Oil-cooled electric drive assembly and new energy electric vehicle

Abstract

The application discloses an oil-cooled electric drive assembly and a new energy electric vehicle, and belongs to the technical field of electric drive. The oil-cooled electric drive assembly comprises a main shell, a speed reducer assembly, a motor assembly, an oil storage pool and an oil pump, wherein the motor assembly comprises a rotating shaft, a rotor and a stator. The rotor is sleeved on the rotating shaft, the rotating shaft and the input shaft of the speed reducer assembly both have a hollow structure, one end of the rotating shaft is communicated with the input shaft, and the other end is communicated with the cavity of the main shell; the outer wall of the stator has an annular oil channel and two oil injection rings, the two oil injection rings are communicated with the annular oil channel respectively, and the oil injection rings are used for injecting oil along the radial direction of the stator; the oil storage pool is communicated with the main shell; and the oil pump is communicated with the oil storage pool, the annular oil channel and the input shaft respectively. By adopting the scheme, the oil liquid directly cools the heat source, that is, there is no thermal resistance between the oil liquid and the stator and the rotor, which is favorable for improving the heat dissipation effect of the stator and the rotor, thereby, the reliability and stability of the oil-cooled electric drive assembly during operation are ensured.

Description

Technical Field

[0001] This application relates to the field of electric drive technology, and in particular to an oil-cooled electric drive assembly and a new energy electric vehicle. Background Technology

[0002] Currently, the mainstream new energy vehicles include pure electric vehicles and hybrid vehicles. Among them, pure electric vehicles have the advantage of zero emissions. Moreover, as the driving range of pure electric vehicles continues to improve and charging facilities become more and more complete, pure electric vehicles are taking up an increasingly larger proportion of the entire automotive industry.

[0003] Currently, the mainstream pure electric vehicles on the market are generally powered by a "three-in-one" electric drive assembly that integrates a motor, a reducer, and a controller. When a pure electric vehicle is running, the motor generates a significant amount of heat. Currently, water cooling is commonly used to dissipate this heat; that is, a water-cooled radiator is installed outside the motor housing to remove heat from the housing and thus cool the motor.

[0004] In an electric motor, the components that generate heat are the stator and rotor, which are located inside the housing. Water-cooled radiators are located outside the housing and can only indirectly dissipate heat from the stator and rotor through the housing. They cannot directly cool the heat source. There is thermal resistance between the water-cooled radiator and the stator and rotor, resulting in low heat dissipation efficiency. In severe cases, this can cause the motor to malfunction. Summary of the Invention

[0005] This application provides an oil-cooled electric drive assembly and a new energy electric vehicle, which solves the problem in related technologies where water-cooled radiators cannot directly cool the heat source, resulting in low heat dissipation efficiency due to thermal resistance between the water-cooled radiator and the stator and rotor. The technical solution is as follows: In a first aspect, this application provides an oil-cooled electric drive assembly, which includes a main housing, a reducer assembly, a motor assembly, an oil reservoir, and an oil pump, wherein the motor assembly includes a rotating shaft, a rotor, and a stator; The reducer assembly is located inside the main housing and is connected to the main housing; The rotating shaft is located inside the main housing and on one side of the reducer assembly, and is connected to the input shaft of the reducer assembly. Both the rotating shaft and the input shaft have a hollow structure. One end of the rotating shaft is connected to the input shaft, and the other end of the rotating shaft is connected to the cavity of the main housing. The rotor is sleeved on the rotating shaft and connected to the rotating shaft; The stator is sleeved outside the rotor and has a gap between them. It is connected to the main housing. The outer wall of the stator has an annular oil passage and two oil injection rings. The two oil injection rings are located on the outer wall of the stator and at both ends of the stator axial direction, and are respectively connected to the annular oil passage. The oil injection rings are used to spray oil along the radial direction of the stator. The oil storage tank is located at the bottom outside the main shell, and is connected to and communicates with the main shell; The oil pump is located outside the main housing and is connected to the oil storage tank, the annular oil passage, and the input shaft, respectively.

