematic diagram of a housing of a powertrain provided in an embodiment of the present application;

[0055] Fig.11 is a schematic diagram of a right-handed gear provided in an embodiment of the present application;

[0056] Fig.12 is a schematic diagram of a right-handed gear provided in an embodiment of the present application;

[0057] Fig.13 It is a schematic diagram of the helix angle and pressure angle of the gear provided in an embodiment of the present application. DETAILED DESCRIPTION

[0058] 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.

[0059] For ease of understanding, the English abbreviations and related technical terms involved in the embodiments of the present application are explained and described below.

[0060] Front drive motor: refers to the arrangement of the drive motor in front of the reducer in the vehicle's forward direction.

[0061] Rear drive motor: refers to the arrangement of the drive motor behind the differential close to the vehicle's forward direction in the overall vehicle layout.

[0062] NVH: It is the abbreviation of Noise, Vibration and Harshness, which refers to noise, vibration and acoustic roughness.

[0063] The present application provides a power assembly including a reducer and a drive motor, wherein the reducer includes an input shaft, an intermediate shaft and an output shaft, wherein the input shaft is used to fix the input wheel, the intermediate shaft is used to fix the intermediate wheel set, the output shaft is used to fix the output wheel, the motor shaft of the drive motor is used to drive and connect the input shaft of the reducer, the intermediate wheel set is used to drive and connect the input wheel and the output wheel, and the output wheel is used to drive the wheel. Among them, the angle formed by the vertical line connecting the axis of the input shaft and the axis of the intermediate shaft and the vertical line connecting the axis of the intermediate shaft and the axis of the output shaft is greater than or equal to 160° and less than or equal to 180°. In the two cases where the drive motor is placed in front and the drive motor is placed in the rear, the radial force magnitude difference between the input wheel and the output wheel acting on the intermediate wheel set is small, and the radial force angle difference between the input wheel provided by the input wheel and the radial force provided by the output wheel on the intermediate wheel set is small, so that the difference in the combined radial force provided by the input wheel and the output wheel on the intermediate wheel set is small, so that in the two arrangements where the drive motor is placed in front and the drive motor is placed in the rear, the same set of reducer gear shaft structure can be used, so that the products of the power assembly can be normalized and the production process can be simplified.

[0064] 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.

[0065] 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.

[0066] 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, so as 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.

[0067] 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 (not shown). The gear shaft structure of the reducer 300 includes a gear assembly (not shown), an input shaft 310, an intermediate shaft 320 and an output shaft 330. The motor rotor in the drive motor 200 is fixedly sleeved on the motor shaft 210, and the motor stator drives the motor rotor to rotate after receiving alternating current, thereby driving the motor shaft 210 to rotate. The motor shaft 210 of the drive motor 200 is transmission-connected to the input shaft 310 of the reducer 300, and the input shaft 310 receives the power transmitted by the motor shaft 210 of the drive motor 200 and transmits the power to the output shaft 330 through the gear assembly, driving the wheels 40 of the electric vehicle 1 to travel.

[0068] The layout position of the drive motor in the vehicle will affect the layout of the reducer's gear shaft and the movement direction of the gears. Changes in the layout of the reducer's gear shaft and the movement direction of the gears will affect the direction and magnitude of the radial force acting on the intermediate wheel set by the input and output wheels. Therefore, when the powertrain is arranged in the vehicle, the choice of front or rear drive motor placement requires the corresponding adaptation of two different reducer gear shaft structures, which complicates the product design.

[0069] In the embodiment of the present application, by making the angle formed by the vertical line between the axis of the input shaft and the axis of the intermediate shaft and the vertical line between the axis of the intermediate shaft and the axis of the output shaft greater than or equal to 160° and less than or equal to 180°, the radial force on the intermediate wheel assembly as a whole is less different in both the front and rear drive motor situations, so that the powertrain products can be normalized and the production process can be simplified.

[0070] The powertrain 10 provided in an embodiment of the present application will be described in detail below.

[0071] Figure 3 Schematic diagram of a powertrain 10 provided in an embodiment of the present application with a drive motor 200 in front. Figure 4 1 is a schematic diagram of a powertrain 10 provided in an embodiment of the present application in which a drive motor 200 is rear-mounted. Figure 5 is a schematic diagram of a reducer 300 provided in an embodiment of the present application, Figure 6 This is a force analysis diagram of the intermediate wheel set 350 in the rearward state of the drive motor 200 provided in the embodiment of the present application. Figure 7 It is a force analysis diagram of the intermediate wheel assembly 350 in the front state of the drive motor 200 provided in an embodiment of the present application.

[0072] In one embodiment, if Figure 2 As shown, the power assembly 10 includes a reducer 300 and a drive motor 200. Figure 3As shown, the reducer 300 includes an input shaft 310, an intermediate shaft 320 and an output shaft 330. The input shaft 310 is used to fix the input wheel 340, the intermediate shaft 320 is used to fix the intermediate wheel set 350, and the output shaft 330 is used to fix the output wheel 360. The motor shaft 210 of the drive motor 200 is used to drive the input shaft 310 of the reducer 300, the intermediate wheel set 350 is used to drive the input wheel 340 and the output wheel 360, and the output wheel 360 is used to drive the wheel 40. Figure 5 As shown, the angle formed by the perpendicular line between the axis center of the input shaft 310 and the axis center of the intermediate shaft 320 and the perpendicular line between the axis center of the intermediate shaft 320 and the axis center of the output shaft 330 is greater than or equal to 160° and less than or equal to 180°.

