Cooling structure of stator core, oil-cooled motor, and vehicle

Abstract

This utility model provides a cooling structure for a stator core, an oil-cooled motor, and a vehicle, belonging to the field of automotive technology. The stator core has back-to-back U-shaped oil channels, with two oil outlets facing the ends of the stator windings. The stator core has an oil inlet connected to the U-shaped oil channels. Cooling medium enters the U-shaped oil channels from the oil inlet and then is directly sprayed onto the ends of the stator windings through the oil outlets. This application directly sets up U-shaped oil channels inside the stator core, ensuring uniform distribution of the cooling medium within the oil-cooled motor, preventing localized overheating, improving the reliability of the oil-cooled motor, and significantly enhancing its heat dissipation performance and operational stability. It also benefits the overall layout and lightweight design of new energy vehicles.

Description

Technical Field

[0001] This utility model belongs to the field of automotive technology, and more specifically, it relates to a cooling structure for a stator core, an oil-cooled motor, and a vehicle. Background Technology

[0002] Traditional oil-cooled motors typically use injection rings or injection pipes to spray cooling oil onto the stator windings, which presents the following problems:

[0003] (1) Complex structure: Traditional oil-cooled motors rely on independent components such as oil injection rings or oil injection pipes, which require additional fixed brackets, seals and complex assembly processes, increasing the number of parts and increasing manufacturing and maintenance costs; the assembly process is cumbersome and is prone to seal failure or oil leakage due to process errors; it is not conducive to the overall vehicle layout and lightweight design.

[0004] (2) Uneven cooling: The oil circuit design of the oil injection ring or oil injection pipe cannot cover the stator winding end area, resulting in uneven distribution of cooling oil. The stator end windings are overheated locally due to uneven heat dissipation, which accelerates insulation aging. Temperature gradient differences cause thermal stress concentration, reducing motor life. During high-power operation, local overheating may trigger the safety protection mechanism, limiting motor performance. Utility Model Content

[0005] The purpose of this utility model is to provide a cooling structure for the stator core, an oil-cooled motor, and a vehicle, aiming to solve the problems caused by the complex structure and uneven cooling of traditional oil-cooled motors.

[0006] To achieve the above objectives, the technical solution adopted by this utility model is: to provide a cooling structure for a stator core, wherein a U-shaped oil guide channel is arranged back-to-back inside the stator core, and the two oil outlets of the U-shaped oil guide channel are both facing the end of the stator winding;

[0007] The stator core is provided with an oil inlet that connects to the U-shaped oil guide channel;

[0008] The cooling medium entering the U-shaped oil guide channel is directly sprayed onto the end of the stator winding through the oil outlet.

[0009] The beneficial effects of the stator core cooling structure provided by this utility model are as follows:

[0010] (1) Simple structure: This application directly sets the oil guide channel on the stator core, and directly sets the core oil inlet and oil outlet on the stator core. The cooling of the stator winding does not need to rely on the oil injection ring or oil injection pipe, nor does it need additional fixed brackets and seals. The simple structure greatly reduces the number of parts and reduces the manufacturing and maintenance costs. The simple structure also simplifies the assembly process and can avoid the problem of seal failure or oil leakage caused by process assembly errors.

[0011] This type of stator core, with fewer components and a simpler structure, is compact, occupies less space, and is also conducive to the lightweighting and overall layout of the vehicle.

[0012] (2) Uniform cooling: This application sets up U-shaped oil guide channels back to back on the stator core. There are two oil outlets in the axial region of the stator winding end. That is, the cooling medium sprayed by the two oil outlets with different positions on the same diameter will cover different areas, so as to completely cover the axial region of the stator winding end, improve the uniformity of cooling and heat dissipation effect of the stator winding end, avoid excessive local temperature rise at the stator winding end, and the resulting thermal stress concentration caused by temperature gradient difference, which accelerates insulation aging and reduces the service life of the motor. It also avoids the problem of local overheating triggering the safety protection mechanism when the motor is running at high power, thus limiting the performance of the motor.

[0013] Currently, setting a straight oil guide channel on the stator core can solve the problem of complex traditional structures. However, this cooling method only has one oil outlet at each end of the stator core. This application sets a U-shaped oil guide channel back to back on the stator core, with four oil outlets at each end of the stator core. The stator winding end at the same end has two corresponding oil outlets along the axial region, which greatly improves the heat dissipation and cooling effect of the stator winding.

[0014] (3) Reduced flow resistance and energy consumption: The U-shaped oil guide channels set back to back on the stator core in this application are provided with an oil inlet and two oil outlets on each U-shaped oil guide channel. This shortens the flow time of the cooling medium in the U-shaped oil guide channel, reduces the flow resistance of the cooling medium, and increases the flow speed of the cooling medium, thereby improving the cooling and heat dissipation effect. The smooth flow of the cooling medium avoids the energy consumption caused by the pump pressure needing to overcome the flow resistance, thereby reducing energy consumption and also benefiting the improvement of motor power.