[0006] In one possible implementation, the rotating shaft includes a first shaft segment, a second shaft segment, and a third shaft segment; One end of the first shaft segment is connected to the input shaft; The second shaft segment is located at the end of the first shaft segment away from the input shaft. The hollow area of ​​the second shaft segment forms an oil storage cavity, which is connected to the other end of the first shaft segment. The rotor is sleeved on the second shaft segment and connected to the second shaft segment. The third shaft segment is located at the end of the second shaft segment away from the first shaft segment. One end of the third shaft segment is connected to the oil storage cavity, and the other end of the third shaft segment is connected to the cavity of the main housing.

[0007] In one possible implementation, at least a portion of the first shaft segment is located within the oil reservoir.

[0008] In one possible implementation, the motor assembly further includes two end face oil sprayers; The two end-face oil sprayers are fitted on the second shaft section and located on both sides of the rotor axis, and are respectively connected to the oil storage cavity. The end-face oil sprayers are used to spray oil radially along the second shaft section.

[0009] In one possible implementation, the motor assembly further includes an oil injection block; The oil injection block is located in the hollow area of ​​the third shaft section and is spaced from the other end of the third shaft section. The oil injection block is used to inject oil into the resolver mechanism in the motor assembly.

[0010] In one possible implementation, the stator outer wall has multiple axial oil passages; A portion of the plurality of axial oil passages is located between the annular oil passage and one of the injection rings, and is connected to the annular oil passage and one of the injection rings respectively; Another portion of the plurality of axial oil passages is located between the annular oil passage and another injection ring, and is connected to the annular oil passage and the other injection ring, respectively.

[0011] In one possible implementation, a portion of the plurality of axial oil passages are distributed at equal intervals along the circumferential direction of the stator outer wall, and another portion of the plurality of axial oil passages are distributed at equal intervals along the circumferential direction of the stator outer wall.

[0012] In one possible implementation, the oil-cooled electric drive assembly further includes an oil filter; The oil filter is located outside the main housing and is connected to the oil pump, the annular oil passage, and the input shaft.

[0013] In one possible implementation, the oil-cooled electric drive assembly further includes an oil cooler; The oil cooler is located outside the main housing and is connected to the oil filter, the annular oil passage, and the input shaft, respectively.

[0014] Secondly, this application provides a new energy electric vehicle, which includes an oil-cooled electric drive assembly as described in any one of the first aspects and its possible implementations.

[0015] The beneficial effects of the technical solutions provided in this application are: In the solution provided in this application embodiment, as the oil flows back to the oil reservoir through the annular oil passage, the injection ring, the outer ring of the stator winding, and the bottom of the main housing, it carries away the heat generated by the stator winding, thus directly dissipating heat from the stator. Similarly, as the oil flows back to the oil reservoir through the input shaft, the rotating shaft, and the bottom of the main housing, it carries away the heat generated by the rotor, thus directly dissipating heat from the rotor. This solution directly cools the heat source, eliminating thermal resistance between the oil and the stator and rotor, which improves heat dissipation for both the stator and rotor. This, in turn, helps ensure the reliability and stability of the oil-cooled electric drive assembly during operation.

[0016] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and do not limit this application. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of the structure of an oil-cooled electric drive assembly provided in an embodiment of this application; Figure 2This is a cross-sectional structural schematic diagram of an oil-cooled electric drive assembly provided in an embodiment of this application; Figure 3 This is a partial structural schematic diagram of an oil-cooled electric drive assembly provided in an embodiment of this application; Figure 4 This is a partial cross-sectional structural diagram of an oil-cooled electric drive assembly provided in an embodiment of this application; Figure 5 This is a schematic diagram of an oil circuit structure provided in an embodiment of this application.

