Oil-cooled motor
By designing a multi-channel cooling system that runs through the axially in the motor stator core, the high temperature problem of new energy vehicle drive motors during high-speed operation is solved, and a more efficient and uniform heat dissipation effect is achieved.
Patent Information
- Application Number
- CN202411836484.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2022-05-10
- Publication Date
- 2025-04-01
AI Technical Summary
When the new energy vehicle drive motor is running at high speed, the heat of the rotor parts increases sharply. If the heat cannot be effectively dissipated, it will affect the performance and reliability of the motor.
A motor stator is designed, including a hollow columnar stator core, and is equipped with first and second oil cooling channels that penetrate in the axial direction, through which cooling oil is transported from both ends of the stator core to the interior to achieve multi-oil cooling.
Through multi-channel cooling with opposite flow directions, the heat dissipation efficiency of the motor stator is improved, uniform heat dissipation is achieved, and the radial size of the stator core is reduced.
Smart Images
Figure CN119742949A_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the technical field of motor cooling, and in particular to an oil-cooled motor. Background Art
[0002] Taking the drive motor of new energy vehicles as an example, the higher the motor speed, torque density and power density, the higher the heat it generates. Therefore, the heat dissipation and cooling structure of the motor are essential for the reliable, stable and efficient operation of the motor. The cooling of the motor can be divided into air cooling, water cooling and oil cooling. Oil cooling is becoming the first choice for high-performance motor cooling solutions due to its natural electrical insulation and high degree of freedom in structural design.
[0003] The driving motors of new energy vehicles are mostly permanent magnet synchronous motors. When the motors are running in the medium and low speed range, the motor stator parts generate a lot of heat, of which the main heat is generated by the stator winding and the stator core; when the motors are running in the high speed range, the heat of the motor rotor parts increases sharply. Therefore, if the stator parts or rotor parts of the driving motor cannot be effectively cooled, it will directly affect the overall performance of the motor, resulting in low reliability, stability and efficiency of the motor operation, which will seriously affect the reliable and stable operation of the vehicle. Summary of the invention
[0004] The present application provides an improved motor stator and an oil-cooled motor, which can improve the cooling effect and enhance the compactness of the motor stator.
[0005] The present application provides a motor stator, comprising a stator core in a hollow columnar structure, the stator core comprising a first end and a second end in an axial direction, the stator core being provided with a first oil cooling channel and a second oil cooling channel extending along the axial direction, the first oil cooling channel forming a first oil inlet at the first end and a first oil outlet at the second end, the second oil cooling channel forming a second oil outlet at the first end and the second oil inlet at the second end, at the first end, the first oil inlet and the second oil outlet are arranged along the circumferential direction of the stator core and are located on the same circumference with the axis of the stator core as the center.
[0006] Optionally, the stator core includes a plurality of lamination groups stacked along the axial direction, each of the lamination groups is provided with a first oil hole extending along the axial direction, the first oil holes are connected in sequence to form the first oil cooling channel, and in at least two adjacent lamination groups, the flow area of the first oil hole of the lamination group close to the first oil inlet is larger than the connecting area of the two first oil holes of the two adjacent lamination groups.
[0007] Optionally, in two adjacent lamination groups, the flow area of the first oil hole of the lamination group close to the first oil inlet is larger than the flow area of the first oil hole of the other lamination group; or
[0008] The flow areas of the first oil holes of two adjacent lamination groups are equal, and the first oil holes of two adjacent lamination groups are staggered in the circumferential direction and partially connected.
[0009] Optionally, the stator core includes a plurality of lamination groups stacked along the axial direction, each of the lamination groups is provided with an axially extending second oil hole, the second oil holes are connected in sequence to form the second oil cooling channel, and in at least two adjacent lamination groups, the flow area of the second oil hole of the lamination group close to the second oil inlet is larger than the connecting area of the two second oil holes of the two adjacent lamination groups.
[0010] Optionally, the first oil inlet and the first oil outlet are opposite to each other along the axial direction of the stator core, or are staggered along the circumferential direction of the stator core; and / or
[0011] The second oil inlet and the second oil outlet are opposite to each other along the axial direction of the stator core, or are staggered along the circumferential direction of the stator core; and / or
[0012] At the second end, the second oil inlet and the first oil outlet are arranged along the circumferential direction of the stator core and are located on the same circumference with the axis of the stator core as the center.
