Powertrain and electric vehicle

Abstract

The present application provides a powertrain and an electric vehicle. A housing of the powertrain is used for fixing a stator of a drive motor and accommodating a rotor of the drive motor. The rotor of the drive motor is fixed to a motor shaft of the drive motor. The motor shaft of the drive motor is configured to be transmittingly connected to an input shaft of a speed reducer. The motor shaft comprises a cooling flow channel and a lubrication flow channel. The cooling flow channel is used for delivering one stream of oil to the rotor of the drive motor for cooling, thereby ensuring that even when the motor shaft rotates at a high speed, the oil flowing in the motor shaft can cool the rotor of the drive motor by means of the cooling flow channel, so that the temperature of the drive motor does not cause a fault due to overheating. The lubrication flow channel is used for delivering another stream of oil to the speed reducer for lubrication, so that when the motor shaft rotates, the oil lubricates the speed reducer by means of the lubrication flow channel, helping ensure normal operation of the speed reducer.

Description

Powertrain and electric vehicles

[0001] This application claims priority to Chinese Patent Application No. 202423319959.X, filed with the Chinese Patent Office on December 31, 2024, entitled "Powertrain and Electric Vehicle", the entire contents of which are incorporated herein by reference. Technical Field

[0002] This application relates to the field of electric vehicle technology, and in particular to a powertrain and an electric vehicle. Background Technology

[0003] To meet the power demands of new energy vehicles, the power density requirements for drive motors are increasing. The higher the power of the drive motor, the greater the requirements for its heat dissipation capacity. Both the gear shaft assembly of the reducer and the motor rotor in the powertrain require oil for cooling and lubrication. Generally, lubricating oil is introduced from the end of the motor shaft into the inner bore of the motor shaft through oil passages and guide pipes in the housing, and then reaches the motor rotor through the oil spray holes on the motor shaft to cool it. However, when the motor shaft rotates at high speed, the oil inside the shaft is often thrown out of the oil holes halfway through, failing to flow to the other end of the motor shaft to cool the entire shaft, and also failing to transfer the oil inside the motor shaft to the gear shaft assembly of the reducer for lubrication. Summary of the Invention

[0004] This application provides a powertrain and electric vehicle, which allows the oil in the motor shaft to lubricate the reducer even when the drive motor is rotating at high speed.

[0005] In a first aspect, this application provides a powertrain, wherein the housing of the powertrain is used to fix the stator of a drive motor and to house the rotor of the drive motor, the rotor of the drive motor is fixed to the motor shaft of the drive motor, and the motor shaft of the drive motor is used to drively connect to the input shaft of a reducer. The motor shaft includes a cooling channel and a lubrication channel, the cooling channel being used to deliver one path of oil to the rotor of the drive motor for cooling, and the lubrication channel being used to deliver another path of oil to the reducer for lubrication.

[0006] In this embodiment, the motor shaft of the drive motor rotates at high speed during operation, generating a large amount of heat. Oil needs to be introduced into the motor shaft for cooling. Both cooling and lubrication channels are provided within the motor shaft. The cooling channel delivers one stream of oil to the rotor of the drive motor for cooling, while the lubrication channel delivers another stream of oil to the reducer for lubrication. This allows the oil entering the motor shaft to be split: one stream cools the rotor of the drive motor, preventing overheating and malfunction, while the other stream lubricates the gears of the reducer, reducing the rotational resistance between the gear shaft assembly and improving the reducer's efficiency. The cooling and lubrication channels also allow the oil to flow across the entire motor shaft, ensuring thorough cooling and lubrication of the entire shaft.

[0007] If the oil is only supplied to the rotor of the drive motor by throwing oil through the oil hole on the motor shaft during rotation, as the rotor speed of the drive motor increases, almost all the oil will be thrown out after passing through the oil hole to cool the rotor of the drive motor. This prevents the oil from flowing through the entire motor shaft, which in turn prevents the reducer from receiving the oil supplied from the motor shaft. This increases the heat generated by the reducer, reduces the load-bearing capacity of the reducer, shortens its service life, and is detrimental to the normal operation of the reducer.

[0008] In this embodiment, by providing a lubrication channel and a cooling channel within the motor shaft, the channel for cooling the rotor of the drive motor and the channel for lubricating the reducer are two separate channels. This ensures that even when the motor shaft rotates at high speed, the other path of oil flowing within the motor shaft can lubricate the reducer through the lubrication channel, which is beneficial for ensuring the normal operation of the reducer.

[0009] In one embodiment, the flow rate of the additional oil path used for delivery through the lubrication channel is greater than the flow rate of the additional oil path used for delivery through the cooling channel of the motor shaft. And / or the path of the additional oil path through the lubrication channel is greater than the path of the additional oil path through the cooling channel.

[0010] In this embodiment, the flow rate of the other oil path used for lubrication is greater than the flow rate of the oil path used for cooling the motor shaft. This allows more oil within the motor shaft to be used for lubricating the reducer, meeting the reducer's lubrication requirements at low temperatures and ensuring its normal operation. The smaller flow rate of the oil path in the cooling channel is also sufficient to meet the cooling requirements of the motor rotor at low temperatures.

[0011] In one embodiment, the path of another oil flow through the lubrication channel is greater than the path of one oil flow through the cooling channel.

[0012] Because the drive motor generates significant heat during operation, timely cooling is necessary to prevent overheating. In this embodiment, the path of one oil path through the cooling channel is shorter, allowing the cooling channel to be shorter than the lubrication channel. This brings the cooling channel closer to the drive motor rotor, facilitating more thorough cooling of the rotor. Conversely, a longer path for one oil path to the cooling channel would delay the rotor's arrival, hindering timely cooling. Therefore, this application extends the lubrication channel's path beyond that of the cooling channel. This provides an independent lubrication channel for the reducer while simultaneously cooling the drive motor, improving drive motor efficiency and reducer performance, ultimately enhancing the overall powertrain performance.

[0013] In one embodiment, the flow rate of the additional oil supplied by the lubrication channel is greater than the flow rate of the oil supplied by the cooling channel of the motor shaft, and the path of the additional oil flowing through the lubrication channel is greater than the path of the oil flowing through the cooling channel. This improves the efficiency of the drive motor and the performance of the reducer even at low ambient temperatures, thereby enhancing the overall performance of the powertrain.

[0014] In one embodiment, the inlet and outlet openings of the lubrication channel are oriented opposite to each other along the axial direction of the powertrain, the inlet opening of the cooling channel is oriented in the same direction as the inlet opening of the lubrication channel, and the outlet opening of the cooling channel is oriented parallel to the radial direction of the powertrain.

[0015] In this embodiment, the inlet and outlet openings of the lubrication channel face opposite directions along the axial direction of the powertrain. This allows the other path of oil from the lubrication channel within the motor shaft to be delivered directly to the reducer along the axial direction of the powertrain more quickly and via a shorter path, thus lubricating the reducer and ensuring its normal operation. It also facilitates the machining of the lubrication channel within the motor shaft.

[0016] In this embodiment, the opening orientation of the cooling channel inlet is the same as that of the lubrication channel inlet. This allows both the cooling and lubrication channels to simultaneously receive oil flowing into the motor shaft, ensuring oil flow separation within the motor shaft and guaranteeing oil flow through both the cooling and lubrication channels. This allows for cooling of the motor rotor while simultaneously providing adequate lubrication to the gear shaft assembly of the reducer. Compared to designs where the cooling and lubrication channel inlets have different opening orientations, having the same orientation simplifies the channel design. This allows both channels to receive oil from the same side, resulting in a more focused and simplified oil delivery structure.

[0017] In this embodiment, one path of oil in the cooling channel is used to cool the rotor of the drive motor. The opening of the outlet of the cooling channel is parallel to the radial direction of the powertrain, and the opening of the outlet of the cooling channel is aligned with the direction of the centrifugal force of the motor shaft rotation. This makes it easier to throw the oil in the cooling channel out to the rotor of the drive motor through the high-speed rotation of the motor shaft, thereby cooling the rotor of the drive motor.

[0018] In one embodiment, the inlet of the cooling channel surrounds the outer periphery of the inlet of the lubrication channel, and the inlets of the cooling channel and the lubrication channel are radially spaced apart along the powertrain.

[0019] In this embodiment, the inlet of the cooling channel surrounds the outer periphery of the inlet of the lubrication channel, thereby allowing the lubrication channel to be arranged near the motor shaft axis and the cooling channel to be arranged near the outer periphery of the motor shaft. This makes it easier for the oil in the cooling channel to be thrown out of the cooling channel by the rotation of the motor shaft to cool the rotor of the drive motor.

[0020] In this embodiment, the inlet of the cooling channel and the inlet of the lubrication channel are radially spaced along the powertrain, so that one path of oil in the cooling channel and another path of oil in the lubrication channel can flow relatively independently, thereby ensuring that one path of oil in the motor shaft is used to lubricate the reducer and the other path of oil is used to cool the rotor of the drive motor.

[0021] In one embodiment, the cooling channels and lubrication channels can be integrally machined in the motor shaft, resulting in higher structural strength of the motor shaft.