[0019] Legend 1. Main housing; 2. Reducer assembly; 3. Motor assembly; 4. Oil reservoir; 5. Oil pump; 6. Oil filter; 7. Oil cooler; 21. Input shaft; 31. Rotating shaft; 32. Rotor; 33. Stator; 34. End face oil spray; 311. First shaft section; 312. Second shaft section; 313. Third shaft section; 331. Annular oil passage; 332. Injection ring; 333. Axial oil passage; 312A, Oil storage chamber. Detailed Implementation

[0020] Unless otherwise defined, the technical or scientific terms used herein shall have the ordinary meaning understood by one of ordinary skill in the art to which this disclosure pertains. The terms “first,” “second,” “third,” and similar terms used in this patent application specification and claims do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Similarly, the terms “an” or “a” and similar terms do not indicate a quantity limitation, but rather indicate the presence of at least one. The terms “comprising” or “including” and similar terms mean that the element or object preceding “comprising” or “including” encompasses the element or object listed following “comprising” or “including” and its equivalents, and do not exclude other elements or objects. The terms “connected” or “linked” and similar terms are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. The terms “upper,” “lower,” “left,” “right,” etc., are used only to indicate relative positional relationships, and these relative positional relationships may change accordingly when the absolute position of the described object changes.

[0021] To make the objectives, technical solutions, and advantages of this application clearer, the embodiments of this application will be described in further detail below with reference to the accompanying drawings.

[0022] Currently, the mainstream new energy vehicles include pure electric vehicles and hybrid vehicles. Among them, pure electric vehicles have the advantage of zero emissions. Moreover, as the driving range of pure electric vehicles continues to improve and charging facilities become more and more complete, pure electric vehicles are taking up an increasingly larger proportion of the entire automotive industry.

[0023] Currently, the mainstream pure electric vehicles on the market are generally powered by a "three-in-one" electric drive assembly that integrates a motor, a reducer, and a controller. When a pure electric vehicle is running, the motor generates a significant amount of heat. Currently, water cooling is commonly used to dissipate this heat; that is, a water-cooled radiator is installed outside the motor housing to remove heat from the housing and thus cool the motor.

[0024] With the development and popularization of new energy vehicles, the market's requirements for the power performance of pure electric vehicles are constantly increasing, and the requirements for the size and power density of the electric drive assembly are also becoming higher. This requires the power system layout to be as compact and lightweight as possible. Furthermore, there are high requirements for the heat dissipation capacity of the motor in the electric drive assembly. Using a water-cooling solution has at least the following disadvantages: Disadvantage 1: In an electric motor, the components that generate heat are the stator and rotor, which are located inside the housing. However, the water-cooled radiator is located outside the housing, so it can only indirectly dissipate heat from the stator and rotor through the housing and cannot directly cool the heat source. There is thermal resistance between the water-cooled radiator and the stator and rotor, resulting in low heat dissipation efficiency.

[0025] Disadvantage 2: The water-cooling solution requires the water-cooling radiator to be placed outside the casing and a water jacket structure to be placed inside the casing to prevent short circuits, which increases the size and weight of the electric drive assembly and cannot meet the current market demand for lightweighting.

[0026] Therefore, this application provides an oil-cooled electric drive assembly. New energy electric vehicles using this assembly can achieve good heat dissipation and also promote the lightweight development of electric drive assemblies. The following is a description of an oil-cooled electric drive assembly provided in this application.

[0027] Figure 1 This is a schematic diagram of the structure of an oil-cooled electric drive assembly provided in an embodiment of this application. Figure 2 This is a cross-sectional structural schematic diagram of an oil-cooled electric drive assembly provided in an embodiment of this application. (Reference) Figure 1 and Figure 2 As shown, the oil-cooled electric drive assembly includes a main housing 1, a reducer assembly 2, a motor assembly 3, an oil reservoir 4, and an oil pump 5. The motor assembly 3 includes a rotating shaft 31, a rotor 32, and a stator 33.

[0028] The main housing 1 has an internal cavity, and the reducer assembly 2 is located inside and connected to the main housing 1. The reducer assembly 2 includes an input shaft 21, an output shaft, and at least two stages of reduction gears. The input shaft 21 is used to connect to the rotating shaft 31 in the motor assembly 3, the output shaft is used to drive external devices (such as couplings) to rotate, and the at least two stages of reduction gears are used to achieve the speed reduction effect between the input shaft 21 and the output shaft. No specific limitations are made here regarding the specific structure of the reducer assembly 2.