[0015] In conjunction with the first aspect, in one possible implementation, the stator core includes a first core group, a second core group, a third core group, a fourth core group, and a fifth core group located on the vertical bisector along the axial length.

[0016] The U-shaped oil guide channels are symmetrically arranged along the vertical bisector; the fifth iron core group isolates the symmetrically arranged U-shaped oil guide channels.

[0017] The U-shaped oil guide channel extends axially to the first iron core assembly to form the oil outlet;

[0018] The oil inlet of the iron core can be optionally located on the first iron core group, the second iron core group, the third iron core group, or the fourth iron core group.

[0019] In the above technical solution, the stator core itself is composed of several core laminations stacked together. In this application, the stator core is distinguished according to the different positions of the internal oil guiding channels, and symmetrically arranged U-shaped oil guiding channels are set on the symmetrical stator core. Each U-shaped oil guiding channel is provided with an oil inlet for the core. The distance and flow rate of the cooling medium to the stator winding end in the U-shaped oil guiding channel are the same, so that the stator winding ends at both ends of the stator core receive the same sprayed cooling medium, thereby ensuring the consistency of cooling and heat dissipation of the stator winding ends at both ends and avoiding the influence of local temperature difference, local overheating and other influencing factors.

[0020] In conjunction with the first aspect, in one possible implementation, the first core assembly includes a first core lamination, on which first oil guide holes are uniformly distributed on a first pitch circle near its outer edge, and on which second oil guide holes are uniformly distributed on a second pitch circle near its teeth, the first oil guide holes and the second oil guide holes correspond one-to-one; the first oil guide holes and the second oil guide holes constitute the oil outlet and form part of the U-shaped oil guide channel.

[0021] In the above technical solution, the first oil guide hole is located on the periphery of the first iron core lamination, which serves to prevent the cooling medium from stagnating and forming a dead zone.

[0022] In conjunction with the first aspect, in one possible implementation, the second core assembly includes a second core lamination, the outer diameter of which is smaller than the outer diameter of the first core lamination, and forms the core oil inlet; third oil guide holes are evenly distributed on the third pitch circle near the teeth of the second core lamination, the third oil guide holes are connected to the second oil guide holes one by one, and form part of the U-shaped oil guide channel.

[0023] In the above technical solution, the outer diameter of the second iron core group is smaller than that of the first iron core lamination and other iron core laminations. The second iron core group is stacked between the first iron core group and the third iron core group. Due to the small outer diameter, an annular notch is formed, which directly serves as the iron core oil inlet. It can be seen that the iron core oil inlet does not need to be set up separately.

[0024] In conjunction with the first aspect, in one possible implementation, the third core assembly includes a third core lamination, on which a fourth oil guide hole is uniformly distributed on a fourth pitch circle near its outer edge. The fourth oil guide hole overlaps with the core oil inlet in the axial direction to form a connection, and the fourth oil guide hole is offset towards the center of the stator core.

[0025] The fifth oil guide hole is evenly distributed on the fifth pitch circle near the teeth of the third iron core lamination. The fifth oil guide hole and the third oil guide hole partially overlap along the axial direction to form a connection, and the fifth oil guide hole is offset away from the center of the stator iron core.

[0026] The fourth oil guide hole and the fifth oil guide hole constitute the bottom variable cross-section portion of the U-shaped oil guide channel.

[0027] In the above technical solution, the bottom variable cross-section of the U-shaped oil guide channel formed on the third iron core group allows the cooling medium to pass smoothly at the bend through the bottom variable cross-section design, avoiding the generation of flow resistance which would reduce the flow velocity of the cooling medium, increase the energy consumption of the pump supplying the cooling medium, and increase the energy consumption of the motor.

[0028] In conjunction with the first aspect, in one possible implementation, the third core group includes a plurality of third core laminations; the fourth oil guide holes on adjacent third core laminations are arranged radially offset, the fifth oil guide holes on adjacent third core laminations are arranged radially offset, and the radial distance between the fourth oil guide hole and the corresponding fifth oil guide hole gradually decreases towards the fifth core group, forming the bottom variable cross-section portion.

[0029] In the above technical solution, when the third core group includes multiple third core laminations, since each oil guide hole on the third core lamination is punched out in one go by a mold, and the center line of each oil guide hole is parallel to the axis of the stator core, the distance between the fourth oil guide hole and the fifth oil guide hole on each third core lamination is inconsistent. That is, to ensure the connection between adjacent fourth oil guide holes, the distance between the fourth oil guide hole and the fifth oil guide hole must be gradually reduced to form a bottom variable cross section. Therefore, the multiple fourth oil guide holes formed by the multiple third core laminations are stepped channels, and the multiple fifth oil guide holes are also stepped.