[0073] In the embodiment of the present application, the intermediate wheel set 350 is used to drive the input wheel 340 and the output wheel 360. The intermediate driven wheel 352 and the intermediate driving wheel 351 of the intermediate wheel set 350 are respectively driven by the input wheel 340 and the output wheel 360, so that the intermediate wheel set 350 is subjected to both radial forces applied by the input wheel 340 and the output wheel 360. The radial forces applied by the input wheel 340 and the radial forces applied by the output wheel 360 are in different directions and have an angle. At present, the selection of the front drive motor 200 or the rear drive motor 200 according to the layout of the whole vehicle requires the adaptation of two different gear shaft structures of the reducer 300, and the product design is complicated. The arrangement of the gear shaft structure of the reducer 300 will affect the two radial force angles acting on the input wheel 340 and the output wheel 360 on the intermediate wheel group 350 respectively, as well as the magnitude of the resultant force of the two radial forces. If the arrangement of the gear shaft structure of the reducer 300 can be adjusted to make the two radial force angles and the magnitude of the resultant force of the input wheel 340 and the output wheel 360 acting on the intermediate wheel group 350 in both the cases where the drive motor 200 is placed in front and the drive motor 200 is placed in the rear smaller, the same set of gear shaft structure of the reducer 300 can be used for arrangement, which is conducive to achieving product normalization.

[0074] In the embodiments of the present application, Figure 5 As shown, the vertical line between the axis of the input shaft 310 and the axis of the intermediate shaft 320 is marked as L1, the vertical line between the axis of the intermediate shaft 320 and the axis of the output shaft 330 is marked as L2, and the angle formed between L1 and L2 is marked as α1. In the embodiment of the present application, 160°≤α1≤180°.

[0075] like Figure 6 As shown, Figure 6The left side is the forward direction of the electric vehicle. The drive motor 200 is located behind the reducer 300 and is in a rear-mounted state. The rotation direction of the input wheel 340 and the output wheel 360 is counterclockwise. During the process of the input wheel 340 being connected to the intermediate wheel set 350, at the position where the input wheel 340 is tangent to the intermediate driven wheel 352 in the intermediate wheel set 350, the input wheel 340 has a downward radial force F1 on the intermediate driven wheel 352 of the intermediate wheel set 350. During the process of the intermediate driving wheel 351 of the intermediate wheel set 350 being connected to the output wheel 360, the intermediate driving wheel 351 has a radial force on the output wheel 360. The output wheel 360 has a reaction downward radial force F2 on the intermediate driving wheel 351 of the intermediate wheel set 350. The radial force F1 and the radial force F2 on the intermediate wheel set 350 are transmitted to the center position of the intermediate wheel set 350, such as Figure 6 As shown, the radial force of the input wheel 340 on the intermediate driven wheel 352 of the intermediate wheel set 350 is F1', F1'=F1, the radial force of the output wheel 360 on the intermediate driving wheel 351 of the intermediate wheel set 350 is F2', F2'=F2, and the resultant force of F1' and F2' is F12.

[0076] like Figure 7 As shown, Figure 7 The right side is the forward direction of the electric vehicle, the driving motor 200 is located in front of the reducer 300 and is in the front state, the rotation direction of the input wheel 340 and the output wheel 360 is clockwise, and in the process of the input wheel 340 being connected to the intermediate wheel set 350, at the position where the input wheel 340 is tangent to the intermediate driven wheel 352 in the intermediate wheel set 350, the input wheel 340 has a biasing radial force F3 on the intermediate driven wheel 352 of the intermediate wheel set 350, and in the process of the intermediate driving wheel 351 of the intermediate wheel set 350 being connected to the output wheel 360, the intermediate driving wheel 351 has a radial force on the output wheel 360, and the output wheel 360 has a reaction biasing radial force F4 on the intermediate driving wheel 351. When the force applied to the intermediate wheel set 350 is transmitted to the center position of the intermediate wheel set 350, the radial force of the input wheel 340 on the intermediate driven wheel 352 of the intermediate wheel set 350 is F3', F3'=F3, and the radial force of the output wheel 360 on the intermediate driving wheel 35 of the intermediate wheel set 350 is F4', F4'=F4, and the resultant force of F3' and F4' is F34.