[0029] refer to Figure 2 As shown, the motor assembly 3's rotating shaft 31 is located inside the main housing 1 and on one side of the reducer assembly 2. The rotating shaft 31 is connected to the input shaft 21 of the reducer assembly 2. The rotating shaft 31 and the input shaft 21 can be connected via a spline. No restrictions are placed on the connection method between the rotating shaft 31 and the input shaft 21, as long as they can move synchronously. Both the rotating shaft 31 and the input shaft 21 have hollow structures. One end of the rotating shaft 31 is connected to the input shaft 21, and the other end is connected to the cavity of the main housing 1 (i.e., the interior of the main housing 1).

[0030] In the motor assembly 3, the rotor 32 is mounted on the shaft 31 and is fixedly connected to the shaft 31. The rotor 32 and the shaft 31 can be connected by means of key connection, interference fit, etc. The connection relationship between the rotor 32 and the shaft 31 is not limited here.

[0031] In the motor assembly 3, the stator 33 is sleeved outside the rotor 32, and there is a gap (i.e., an air gap) between the stator 33 and the rotor 32. Specifically, the inner wall of the stator 33 is opposite to the outer wall of the rotor 32 and there is a gap. The stator 33 is connected to the inner wall of the main housing 1 to ensure the stability of the stator 33. The connection method between the stator 33 and the main housing 1 is not limited here.

[0032] As an example, Figure 3 This is a partial structural schematic diagram of an oil-cooled electric drive assembly provided in an embodiment of this application, as shown below. Figure 3As shown, the stator 33 has an annular oil passage 331 and two oil injection rings 332 on its outer wall. The oil injection rings 332 have a hollow annular structure, and their inner walls (the surface near the shaft 31) have multiple nozzles for spraying oil. The two oil injection rings 332 are located on the outer wall of the stator 33 at both ends of the stator 33's axial direction, and are connected to the annular oil passage 331. The oil injection rings 332 spray oil radially along the stator 33. The oil sprayed from the oil injection rings 332 flows over the surface of the stator windings in the stator 33, thereby carrying away the heat generated on the stator windings to achieve heat dissipation for the stator 33. The axial direction of the stator 33 is parallel to the extension direction of the shaft 31's axis, and the radial direction of the stator 33 is perpendicular to the extension direction of the shaft 31's axis.

[0033] refer to Figure 1 and Figure 2 As shown, the oil reservoir 4 is located at the bottom of the outer side of the main housing 1, that is, at the outer wall of the main housing 1 in the direction of gravity. The oil reservoir 4 is connected to the main housing 1 to ensure the stability of the oil reservoir 4 in the oil-cooled electric drive assembly, and the oil reservoir 4 is in communication with the main housing 1. Optionally, the oil reservoir 4 may not be connected to the main housing 1, but it is necessary to ensure that the oil reservoir 4 is in communication with the cavity of the main housing 1, thereby ensuring that the oil in the main housing 1 can flow back to the oil reservoir 4 along the inner wall of the main housing 1. As an example, the surface of the main housing 1 that contacts the oil reservoir 4 has at least one through hole, through which the oil in the main housing 1 can flow back to the oil reservoir 4.

[0034] refer to Figure 1 and Figure 2 As shown, the oil pump 5 is located outside the main housing 1 and is connected to the oil reservoir 4, the annular oil passage 331, and the input shaft 21. The oil pump 5 is used to transport the oil from the oil reservoir 4 to the outside and to ensure the circulation of the oil within the oil-cooled electric drive assembly. The oil pump 5 may or may not be connected to the main housing 1. The fact that both the oil pump 5 and the oil reservoir 4 are located outside the main housing 1 facilitates maintenance, repair, or replacement of the oil pump 5 and the oil reservoir 4, and helps maintain the stability and reliability of the oil-cooled electric drive assembly during operation.

[0035] In this scheme, a certain amount of oil is pre-stored in the oil reservoir 4. This oil can be an oil with both lubricating and cooling effects. Before, during, or after the oil-cooled electric drive assembly starts working, the oil pump 5 is turned on. The oil pump 5 continuously draws oil from the oil reservoir 4 and delivers oil to the annular oil passage 331 on the outer wall of the stator 33 and the input shaft 21 in the reducer assembly 2, forming two branches.