[0022] In one embodiment, the orifice diameter of the inlet of the radial lubrication channel along the powertrain is larger than the width of the inlet of the cooling channel.

[0023] In this embodiment, the inlet diameter of the radial lubrication channel of the powertrain is larger than the inlet width of the cooling channel, so that the amount of oil flowing into the lubrication channel is larger than the amount of oil flowing into the cooling channel. This ensures that there is enough oil to be delivered to the reducer for lubrication when the environment is low, which is beneficial to ensuring the normal operation of the reducer.

[0024] In this embodiment, the cooling channel is arranged around the lubrication channel, and the width of the inlet of the cooling channel is set to be small, which helps to keep the motor shaft with a thicker wall, thereby making the motor shaft more reliable.

[0025] In one embodiment, the inlet of the cooling channel surrounds the outer periphery of the inlet of the lubrication channel, and the aperture of the inlet of the lubrication channel along the radial direction of the powertrain is larger than the width of the inlet of the cooling channel. In this embodiment, when the inlet of the cooling channel is arranged around the outer periphery of the inlet of the lubrication channel, the cooling channel is annular. This allows the flow area of ​​the cooling channel inlet to be larger than the flow area of ​​the lubrication channel inlet, even when the width of the cooling channel inlet is smaller than the aperture of the lubrication channel inlet. This ensures that the lubrication requirements of the reducer can be met while simultaneously cooling the drive motor.

[0026] In one embodiment, the distance between the inlet and outlet of the cooling channel is smaller than the distance between the inlet and outlet of the lubrication channel along the axial direction of the powertrain.

[0027] In this embodiment, along the axial direction of the powertrain, the distance between the inlet and outlet of the cooling channel is smaller than that of the lubrication channel. This results in a shorter length of the cooling channel compared to the lubrication channel, allowing the oil to flow closer to the drive motor rotor. This ensures that the oil ejected from the cooling channel outlet can better cover the drive motor rotor, improving the cooling efficiency of one oil path. The larger distance between the inlet and outlet of the lubrication channel results in a longer lubrication channel, facilitating the delivery of another oil path via the motor shaft to a more distant reducer for lubrication, ensuring the reducer's normal operation.

[0028] In one embodiment, the motor shaft further includes a radial flow channel, the inlet of which is connected to a cooling flow channel, and the outlet of which is parallel to the radial direction of the powertrain. The radial flow channel is used to transmit one path of oil output from the cooling flow channel to the rotor of the drive motor.

[0029] In this embodiment of the application, the motor shaft further includes a radial flow channel. The inlet of the radial flow channel is used to connect to the cooling flow channel, so that one path of oil in the cooling flow channel can flow out through the radial flow channel to the rotor of the drive motor.

[0030] In this embodiment, the outlet of the radial flow channel is parallel to the radial direction of the powertrain, which allows the radial flow channel to be shorter. This makes it easier for the motor shaft to quickly pass through the radial flow channel during high-speed rotation and throw the oil in the cooling channel to the rotor of the drive motor, thereby improving the cooling efficiency of the drive motor rotor.

[0031] In one embodiment, the motor shaft includes two radial flow channels, with different spacing between the inlets of the two radial flow channels and the cooling flow channels along the axial direction of the powertrain.

[0032] In this embodiment, the motor shaft includes two radial flow channels. The distance between the two radial flow channels and the inlet of the cooling flow channel along the axial direction of the powertrain is different. This allows one path of oil in the cooling flow channel to be thrown out at different positions on the motor shaft, which is more conducive to the contact area between the thrown-out oil and the rotor of the drive motor, thus improving the cooling efficiency.

[0033] In this embodiment, when the rotational speed of the motor shaft of the drive motor is low, the centrifugal force on one of the oil channels in the cooling channel is small, which makes it easy for the oil in the cooling channel to flow back to the inlet of the cooling channel. Setting a radial channel close to the inlet of the cooling channel is beneficial to make the oil flow through the radial channel and then flow out to the rotor of the drive motor, so as to ensure that the rotor of the drive motor has enough oil for cooling.

[0034] In one embodiment, the motor shaft includes a rotating shaft and an oil passage. The rotating shaft includes a shaft cavity that extends through the motor shaft along the axial direction of the powertrain. The shaft cavity is used to accommodate and fix the oil passage. The oil passage includes a through hole that extends through the oil passage along the axial direction of the powertrain. The through hole is used to form a lubrication channel.

[0035] In this embodiment, the motor shaft includes a rotating shaft and an oil passage. The rotating shaft includes a shaft cavity that extends through the motor shaft along the axial direction of the powertrain, allowing the oil passage to be arranged within the shaft cavity of the rotating shaft. Dividing the motor shaft into a rotating shaft and an oil passage also facilitates the machining of the lubrication channel and simplifies the machining process.

[0036] In this embodiment, the through hole of the oil pipe extends through the oil pipe along the axial direction of the powertrain, which facilitates the direct machining of the through hole in the oil pipe to form a lubrication channel. It also allows the lubrication channel to be parallel to the axial direction of the powertrain, thereby enabling the other path of oil in the lubrication channel to be transmitted to the reducer located on the drive motor side at a faster speed and shorter distance, for lubrication of the gear shaft assembly of the reducer, which is beneficial to ensuring the normal operation of the reducer.

[0037] In one embodiment, the oil passage further includes an annular groove, which is recessed from one end face of the oil passage toward the other end of the oil passage along the axial direction of the powertrain. The annular groove surrounds the through hole and is used to form a cooling channel. The groove opening of the annular groove is the inlet of the cooling channel. The groove wall of the annular groove includes a connecting hole, which penetrates the groove wall of the annular groove along the radial direction of the powertrain. The connecting hole is the outlet of the cooling channel.

[0038] In this embodiment of the application, the oil passage pipe also includes an annular groove, which is a recess along the axial direction of the powertrain from one end face of the oil passage pipe toward the other end of the oil passage pipe, thereby facilitating the machining of the annular groove from one end of the oil passage pipe, or facilitating demolding from the other end of the oil passage pipe to form the annular groove.

[0039] In this embodiment, an annular groove surrounds the through hole and forms a cooling channel. This allows the cooling channel to be arranged around the lubrication channel of the through hole, and also allows the cooling channel in the annular groove and the lubrication channel in the through hole to transport oil relatively independently. This ensures that one path of oil entering the oil pipe can be used to cool the rotor of the drive motor, preventing the drive motor from overheating and malfunctioning, while the other path of oil can be used to lubricate the reducer, which helps ensure the normal operation of the reducer.

[0040] In this embodiment, the opening of the annular groove is the inlet of the cooling channel, allowing a stream of oil to flow into the cooling channel through the opening of the annular groove. The groove wall of the annular groove includes a connecting hole, which penetrates the groove wall along the radial connecting hole of the powertrain. The connecting hole is the outlet of the cooling channel, allowing a stream of oil in the cooling channel to be discharged from the annular groove through the connecting hole on the groove wall of the annular groove for cooling the rotor of the drive motor.

[0041] In this embodiment, the connecting hole penetrates the wall of the annular groove radially along the powertrain. This facilitates direct machining of the connecting hole from the oil pipe along the radial direction of the powertrain, and also allows the connecting hole to have a shorter length, enabling faster oil ejection when the motor shaft rotates at high speed. Furthermore, it allows the oil to be sprayed radially along the powertrain, resulting in more oil being sprayed onto the rotor of the drive motor, thus improving cooling efficiency.

[0042] In one embodiment, the cooling channel can be formed by the outer wall of the oil pipe and the inner wall of the rotating shaft, simplifying the formation process of the cooling channel.

[0043] In one embodiment, the cooling channels and lubrication channels are integrally formed in the motor shaft. In another embodiment, the motor shaft is an integral structure.

[0044] In one embodiment, the powertrain housing includes a bearing groove for securing the outer ring of a bearing and the inner ring of the bearing for securing it to a motor shaft. The opening of the bearing groove faces the rotor of the drive motor along the axial direction of the powertrain. The bottom of the bearing groove includes an oil outlet, the opening of which faces the rotor of the drive motor along the axial direction of the powertrain. The oil outlet is used to discharge oil into at least one of a cooling channel and a lubrication channel.

[0045] In this embodiment, the opening of the bearing groove faces the rotor of the drive motor along the axial direction of the powertrain, which makes it easier to fix the bearing in the bearing groove to the motor shaft.

[0046] In this embodiment of the application, the bottom of the bearing groove includes an oil outlet hole. The opening of the oil outlet hole faces the rotor of the drive motor along the axial direction of the powertrain. This allows the oil output from the oil outlet hole to flow directly towards the rotor of the drive motor, making the oil output from the oil outlet hole flow more smoothly to the rotor of the drive motor. It also helps to bring the oil outlet hole closer to the rotor of the drive motor, allowing the rotor of the drive motor to be cooled down by the oil more quickly, which is beneficial to improving the cooling efficiency of the drive motor.