[0077] When the same reducer 300 is used in both cases where the drive motor 200 is placed in front and the drive motor 200 is placed in the rear, the output torque of the input wheel 340 of the reducer 300 is kept the same, and the radial force of the input wheel 340 on the intermediate wheel set 350 is the same in both cases where the drive motor 200 is placed in front and the drive motor 200 is placed in the rear. Figure 6It can be seen from the figure that the intermediate wheel set 350 behind the driving motor 200 is subjected to the radial force F1' from the input wheel 340 and the radial force F2' from the output wheel 360. The angle β1 between the two radial forces F1' and F2' is an acute angle. Figure 7 In the case where the driving motor 200 is placed in front, the intermediate wheel assembly 350 is also subjected to the radial force F3' from the input wheel 340 and the radial force F4' from the output wheel 360. The angle β2 between the two radial forces F3' and F4' is an obtuse angle, and is set to 160°≤α1≤180°. This can make the angle β1 between the two radial forces F1' and F2' of the input wheel 340 and the output wheel 360 on the intermediate wheel assembly 350 when the driving motor 200 is placed in the rear and the angle β2 between the two radial forces F3' and F4' of the input wheel 340 and the output wheel 360 on the intermediate wheel assembly 350 when the driving motor 200 is placed in the front smaller, thereby making the difference between the resultant forces F12 and F34 of the two radial forces on the intermediate wheel assembly 350 smaller, so that in both the case of the driving motor 200 being placed in the front and the driving motor 200 being placed in the rear, the reducer 300 can use the same set of gear shafts, so that the products of the powertrain 10 can be normalized and the production process can be simplified.

[0078] Figure 8 This is a force analysis diagram of the intermediate wheel set 350 in the rearward state of the drive motor 200 provided in the comparative example of the present application. Fig. 9 It is a force analysis diagram of the intermediate wheel set 350 in the front state of the drive motor 200 provided in the comparative example of the present application.

[0079] When the angle α1 formed between L1 and L2 is 140°, Figure 8 As shown, in the rearward state of the drive motor 200, the angle between the two radial forces F5' and F6' of the input wheel 340 and the output wheel 360 on the intermediate wheel set 350 is β3, and the resultant force of F5' and F6' is F56. When the angle α1 formed between L1 and L2 is 140°, as shown in FIG. Fig. 9 As shown, in the state where the drive motor 200 is placed in the front position, the angle between the two radial forces F7' and F8' of the input wheel 340 and the output wheel 360 on the intermediate wheel set 350 is β4, and the resultant force of F7' and F8' is F78. Figure 6 and Figure 7In the embodiment of the present application shown, 160°≤α1≤180°, when α1 is 140°, the angle β3 of the two radial forces F5', F6' of the input wheel 340 and the output wheel 360 on the intermediate wheel group 350 in the rearward state of the drive motor 200 and the angle β4 of the two radial forces F7', F8' of the input wheel 340 and the output wheel 360 on the intermediate wheel group 350 in the forward state of the drive motor 200 are quite different, so that the radial force resultant F56, F78 on the intermediate wheel group 350 in the rearward state of the drive motor 200 and in the forward state of the drive motor 200 are quite different. Considering the performance of the powertrain 10, the reducer 300 cannot use the same set of gear shafts, which is not conducive to product normalization of the powertrain 10.

[0080] in, Figure 3 and Figure 5 The input shaft 310 , the intermediate shaft 320 , and the output shaft 330 are only schematic positions and do not represent specific structures.

[0081] In one embodiment, the angle α1 formed by the vertical line L1 between the axis of the input shaft 310 and the axis of the intermediate shaft 320 and the vertical line L2 between the axis of the intermediate shaft 320 and the axis of the output shaft 330 is greater than or equal to 165° and less than or equal to 175°. This allows the radial length of the reducer 300 to be smaller while satisfying the condition that the same set of reducer 300 can be used for both the front and rear drive motors 200, which is beneficial to the miniaturization of the power assembly 10.

[0082] In one embodiment, the angle α1 formed by the vertical line L1 between the axis of the input shaft 310 and the axis of the intermediate shaft 320 and the vertical line L2 between the axis of the intermediate shaft 320 and the axis of the output shaft 330 is equal to 165°. This allows the radial length of the reducer 300 to be smaller while satisfying the condition that the same set of reducer 300 can be used for both the front and rear drive motors 200, making the gear shaft structure of the reducer 300 more compact, which is conducive to the miniaturization of the power assembly 10.

[0083] In one embodiment, the angle α1 formed by the vertical line L1 between the axis of the input shaft 310 and the axis of the intermediate shaft 320 and the vertical line L2 between the axis of the intermediate shaft 320 and the axis of the output shaft 330 is equal to 170°. This allows the radial length of the reducer 300 to be smaller while satisfying the condition that the same set of reducer 300 can be used for both the front and rear drive motors 200, which is conducive to the miniaturization of the power assembly 10.

[0084] In one embodiment, the angle α1 formed by the vertical line L1 between the axis of the input shaft 310 and the axis of the intermediate shaft 320 and the vertical line L2 between the axis of the intermediate shaft 320 and the axis of the output shaft 330 is equal to 175°. This allows the radial length of the reducer 300 to be smaller while satisfying the condition that the same set of reducer 300 can be used for both the front and rear drive motors 200, which is conducive to the miniaturization of the power assembly 10.

[0085] In one embodiment, an angle α1 formed by a perpendicular line L1 between the axis centers of the input shaft 310 and the intermediate shaft 320 and a perpendicular line L2 between the axis centers of the intermediate shaft 320 and the output shaft 330 is equal to 180°.

[0086] Fig.10 It is a schematic diagram of the housing 10a of the power assembly 10 provided in an embodiment of the present application.