[0036] The oil flow process of one branch is as follows: Under the action of oil pump 5, the oil in the annular oil circuit 331 will reach the oil injection rings 332 on both sides of the stator 33, and the oil injection rings 332 will spray the oil along the radial direction of the stator 33 to the outer ring of the stator winding of the stator 33. The oil in the outer ring of the stator winding will flow to the bottom of the main housing 1 under the action of gravity, and then flow back to the oil storage tank 4 from the bottom of the main housing 1.

[0037] The oil flow process in the other branch is as follows: Under the action of the oil pump 5, the oil in the input shaft 21 will flow to the rotating shaft 11, and flow from the other end of the rotating shaft 11 into the cavity of the main housing 1, and finally flow back to the oil storage tank 4 from the bottom of the main housing 1.

[0038] In the solution provided in this application embodiment, during the process of the oil flowing back to the oil storage tank 4 through the annular oil passage 331, the oil injection ring 332, the outer ring of the stator winding, and the bottom of the main housing 1, the oil carries away the heat generated by the stator winding, thus directly dissipating heat from the stator 33. Similarly, during the process of the oil flowing back to the oil storage tank 4 through the input shaft 21, the rotating shaft 31, and the bottom of the main housing 1, the oil carries away the heat generated by the rotor 32, thus directly dissipating heat from the rotor 32. Using this solution, the oil directly cools the heat source, meaning there is no thermal resistance between the oil and the stator 33 and rotor 32. This improves the heat dissipation effect on the stator 33 and rotor 32, thereby ensuring the reliability and stability of the oil-cooled electric drive assembly during operation.

[0039] Figure 4 This is a partial cross-sectional structural schematic diagram of an oil-cooled electric drive assembly provided in an embodiment of this application. In some examples, reference is made to... Figure 3 and Figure 4 As shown, the rotating shaft 31 includes a first shaft segment 311, a second shaft segment 312 and a third shaft segment 313. The first shaft segment 311, the second shaft segment 312 and the third shaft segment 313 are coaxial and all have a hollow structure.

[0040] The first shaft segment 311 is located on one side of the input shaft 21, and one end of the first shaft segment 311 is connected to the input shaft 21. As an example, the first shaft segment 311 is connected to the input shaft 21 by a spline.

[0041] The second shaft segment 312 is located at the end of the first shaft segment 311 furthest from the input shaft 21 and is connected to the first shaft segment 311. The second shaft segment 312 and the first shaft segment 311 can be integrally formed or fixedly connected by welding or other methods. The hollow area of ​​the second shaft segment 312 forms an oil storage cavity 312A, which is connected to the other end of the first shaft segment 311. In some examples, the rotor 32 is sleeved on the second shaft segment 312 and connected to it. Furthermore, the radial dimension of the oil storage cavity 312A is larger than the radial dimension of the first shaft segment 311. Therefore, after the oil enters the oil storage cavity 312A from the first shaft segment 311, the flow rate decreases, which is beneficial for the oil to fully exchange heat with the rotor 32, thereby improving the heat exchange effect on the rotor 32.

[0042] As an example, refer to Figure 4 As shown, at least a portion of the first shaft segment 311 is located within the oil storage cavity 312A. One end of the first shaft segment 311 located in the oil storage cavity 312A is sealed, while the side wall of the portion of the first shaft segment 311 located in the oil storage cavity 312A has at least one through hole, which is used to communicate with the oil storage cavity 312A through the hollow region of the first shaft segment 311.

[0043] The third shaft segment 313 is located at the end of the second shaft segment 312 furthest from the first shaft segment 311 and is connected to the second shaft segment 312. The third shaft segment 313 and the second shaft segment 312 can be integrally formed or fixedly connected by welding or other methods. One end of the third shaft segment 313 is connected to the oil storage cavity 312A, and the other end of the third shaft segment 313 is connected to the cavity of the main housing 1 to realize the circulation of oil.