[0030] In conjunction with the first aspect, in one possible implementation, the diameter of the fourth oil guide hole is the same as the diameter of the fifth oil guide hole, and is larger than the diameter of the first oil guide hole.

[0031] In the above technical solution, the flow resistance of the cooling medium is reduced by enlarging the oil guide hole, especially the flow resistance at the bend, thereby reducing energy consumption and improving heat dissipation.

[0032] In conjunction with the first aspect, in one possible implementation, the fourth core assembly includes a fourth core lamination, and the fourth core lamination is provided with a connecting hole that connects the fourth oil guide hole and the fifth oil guide hole. The elongated hole on the fourth core lamination connecting the fourth oil guide hole and the fifth oil guide hole allows the cooling medium to flow from one core inlet to two outlets.

[0033] Secondly, this utility model embodiment also provides an oil-cooled motor, including the aforementioned cooling structure for the stator core.

[0034] This application provides an oil-cooled motor that, through a U-shaped oil guide channel directly disposed inside the stator core, can not only directly cool the stator core and the ends of the stator windings, but also eliminates the need for redundant oil spraying and sealing structure designs. Therefore, the oil-cooled motor provided by this application has fewer redundant structures, a compact structure, small size, and occupies less space, and can significantly reduce manufacturing and maintenance costs. It also benefits the overall layout and lightweight design of new energy vehicles.

[0035] The U-shaped oil guide channel ensures that the cooling medium is evenly distributed in the oil-cooled motor, avoids local overheating, improves the reliability of the oil-cooled motor operation, and significantly enhances the motor's heat dissipation performance and operational stability.

[0036] Thirdly, this utility model embodiment also provides a vehicle including the aforementioned stator core cooling structure.

[0037] The vehicle provided by this utility model, by utilizing this stator core cooling structure, can improve the uniformity of cooling of the oil-cooled motor, significantly improve the heat dissipation performance and operational stability of the motor, thereby reducing the failure rate of the whole vehicle, improving the operational stability of the whole vehicle, and also significantly reducing manufacturing and maintenance costs. It is also beneficial to the overall layout and lightweight design of new energy vehicles. Attached Figure Description

[0038] To more clearly illustrate the technical solutions in the embodiments of this utility model, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0039] Figure 1 A schematic diagram of the flow path of the oil-sprayed cooling medium at both ends of the stator core provided in this embodiment of the utility model;

[0040] Figure 2 A three-dimensional structural schematic diagram of the stator core and windings provided for embodiments of this utility model;

[0041] Figure 3 A three-dimensional structural diagram of the stator core provided in an embodiment of this utility model;

[0042] Figure 4 A cross-sectional view of the stator core along the axis provided in this embodiment of the utility model (showing the U-shaped oil guide channel).

[0043] Figure 5 A cross-sectional view of the stator core along the axis provided for an embodiment of this utility model (arrows indicate the direction of the cooling medium).

[0044] Figure 6 A three-dimensional structural diagram of oil spraying at both ends of the stator core provided for an embodiment of this utility model;

[0045] Figure 7 An exploded view of the stator core provided in an embodiment of this utility model;

[0046] Figure 8 A schematic diagram of the structure of the first iron core lamination provided in an embodiment of this utility model;

[0047] Figure 9 This is a schematic diagram of the structure of the second iron core lamination provided in an embodiment of the present invention;

[0048] Figure 10 This is a schematic diagram of the structure of the third connecting iron core lamination provided in an embodiment of the present utility model;

[0049] Figure 11 A schematic diagram of the structure of the third iron core lamination provided in this embodiment of the utility model;

[0050] Figure 12 A schematic diagram of the structure of the fourth iron core lamination provided in this embodiment of the present invention;

[0051] Figure 13 A schematic diagram of the structure of the fifth iron core lamination provided in an embodiment of this utility model;

[0052] In the diagram: 1. Housing; 11. Oil inlet channel; 12. Branch oil channel; 13. Main oil inlet; 2. Stator core; 21. U-shaped oil guide channel; 22. Oil outlet; 23. First core assembly; 231. First oil guide hole; 232. Second oil guide hole; 233. First core lamination; 24. Second core assembly; 241. Core oil inlet; 242. Third oil guide hole; 243. Second core lamination; 25. Third core assembly; 251. Fourth oil guide hole; 252. Sixth oil guide hole; 253. Seventh oil guide hole; 254. Third connecting core lamination; 255. Fifth oil guide hole; 256. Third core lamination; 26. Fourth core assembly; 261. Connecting hole; 262. Fourth core lamination; 27. Fifth core assembly; 271. Fifth core lamination; 3. Stator winding end. Detailed Implementation

[0053] To make the technical problems, technical solutions, and beneficial effects of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present utility model and are not intended to limit the present utility model.