[0087] In one embodiment, if Figure 3 and Fig.10 As shown, the housing 10a of the power assembly 10 includes a reducer cavity 500, which is used to accommodate the input shaft 310, the intermediate shaft 320 and the output shaft 330. The cavity wall of the reducer cavity 500 includes two groups of bearing grooves 510. The two groups of bearing grooves 510 are opposite to each other along the axial direction O of the power assembly 10. Each group of bearing grooves 510 includes an input shaft bearing groove 511, an intermediate shaft bearing groove 512 and an output shaft bearing groove 513. The input shaft bearing groove 511, the intermediate shaft bearing groove 512 and the output shaft bearing groove 513 are respectively used to fix the outer ring of the input shaft bearing 511a, the outer ring of the intermediate shaft bearing 512a and the outer ring of the output shaft bearing 513a. The inner ring of the input shaft bearing 511a, the inner ring of the intermediate shaft bearing 512a and the inner ring of the output shaft bearing 513a are respectively used to be fixed to the input shaft 310, the intermediate shaft 320 and the output shaft 330. The angle formed by the vertical line between the axis of the input shaft bearing groove 511 and the axis of the intermediate shaft bearing groove 512 and the vertical line between the axis of the intermediate shaft bearing groove 512 and the axis of the output shaft bearing groove 513 is greater than or equal to 160° and less than or equal to 180°.

[0088] In the embodiment of the present application, the vertical line between the axis center of the input shaft bearing groove 511 and the axis center of the intermediate shaft bearing groove 512 is marked as L3, the vertical line between the axis center of the intermediate shaft bearing groove 512 and the axis center of the output shaft bearing groove 513 is marked as L4, the angle formed between L3 and L4 is marked as α2, 160°≤α2≤180°, and the input shaft bearing groove 511, the intermediate shaft bearing groove 512 and the output shaft bearing groove 513 are respectively used to fix the outer ring of the input shaft bearing 511a, the outer ring of the intermediate shaft bearing 512a and the outer ring of the output shaft bearing 513a, and the inner ring of the input shaft bearing 511a, the inner ring of the intermediate shaft bearing 512a and the inner ring of the output shaft bearing 513a are respectively used to be fixed to the input shaft 310, the intermediate shaft 320 and the output shaft 330, so that Therefore, the angle α1 formed by the vertical line L1 between the axis of the input shaft 310 and the axis of the intermediate shaft 320 and the vertical line L2 between the axis of the intermediate shaft 320 and the axis of the output shaft 330 can also be greater than or equal to 160° and less than or equal to 180°, so that the difference between the two radial force angles β1 and β2 of the input wheel 340 and the output wheel 360 on the intermediate wheel group 350 is small in the two arrangements of the drive motor 200 being placed in front and the drive motor 200 being placed in the rear, so that the difference in the resultant of the two radial forces on the intermediate wheel group 350 is small, so that the reducer 300 can use the same set of gear shafts in the two arrangements of the drive motor 200 being placed in front and the drive motor 200 being placed in the rear, so that the products of the power assembly 10 can be normalized and the production process can be simplified.

[0089] in, Fig.10 The input shaft 310 , the intermediate shaft 320 , and the output shaft 330 are only schematic positions and do not represent specific structures.

[0090] In one embodiment, if Figure 5 As shown, along the radial direction R of the power assembly 10 , the distance between the axis center of the input shaft 310 and the axis center of the intermediate shaft 320 is less than or equal to the distance between the axis center of the intermediate shaft 320 and the axis center of the output shaft 330 .

[0091] In the embodiments of the present application, Figure 3 and Figure 5 As shown, along the radial direction R of the power assembly 10, the distance between the axis center of the input shaft 310 and the axis center of the intermediate shaft 320 is recorded as D1, and the distance between the axis center of the intermediate shaft 320 and the axis center of the output shaft 330 is recorded as D2, and D1≤D2, so that the input wheel 340, the intermediate wheel group 350 and the output wheel 360 can achieve two-stage reduction, and the difference in the resultant forces of the two radial forces of the input wheel 340 and the output wheel 360 on the intermediate shaft 320 is small when the drive motor 200 is in the rear state and the drive motor 200 is in the front state.

[0092] In one embodiment, if Figure 3 and Figure 5As shown, along the radial direction R of the power assembly 10, the distance between the axis of the input shaft 310 and the axis of the intermediate shaft 320 is greater than or equal to 80 mm and less than or equal to 100 mm. Along the radial direction R of the power assembly 10, the distance between the axis of the intermediate shaft 320 and the axis of the output shaft 330 is greater than or equal to 100 mm and less than or equal to 140 mm.