[0044] As an example, refer to Figure 4 As shown, the radial dimension of the hollow region of the second shaft section 312 (i.e., the oil storage chamber 312A) is greater than the radial dimension of the hollow region of the first shaft section 311 and the radial dimension of the hollow region of the third shaft section 313. This scheme is beneficial to controlling the flow rate of the oil in the oil storage chamber 312A and to enabling the oil to fully exchange heat with the rotor 32, thereby improving the heat exchange effect on the rotor 32.

[0045] In some examples, reference Figure 4As shown, the motor assembly 3 also includes two end-face oil sprayers 34, each with a ring-shaped structure. The two end-face oil sprayers 34 are fitted onto the second shaft section 312 of the rotating shaft 31, and are located on opposite sides of the rotor 32's axial direction. Each end-face oil sprayer 34 is connected to the second shaft section 312. The end-face oil sprayers 34 can be integrally formed with the second shaft section 312, or they can be fixed by welding or riveting. Each end-face oil sprayer 34 has a hollow structure, and multiple spray holes are provided on its outer wall (i.e., the surface away from the second shaft section 312) to spray oil. The two end-face oil sprayers 34 are connected to the oil storage chamber 312A, thus ensuring that when the rotating shaft 31 rotates, the end-face oil sprayers 34 spray oil radially along the second shaft section 312 under the action of centrifugal force.

[0046] Under the action of oil pump 5, the oil in input shaft 21 flows to oil storage chamber 312A of second shaft section 312. The oil in oil storage chamber 312A forms two oil path branches: one oil path branch is where the oil in oil storage chamber 312A exchanges heat with rotor 32, then flows to third shaft section 313, and finally flows back to oil storage tank 4 through the bottom of main housing 1; the other oil path branch is where the oil in oil storage chamber 312A is sprayed out through end face oil spray 34 and reaches the inner ring of stator winding of stator 33, carrying away the heat at the inner ring of stator winding, and finally flows back to oil storage tank 4 through the bottom of main housing 1. This scheme allows the oil to exchange heat with the inner ring of stator winding of stator 33 and carry away a certain amount of heat, thereby improving the heat dissipation effect of stator 33.

[0047] In some examples, reference Figure 4 As shown, the motor assembly 3 also includes an oil injection block 35. The oil injection block 35 is located within the hollow region of the third shaft segment 313 and is spaced from the other end of the third shaft segment 313. Specifically, the oil injection block 35 is spaced from the end of the third shaft segment 313 furthest from the second shaft segment 312. As an example, the oil injection block 35 corresponds radially to the resolver mechanism in the motor assembly 3. After the oil flows through the oil injection block 35, it can spray a portion of the oil onto the resolver mechanism in the motor assembly 3, thereby achieving heat dissipation for the resolver mechanism. Furthermore, by spraying oil onto the resolver mechanism, the oil injection block 35 can control the flow rate and volume of the oil flowing from the third shaft segment 313 to the cavity of the main housing 1, which helps to avoid insufficient cooling caused by oil pressure fluctuations.

[0048] Figure 5 This is a schematic diagram of an oil circuit structure provided in an embodiment of this application. (Reference) Figure 4 and Figure 5As shown, the outer wall of the stator 33 has multiple axial oil passages 333. A portion of the multiple axial oil passages 333 is located between an annular oil passage 331 and an injection ring 332, and each axial oil passage 333 is connected to both the annular oil passage 331 and the aforementioned injection ring 332. Another portion of the multiple axial oil passages 333 is located between the annular oil passage 331 and another injection ring 332, and each axial oil passage 333 is connected to both the annular oil passage 331 and the aforementioned injection ring 332. Under the action of the oil pump 5, the oil in the annular oil passage 331 reaches the injection rings 332 on both sides through the multiple axial oil passages 333 on both sides of the annular oil passage 331, thereby ensuring that the injection rings 332 inject oil radially along the stator 33.