[0054] It should be noted that when an element is referred to as being "set on" another element, it can be directly on or indirectly on that other element. It should be understood that the terms "length," "width," "upper," "lower," "front," "rear," "top," "bottom," "inner," and "outer," etc., indicating orientation or positional relationships, are based on the orientation or positional relationships shown in the accompanying drawings and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model.

[0055] The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature.

[0056] It should be noted that the directions or positional relationships indicated by "front", "rear", "inner", "outer", "up", and "down" in this embodiment are based on the vehicle's own orientation. The front of the vehicle represents "front", the rear of the vehicle represents "rear", the top of the vehicle represents "up", the bottom of the vehicle represents "down", the "inner" side refers to the side facing the driver's cab, and the "outer" side refers to the side facing the driver's cab.

[0057] In addition, the front-rear direction of the vehicle body defined in the embodiments of this utility model refers to the front-rear direction of the vehicle's forward direction during driving; the left-right direction of the vehicle body defined refers to the left-right direction of the vehicle's forward direction during driving; and the up-down direction of the vehicle body defined refers to the up-down direction of the vehicle's forward direction during driving.

[0058] In this application, the axial direction refers to the direction of the axis of the stator core, the radial direction refers to the direction of the diameter of the stator core, and the circumferential direction is the pitch circle formed by the center of the stator core.

[0059] Please refer to the following: Figures 1-13The cooling structure of the stator core provided by this utility model will now be described. The stator core 2 has U-shaped oil channels 21 arranged back-to-back inside, with two oil outlets 22 facing the stator winding end 3. The stator core 2 has an oil inlet 241 communicating with the U-shaped oil channels 21. The cooling medium enters the U-shaped oil channels 21 from the oil inlet 241 and then is directly sprayed onto the stator winding end 3 through the oil outlets 22.

[0060] Explained, the above embodiment is a description based on the structure shown in a certain axial section of the stator core 2. In this defined axial section, two pairs of U-shaped oil guide channels 21 are arranged back-to-back inside the stator core 2. The two pairs of U-shaped oil guide channels 21 are symmetrically arranged along the axis of the stator core 2. In this embodiment, during the description... Figure 1 The U-shaped oil guiding channels 21 shown in the text are all described using a pair of U-shaped oil guiding channels 21 above the axis of the stator core 2 as an example.

[0061] Since the stator core 2 has several back-to-back U-shaped oil channels 21 evenly distributed in the circumferential direction, several oil outlets 22 are formed on the two axial end faces of the stator core 2, and the cooling medium is directly sprayed onto the two ends of the stator winding to achieve direct cooling of the stator winding ends 3.

[0062] The cooling structure for the stator core 2 provided by this utility model has the following advantages compared with the prior art:

[0063] (1) Simple structure: Compared with the traditional oil-cooled motor which uses an oil spray ring or oil spray pipe to spray cooling oil onto the stator winding, this application directly sets an oil guide channel on the stator core 2, and directly sets an oil inlet 241 and an oil outlet 22 on the stator core 2. The cooling of the stator winding does not need to rely on an oil spray ring or oil spray pipe, nor does it require additional fixed brackets and seals. The simple structure greatly reduces the number of parts and reduces manufacturing and maintenance costs. The simple structure also simplifies the assembly process and can avoid the problem of seal failure or oil leakage caused by process assembly errors.

[0064] This stator core 2, with fewer components and a simpler structure, is compact, occupies less space, and is also conducive to the lightweighting and overall layout of the vehicle.

[0065] (2) Uniform cooling: Compared with the uneven cooling method where the oil path of the oil injection ring or oil injection pipe cannot fully cover the stator winding end 3, this application sets up a U-shaped oil guide channel 21 back to back on the stator core 2. There are two oil outlets 22 in the axial area of ​​the stator winding end 3. That is, the cooling medium sprayed by the two oil outlets 22 with different positions on the same diameter will cover different areas, so as to completely cover the axial area of ​​the stator winding end 3, improve the uniformity of cooling and heat dissipation of the stator winding end 3, avoid the local temperature rise of the stator winding end 3 being too high, and the thermal stress concentration caused by the temperature gradient difference, which accelerates the insulation aging and reduces the service life of the motor. It also avoids the problem of local overheating triggering the safety protection mechanism when the motor is running at high power, thus limiting the performance of the motor.

[0066] Currently, setting a straight oil guide channel on the stator core 2 can solve the problem of complex traditional structures. However, this cooling method only has one oil outlet 22 at each end of the stator core 2. In this application, a U-shaped oil guide channel 21 is set back to back on the stator core 2, and four oil outlets 22 are set at both ends of the stator core 2. The stator winding end 3 at the same end has two corresponding oil outlets 22 along the axial region, which also greatly improves the heat dissipation and cooling effect of the stator winding.