[0093] In the embodiment of the present application, along the radial direction R of the power assembly 10, the distance between the axis of the input shaft 310 and the axis of the intermediate shaft 320 is D1, 80mm≤D1≤100mm, so that the input wheel 340 and the intermediate wheel set 350 can be transmission-connected when they are close to each other, which is beneficial for the input wheel 340 to transmit power to the intermediate wheel set 350. The distance between the axis of the intermediate shaft 320 and the axis of the output shaft 330 is D2, 100mm≤D2≤140mm, so that the intermediate wheel set 350 and the output wheel 360 are transmission-connected when they are far apart, and the output wheel 360 is transmission-connected to the differential 400. The arrangement of the differential 400 requires space, 100mm≤D2≤140mm, and D2 is relatively large, which facilitates the arrangement of the intermediate wheel set 350 and the differential 400 along the radial direction R of the power assembly 10. 80mm≤D1≤100mm, 100mm≤D2≤140mm, so that the input wheel 340, the intermediate wheel set 350 and the output wheel 360 can be arranged more compactly and the reducer 300 can have a smaller volume while satisfying that the angle α1 formed by the vertical line L1 between the axis center of the input shaft 310 and the axis center of the intermediate shaft 320 and the vertical line L2 between the axis center of the intermediate shaft 320 and the axis center of the output shaft 330 is greater than or equal to 160° and less than or equal to 180°.

[0094] In one embodiment, along the radial direction R of the powertrain 10, as shown in FIG. Figure 5 As shown, the distance between the axis of the input shaft 310 and the axis of the intermediate shaft 320 is greater than or equal to 90 mm and less than or equal to 95 mm. Along the radial direction R of the power assembly 10, the distance between the axis of the intermediate shaft 320 and the axis of the output shaft 330 is greater than or equal to 122 mm and less than or equal to 127 mm.

[0095] In one embodiment, along the radial direction R of the power assembly 10 , the distance between the axis center of the input shaft 310 and the axis center of the intermediate shaft 320 is equal to 92 mm, and the distance between the axis center of the intermediate shaft 320 and the axis center of the output shaft 330 is equal to 125 mm.

[0096] Fig.11 is a schematic diagram of a right-handed gear provided in an embodiment of the present application, Fig.12 Schematic diagram of a right-hand gear provided in an embodiment of the present application. Fig.11 As shown in the figure, a right-handed gear is a gear whose helical line S extends to the upper right corner when the helical gear is placed vertically along the axis. Fig.12 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.

[0097] In one embodiment, if Figure 3 As shown, the intermediate wheel set 350 includes an intermediate driving wheel 351 and an intermediate driven wheel 352, wherein the intermediate driven wheel 352 is used for transmission connection with the input wheel 340, and the intermediate driving wheel 351 is used for transmission connection with the output wheel 360. Among them, the input wheel 340 is a right-handed gear, and the intermediate driving wheel 351 is a left-handed gear.

[0098] In the embodiments of the present application, Figure 2 and Figure 3 As shown, the intermediate driven wheel 352 is used for transmission connection to the input wheel 340, and the intermediate driving wheel 351 is used for transmission connection to the output wheel 360, so that the power transmitted from the motor shaft 210 of the drive motor 200 to the input wheel 340 can be transmitted to the intermediate driven wheel 352, and the intermediate driven wheel 352 drives the intermediate shaft 320 to rotate, thereby rotating the intermediate driving wheel 351 fixed to the intermediate shaft 320 and transmitting the power to the output wheel 360, and the output wheel 360 is used to drive the wheel 40 through the differential 400, thereby realizing the two-stage reduction of the power of the motor shaft 210 of the drive motor 200 and transmitting it to the differential 400 to drive the wheel 40.

[0099] In the embodiment of the present application, the input wheel 340 is a right-handed gear, and the intermediate driving wheel 351 is a left-handed gear. Figure 3 As shown, when the drive motor 200 is in the front position, during the operation of the power assembly 10, the axial force generated by the input wheel 340 on the intermediate shaft 320 during the transmission between the input wheel 340 and the intermediate driven wheel 352 is A1, as shown in FIG. Figure 3 As shown, the direction of A1 is toward the driving motor 200, and the axial force generated on the intermediate shaft 320 of the output wheel 360 during the transmission between the intermediate driving wheel 351 and the output wheel 360 is A2. Figure 3 As shown, the direction of A2 is away from the drive motor 200. Figure 4 As shown, in the rear-mounted state of the drive motor 200, during the operation of the power assembly 10, the axial force generated by the input wheel 340 on the intermediate shaft 320 during the transmission process between the input wheel 340 and the intermediate driven wheel 352 is A3, as shown in FIG. Figure 4 As shown, the direction A3 is away from the driving motor 200. During the transmission process between the intermediate driving wheel 351 and the output wheel 360, the axial force generated by the output wheel 360 on the intermediate shaft 320 is A4. Figure 4As shown, the direction of A4 is toward the drive motor 200. When the drive motor 200 is in the front position or the drive motor 200 is in the rear position, the axial force A1 generated on the intermediate shaft 320 during the transmission between the input wheel 340 and the intermediate driven wheel 352 is opposite in direction to the axial force A2 generated on the intermediate shaft 320 during the transmission between the intermediate driving wheel 351 and the output wheel 360, and the axial force A3 generated on the intermediate shaft 320 during the transmission between the input wheel 340 and the intermediate driven wheel 352 is opposite in direction to the axial force A4 generated on the intermediate shaft 320 during the transmission between the intermediate driving wheel 351 and the output wheel 360, so that the axial forces A1 and A2 or A3 and A4 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 320 to the bearing fixed to the intermediate shaft 320, thereby reducing the force transmitted by the intermediate shaft bearing 512a to the housing 10a of the power assembly 10, and improving the NVH performance of the power assembly 10.