[0049] As an example, refer to Figure 5 As shown, a portion of the aforementioned plurality of axial oil passages 333 are distributed at equal intervals along the circumferential direction of the outer wall of the stator 33, and another portion of the aforementioned plurality of axial oil passages 333 are distributed at equal intervals along the circumferential direction of the outer wall of the stator 33. Optionally, the plurality of axial oil passages 333 located on the same side of the annular oil passage 331 may be non-uniformly distributed, such as sinusoidal distribution, etc. The distribution method of the axial oil passages 333 is not limited here.

[0050] In some examples, reference Figure 2 and Figure 5 As shown, the oil-cooled electric drive assembly also includes an oil filter 6. The oil filter 6 is located outside the main housing 1 and can be detachably connected to the main housing 1 for easy maintenance or replacement. The oil filter 6 is connected to the oil pump 5, the annular oil passage 331, and the input shaft 21. Under the action of the oil pump 5, the oil pump 5 draws oil from the oil reservoir 4 and first reaches the oil filter 6. After being filtered by the oil filter 6, the oil flows to the annular oil passage 331 and the input shaft 21.

[0051] By adopting this solution, the oil filter 6 can filter out impurities such as rust carried in the oil, which helps to ensure the purity of the oil and thus prevents damage to the components in the oil-cooled electric drive assembly. In turn, it helps to improve the working stability and service life of the oil-cooled electric drive assembly.

[0052] In some examples, reference Figure 2 and Figure 5As shown, the oil-cooled electric drive assembly also includes an oil cooler 7. The oil cooler 7 is located outside the main housing 1 and can be detachably connected to the main housing 1 for easy maintenance or replacement. The oil cooler 7 is connected to the oil filter 6, the annular oil passage 331, and the input shaft 21. Under the action of the oil pump 5, the oil pump 5 draws oil from the oil reservoir 4, first reaching the oil filter 6. After being filtered by the oil filter 6, the oil reaches the oil cooler 7. The circulating water passage in the oil cooler 7 cools the oil, and the cooled oil reaches the annular oil passage 331 and the input shaft 21. As an example, the temperature of the oil before cooling is between 90°C and 95°C, and the temperature of the cooled oil is between 80°C and 85°C. Optionally, the oil cooler 7 can also cool the oil to below 80°C; this is only an example to illustrate the cooling effect of the oil cooler 7 and no specific assumptions are made.

[0053] By adopting this solution, the cooled oil can absorb more heat, which is beneficial to improving the heat dissipation effect on the rotor 32 and stator 33, thereby improving the reliability and stability of the oil-cooled electric drive assembly during operation.

[0054] In some examples, the connection between the components in this application embodiment is achieved through a tubular structure. For example, an oil pipe is provided between the oil pump 5 and the oil filter 6, the annular oil passage 331 on the outer wall of the stator 33 is also a tubular structure, the axial oil passage 333 on the outer wall of the stator 33 is also a tubular structure, and so on.

[0055] In other examples, the oil passages between components in this embodiment are achieved by machining grooves or holes in the components. For instance, the oil pump 5 and the oil filter 6 are connected by a through hole in the main housing 1; the annular oil passage 331 on the outer wall of the stator 33 is formed by an annular groove on the outer wall of the stator 33 and the inner wall of the main housing 1; the connection between the oil storage chamber 312A of the second shaft segment 312 and the end face oil spray is achieved by machining a through hole in the second shaft segment 312, and so on. This approach reduces the number of tubular structures connecting the components, reduces the number of parts in the oil-cooled electric drive assembly, facilitates further optimization of the size and structure of the oil-cooled electric drive assembly, and reduces costs.

[0056] In the solution provided in this application embodiment, during the process of the oil flowing back to the oil storage tank 4 through the annular oil passage 331, the oil injection ring 332, the outer ring of the stator winding, and the bottom of the main housing 1, the oil carries away the heat generated by the stator winding, thus directly dissipating heat from the stator 33. Similarly, during the process of the oil flowing back to the oil storage tank 4 through the input shaft 21, the rotating shaft 31, and the bottom of the main housing 1, the oil carries away the heat generated by the rotor 32, thus directly dissipating heat from the rotor 32. Using this solution, the oil directly cools the heat source, meaning there is no thermal resistance between the oil and the stator 33 and rotor 32. This improves the heat dissipation effect on the stator 33 and rotor 32, thereby ensuring the reliability and stability of the oil-cooled electric drive assembly during operation.