[0047] In this embodiment, the oil outlet is used to output oil to at least one of the cooling channel and the lubrication channel, so that the oil output from the oil outlet can enter the motor shaft and be split within the motor shaft. One path of oil flowing to the cooling channel can be used to cool the rotor of the drive motor, while the other path of oil flowing to the lubrication channel can be used to lubricate the gear shaft assembly of the reducer, which helps to ensure the normal operation of the reducer.

[0048] In one embodiment, oil is supplied to both the cooling and lubrication channels through a single oil outlet, simplifying the oil supply structure. In another embodiment, the bottom of the bearing groove includes two oil outlets, which supply oil to the cooling and lubrication channels respectively. This allows for more precise control of the flow rates in the cooling and lubrication channels, resulting in better cooling of the drive motor rotor and improved lubrication of the reducer, thereby enhancing the efficiency of the powertrain cooling and lubrication system.

[0049] In one embodiment, the inlet of the cooling channel or lubrication channel is embedded in the oil outlet hole. In another embodiment, the oil outlet hole is embedded in the inlet of the cooling channel or lubrication channel.

[0050] In one embodiment, an oil outlet along the axial direction of the powertrain is spaced from the inlet of at least one of a cooling channel and a lubrication channel. The oil outlet is used to fix a nozzle, which is used to deliver oil output from the oil outlet to the cooling channel or the lubrication channel.

[0051] In the embodiments of this application, the oil outlet along the axial direction of the powertrain is spaced apart from the inlet of at least one of the cooling channel and the lubrication channel, thereby creating space between the oil outlet and the cooling channel and the lubrication channel for arranging the nozzle.

[0052] In this embodiment, the oil outlet is used to fix the nozzle, and the nozzle is used to deliver the oil output from the oil outlet to the cooling channel or the lubrication channel. By setting the nozzle in the oil outlet, the oil flowing out of the oil outlet can be split by the nozzle and flow to the cooling channel or the lubrication channel respectively, so that there is oil in the motor shaft, thereby facilitating the cooling of the rotor of the drive motor or the lubrication of the reducer.

[0053] In one embodiment, the nozzle includes two outlets that respectively supply oil to a cooling channel and a lubrication channel.

[0054] In one embodiment, the housing is used to enclose the reducer housing to form a motor cavity, the motor cavity is used to accommodate the stator and rotor of the drive motor, the reducer housing is used to accommodate the gear shaft assembly of the reducer, the reducer housing includes a through hole that extends through the reducer housing along the axial direction of the motor shaft, the through hole is used to pass through one end of the motor shaft, the end of the motor shaft passing through the through hole extends into the reducer housing, the outlet of the lubrication flow channel is distributed at one end of the motor shaft, and one end of the motor shaft is used to drive at least one gear of the reducer.

[0055] In the embodiments of this application, the housing is used to enclose the reducer housing to form the motor cavity, so that the formation of the motor cavity can be achieved by using the reducer housing, which is beneficial to making the housing of the powertrain more integrated.

[0056] In this embodiment, the reducer housing includes a through hole that extends axially through the motor shaft, thereby creating conditions for one end of the motor shaft to pass through the through hole and extend into the reducer housing. Having one end of the motor shaft extend into the reducer housing facilitates the lubrication channels within the motor shaft in delivering another path of oil to the gear shaft assembly of the reducer for lubrication.

[0057] In this embodiment, the outlet of the lubrication channel is located at one end of the motor shaft, which extends into the reducer housing. This allows the other path of oil in the lubrication channel to be directly sprayed into the reducer housing. The other end of the motor shaft is used to drive at least one gear of the reducer, making the outlet of the lubrication channel closer to at least one gear of the reducer. This facilitates spraying the other path of oil from the lubrication channel onto the gear shaft assembly of the reducer, and more precisely delivers the other path of oil to the gear shaft assembly for lubrication.

[0058] In one embodiment, the reducer includes a sun gear, a planet carrier, and a plurality of planet gears. One end of the motor shaft is used to drive the sun gear. The plurality of planet gears are distributed around the outer periphery of the sun gear along the circumference of the motor shaft. The outlet of the lubrication channel along the axial direction of the powertrain is exposed to the sun gear. Another path of oil output from the outlet of the lubrication channel is used to cool the plurality of planet gears.

[0059] In this embodiment, one end of the motor shaft is used to drive the sun gear, and multiple planetary gears are distributed around the outer periphery of the sun gear along the circumference of the motor shaft, so that the power of the drive motor can be transmitted to the sun gear of the reducer through the motor shaft, driving the sun gear of the reducer to rotate. The sun gear then transmits the power to the multiple planetary gears, causing the multiple planetary gears to move, thereby driving the output half shaft to drive the wheel.

[0060] In this embodiment, the outlet of the axial lubrication channel of the powertrain is exposed to the sun gear, so that when the motor shaft rotates at high speed, the oil flowing out from the outlet of the lubrication channel will not hit the shaft cavity of the motor shaft, but can be directly thrown out of the motor shaft. This makes it easier for the other oil in the lubrication channel to lubricate the sun gear and the multiple planetary gears located around the sun gear in the radial direction of the powertrain when the motor shaft rotates.

[0061] In this embodiment, the other oil output from the lubrication channel is used to cool multiple planetary gears, which helps ensure the normal operation of the multiple planetary gears.

[0062] In one embodiment, when the length of the outlet of the lubrication channel is insufficient to be exposed to the sun gear, a nozzle can be connected to the outlet of the lubrication channel to ensure that the other oil output from the outlet of the lubrication channel can be directly sprayed onto the gear shaft assembly of the reducer to fully lubricate the gear shaft assembly of the reducer.

[0063] In one embodiment, when the reducer includes two stages of planetary gears, the outlet of the lubrication channel along the axial direction of the powertrain is distributed between the two stages of planetary gears, and the lubrication channel lubricates the two stages of planetary gears.

[0064] In one embodiment, the powertrain includes two drive motors and two reducers. The two drive motors are arranged between the two reducers. The powertrain includes two reducer housings, each housing having a partition that divides the housing into two motor slots. The openings of the two motor slots face away from each other along the axial direction of the powertrain. Each motor slot encloses a reducer housing to form a motor cavity. The partition includes two bearing slots, with their openings facing away from each other along the axial direction of the powertrain. The bottom of each bearing slot includes an oil outlet. An internal flow channel in the partition is used to supply oil to the oil outlets in the bottom of the two bearing slots, with the openings of the oil outlets facing away from each other along the axial direction of the powertrain.

[0065] In this embodiment of the application, the slots of the two motor slots along the axial direction of the powertrain are opposite to each other. Each motor slot is used to enclose a reducer housing to form a motor cavity, which facilitates the installation of the stator and rotor of a drive motor into the motor cavity from the slots of the two motor slots respectively.

[0066] In this embodiment, the partition includes two bearing grooves with their openings facing away from each other along the axial direction of the powertrain, exposing the two bearing grooves to the two motor cavities respectively, so that they can be fixed to the motor shafts in the two motor cavities respectively. The bottom of each bearing groove includes an oil outlet hole, which allows the oil received by the oil outlet holes of the two bearing grooves to be delivered to the motor shafts in the two motor cavities respectively, so that the oil flows in parallel and the oil flow is split, which can reduce the system oil resistance of the powertrain and reduce power loss.

[0067] In this embodiment, the internal flow channel of the partition is used to deliver oil to the oil outlet holes in the bottom of the two bearing grooves, so that the oil in the internal flow channel of the partition can be diverted through the oil outlet holes in the bottom of the two bearing grooves. The openings of the oil outlet holes of the two bearing grooves are opposite to each other along the axial direction of the powertrain, so that the oil output from the oil outlet holes of the two bearing grooves can be delivered to the motor shaft in the motor cavity on both sides of the partition along the axial direction of the powertrain.

[0068] In one embodiment, the oil outlets of the two bearing grooves respectively deliver oil through nozzles to the through holes in the oil pipe of the motor shaft and the groove opening of the annular groove, so that the oil flowing out of the oil outlets of the bearing grooves can enter the lubrication channel and the cooling channel respectively. This allows the oil in the lubrication channel and the cooling channel to flow relatively independently, which helps to ensure that while one path of oil in the cooling channel can cool the rotor of the drive motor, the other path of oil in the lubrication channel can be delivered along the axial direction of the powertrain to the gear shaft assembly of the reducer to cool and lubricate the sun gear and planetary gears of the reducer.

[0069] Secondly, this application provides an electric vehicle, which includes a frame and a powertrain as described in the first aspect, the frame being used to fix the powertrain, and the powertrain being used to drive wheels via output half-shafts.

[0070] In the powertrain of this application embodiment, cooling channels and lubrication channels are arranged simultaneously in the motor shaft, so that the channel for cooling the rotor of the drive motor and the channel for lubricating the reducer are two separate channels. This ensures that even when the motor shaft is rotating at high speed, the other path of oil flowing in the motor shaft can lubricate the reducer through the lubrication channel, which helps to ensure the normal operation of the reducer and thus improves the overall vehicle performance. Attached Figure Description

[0071] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the embodiments of this application will be described below.