[0100] In one embodiment, compared with the input wheel 340 of the powertrain 10 being a left-handed gear and the intermediate driving wheel 351 being a right-handed gear, the input wheel 340 of the powertrain 10 being a right-handed gear and the intermediate driving wheel 351 being a left-handed gear can make the overall NVH performance of the powertrain 10 better when the drive motor 200 is placed in front or the drive motor 200 is placed in the rear.

[0101] in, Figure 3 and Figure 4 The arrow in shows the direction of the axial force generated during the operation of the reducer 300.

[0102] In one embodiment, if Figure 3 As shown, the intermediate driven wheel 352 is meshed and connected with the input wheel 340, and the intermediate driving wheel 351 is meshed and connected with the output wheel 360. Thus, the input wheel 340 can be connected to the intermediate driven wheel 352 in a transmission manner, and the intermediate driving wheel 351 can be connected to the output wheel 360 in a transmission manner.

[0103] In one embodiment, if Figure 3 and Figure 4 As shown, along the axial direction O of the power assembly 10 , the intermediate driven wheel 352 , the intermediate driving wheel 351 , and the rotor of the driving motor 200 are arranged in sequence.

[0104] In the embodiment of the present application, the intermediate driving wheel 351 is connected to the output wheel 360 by transmission, and the output wheel 360 drives the wheel 40 through the differential 400. Along the axial direction O of the power assembly 10, the intermediate driven wheel 352, the intermediate driving wheel 351, and the rotor of the drive motor 200 are arranged in sequence, so that the drive motor 200 has space in the radial direction of the power assembly 10 to place the differential 400. In one embodiment, the differential 400 is distributed on the side of the output wheel 360 facing the drive motor 200, so that the differential 400 can be arranged away from the intermediate driven wheel 352, so that the differential 400 can use the space of the drive motor 200 in the radial direction R of the power assembly 10, without additionally increasing the axial length O of the power assembly 10, which is conducive to the miniaturization of the power assembly 10.

[0105] Fig.13 It is a schematic diagram of the helix angle γ and the pressure angle τ of the gear 600 provided in an embodiment of the present application.

[0106] The helix angle γ 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 method for testing the helix angle γ is as follows: Fig.13 As shown, the outer circumferential surface of the gear 600 includes a plurality of teeth 610. The outer circumferential surface of the gear 600 is flattened to obtain a plane N. The circumferential direction of the gear 600 is flattened to form a first direction B. The normal plane E of each tooth 610 is perpendicular to the extension direction of the tooth 610. The angle between the intersection line L5 of the normal plane E of each tooth 610 and the plane N and the first direction B is the helix angle γ. Another method for testing the helix angle γ is as follows: the angle between the helix line S on the plane N and the axial direction O is the helix angle γ.

[0107] In one embodiment, the helix angle γ of the input wheel 340 is greater than the helix angle γ of the intermediate driving wheel 351 .

[0108] In the embodiments of the present application, Figure 3 , Figure 4 and Fig.13As shown, during the operation of the reducer 300, the input wheel 340 and the output wheel 360 will generate axial forces in opposite directions on the intermediate wheel set 350, and then generate axial forces in opposite directions on the intermediate shaft 320 used to fix the intermediate wheel set 350. In the reducer 300, the torque of the input wheel 340 is small, and the torque of the output wheel 360 is large. The helical angle γ 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 352 larger when the input wheel 340 is connected to the intermediate driven wheel 352 to generate a force, and the helical angle γ of the intermediate driving wheel 351 is small, which is conducive to making the axial component of the output wheel 360 received by the intermediate driving wheel 351 smaller when the intermediate driving wheel 351 is connected to the output wheel 360 to generate a force, so that the difference in the magnitude of the axial forces in opposite directions received by the intermediate driven wheel 352 and the intermediate driving wheel 351 is small. When the intermediate driven wheel 352 and the intermediate driving wheel 351 transmit the axial force to the intermediate shaft 320, most of the axial force on the intermediate shaft 320 can be offset, so that the intermediate shaft 320 and the bearings at both ends can be subjected to a smaller axial force as a whole, making the force on the powertrain 10 more balanced and improving the NVH performance of the powertrain 10.

[0109] In the embodiment of the present application, the helix angle γ of the input wheel 340 is relatively large, which can meet the high-speed transmission requirements of the input wheel 340. After the input wheel 340 transmits power to the intermediate driven wheel 352, the rotation speeds of the intermediate shaft 320 and the intermediate driving wheel 351 are relatively small, and the helix angle γ of the intermediate driving wheel 351 is relatively small, which is also sufficient to meet the low-speed transmission requirements of the intermediate driving wheel 351.

[0110] In one embodiment, the helix angle γ of the input wheel 340 is greater than or equal to 27° and less than or equal to 30°, and the helix angle γ of the intermediate driving wheel 351 is greater than or equal to 17° and less than or equal to 20°.