[0057] Based on the same technical concept, embodiments of this application also provide a new energy electric vehicle, which includes any of the oil-cooled electric drive assemblies provided in the embodiments of this application. Using the oil-cooled electric drive assembly provided in the embodiments of this application is beneficial for improving the heat dissipation effect on the stator and rotor during the operation of the new energy electric vehicle, thereby helping to ensure the reliability and stability of the new energy electric vehicle.

[0058] The above description is merely an optional embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. An oil-cooled electric drive assembly, characterized in that, It includes a main housing, a reducer assembly, a motor assembly, an oil reservoir, and an oil pump. The motor assembly includes a shaft, a rotor, a stator, and two end face oil sprayers. The reducer assembly is located inside the main housing and is connected to the main housing; The rotating shaft is located inside the main housing, on one side of the reducer assembly, and connected to the input shaft of the reducer assembly. Both the rotating shaft and the input shaft have hollow structures. One end of the rotating shaft is connected to the input shaft, and the other end of the rotating shaft is connected to the cavity of the main housing. The rotor is sleeved on the rotating shaft and connected to the rotating shaft; The stator is sleeved outside the rotor, with a gap between them, and is connected to the main housing. The outer wall of the stator has an annular oil passage and two oil injection rings. The two oil injection rings are located on the outer wall of the stator at both ends of the stator axial direction and are respectively connected to the annular oil passage for spraying oil along the radial direction of the stator. The oil storage tank is located at the bottom outside the main shell, connected to and communicating with the main shell; The oil pump is located outside the main housing and is connected to the oil reservoir, the annular oil passage, and the input shaft. The rotating shaft includes a first shaft section, a second shaft section, and a third shaft section; one end of the first shaft section is connected to the input shaft; the second shaft section is located at the end of the first shaft section away from the input shaft, and the hollow area of ​​the second shaft section forms an oil storage cavity, which is connected to the other end of the first shaft section; the rotor is sleeved on the second shaft section and connected to it; the third shaft section is located at the end of the second shaft section away from the first shaft section, one end of the third shaft section is connected to the oil storage cavity, and the other end of the third shaft section is connected to the cavity of the main housing; at least a portion of the first shaft section is located within the oil storage cavity. Two end-face oil spray sleeves are installed on the second shaft section, located on both sides of the rotor axis, and are respectively connected to the oil storage chamber for radial oil spraying along the second shaft section.

2. The oil-cooled electric drive assembly according to claim 1, characterized in that, The motor assembly also includes an oil injection block; The oil injection block is located in the hollow area of ​​the third shaft section and is spaced from the other end of the third shaft section. The oil injection block is used to inject oil into the resolver mechanism in the motor assembly.

3. The oil-cooled electric drive assembly according to claim 1, characterized in that, The stator outer wall has multiple axial oil passages; A portion of the multiple axial oil passages is located between an annular oil passage and an injection ring, and is connected to the annular oil passage and an injection ring respectively; Another part of the multiple axial oil passages is located between the annular oil passage and another injection ring, and is connected to the annular oil passage and another injection ring respectively.

4. The oil-cooled electric drive assembly according to claim 3, characterized in that, A portion of the multiple axial oil passages are distributed at equal intervals along the circumferential direction of the stator outer wall, and another portion of the multiple axial oil passages are distributed at equal intervals along the circumferential direction of the stator outer wall.

5. The oil-cooled electric drive assembly according to claim 1, characterized in that, The oil-cooled electric drive assembly also includes an oil filter; The oil filter is located outside the main housing and is connected to the oil pump, the annular oil passage, and the input shaft.

6. The oil-cooled electric drive assembly according to claim 5, characterized in that, The oil-cooled electric drive assembly also includes an oil cooler; The oil cooler is located outside the main housing and is connected to the oil filter, the annular oil passage, and the input shaft.

7. A new energy electric vehicle, characterized in that, New energy electric vehicles include the oil-cooled electric drive assembly as described in any one of claims 1-6.

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