[0013] Optionally, the first oil cooling channel is provided in plurality, and the second oil cooling channel is provided in plurality;
[0014] At the first end, the plurality of first oil inlets are arranged along the circumference of the stator core, the plurality of second oil outlets are arranged along the circumference of the stator core, and the plurality of first oil inlets and the plurality of second oil outlets are arranged alternately; and / or
[0015] At the second end, the plurality of second oil inlets are arranged along the circumferential direction of the stator core, the plurality of first oil outlets are arranged along the circumferential direction of the stator core, and the plurality of second oil inlets and the plurality of first oil outlets are arranged alternately.
[0016] Optionally, the motor stator also includes a first oil ring arranged at the first end of the stator core, the first oil ring is coaxial with the stator core, the first oil ring is provided with a first oil inlet cavity connected to the first oil inlet, and a first oil outlet cavity connected to the second oil outlet.
[0017] Optionally, the outer surface of the first oil ring is formed with a first groove and a first boss which are arranged circumferentially and extend axially, the first groove forms the first oil inlet cavity, and the first boss is provided with the first oil outlet cavity on one end surface facing the stator core, and the first oil outlet cavity extends axially.
[0018] Optionally, a first oil injection hole is formed on the inner surface of the first oil ring, the first oil injection hole is communicated with the first oil outlet cavity, the stator includes a stator winding, and the first oil injection hole is opposite to the stator winding.
[0019] Optionally, the motor stator also includes a second oil ring arranged at the second end of the stator core, the second oil ring is coaxial with the stator core, and the second oil ring includes a second oil inlet chamber connected to the second oil inlet, and a second oil outlet chamber connected to the first oil outlet.
[0020] Optionally, the outer surface of the second oil ring is formed with circumferentially distributed second grooves and axially extending second bosses, the second grooves are formed as the second oil inlet chamber, and the second boss is provided with the second oil outlet chamber on one end surface facing the stator core, and the second oil outlet chamber extends axially.
[0021] Optionally, a second oil injection hole is formed on the inner surface of the second oil ring, the second oil injection hole is communicated with the second oil outlet cavity, the stator includes a stator winding, and the second oil injection hole is opposite to the stator winding.
[0022] The present application also provides an oil-cooled motor, comprising:
[0023] A housing, wherein the housing is provided with a housing oil inlet;
[0024] As described in any one of the above items, the motor stator is arranged in a housing, and includes a stator core, and the first oil inlet and the second oil inlet of the stator core are both connected to the oil inlet of the housing.
[0025] The technical solution provided by this application can at least achieve the following beneficial effects:
[0026] The present application provides a motor stator and an oil-cooled motor, wherein the stator core is provided with a first oil-cooling channel and a second oil-cooling channel with opposite flow directions, thereby cooling oil can be transported to the stator core from both ends of the stator core axial direction through the first oil-cooling channel and the second oil-cooling channel, respectively, so that the stator core can be cooled through multiple oil channels with opposite flow directions, thereby improving the heat dissipation efficiency and achieving uniform heat dissipation. In addition, the first oil inlet and the second oil outlet are arranged along the circumference of the stator core and are located on the same circumference with the axis of the stator core as the center. Such a layout can not only cool the stator core at different positions in the circumferential direction, but also make the first oil inlet and the second oil outlet more compact in the radial direction of the stator core, which is conducive to reducing the radial size of the stator core. BRIEF DESCRIPTION OF THE DRAWINGS
[0027] Figure 1 is a cross-sectional view of a partial structure of an oil-cooled motor shown in an exemplary embodiment of the present application;
[0028] Figure 2 is a schematic diagram of a stator core shown in an exemplary embodiment of the present application;
[0029] Figure 3 is a schematic diagram of a first cooling oil channel and a second cooling oil channel of a stator core shown in an exemplary embodiment of the present application;
[0030] Figure 4 is a schematic diagram showing that the first oil holes of each lamination group of the stator core are connected;
[0031] Figure 5 is a schematic diagram of a first oil ring shown in an exemplary embodiment of the present application;
[0032] Figure 6 It is a schematic diagram of a first oil ring and a second oil ring assembled at both ends of a stator core;
[0033] Figure 7 yes Figure 6 Schematic diagram of part of the structure shown in . DETAILED DESCRIPTION
[0034] Here, exemplary embodiments will be described in detail, and examples thereof are shown in the accompanying drawings. When the following description refers to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present application. Instead, they are only examples of devices and methods consistent with some aspects of the present application.