[0111] In the embodiments of the present application, Figure 3 , Figure 4 and Fig.13 As shown, the helix angle γ 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 γ of the intermediate driving wheel 351 is greater than or equal to 17° and less than or equal to 20°. The matching of the sizes of the helix angles γ of the two can make the axial force of the input wheel 340 on the intermediate driven wheel 352 and the axial force of the output wheel 360 on the intermediate driving wheel 351 mostly offset, so that the axial force on the intermediate shaft 320 and the bearings at both ends is minimized, so that the force on the powertrain 10 is more balanced, which is beneficial to improving the NVH performance of the powertrain 10.

[0112] In one embodiment, the helix angle γ of the input wheel 340 is equal to 28°, and the helix angle γ of the intermediate driving wheel 351 is equal to 18°.

[0113] In one embodiment, the helix angle γ of the intermediate driven wheel 352 is the same as the helix angle γ of the input wheel 340. This allows the intermediate driven wheel 352 to be better meshed with the input wheel 340, so that the tooth surfaces of the intermediate driven wheel 352 and the input wheel 340 have a higher overlap when meshing, which is beneficial to the transmission of power.

[0114] In one embodiment, the helix angle γ of the output wheel 360 is the same as the helix angle γ of the intermediate driving wheel 351. This allows the output wheel 360 to be better meshed with the intermediate driving wheel 351, so that the tooth surfaces of the intermediate driving wheel 351 have a higher overlap when meshing with the output wheel 360, which is beneficial to the transmission of power.

[0115] like Fig.13 As shown, the pressure angle is recorded as τ, which refers to the angle between the tooth profile and the radial line in the gear normal surface. The test method of the pressure angle τ is as follows: Fig.13 As shown, the outer circumferential surface of the gear 600 includes a plurality of teeth 610. The outer circumferential surface of the gear 600 is flattened to obtain a plane N. The normal plane E of each tooth 610 is perpendicular to the extension direction of the tooth 610. The tooth profile of each tooth 610 on the normal plane E is recorded as L6. The radial line of the tooth 610 is recorded as L7. The direction R of the radial line L7 is perpendicular to the plane N. The angle between the tooth profile L6 and the radial line L7 is the pressure angle τ.

[0116] In one embodiment, the pressure angle τ of the intermediate driving wheel 351 is greater than the pressure angle τ of the input wheel 340 .

[0117] In the embodiments of the present application, Figure 3 , Figure 4 and Fig.13 As shown, the load of the output wheel 360 in the reducer 300 is the largest, so that when the intermediate driving wheel 351 is connected to the output wheel 360, the intermediate driving wheel 351 is subjected to a larger radial force component of the output wheel 360. The pressure angle τ of the intermediate driving wheel 351 is set to be larger, so that the load capacity of the intermediate driving wheel 351 is stronger, so that the intermediate driving wheel 351 can withstand the larger radial force component from the output wheel 360 and avoid the teeth of the intermediate driving wheel 351 from being broken. The load of the input wheel 340 is the smallest, and the pressure angle τ of the input wheel 340 is set to be smaller, which can also meet the load requirements of the input wheel 340. In the embodiment of the present application, the pressure angle τ of the input wheel 340 is smaller, which can make the meshing end surface overlap between the input wheel 340 and the intermediate driven wheel 352 larger, which is conducive to making the input wheel 340 more reliable when rotating at high speed and having better NVH performance.

[0118] In the embodiment of the present application, the pressure angle τ of the intermediate driving wheel 351 is greater than the pressure angle τ of the input wheel 340, which can make the combined force of the radial force exerted by the input wheel 340 on the intermediate driven wheel 352 and the radial force exerted by the output wheel 360 on the intermediate driving wheel 351 smaller, thereby making the intermediate shaft bearing 512a fixed to the intermediate shaft 320 bear a smaller radial component force, so that the force on the power assembly 10 is more balanced.

[0119] In one embodiment, the pressure angle τ 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 τ of the intermediate driving wheel 351 is greater than or equal to 19.5° and less than or equal to 21.5°.

[0120] In the embodiments of the present application, Figure 3 , Figure 5 and Fig.13 As shown, when the angle formed by the vertical line L1 between the axis center of the input shaft 310 and the axis center of the intermediate shaft 320 and the vertical line L2 between the axis center of the intermediate shaft 320 and the axis center of the output shaft 330 is greater than or equal to 160° and less than or equal to 180°, the pressure angle τ of the input wheel 340 is set to be greater than or equal to 15.5° and less than or equal to 17.5°, and the pressure angle τ of the intermediate driving wheel 351 is set to be greater than or equal to 19.5° and less than or equal to 21.5°. The matching of the pressure angles τ of the two can minimize the radial component force borne by the intermediate shaft bearing 512a fixed to the intermediate shaft 320, so that the force of the powertrain 10 is more balanced, which is beneficial to improving the NVH performance of the powertrain 10.

[0121] In the embodiment of the present application, the pressure angle τ 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 τ of the intermediate driving wheel 351 is greater than or equal to 19.5° and less than or equal to 21.5°. In addition, the radial force of the input wheel 340 and the output wheel 360 meshing with the intermediate driving wheel 351 on the output shaft bearings 512a at both ends of the intermediate shaft 320 is smaller, which is beneficial to improving the NVH performance of the powertrain 10.

[0122] In one embodiment, the pressure angle τ of the input wheel 340 is equal to 16°, and the pressure angle τ of the intermediate driving wheel 351 is equal to 20°.