[0072] Figure 1 is a schematic diagram of an electric vehicle provided in an embodiment of this application;

[0073] Figure 2 is a schematic diagram of a powertrain provided in an embodiment of this application;

[0074] Figure 3 is another schematic diagram of the powertrain provided in an embodiment of this application;

[0075] Figure 4 is a schematic diagram of a motor shaft provided in an embodiment of this application;

[0076] Figure 5 is a cross-sectional view of a motor shaft provided in an embodiment of this application;

[0077] Figure 6 is another schematic diagram of the powertrain provided in an embodiment of this application. Detailed Implementation

[0078] The technical solutions of the embodiments of this application will be described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments.

[0079] This application provides a powertrain housing for fixing the stator of a drive motor and accommodating the rotor of the drive motor. The rotor of the drive motor is fixed to the motor shaft of the drive motor, which is used to drive and connect to the input shaft of a reducer. The motor shaft includes a cooling channel and a lubrication channel. The cooling channel is used to deliver one path of oil to the rotor of the drive motor for cooling, and the lubrication channel is used to deliver another path of oil to the reducer for lubrication.

[0080] By simultaneously arranging cooling channels and lubrication channels within the motor shaft, the channels for cooling the rotor of the drive motor and the channels for lubricating the reducer are two separate channels. This ensures that even when the motor shaft rotates at high speed, the other path of oil flowing within the motor shaft can still lubricate the reducer through the lubrication channel, which is beneficial for ensuring the normal operation of the reducer.

[0081] Figure 1 is a schematic diagram of an electric vehicle 1 provided in an embodiment of this application.

[0082] In one embodiment, the electric vehicle 1 includes a frame 10 and a powertrain 20, as shown in FIG1. ​​The frame 10 is used to fix the powertrain 20. In this embodiment, the electric vehicle 1 refers to a wheeled device driven or towed by a power unit. In this embodiment, the powertrain 20 is used to drive the wheels 30.

[0083] Figure 2 is a schematic diagram of one powertrain 20 provided in an embodiment of this application, and Figure 3 is another schematic diagram of the powertrain 20 provided in an embodiment of this application.

[0084] In one embodiment, as shown in Figures 2 and 3, the powertrain 20 includes a power supply unit 100, a drive motor 200, and a reducer 300.

[0085] In this embodiment, the drive motor 200 includes a motor shaft 210, a stator 220, and a rotor 230, while the reducer 300 includes a gear assembly 310. The rotor 230 of the drive motor 200 is fixedly mounted on the motor shaft 210. The stator 220, after receiving AC power from the power supply device 100, drives the rotor 230 to rotate, thereby causing the motor shaft 210 to rotate. The motor shaft 210 of the drive motor 200 transmits kinetic energy to the gear assembly 310 of the reducer 300, and then transmits the power to the wheel 30 through the output half-shaft 40 of the reducer 300, driving the wheel 30 to move.

[0086] In one embodiment, the reducer 300 is a planetary reducer, which includes a sun gear (not shown), multiple planet gears (not shown), multiple planet shafts (not shown), a ring gear (not shown), and a planet carrier (not shown). The sun gear is driven to the motor shaft of the drive motor, and the planet carrier is driven to the output half-shaft 40. The output half-shaft 40 is coaxial with the motor shaft 210 of the drive motor 200. In another embodiment, the planetary reducer includes a two-stage planetary gear system, comprising a sun gear, a first-stage planetary gear, and a second-stage planetary gear. The sun gear is driven to the motor shaft 210 of the drive motor 200, and the sun gear is driven to the output half-shaft 40 through the first-stage and second-stage planetary gears, thus achieving speed change through the two-stage planetary gear system.

[0087] In one embodiment, the reducer 300 is a parallel shaft reducer (not shown), which includes an input shaft (not shown), an intermediate shaft (not shown), and an output shaft (not shown). An input wheel fixed to the input shaft meshes with an intermediate driven wheel fixed to the intermediate shaft, and an intermediate driving wheel fixed to the intermediate shaft meshes with an output wheel fixed to the output shaft. In another embodiment, the output wheel of the reducer 300 is connected to the wheel via a differential and an output half-shaft drive.

[0088] Currently, oil guide pipes and oil holes are usually opened in the motor shaft of the powertrain to cool the rotor of the drive motor and to lubricate the gear shaft assembly of the reducer. However, when the motor shaft rotates at high speed, the lubricating oil in the motor shaft is often thrown out of the oil hole halfway through, and cannot flow to the other end of the shaft to achieve overall cooling and lubrication of the motor shaft, nor can the oil in the motor shaft be transferred to the gear shaft assembly of the reducer for lubrication.

[0089] This application provides a lubrication channel and a cooling channel within the motor shaft, making the channel for cooling the rotor of the drive motor and the channel for lubricating the reducer two separate channels. This ensures that even when the motor shaft is rotating at high speed, the other path of oil flowing within the motor shaft can still lubricate the reducer through the lubrication channel, which is beneficial for ensuring the normal operation of the reducer.

[0090] The powertrain 20 provided in the embodiments of this application will be described in detail below.

[0091] Figure 4 is a schematic diagram of a motor shaft 210 provided in an embodiment of this application, and Figure 5 is a cross-sectional view of a motor shaft 210 provided in an embodiment of this application. In Figure 5, the solid arrows represent one oil path 400, and the dashed arrows represent another oil path 500.

[0092] In one embodiment, as shown in Figures 3 to 5, the housing 20a of the powertrain 20 is used to fix the stator 220 of the drive motor 200 and to house the rotor 230 of the drive motor 200. The rotor 230 of the drive motor 200 is fixed to the motor shaft 210 of the drive motor 200, and the motor shaft 210 of the drive motor 200 is used to drive the input shaft of the reducer 300. The motor shaft 210 includes a cooling channel 211 and a lubrication channel 212. The cooling channel 211 is used to cool the rotor 230 of the drive motor 200 by supplying one path of oil 400, and the lubrication channel 212 is used to lubricate the reducer 300 by supplying another path of oil 500.

[0093] In this embodiment, the rotor 230 of the drive motor 200 is fixed to the motor shaft 210 of the drive motor 200. The motor shaft 210 of the drive motor 200 is used to drive the input shaft of the reducer 300, so that the rotation of the motor shaft 210 of the drive motor 200 can drive the gear shaft assembly 310 of the reducer 300 to rotate, thereby driving the wheel 30.

[0094] In this embodiment, the motor shaft 210 of the drive motor 200 rotates at high speed during operation, generating a large amount of heat. Oil needs to be introduced into the motor shaft 210 to cool it down. A cooling channel 211 and a lubrication channel 212 are simultaneously provided within the motor shaft 210. The cooling channel 211 is used to cool the rotor 230 of the drive motor 200 by supplying one stream of oil 400, while the lubrication channel 212 is used to lubricate the reducer 300 by supplying another stream of oil 500. This allows the oil entering the motor shaft 210 to be divided. One stream of oil 400 cools the rotor 230 of the drive motor 200, preventing the drive motor 200 from malfunctioning due to overheating. The other stream of oil 500 lubricates the gears of the reducer 300, which helps reduce the rotational resistance between the gear shaft assemblies 310 of the reducer 300 and improves the working efficiency of the reducer 300. The cooling channel 211 and the lubrication channel 212 also allow the oil to flow through the entire motor shaft 210, so that the oil can fully cool and lubricate the entire motor shaft 210.

[0095] If the oil is only supplied to the rotor 230 of the drive motor 200 for cooling by setting an oil hole in the motor shaft 210 and throwing oil when the motor shaft 210 rotates, as the rotation speed of the rotor 230 of the drive motor 200 increases, almost all the oil will be thrown out after passing through the oil hole to cool the rotor 230 of the drive motor 200. This will prevent the oil from flowing through the entire motor shaft 210, and consequently, the reducer 300 will not receive the oil supplied from the motor shaft 210. This will increase the heat generated by the reducer 300, reduce the load-bearing capacity of the reducer 300, shorten its service life, and hinder the normal operation of the reducer 300.

[0096] In this embodiment, a lubrication channel 212 and a cooling channel 211 are respectively provided in the motor shaft 210, so that the channel for cooling the rotor 230 of the drive motor 200 and the channel for lubricating the reducer 300 are two separate channels. This ensures that even when the motor shaft 210 is rotating at high speed, the other path of oil flowing in the motor shaft 210 can lubricate the reducer 300 through the lubrication channel 212, which is beneficial to ensuring the normal operation of the reducer 300.

[0097] In one embodiment, as shown in Figures 3 and 5, the flow rate of another oil 500 transported by the lubrication channel 212 is greater than the flow rate of one oil 400 transported by the cooling channel 211 of the motor shaft 210.

[0098] In this embodiment, the flow rate of the other oil 500 transported by the lubrication channel 212 is greater than the flow rate of the oil 400 transported by the cooling channel 211 of the motor shaft 210. This allows more oil in the motor shaft 210 to be used for lubrication of the reducer 300, meeting the lubrication requirements of the reducer 300 at low temperatures and ensuring its normal operation. The smaller flow rate of the oil 400 in the cooling channel 211 is also sufficient to meet the cooling requirements of the rotor 230 of the drive motor 200 at low temperatures.