[0035] The terms used in this application are only for the purpose of describing specific embodiments, and are not intended to limit this application. Unless otherwise defined, the technical terms or scientific terms used in this application should be understood by people with ordinary skills in the field to which this application belongs. The "first", "second" and similar words used in this application do not indicate any order, quantity or importance, but are only used to distinguish different components. Similarly, similar words such as "one" or "one" do not indicate quantity restrictions, but indicate that there is at least one, and will be separately described if only "one" is referred to. "Multiple" or "several" means two or more. Unless otherwise specified, similar words such as "front", "rear", "lower" and / or "upper", "top", "bottom" are only for the convenience of explanation, and are not limited to one position or one spatial orientation. Similar words such as "include" or "comprise" mean that the elements or objects appearing in front of "include" or "comprise" cover the elements or objects listed after "include" or "comprise" and their equivalents, and do not exclude other elements or objects. The words "connected" or "connected" and the like are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect.
[0036] Please refer to Figure 1 , Figure 1 It is a schematic diagram showing a partial structure of an oil-cooled motor 1 according to an exemplary embodiment of the present application.
[0037] The oil-cooled motor 1 provided in the embodiment of the present application includes a housing 10, a stator 20 and a rotor (not shown). The housing 10 is provided with a receiving chamber 101, the stator 20 and the rotor are both received in the receiving chamber 101, and the stator 20 is coaxially arranged with the rotor. The stator 20 and the housing 10 are relatively fixed, the rotor 30 is rotatable relative to the stator 20, and the stator 20 is arranged around the outside of the rotor. The housing 10 is also provided with a housing oil inlet 102, through which cooling oil can be input into the stator core 21.
[0038] The stator 20 includes a stator core 21 and a stator winding 22 assembled on the stator core 21. The stator core 21 is a hollow columnar structure, and the rotor is assembled in the hollow of the stator core 21. The oil-cooled motor 1 can cool the stator core 21 and the stator winding 22 by oil.
[0039] Please refer to Figure 2 , Figure 2 This is a schematic diagram of a stator core 21 according to an exemplary embodiment of the present application.
[0040] The stator core 21 is a hollow cylindrical structure having an axis O. The axial direction of the stator core 21 refers to the extension direction of the axis O, and the circumferential direction of the stator core 21 refers to the circumferential direction around the axis O.
[0041] The stator core 21 includes a first oil cooling channel 210, a second oil cooling channel 211, and a first end 212 and a second end 213 in the axial direction. The first oil cooling channel 210 runs through the first end 212 and the second end 213, a first oil inlet 2100 is formed at the first end 212, and a first oil outlet 2102 is formed at the second end 213. The first oil inlet 2100 is for oil to enter, and the first oil outlet 2102 is for oil to flow out. The second oil cooling channel 211 runs through the first end 212 and the second end 213, a second oil inlet 2110 is formed at the second end 213, and a second oil outlet 2112 is formed at the first end 212. The second oil inlet 2110 is for oil to enter, and the second oil outlet 2112 is for oil to flow out. With such an arrangement, cooling oil can be transported to the stator core 21 from both axial ends of the stator core 21 through the first oil cooling channel 210 and the second oil cooling channel 211 respectively, so that the stator core 21 can be cooled through multiple oil channels with opposite flow directions, thereby improving the heat dissipation efficiency and achieving uniform heat dissipation.
[0042] The present application also proposes that, at the first end 212, the first oil inlet 2100 and the second oil outlet 2112 are arranged along the circumference of the stator core 21, and are located on the same circumference with the axis of the stator core 21 as the center. The first oil inlet 2100 and the second oil outlet 2112 are distributed circumferentially, so that the stator core 21 can be cooled at different positions in the circumferential direction. Moreover, such a layout can also make the first oil inlet 2100 and the second oil outlet 2112 more compact in the radial direction of the stator core 21, which is conducive to reducing the radial size of the stator core 21 at the first end 212.
[0043] Similarly, at the second end 213, the first oil outlet 2102 and the second oil inlet 2110 may be arranged along the circumference of the stator core 21 and located on the same circumference with the axis of the stator core 21 as the center. This is conducive to reducing the radial dimension of the stator core 21 at the second end 213.