[0067] (3) Reduced flow resistance and energy consumption: The U-shaped oil guide channels 21 back to back are provided on the stator core 2 in this application. Each U-shaped oil guide channel 21 is provided with an oil inlet 241 and two oil outlets 22. Therefore, the flow time of the cooling medium on the U-shaped oil guide channel 21 is shortened, the flow resistance of the cooling medium is reduced, and the flow speed of the cooling medium is increased, thereby improving the cooling and heat dissipation effect. The smooth flow of the cooling medium avoids the energy consumption caused by the pump pressure needing to overcome the flow resistance, thereby reducing energy consumption and also benefiting the improvement of motor power.

[0068] In this application, the cooling medium enters the corresponding U-shaped oil guide channel 21 from different iron core oil inlets 241, and then is directly sprayed onto the stator winding end 3 through the oil outlet 22. Combined with the oil outlets 22 distributed along the circumferential direction, the sprayed cooling medium can completely cover the stator winding end 3, improving the uniformity of cooling of the stator winding end 3.

[0069] In some embodiments, see Figure 4The stator core 2 includes a first core group 23, a second core group 24, a third core group 25, a fourth core group 26 arranged along the vertical bisector of its axial length, and a fifth core group 27 located on the vertical bisector; a U-shaped oil guide channel 21 is symmetrically arranged along the vertical bisector; the fifth core group 27 isolates the symmetrically arranged U-shaped oil guide channel 21; the U-shaped oil guide channel 21 extends axially to the first core group 23 to form an oil outlet 22; the core oil inlet 241 can be selectively arranged on the first core group 23, the second core group 24, the third core group 25, or the fourth core group 26.

[0070] In the above technical solution, the stator core 2 itself is composed of several core laminations stacked together. In this application, the stator core 2 is distinguished according to the different positions of the internal oil guiding channels, and symmetrically arranged U-shaped oil guiding channels are set on the symmetrical stator core 2. Each U-shaped oil guiding channel 21 is provided with an oil inlet 241. The distance and flow rate of the cooling medium reaching the stator winding end 3 on the U-shaped oil guiding channel 21 are the same, so that the flow rate of the sprayed cooling medium received by the stator winding end 3 at both ends of the axial direction of the stator core 2 is the same, thereby ensuring the consistency of cooling and heat dissipation of the stator winding end 3 at both ends and avoiding the influence of local temperature difference, local overheating and other factors.

[0071] The axial length referred to in this application is the axial length of the stator core 2. The first core group 23, the second core group 24, the third core group 25, and the fourth core group 26 are symmetrically arranged with the perpendicular bisector of the axial length as the axis of symmetry.

[0072] In this application, the first core group 23, the second core group 24, the third core group 25, the fourth core group 26 and the fifth core group 27 are stacked together and arranged symmetrically. The fifth core group 27 is located on the axis of symmetry, and the first core group 23 is farthest from the axis of symmetry, located at both ends of the stator core 2.

[0073] The oil inlet 241 can be located on the first core group 23, or on the second core group 24, the third core group 25, or the fourth core group 26, and is connected to the U-shaped oil guide channel 21. Preferably, the oil inlet 241 is arranged radially and located on the outer edge of each core group.

[0074] Because the stator core 2 is coaxially mounted inside the housing 1, the interference fit between the stator core 2 and the housing 1 creates a seal, preventing the risk of cooling medium leakage between the housing 1 and the stator core 2. Of course, the housing 1 is equipped with oil inlet channels 11 that communicate with each U-shaped oil guide channel. The branch oil channels 12 of the oil inlet channels 11 are respectively connected to the oil inlet ports 241 of the core, and the housing is equipped with a main oil inlet 13.

[0075] It should be noted that, based on the concept of a U-shaped oil guide channel 21 having two oil outlets 22 in this application, the U-shaped oil guide channel 21 may optionally be asymmetrically arranged.

[0076] In some embodiments, see Figure 8 The first core assembly 23 includes a first core lamination 233. First oil guide holes 231 are evenly distributed on a first pitch circle near the outer edge of the first core lamination 233, and second oil guide holes 232 are evenly distributed on a second pitch circle near the teeth of the first core lamination 233. The first oil guide holes 231 and second oil guide holes 232 correspond one-to-one. The first oil guide holes 231 and second oil guide holes 232 form an oil outlet 22 and constitute part of a U-shaped oil channel 21. The first oil guide holes 231 are located on the periphery of the first core lamination 233, serving to prevent the cooling medium from stagnating and forming a dead zone.

[0077] For ease of description later, the diameter of the first pitch circle is defined as D1, and the diameter of the second pitch circle is defined as D2. See [link to relevant documentation]. Figure 4 .