[0099] In one embodiment, as shown in Figures 3 and 5, the path of another oil 500 flowing through the lubrication channel 212 is greater than the path of one oil 400 flowing through the cooling channel 211.

[0100] Because the drive motor 200 generates significant heat during operation, it is necessary to cool it down promptly to prevent overheating. In this embodiment, the path of the oil 400 flowing through the cooling channel 211 is relatively short, which allows the cooling channel 211 to be shorter than the lubrication channel 212. This brings the cooling channel 211 closer to the rotor 230 of the drive motor 200, making it easier for the oil 400 in the cooling channel 211 to be sprayed more closely onto the rotor 230 of the drive motor 200, thus providing more thorough cooling to the rotor 230. If the path of one oil 400 to the cooling channel 211 is designed to be too long, the time to reach the rotor 230 of the drive motor 200 will be too long, which is not conducive to timely cooling of the rotor 230 of the drive motor 200. Therefore, in this application, the path of the other oil 500 flowing through the lubrication channel 212 is longer than the path of one oil 400 flowing through the cooling channel 211. This allows the reducer 300 to be provided with an independent lubrication channel 212 for lubrication while also being able to cool the drive motor 200 in a timely manner. This improves the working efficiency of the drive motor 200 and enhances the working performance of the reducer 300, thereby improving the overall performance of the powertrain 20.

[0101] In one embodiment, as shown in Figures 3 and 5, the flow rate of the other oil 500 transported by the lubrication channel 212 is greater than the flow rate of the oil 400 transported by the cooling channel 211 of the motor shaft 210, and the path of the other oil 500 flowing through the lubrication channel 212 is greater than the path of the oil 400 flowing through the cooling channel 211. This improves the efficiency of the drive motor 200 and enhances the performance of the reducer 300 even at low ambient temperatures, thereby improving the overall performance of the powertrain 20.

[0102] In one embodiment, as shown in FIG5, the opening orientations of the inlet 212a and outlet 212b of the lubrication channel 212 are opposite to those of the powertrain 20 along the axial direction O, the opening orientation of the inlet 211a of the cooling channel 211 is the same as that of the inlet 212a of the lubrication channel 212, and the opening orientation of the outlet 211b of the cooling channel 211 is parallel to the radial direction R of the powertrain 20.

[0103] In this embodiment, as shown in Figures 3 and 5, the openings of the inlet 212a and outlet 212b of the lubrication channel 212 face away from each other along the axial direction O of the powertrain 20. This allows the other path of oil 500 in the lubrication channel 212 within the motor shaft 210 to be delivered to the reducer 300 more quickly and via a shorter path along the axial direction O of the powertrain 20, thus lubricating the reducer 300 and ensuring its normal operation. Furthermore, it facilitates the machining of the lubrication channel 212 within the motor shaft 210.

[0104] In this embodiment, the opening orientation of the inlet 211a of the cooling channel 211 is the same as the opening orientation of the inlet 212a of the lubrication channel 212, so that the cooling channel 211 and the lubrication channel 212 can simultaneously receive oil flowing into the motor shaft 210, ensuring that the oil in the motor shaft 210 is diverted, and ensuring that oil can flow through both the cooling channel 211 and the lubrication channel 212, so that the rotor 230 of the drive motor 200 can be cooled down while the gear shaft assembly 310 of the reducer 300 can also be fully lubricated. Compared to the design where the opening orientation of the inlet 211a of the cooling channel 211 is different from that of the inlet 212a of the lubrication channel 212, the design where the opening orientation of the inlet 211a of the cooling channel 211 is the same as that of the inlet 212a of the lubrication channel 212 is more conducive to simplifying the channel design. This allows the cooling channel 211 and the lubrication channel 212 to receive oil from the same side, making the oil delivery structure design for the cooling channel 211 and the lubrication channel 212 more focused and simpler.

[0105] In this embodiment, one path of oil 400 in the cooling channel 211 is used to cool the rotor 230 of the drive motor 200. The opening of the outlet 211b of the cooling channel 211 is parallel to the radial direction R of the powertrain 20. The opening of the outlet 211b of the cooling channel 211 is aligned with the direction of the centrifugal force of the motor shaft 210. This makes it easier to throw the oil 400 in the cooling channel 211 out to the rotor 230 of the drive motor 200 through the high-speed rotation of the motor shaft 210, thereby cooling the rotor 230 of the drive motor 200.

[0106] In one embodiment, as shown in FIG5, the inlet 211a of the cooling channel 211 surrounds the outer periphery of the inlet 212a of the lubrication channel 212, and the inlet 211a of the cooling channel 211 and the inlet 212a of the lubrication channel 212 are spaced apart along the radial direction R of the powertrain 20.

[0107] In this embodiment of the application, as shown in Figures 3 and 5, the inlet 211a of the cooling channel 211 surrounds the outer periphery of the inlet 212a of the lubrication channel 212. This allows the lubrication channel 212 to be arranged near the axis of the motor shaft 210, and the cooling channel 211 to be arranged near the outer periphery of the motor shaft 210. This makes it easier for the oil 400 in the cooling channel 211 to be thrown out of the cooling channel 211 by the rotation of the motor shaft 210 to cool the rotor 230 of the drive motor 200.

[0108] In this embodiment, the inlet 211a of the cooling channel 211 and the inlet 212a of the lubrication channel 212 are spaced apart along the radial direction R of the powertrain 20, so that one path of oil 400 in the cooling channel 211 and another path of oil 500 in the lubrication channel 212 can flow relatively independently, thereby ensuring that one path of oil 400 in the motor shaft 210 is used to lubricate the reducer 300, and the other path of oil 500 is used to cool the rotor 230 of the drive motor 200.

[0109] In one embodiment, the cooling channel 211 and the lubrication channel 212 can be integrally machined in the motor shaft 210, thereby increasing the structural strength of the motor shaft 210.

[0110] In one embodiment, the diameter of the inlet 212a of the radial lubrication channel 212 along the powertrain 20 is larger than the width of the inlet 211a of the cooling channel 211.

[0111] In this embodiment, the diameter of the inlet 212a of the radial R lubrication channel 212 along the powertrain 20 is larger than the width of the inlet 211a of the cooling channel 211. This results in a larger volume of oil 500 flowing into the lubrication channel 212 compared to the volume of oil 400 flowing into the cooling channel 211. This ensures that there is enough oil to be delivered to the reducer 300 for lubrication when the environment is at low temperature, which is beneficial to ensuring the normal operation of the reducer 300.

[0112] In this embodiment, the cooling channel 211 is arranged around the lubrication channel 212. The width of the inlet 211a of the cooling channel 211 is set to be small, which helps to keep the motor shaft 210 with a thicker wall, thereby making the motor shaft 210 more reliable.

[0113] In one embodiment, the inlet 211a of the cooling channel 211 surrounds the outer periphery of the inlet 212a of the lubrication channel 212, and the diameter of the inlet 212a of the lubrication channel 212 along the radial direction R of the powertrain 20 is larger than the width of the inlet 211a of the cooling channel 211. In this embodiment, when the inlet 211a of the cooling channel 211 is arranged around the outer periphery of the inlet 212a of the lubrication channel 212, the cooling channel 211 is annular. This allows the flow area of ​​the inlet 211a of the cooling channel 211 to be larger than the flow area of ​​the inlet 212a of the lubrication channel 212, even when the width of the inlet 211a of the cooling channel 211 is smaller than the diameter of the inlet 212a of the lubrication channel 212. This ensures that the lubrication requirements of the reducer 300 can be met while simultaneously cooling the drive motor 200.

[0114] In one embodiment, as shown in FIG5, along the axial direction O of the powertrain 20, the distance between the inlet 211a and the outlet 211b of the cooling channel 211 is smaller than the distance between the inlet 212a and the outlet 212b of the lubrication channel 212.

[0115] In this embodiment of the application, as shown in Figures 3 and 5, along the axial direction O of the powertrain 20, the distance between the inlet 211a and the outlet 211b of the cooling channel 211 is smaller than the distance between the inlet 212a and the outlet 212b of the lubrication channel 212. This allows the length of the cooling channel 211 to be shorter than the length of the lubrication channel 212 along the axial direction O of the powertrain 20. This facilitates the oil flowing through the cooling channel 211 to be closer to the rotor 230 of the drive motor 200, thereby allowing the oil ejected from the outlet 211b of the cooling channel 211 to better cover the rotor 230 of the drive motor 200 and improve the cooling efficiency of the oil 400 on the rotor 230 of the drive motor 200. The large distance between the inlet 212a and outlet 212b of the lubrication channel 212 results in a longer lubrication channel 212, which facilitates the delivery of another path of oil 500 to the reducer 300 located at a more distant end via the motor shaft 210 for lubrication, ensuring the normal operation of the reducer 300.