[0123] In one embodiment, if Figure 3 and Fig.13 As shown, the pressure angle τ of the intermediate driven wheel 352 is the same as the pressure angle τ of the input wheel 340, so that the tooth surfaces of the intermediate driven wheel 352 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.

[0124] In one embodiment, if Figure 3 and Fig.13 As shown, the pressure angle τ of the output wheel 360 is the same as the pressure angle τ of the intermediate driving wheel 351, so that the tooth surfaces of the intermediate driving wheel 351 have a higher overlap when meshing with the output wheel 360, which is beneficial to making the transmission process smoother and can also improve the NVH performance of the powertrain 10.

[0125] In one embodiment, if Figure 3 As shown, the power assembly 10 further includes a differential 400, which is used for driving connection with the output wheel 360 and the wheel 40. Along the axial direction O of the power assembly 10, the input wheel 340, the output wheel 360, and the differential 400 are arranged in sequence.

[0126] In the embodiment of the present application, along the axial direction O of the powertrain 10, the input wheel 340, the output wheel 360, and the differential 400 are arranged in sequence, so that the arrangement of the differential 400 will not be restricted by the intermediate driven wheel 352, and the differential 400 and the drive motor 200 can be arranged on the same side of the output wheel 360, so that the differential 400 will not occupy additional space outside the axial direction of the drive motor 200 of the powertrain 10, which is conducive to the miniaturization of the powertrain 10 and the optimization of the overall vehicle layout.

[0127] 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 reducer and a drive motor, the reducer includes an input shaft, an intermediate shaft and an output shaft, the input shaft is used to fix the input wheel, the intermediate shaft is used to fix the intermediate wheel set, the output shaft is used to fix the output wheel, the motor shaft of the drive motor is used to drive the input shaft of the reducer, the intermediate wheel set is used to drive the input wheel and the output wheel, and the output wheel is used to drive the wheel, wherein: An angle formed by a perpendicular line connecting the axis center of the input shaft and the axis center of the intermediate shaft and a perpendicular line connecting the axis center of the intermediate shaft and the axis center of the output shaft is greater than or equal to 160° and less than or equal to 180°.

2. The powertrain according to claim 1, characterized in that: Along the radial direction of the power assembly, the distance between the axis center of the input shaft and the axis center of the intermediate shaft is less than or equal to the distance between the axis center of the intermediate shaft and the axis center of the output shaft.

3. The powertrain according to claim 2, characterized in that: Along the radial direction of the power assembly, the distance between the axis center of the input shaft and the axis center of the intermediate shaft is greater than or equal to 80 mm and less than or equal to 100 mm; Along the radial direction of the power assembly, the distance between the axis center of the intermediate shaft and the axis center of the output shaft is greater than or equal to 100 mm and less than or equal to 140 mm.

4. The powertrain according to any one of claims 1 to 3, characterized in that: The intermediate wheel set includes an intermediate driving wheel and an intermediate driven wheel, wherein the intermediate driven wheel is used for transmission connection with the input wheel, and the intermediate driving wheel is used for transmission connection with the output wheel, wherein: The input wheel is a right-handed gear, and the intermediate driving wheel is a left-handed gear.

5. The powertrain according to claim 4, characterized in that: Along the axial direction of the power assembly, the intermediate driven wheel, the intermediate driving wheel, and the rotor of the driving motor are arranged in sequence.

6. The powertrain according to any one of claims 1 to 5, characterized in that: The helix angle of the input wheel is greater than the helix angle of the intermediate driving wheel.

7. The power assembly according to claim 6, wherein 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°.

8. The power assembly according to any one of claims 1 to 7, wherein a pressure angle of the intermediate driving wheel is greater than a pressure angle of the input wheel.

9. The powertrain according to claim 8, wherein 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°.

10. The power assembly according to any one of claims 1 to 9, characterized in that: The housing of the power assembly includes a reducer cavity, which is used to accommodate the input shaft, the intermediate shaft and the output shaft. The cavity wall of the reducer cavity includes two groups of bearing grooves, which are opposite to each other along the axial direction of the power assembly. Each group of bearing grooves includes an input shaft bearing groove, an intermediate shaft bearing groove and an output shaft bearing groove. The input shaft bearing groove, the intermediate shaft bearing groove and the output shaft bearing groove are respectively used to fix the outer ring of the input shaft bearing, the outer ring of the intermediate shaft bearing and the outer ring of the output shaft bearing. The inner ring of the input shaft bearing, the inner ring of the intermediate shaft bearing and the inner ring of the output shaft bearing are respectively used to be fixed to the input shaft, the intermediate shaft and the output shaft, wherein: An angle formed by a perpendicular line between the axis of the input shaft bearing groove and the axis of the intermediate shaft bearing groove and a perpendicular line between the axis of the intermediate shaft bearing groove and the axis of the output shaft bearing groove is greater than or equal to 160° and less than or equal to 180°.

11. An electric vehicle, characterized in that: The electric vehicle comprises a frame, a power battery and a power assembly as described in any one of claims 1 to 10, wherein the frame is used to fix the power battery and the power assembly, and the power battery is used to drive the drive motor.

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