[0078] In this application, the second oil guide hole 232 is disposed between two adjacent teeth on the first iron core lamination 233. The shape and size of the first oil guide hole 231 and the second oil guide hole 232 may be the same or different; in this application, the first oil guide hole 231 and the second oil guide hole 232 adopt the same size and the shape is rectangular.

[0079] As mentioned earlier, the stator core 2 is made of several core laminations. The oil guide holes are made using a separate stamping mold. The first oil guide hole 231 and the second oil guide hole 232 can be punched out at once on the first core lamination 233.

[0080] In this application, the first iron core group 23 may include only one first iron core lamination 233, or it may include multiple first iron core laminations 233. Each of the multiple first iron core laminations 233 has a first oil guide hole 231 and a second oil guide hole 232 punched out. They are stacked together, and the multiple second oil guide holes 232 are connected and the multiple first oil guide holes 231 are connected, forming part of the U-shaped oil guide channel 21.

[0081] In some embodiments, see Figure 9 The second core assembly 24 includes a second core lamination 243. The outer diameter of the second core lamination 243 is smaller than the outer diameter of the first core lamination 233, and forms an oil inlet 241. Third oil guide holes 242 are evenly distributed on the third pitch circle near the teeth of the second core lamination 243. The third oil guide holes 242 are connected to the second oil guide holes 232 in a one-to-one correspondence, and form part of the U-shaped oil guide channel 21.

[0082] In the above technical solution, the outer diameter of the second core group 24 is smaller than that of the first core lamination 233 and other core laminations. The second core group 24 is stacked between the first core group 23 and the third core group 25. Due to the small outer diameter, an annular notch is formed, which directly serves as the core oil inlet 241. It can be seen that the core oil inlet 241 does not need to be set up separately.

[0083] Specifically, the outer diameter of the second core lamination 243 is consistent with the minimum distance from the first oil guide hole 231 to the axis of the stator core 2, to ensure that the cooling medium can smoothly enter the first oil guide hole 231. The outer diameter of the second core lamination 243 is denoted as D1-r1, where r1 is the radius of the first oil guide hole 231. The diameter of the third pitch circle is consistent with that of the second pitch circle, denoted as D3, where D3 = D2.

[0084] The third oil guide hole 242 is punched out in one go using a separate stamping die on the third iron core lamination 256. The shape and size of the third oil guide hole 242 are the same as those of the second oil guide hole 232.

[0085] In some embodiments, see Figure 4 and Figure 11 The third core assembly 25 includes a third core lamination 256. Fourth oil guide holes 251 are evenly distributed on the fourth pitch circle near the outer edge of the third core lamination 256. The fourth oil guide holes 251 and the core oil inlet 241 overlap axially to form a connection, and the fourth oil guide holes 251 are offset towards the center of the stator core 2. Fifth oil guide holes 255 are evenly distributed on the fifth pitch circle near the teeth of the third core lamination 256. The fifth oil guide holes 255 and the third oil guide holes 242 overlap axially to form a connection, and the fifth oil guide holes 255 are offset away from the center of the stator core 2. The fourth oil guide holes 251 and the fifth oil guide holes 255 constitute the bottom variable cross-section portion of the U-shaped oil guide channel 21.

[0086] In the above technical solution, the bottom variable cross-section of the U-shaped oil guide channel 21 formed on the third iron core group 25 allows the cooling medium to pass smoothly at the bend, avoiding the generation of flow resistance which would reduce the flow speed of the cooling medium, increase the energy consumption of the pump supplying the cooling medium, and increase the energy consumption of the motor.

[0087] The diameter of the fourth pitch circle is D4, where D4 < D1; the diameter of the fifth pitch circle is D5, where D5 > D3. (See also...) Figure 4 .

[0088] In some embodiments, see Figure 4 and Figure 11The third core group 25 includes a plurality of third core laminations 256; the fourth oil guide holes 251 on adjacent third core laminations 256 are arranged radially offset, and the fifth oil guide holes 255 on adjacent third core laminations 256 are arranged radially offset, and the radial distance between the fourth oil guide hole 251 and the corresponding fifth oil guide hole 255 gradually decreases towards the fifth core group 27, forming a stepped shape to constitute the bottom variable cross-section portion of the U-shaped oil guide channel 21.

[0089] In the above technical solution, when the third core group 25 includes multiple third core laminations 256, since each oil guide hole on the third core lamination 256 is punched out in one go by a mold, and the center line of each oil guide hole is parallel to the axis of the stator core 2, the distance between the fourth oil guide hole 251 and the fifth oil guide hole 255 on each third core lamination 256 is inconsistent. That is, in order to ensure the connection of adjacent fourth oil guide holes 251, the radial distance between the fourth oil guide hole 251 and the fifth oil guide hole 255 must be gradually reduced to form a bottom variable cross section. Therefore, the multiple fourth oil guide holes 251 formed by the multiple third core laminations 256 after stacking are in the form of stepped channels, and the multiple fifth oil guide holes 255 are also in the form of steps.