[0116] In one embodiment, as shown in Figures 3 to 5, the motor shaft 210 further includes a radial flow channel 213. The inlet 213a of the radial flow channel 213 is used to connect to the cooling flow channel 211, and the outlet 213b of the radial flow channel 213 is parallel to the radial direction R of the powertrain 20. The radial flow channel 213 is used to transmit one path of oil 400 output from the cooling flow channel 211 to the rotor 230 of the drive motor 200.

[0117] In this embodiment of the application, the motor shaft 210 further includes a radial flow channel 213. The inlet 213a of the radial flow channel 213 is used to connect to the cooling flow channel 211, so that a path of oil 400 in the cooling flow channel 211 can flow out through the radial flow channel 213 to the rotor 230 of the drive motor 200.

[0118] In this embodiment, the outlet 213b of the radial flow channel 213 is parallel to the radial direction R of the powertrain 20, which makes the length of the radial flow channel 213 shorter. This is more conducive to the motor shaft 210 quickly passing through the radial flow channel 213 during high-speed rotation to throw the oil 400 in the cooling flow channel 211 to the rotor 230 of the drive motor 200, thereby improving the cooling efficiency of the rotor 230 of the drive motor 200.

[0119] In one embodiment, as shown in FIG5, the motor shaft 210 includes two radial flow channels 213, and the distance between the two radial flow channels 213 and the inlet 211a of the cooling flow channel 211 is different along the axial direction of the powertrain 20.

[0120] In this embodiment of the application, as shown in Figures 3 and 5, the motor shaft 210 includes two radial flow channels 213. The distance between the two radial flow channels 213 and the inlet 211a of the cooling flow channel 211 along the axial direction O of the powertrain 20 is different. This allows one path of oil 400 in the cooling flow channel 211 to be thrown out at different positions on the motor shaft 210. This is more conducive to the one path of oil 400 being thrown out having a larger contact area with the rotor 230 of the drive motor 200, which is beneficial to improving cooling efficiency.

[0121] In this embodiment, when the rotational speed of the motor shaft 210 of the drive motor 200 is low, the centrifugal force on one of the oil channels 400 in the cooling channel 211 is small, which makes it easy for the oil in the cooling channel 211 to flow back to the inlet 211a of the cooling channel 211. A radial channel 213 is provided at a position close to the inlet 211a of the cooling channel 211. This is beneficial for the oil to flow through the radial channel 213 and then flow out to the rotor 230 of the drive motor 200, so as to ensure that the rotor 230 of the drive motor 200 has enough oil for cooling.

[0122] In one embodiment, as shown in FIG5, the motor shaft 210 includes a rotating shaft 214 and an oil pipe 215. The rotating shaft 214 includes a shaft cavity 2140, which extends through the motor shaft 210 along the axial direction of the powertrain 20. The shaft cavity 2140 is used to accommodate and fix the oil pipe 215. The oil pipe 215 includes a through hole 2510, which extends through the oil pipe 215 along the axial direction of the powertrain 20. The through hole 2510 is used to form a lubrication channel 212.

[0123] In this embodiment of the application, as shown in Figures 3 and 5, the motor shaft 210 includes a rotating shaft 214 and an oil pipe 215. The rotating shaft 214 includes a shaft cavity 2140, which extends through the motor shaft 210 along the axial direction of the powertrain 20, allowing the oil pipe 215 to be arranged within the shaft cavity 2140 of the rotating shaft 214. Dividing the motor shaft 210 into a rotating shaft 214 and an oil pipe 215 also facilitates the machining of the lubrication channel 212 and simplifies the machining process.

[0124] In this embodiment, the through hole 2510 of the oil pipe 215 extends through the oil pipe 215 along the axial direction O of the powertrain 20, which facilitates the direct machining of the through hole 2510 in the oil pipe 215 to form a lubrication channel 212. It also allows the lubrication channel 212 to be parallel to the axial direction O of the powertrain 20, thereby enabling the other path of oil 500 in the lubrication channel 212 to be transmitted to the reducer 300 located on the side of the drive motor 200 at a faster speed and shorter distance, so as to lubricate the gear shaft assembly 310 of the reducer 300, which is beneficial to ensuring the normal operation of the reducer 300.

[0125] In one embodiment, as shown in FIG5, the oil passage 215 further includes an annular groove 2151. The annular groove 2151 extends from the end face of one end 2153 of the oil passage 215 towards the other end 2154 of the oil passage 215 along the axial direction O of the powertrain 20. The annular groove 2151 surrounds the through hole 2510 and is used to form a cooling channel 211. The groove opening 2152 of the annular groove 2151 is the inlet 211a of the cooling channel 211. The groove wall 2155 of the annular groove 2151 includes a connecting hole 2156. The connecting hole 2156 extends through the groove wall 2155 of the annular groove 2151 along the radial direction R of the powertrain 20. The connecting hole 2156 is the outlet 211b of the cooling channel 211.

[0126] In this embodiment of the application, the oil pipe 215 further includes an annular groove 2151. The annular groove 2151 is recessed from the end face of one end 2153 of the oil pipe 215 towards the other end 2154 of the oil pipe 215 along the axial direction O of the power assembly 20, thereby facilitating the machining of the annular groove 2151 from one end 2153 of the oil pipe 215, or facilitating the demolding of the annular groove 2151 from the other end 2154 of the oil pipe 215.

[0127] In this embodiment of the application, as shown in Figures 3 and 5, an annular groove 2151 surrounds the through hole 2510. The annular groove 2151 is used to form a cooling channel 211, so that the cooling channel 211 can be arranged around the lubrication channel 212 of the through hole 2510. It can also make the cooling channel 211 in the annular groove 2151 and the lubrication channel 212 in the through hole 2510 deliver oil relatively independently. This ensures that one path of oil 400 input into the oil pipe 215 can be used to cool the rotor 230 of the drive motor 200, avoiding overheating and failure of the drive motor 200. Another path of oil 500 can be used to lubricate the reducer 300, which helps to ensure the normal operation of the reducer 300.

[0128] In this embodiment, the opening 2152 of the annular groove 2151 is the inlet 211a of the cooling channel 211, allowing a stream of oil 400 to flow into the cooling channel 211 through the opening 2152 of the annular groove 2151. The groove wall 2155 of the annular groove 2151 includes a connecting hole 2156, which penetrates the groove wall 2155 of the annular groove 2151 along the radial direction of the powertrain 20. The connecting hole 2156 is the outlet 211b of the cooling channel 211, allowing a stream of oil 400 in the cooling channel 211 to be discharged from the annular groove 2151 through the connecting hole 2156 on the groove wall 2155 of the annular groove 2151, for cooling the rotor 230 of the drive motor 200.

[0129] In this embodiment, the connecting hole 2156 penetrates the groove wall 2155 of the annular groove 2151 along the radial direction R of the powertrain 20. This also facilitates the direct machining of the connecting hole 2156 from the oil pipe 215 along the radial direction R of the powertrain 20, and allows the connecting hole 2156 to have a shorter length, which facilitates faster oil ejection when the motor shaft 210 rotates at high speed. Furthermore, it allows the oil to be sprayed along the radial direction R of the powertrain 20, thereby spraying more oil onto the rotor 230 of the drive motor 200, which is beneficial for improving cooling efficiency.

[0130] In one embodiment, the cooling channel 211 can be formed by the outer wall of the oil pipe 215 and the inner wall of the rotating shaft 214, simplifying the formation process of the cooling channel 211.

[0131] In one embodiment, the cooling channel 211 and the lubrication channel 212 are integrally formed in the motor shaft 210. In another embodiment, the motor shaft 210 is an integral structure.

[0132] In one embodiment, as shown in Figures 3 and 5, the housing 20a of the powertrain 20 includes a bearing groove 610 for fixing the outer ring of a bearing 800, and the inner ring of the bearing 800 for fixing to a motor shaft 210. The groove opening 611 of the bearing groove 610 faces the rotor 230 of the drive motor 200 along the axial direction O of the powertrain 20. The bottom 612 of the bearing groove 610 includes an oil outlet 613, the opening of which faces the rotor 230 of the drive motor 200 along the axial direction O of the powertrain 20. The oil outlet 613 is used to output oil to at least one of the cooling channel 211 and the lubrication channel 212.

[0133] In this embodiment, the slot 611 of the bearing groove 610 faces the rotor 230 of the drive motor 200 along the axial direction O of the powertrain 20, which makes it easier to fix the bearing 800 in the bearing groove 610 to the motor shaft 210.

[0134] In this embodiment, the bottom 612 of the bearing groove 610 includes an oil outlet 613. The opening of the oil outlet 613 faces the rotor 230 of the drive motor 200 along the axial direction O of the powertrain 20. This allows the oil output from the oil outlet 613 to flow directly toward the rotor 230 of the drive motor 200, making the oil output from the oil outlet 613 flow more smoothly toward the rotor 230 of the drive motor 200. It also helps to bring the oil outlet 613 closer to the rotor 230 of the drive motor 200, allowing the rotor 230 of the drive motor 200 to be cooled down by the oil more quickly, which is beneficial to improving the cooling efficiency of the drive motor 200.