[0090] Because the positions of the fourth oil guide hole 251 and the fifth oil guide hole 255 on the third iron core lamination 256 change, the diameter of the pitch circle also changes continuously. However, this paper uses D4 to represent it, so D4 here is a variable.

[0091] Optionally, see Figure 4 and Figure 10 The third core assembly 25 also includes a third connecting core lamination 254, which is stacked between the second core lamination 243 and the third core lamination 256. A sixth oil guide hole 252 is uniformly arranged on the sixth pitch circle near its edge of the third connecting core lamination 254, and a seventh oil guide hole 253 is uniformly arranged on the seventh pitch circle near its teeth. The minimum radius of the sixth oil guide hole 252 to the axis of the stator core 2 is consistent with the minimum radius of the first oil guide hole 231 to the axis of the stator core 2, thus allowing axial flow from the core oil inlet 241 to the sixth oil guide hole 252, avoiding flow resistance of the cooling medium. Similarly, the minimum radius of the seventh oil guide hole 253 is consistent with that of the third oil guide hole 242.

[0092] The third connecting iron core lamination 254 can be one or multiple laminations.

[0093] The sixth oil guide hole 252 and the seventh oil guide hole 253 are also formed by punching in one go using a separate stamping die.

[0094] Based on the above technical features, when the stator core uses all third core laminations 256, the multiple fourth oil guide holes 251 form stepped channels, and the U-shaped oil guide channel 21 is stepped; when the stator core uses all third connecting core laminations 254 or first core laminations 233, the U-shaped oil guide channel 21 is straight; when as in this application... Figure 1 As shown, when the third connecting iron core lamination 254 or the first iron core lamination 233 is partially adopted, and the third iron core lamination 256 is partially adopted, the opening of the U-shaped oil guiding channel 21 is straight and the bottom is stepped.

[0095] In some embodiments, see Figure 4 and Figure 5 The diameter of the fourth oil guide hole 251 is the same as that of the fifth oil guide hole 255, and is larger than that of the first oil guide hole 231. By enlarging the oil guide holes, the flow resistance of the cooling medium is reduced, especially at bends, thereby reducing energy consumption and improving heat dissipation.

[0096] In this application, the diameter of the sixth pitch circle is D6 (not marked in the figure, see D3), D6 > D1, and the diameter of the seventh pitch circle is D7 (not marked in the figure, see D4), D7 is less than D3 because the dimensions of the sixth oil guide hole 252 and the seventh oil guide hole 253 are the same as the dimensions of the fourth oil guide hole 251, and are both larger than the third oil guide hole 242 and the first oil guide hole 231.

[0097] In some embodiments, see Figure 4 and Figure 12 The fourth core assembly 26 includes a fourth core lamination 262, on which a connecting hole 261 is provided, connecting the fourth oil guide hole 251 and the fifth oil guide hole 255. The elongated hole on the fourth core lamination 262, connecting the fourth oil guide hole 251 and the fifth oil guide hole 255, allows the cooling medium to flow from one core oil inlet 241 to two oil outlets 22.

[0098] Optionally, the fourth core group 26 can be formed by stacking multiple fourth core laminations 262.

[0099] See Figure 4 and Figure 13 The fifth core group 27 isolates the two U-shaped oil guide channels 21. The fifth core group 27 includes one or two fifth core laminations 271, and no oil guide holes are provided on the fifth core laminations 271.

[0100] This application therefore includes a first iron core lamination 233, a second iron core lamination 243, a third iron core lamination 256, a fourth iron core lamination 262 and a fifth iron core lamination 271. After the laminations are stacked in sequence, the oil guide holes are connected in sequence to form a U-shaped oil guide channel 21.

[0101] Based on the same utility model concept, this application embodiment also provides an oil-cooled motor, including a stator core 2 and a housing 1 coaxially mounted outside the stator core 2. An oil inlet channel 11 connected to a U-shaped oil guide channel 21 is provided on the housing 1, and the branch oil channels 12 of the oil inlet channel 11 are respectively connected to the oil inlet 241 of the stator core.

[0102] This application provides an oil-cooled motor that, through a U-shaped oil guide channel 21 directly disposed inside the stator core 2, can not only directly cool the stator core 2 and the stator winding ends 3, but also eliminates the need for redundant oil spraying and sealing structure designs. Therefore, the oil-cooled motor provided by this application has fewer redundant structures, a compact structure, a small size, and occupies less space. It can also significantly reduce manufacturing and maintenance costs, and is also beneficial to the overall layout and lightweight design of new energy vehicles.