[0135] In this embodiment, the oil outlet 613 is used to output oil to at least one of the cooling channel 211 and the lubrication channel 212, so that the oil output from the oil outlet 613 can enter the motor shaft 210 and be split within the motor shaft 210. One path of oil 400 flowing to the cooling channel 211 can be used to cool the rotor 230 of the drive motor 200, and the other path of oil 500 flowing to the lubrication channel 212 can be used to lubricate the gear shaft assembly 310 of the reducer 300, which helps to ensure the normal operation of the reducer 300.

[0136] In one embodiment, oil is supplied to both the cooling channel 211 and the lubrication channel 212 through a single oil outlet 613, simplifying the oil supply structure. In another embodiment, the bottom 612 of the bearing groove 610 includes two oil outlets 613, which supply oil to the cooling channel 211 and the lubrication channel 212 respectively. This allows for more precise control of the flow rates in the cooling channel 211 and the lubrication channel 212, resulting in better cooling of the rotor 230 of the drive motor 200 and better lubrication of the reducer 300, thereby improving the working efficiency of the powertrain 20 cooling and lubrication system.

[0137] In one embodiment, the inlet of the cooling channel 211 or the lubrication channel 212 is embedded in the oil outlet 613. In another embodiment, the oil outlet 613 is embedded in the inlet of the cooling channel 211 or the lubrication channel 212. A gap exists between the inlet of the cooling channel 211 or the lubrication channel 212 and the oil outlet 613, allowing the inlet of the cooling channel 211 or the lubrication channel 212 to rotate relative to the oil outlet 613, thus preventing the oil outlet 613 from affecting the rotation of the motor shaft 210.

[0138] In one embodiment, as shown in Figures 3 and 5, an oil outlet 613 along the axial direction of the powertrain 20 is spaced from an inlet 211a, 212a of at least one of the cooling channel 211 and the lubrication channel 212. The oil outlet 613 is used to fix a nozzle 700, which is used to deliver the oil output from the oil outlet 613 to the cooling channel 211 or the lubrication channel 212.

[0139] In this embodiment of the application, the oil outlet 613 along the axial direction of the powertrain 20 is spaced apart from the inlet 211a, 212a of at least one of the cooling channel 211 and the lubrication channel 212, so that there is space between the oil outlet 613 and the cooling channel 211 and the lubrication channel 212 for arranging the nozzle 700.

[0140] In this embodiment, the oil outlet 613 is used to fix the nozzle 700. The nozzle 700 is used to transport the oil output from the oil outlet 613 to the cooling channel 211 or the lubrication channel 212. By setting the nozzle 700 in the oil outlet 613, the oil flowing out of the oil outlet 613 can be divided by the nozzle 700 and flow to the cooling channel 211 or the lubrication channel 212 respectively, so that there is oil in the motor shaft 210, thereby facilitating the cooling of the rotor 230 of the drive motor 200 or the lubrication of the reducer 300.

[0141] In one embodiment, the nozzle 700 includes two outlets that supply oil to the cooling channel 211 and the lubrication channel 212, respectively.

[0142] In one embodiment, as shown in Figures 3 and 5, the housing 20a encloses the reducer housing 320 to form a motor cavity 240, which accommodates the stator 220 and rotor 230 of the drive motor 200. The reducer housing 320 accommodates the gear shaft assembly 310 of the reducer 300. The reducer housing 320 includes a through hole 321 that extends through the reducer housing 320 along the axial direction O of the motor shaft 210. The through hole 321 passes through one end 216 of the motor shaft 210, which extends into the reducer housing 320. The outlet 212b of the lubrication channel 212 is distributed at one end 216 of the motor shaft 210, which is used to drive at least one gear of the reducer 300.

[0143] In this embodiment, the housing 20a is used to enclose the reducer housing 320 to form the motor cavity 240, so that the formation of the motor cavity 240 can be achieved by using the reducer housing 320, which is beneficial to making the housing 20a of the powertrain 20 more integrated.

[0144] In this embodiment, the reducer housing 320 includes a through hole 321 that extends through the reducer housing 320 along the axial direction O of the motor shaft 210. This creates conditions for one end 216 of the motor shaft 210 to pass through the through hole 321 and extend into the reducer housing 320. The extension of one end 216 of the motor shaft 210 into the reducer housing 320 further facilitates the lubrication channel 212 within the motor shaft 210 in delivering another path of oil 500 to the gear shaft assembly 310 of the reducer 300 for lubrication.

[0145] In this embodiment, the outlet 212b of the lubrication channel 212 is located at one end 216 of the motor shaft 210. One end 216 of the motor shaft 210 extends into the reducer housing 320, allowing the other path of oil 500 in the lubrication channel 212 to be directly sprayed into the reducer housing 320. The other end 216 of the motor shaft 210 is used to drive at least one gear of the reducer 300, making the outlet 212b of the lubrication channel 212 closer to at least one gear of the reducer 300. This facilitates spraying the other path of oil 500 from the lubrication channel 212 onto the gear shaft assembly 310 of the reducer 300, and more accurately delivers the other path of oil 500 to the gear shaft assembly 310 of the reducer 300 for lubrication.

[0146] Among them, the axial direction O of the motor shaft 210 is in the same direction as the axial direction O of the powertrain 20.

[0147] In one embodiment, as shown in Figures 3 and 5, the reducer 300 includes a sun gear 311, a planet carrier 312, and a plurality of planet gears 313. One end 216 of the motor shaft 210 is used to drive the sun gear 311. The plurality of planet gears 313 are distributed around the outer periphery of the sun gear 311 along the circumferential direction C of the motor shaft 210. The outlet 212b of the lubrication channel 212 along the axial direction O of the powertrain 20 is exposed to the sun gear 311. Another path of oil 500 output from the outlet 212b of the lubrication channel 212 is used to cool the plurality of planet gears 313.

[0148] In this embodiment, one end 216 of the motor shaft 210 is used to drive the sun gear 311. Multiple planetary gears 313 are distributed around the outer periphery of the sun gear 311 along the circumferential direction C of the motor shaft 210, so that the power of the drive motor 200 can be transmitted to the sun gear 311 of the reducer 300 through the motor shaft 210, driving the sun gear 311 of the reducer 300 to rotate. The sun gear 311 then transmits the power to the multiple planetary gears 313, causing the multiple planetary gears 313 to move as well, thereby driving the output half shaft 40 to drive the wheel 30.

[0149] In this embodiment, the outlet 212b of the lubrication channel 212 along the axial direction O of the powertrain 20 is exposed to the sun gear 311. This ensures that when the motor shaft 210 rotates at high speed, the oil flowing out from the outlet 212b of the lubrication channel 212 will not hit the shaft cavity 2140 of the motor shaft 210, but can be directly thrown out of the motor shaft 210. This also makes it easier for the other oil 500 in the lubrication channel 212 to lubricate the sun gear 311 and the multiple planetary gears 313 located around the sun gear 311 along the radial direction R of the powertrain 10 when the motor shaft 210 rotates.

[0150] In this embodiment, the other oil 500 output from the outlet 212b of the lubrication channel 212 is used to cool the multiple planetary gears 313, which helps to ensure the normal operation of the multiple planetary gears 313.

[0151] In one embodiment, when the length of the outlet 212b of the lubrication channel 212 is insufficient to be exposed to the sun gear 311, a nozzle can be connected to the outlet 212b of the lubrication channel 212 to ensure that the other oil 500 output from the outlet 212b of the lubrication channel 212 can be directly sprayed onto the gear shaft assembly 310 of the reducer 300 to fully lubricate the gear shaft assembly 310 of the reducer 300.

[0152] In one embodiment, when the reducer 300 includes two stages of planetary gears, the outlet 212b of the lubrication channel 212 along the axial direction of the powertrain 20 is distributed between the two stages of planetary gears, and the lubrication channel 212 lubricates the two stages of planetary gears.

[0153] Figure 6 is another schematic diagram of the powertrain 20 provided in an embodiment of this application.

[0154] In one embodiment, as shown in Figures 5 and 6, the powertrain 20 includes two drive motors 200 and two reducers 300. The two drive motors 200 are arranged between the two reducers 300. The powertrain 20 includes two reducer housings 320. The housing 20a includes a partition 600, which divides the housing 20a into two motor slots 250. The slot openings of the two motor slots 250 are opposite to each other along the axial direction O of the powertrain 20. Each motor slot 250 is used to enclose a reducer housing 320 to form a motor cavity 240. The partition 600 includes two bearing slots 610. The slot openings 611 of the two bearing slots 610 are opposite to each other along the axial direction O of the powertrain 20. The bottom 612 of each bearing slot 610 includes an oil outlet 613. The internal flow channel 620 of the partition 600 is used to deliver oil to the oil outlet 613 in the bottom 612 of the two bearing grooves 610, and the openings of the oil outlet 613 of the two bearing grooves 610 are opposite to each other along the axial direction O of the powertrain 20.

[0155] In this embodiment, the slots of two motor slots 250 are opposite to each other along the axial direction O of the powertrain 20. Each motor slot 250 is used to enclose a reducer housing 320 to form a motor cavity 240, which facilitates the installation of the stator 220 and rotor 230 of a drive motor 200 into the motor cavity 240 from the slots of the two motor slots 250 respectively.

[0156] In this embodiment, the partition 600 includes two bearing grooves 610. The groove openings 611 of the two bearing grooves 610 are opposite to each other along the axial direction O of the powertrain 20, so that the two bearing grooves 610 are respectively exposed in the two motor cavities 240, and can be fixed to the motor shafts 210 in the two motor cavities 240 respectively. The bottom 612 of each bearing groove 610 includes an oil outlet hole 613, which allows the oil received by the oil outlet holes 613 of the two bearing grooves 610 to be respectively delivered to the motor shafts 210 in the two motor cavities 240, so that the oil is diverted and flows in parallel, which can reduce the system oil resistance of the powertrain 20 and reduce power loss.

[0157] In this embodiment, the internal flow channel of the partition 600 is used to deliver oil to the oil outlet 613 in the bottom 612 of the two bearing grooves 610, so that the oil in the internal flow channel 620 of the partition 600 can be diverted through the oil outlet 613 in the bottom 612 of the two bearing grooves 610. The openings of the oil outlet 613 of the two bearing grooves 610 face opposite directions along the axial direction O of the powertrain 20, so that the oil output from the oil outlet 613 of the two bearing grooves 610 can be delivered to the motor shaft 210 in the motor cavity 240 on both sides of the partition 600 along the axial direction O of the powertrain 20.

[0158] In one embodiment, as shown in Figures 5 and 6, the oil outlets 613 of the two bearing grooves 610 respectively deliver oil through nozzles 700 to the through holes 2510 and the slots 2152 of the annular groove 2151 in the oil pipe 215 of the motor shaft 210. This allows the oil flowing out of the oil outlets 613 of the bearing grooves 610 to enter the lubrication channel 212 and the cooling channel 211 respectively. This allows the oil in the lubrication channel 212 and the cooling channel 211 to flow relatively independently. This helps to ensure that while one path of oil 400 in the cooling channel 211 can cool the rotor 230 of the drive motor 200, the other path of oil 500 in the lubrication channel 212 can be delivered along the axial direction O of the powertrain 20 to the gear shaft assembly 310 of the reducer 300 to cool and lubricate the sun gear 311 and planetary gear 313 of the reducer 300.

[0159] In one embodiment, the nozzle 700 may include a plurality of sub-nozzles 710. The orifice diameter of the sub-nozzle 710 used to deliver another path of oil 500 to the lubrication channel 212 is larger than that of the sub-nozzle 710 used to deliver one path of oil 400 to the cooling channel 211. This allows more oil output from the oil outlet 613 of the bearing groove 610 to flow to the reducer 300, providing sufficient lubrication to the gear shaft assembly 310 of the reducer 300 and ensuring the normal operation of the reducer 300.

[0160] The powertrain and electric vehicle provided in the embodiments of this application have been described in detail above. Specific examples have been used to illustrate the principles and embodiments of this application. The description of the embodiments above is only for the purpose of helping to understand the method and core ideas of this application. At the same time, for those skilled in the art, there will be changes in specific embodiments and application scope based on the ideas of this application. Therefore, the content of this specification should not be construed as a limitation of this application.

Claims

1. A powertrain, characterized in that, The powertrain housing is used to fix the stator of the drive motor and to house the rotor of the drive motor. The rotor of the drive motor is fixed to the motor shaft of the drive motor, and the motor shaft of the drive motor is used for transmission connection to the input shaft of the reducer, wherein: The motor shaft includes a cooling channel and a lubrication channel. The cooling channel is used to cool the rotor of the drive motor by supplying one path of oil, and the lubrication channel is used to supply another path of oil to the reducer for lubrication.

2. The powertrain according to claim 1, characterized in that, The flow rate of the other oil path used to transport the lubrication channel is greater than the flow rate of the oil path used to transport the cooling channel of the motor shaft; and / or The path of the other oil flow through the lubrication channel is longer than the path of the other oil flow through the cooling channel.

3. The powertrain according to claim 1 or 2, characterized in that, The inlet and outlet openings of the lubrication channel are oriented opposite to each other along the axial direction of the powertrain, the inlet opening of the cooling channel is oriented in the same direction as the inlet opening of the lubrication channel, and the outlet opening of the cooling channel is oriented parallel to the radial direction of the powertrain.

4. The powertrain according to claim 3, characterized in that, The inlet of the cooling channel surrounds the outer periphery of the inlet of the lubrication channel, and the inlet of the cooling channel and the inlet of the lubrication channel are radially spaced apart from each other along the powertrain.

5. The powertrain according to claim 3, characterized in that, Along the axial direction of the powertrain, the distance between the inlet and outlet of the cooling channel is smaller than the distance between the inlet and outlet of the lubrication channel.

6. The powertrain according to any one of claims 1-5, characterized in that, The motor shaft also includes a radial flow channel, the inlet of which is used to connect to the cooling flow channel, the outlet of which is parallel to the radial direction of the powertrain, and the radial flow channel is used to transmit one path of oil output from the cooling flow channel to the rotor of the drive motor.

7. The powertrain according to claim 6, characterized in that, The motor shaft includes two radial flow channels, and the distance between the two radial flow channels and the inlet of the cooling flow channel is different along the axial direction of the powertrain.

8. The powertrain according to any one of claims 1-7, characterized in that, The motor shaft includes a rotating shaft and an oil pipe. The rotating shaft includes a shaft cavity that extends through the motor shaft along the axial direction of the power assembly. The shaft cavity is used to accommodate and fix the oil pipe. The oil pipe includes a through hole that extends through the oil pipe along the axial direction of the power assembly. The through hole is used to form the lubrication channel.

9. The powertrain according to claim 8, characterized in that, The oil passage pipe also includes an annular groove, which is recessed from one end face of the oil passage pipe toward the other end along the axial direction of the powertrain. The annular groove surrounds the through hole and forms the cooling channel. The groove opening of the annular groove is the inlet of the cooling channel. The groove wall of the annular groove includes a connecting hole, which penetrates the groove wall of the annular groove along the radial direction of the powertrain. The connecting hole is the outlet of the cooling channel.

10. The powertrain according to any one of claims 1-9, characterized in that, The powertrain housing includes a bearing groove for fixing the outer ring of the bearing, and the inner ring of the bearing for fixing to the motor shaft. The opening of the bearing groove faces the rotor of the drive motor along the axial direction of the powertrain, wherein: The bottom of the bearing groove includes an oil outlet hole, the opening of which is axially toward the rotor of the drive motor along the powertrain, and the oil outlet hole is used to output oil to at least one of the cooling channel and the lubrication channel.

11. The powertrain according to claim 10, characterized in that, Along the axial direction of the powertrain, the oil outlet is spaced from the inlet of at least one of the cooling channel and the lubrication channel. The oil outlet is used to fix a nozzle, which is used to deliver the oil output from the oil outlet to the cooling channel or the lubrication channel.

12. The powertrain according to claim 10, characterized in that, The housing is used to enclose the reducer housing to form a motor cavity, the motor cavity is used to accommodate the stator and rotor of the drive motor, the reducer housing is used to accommodate the gear shaft assembly of the reducer, the reducer housing includes a through hole, the through hole extends through the reducer housing along the axial direction of the motor shaft, the through hole is used to pass through one end of the motor shaft, the end of the motor shaft passing through the through hole extends into the reducer housing, the outlet of the lubrication channel is distributed at the one end of the motor shaft, and the one end of the motor shaft is used to drive at least one gear of the reducer.

13. The powertrain according to claim 12, characterized in that, The reducer includes a sun gear, a planet carrier, and multiple planet gears. One end of the motor shaft is used for transmission connection to the sun gear. The multiple planet gears are distributed circumferentially around the sun gear along the motor shaft. The outlet of the lubrication channel is exposed on the sun gear along the axial direction of the power assembly. Another path of oil output from the outlet of the lubrication channel is used to cool the multiple planet gears.

14. The powertrain according to claim 12, characterized in that, The powertrain includes two drive motors and two reducers. The two drive motors are arranged between the two reducers. The powertrain includes two reducer housings. Each housing includes a partition that divides the housing into two motor slots. The openings of the two motor slots are opposite to each other along the axial direction of the powertrain. Each motor slot encloses one reducer housing to form a motor cavity. The partition includes two bearing slots. The openings of the two bearing slots are opposite to each other along the axial direction of the powertrain. The bottom of each bearing slot includes an oil outlet hole. The internal flow channel of the partition is used to supply oil to the oil outlet holes in the bottom of the two bearing grooves, and the openings of the oil outlet holes in the two bearing grooves are oriented opposite to each other along the axial direction of the powertrain.

15. An electric vehicle, characterized in that, The electric vehicle includes a frame and a powertrain as described in any one of claims 1-14, the frame being used to secure the powertrain, the powertrain being used to drive wheels via output half-shafts.

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