[0103] The U-shaped oil guide channel 21 can ensure that the cooling medium is evenly distributed in the oil-cooled motor, avoid local overheating, improve the reliability of the oil-cooled motor operation, and significantly improve the motor's heat dissipation performance and operating stability.

[0104] Thirdly, this utility model embodiment also provides a vehicle including the cooling structure of the stator core 2.

[0105] The vehicle provided by this utility model, by utilizing the cooling structure of this stator core 2, can improve the uniformity of cooling of the oil-cooled motor, significantly improve the heat dissipation performance and operational stability of the motor, thereby reducing the failure rate of the whole vehicle, improving the operational stability of the whole vehicle, and also significantly reducing manufacturing and maintenance costs. It is also beneficial to the overall layout and lightweight design of new energy vehicles.

[0106] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A cooling structure for a stator core, characterized in that, The stator core (2) has a U-shaped oil guide channel (21) arranged back to back inside, and the two oil outlets (22) of the U-shaped oil guide channel (21) are both facing the stator winding end (3); The stator core (2) is provided with an oil inlet (241) that connects to the U-shaped oil guide channel (21); The cooling medium entering the U-shaped oil channel (21) is directly sprayed onto the stator winding end (3) through the oil outlet (22).

2. The cooling structure for a stator core according to claim 1, characterized by The stator core (2) includes a first core group (23), a second core group (24), a third core group (25), a fourth core group (26) and a fifth core group (27) located on the vertical bisector along the axial length. The U-shaped oil guide channel (21) is arranged along the vertical bisector; the fifth iron core group (27) isolates the symmetrically arranged U-shaped oil guide channel (21); The U-shaped oil guide channel (21) extends axially to the first iron core assembly (23) to form the oil outlet (22); The oil inlet (241) of the iron core can be optionally located on the first iron core group (23), the second iron core group (24), the third iron core group (25) or the fourth iron core group (26).

3. The cooling structure for a stator core according to Claim 2, wherein The first core assembly (23) includes a first core lamination (233). A first oil guide hole (231) is evenly distributed on a first pitch circle near its outer edge of the first core lamination (233). A second oil guide hole (232) is evenly distributed on a second pitch circle near its teeth of the first core lamination (233). The first oil guide hole (231) and the second oil guide hole (232) correspond one-to-one. The first oil guide hole (231) and the second oil guide hole (232) constitute the oil outlet (22) and form part of the U-shaped oil guide channel (21).

4. The cooling structure for a stator core according to claim 3, characterized in that, The second core assembly (24) includes a second core lamination (243), the outer diameter of which is smaller than that of the first core lamination (233), and forms the core oil inlet (241); the second core lamination (243) has a third oil guide hole (242) evenly distributed on the third pitch circle near its teeth, the third oil guide hole (242) and the second oil guide hole (232) are connected in a one-to-one correspondence, and form part of the U-shaped oil guide channel (21).

5. The cooling structure for a stator core according to Claim 4, wherein The third core assembly (25) includes a third core lamination (256). A fourth oil guide hole (251) is evenly distributed on the fourth pitch circle near its outer edge of the third core lamination (256). The fourth oil guide hole (251) overlaps with the core oil inlet (241) in the axial direction to form a connection, and the fourth oil guide hole (251) is offset towards the center of the stator core (2). The fifth oil guide hole (255) is evenly distributed on the fifth pitch circle near the teeth of the third iron core lamination (256). The fifth oil guide hole (255) and the third oil guide hole (242) partially overlap along the axial direction to form a connection, and the fifth oil guide hole (255) is offset away from the center of the stator iron core (2). The fourth oil guide hole (251) and the fifth oil guide hole (255) constitute the bottom variable cross-section portion of the U-shaped oil guide channel (21).

6. The cooling structure for a stator core according to claim 5, characterized by The third core group (25) includes a plurality of third core laminations (256); the fourth oil guide holes (251) on adjacent third core laminations (256) are arranged radially offset, the fifth oil guide holes (255) on adjacent third core laminations (256) are arranged radially offset, and the radial distance between the fourth oil guide hole (251) and the corresponding fifth oil guide hole (255) gradually decreases towards the fifth core group (27), forming the bottom variable cross section.

7. The cooling structure for the stator core as described in claim 5, characterized in that, The diameter of the fourth oil guide hole (251) is the same as that of the fifth oil guide hole (255), and is larger than that of the first oil guide hole (231).

8. The cooling structure for a stator core according to claim 5, characterized by The fourth core assembly (26) includes a fourth core lamination (262), and the fourth core lamination (262) is provided with a connecting hole (261) that connects the fourth oil guide hole (251) and the fifth oil guide hole (255).

9. Oil-cooled electric machine, characterized in that The cooling structure includes the stator core as described in any one of claims 1-8.

10. Vehicle, characterized in that The cooling structure includes the stator core as described in any one of claims 1-8.

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