[0044] In one embodiment, the stator core 21 is provided with a plurality of first oil cooling channels 210 extending in parallel, and accordingly, the plurality of first oil cooling channels 210 form a plurality of first oil inlets 2100 at the first end 212, and a plurality of first oil outlets 2102 at the second end 213, and the plurality of first oil inlets 2100 are connected to the plurality of first oil outlets 2102 in a one-to-one correspondence. In this way, the cooling area of the stator core 21 can be increased, the cooling effect can be further improved, and the uniformity of heat dissipation of the motor stator 20 can be further improved.
[0045] The stator core 21 can also be provided with a plurality of second oil cooling channels 211 extending in parallel, the plurality of second oil cooling channels 211 forming a plurality of second oil inlets 2110 at the second end 213, and a plurality of second oil outlets 2112 at the first end 212, the plurality of second oil inlets 2110 being connected to the plurality of second oil outlets 2112 in a one-to-one correspondence.
[0046] In one embodiment, at the first end 212, a plurality of the first oil inlets 2100 are arranged circumferentially, a plurality of the second oil outlets 2112 are arranged circumferentially, and the plurality of the first oil inlets 2100 and the plurality of the second oil outlets 2112 are arranged interlaced. The "interlaced" mentioned here means that the plurality of the first oil inlets 2100 and the plurality of the second oil outlets 2112 are arranged in a mixed manner in the circumferential direction, so that the plurality of the first oil inlets 2100 and the plurality of the second oil outlets 2112 can be dispersed from each other, avoiding excessive concentration of the plurality of the first oil inlets 2100 and the plurality of the second oil outlets 2112. For example, as an embodiment of the interlaced arrangement, one or more second oil outlets 2112 are arranged between two adjacent first oil inlets 2100; or, one or more first oil inlets 2100 are arranged between two adjacent second oil outlets 2112. As another embodiment of the interlaced arrangement, the first oil inlets 2100 and the second oil outlets 2112 are arranged alternately. The advantage of such an interlaced arrangement is that it can achieve uniform cooling at various circumferential positions of the stator core 21, and reduce the temperature difference at different positions of the stator core 21. Specifically, during the flow of the cooling oil, the cooling oil and the stator core 21 will continuously exchange heat. At the first oil inlet 2100, the temperature of the cooling oil is relatively low, and the heat exchange effect with the stator core 21 is good. At the second oil outlet 2112, the temperature of the cooling oil is relatively high, and the heat exchange effect with the stator core 21 becomes poor. By interlacing the first oil inlet 2100 and the second oil outlet 2112, the temperature difference at various circumferential positions of the stator core 21 at the first end 212 can be reduced, so that the stator core 21 can achieve uniform heat dissipation at the first end 212.
[0047] In one embodiment, at the second end 213, a plurality of the second oil inlets 2110 are arranged circumferentially, a plurality of the first oil outlets 2102 are arranged circumferentially, and the plurality of the second oil inlets 2110 are arranged interlaced with the plurality of the first oil outlets 2102. In this way, the temperature difference at each circumferential position of the second end 213 is relatively small, so that the stator core 21 can achieve uniform heat dissipation at the second end 213.
[0048] In one embodiment, a plurality of first oil cooling channels 210 and a plurality of second oil cooling channels 211 can be distributed along the circumference of the stator core 21 over the entire circumference of the stator core 21. Accordingly, a plurality of first oil inlets 2100 and a plurality of second oil outlets 2112 formed at the first end 212 and a plurality of second oil inlets 2110 and a plurality of first oil outlets 2102 formed at the second end 213 are all distributed along the circumference over the entire circumference of the stator core. In this way, 360° omnidirectional heat dissipation of the stator core 21 can be achieved in the circumferential direction. Among them, the plurality of first oil inlets 2100 and the plurality of second oil outlets 2112 are located on the same circumference with the axis of the stator core 21 as the center, and the plurality of second oil inlets 2110 and the plurality of first oil outlets 2102 are located on the same circumference with the axis of the stator core 21 as the center.
[0049] exist Figure 2 In the illustrated embodiment, the first oil inlet 2100 and the first oil outlet 2102 of the first cooling oil channel 210 are arranged opposite to each other along the axial direction of the stator core 21, so that the first oil cooling channel 210 can be formed as an oil cooling channel with a straight-through structure, so that the cooling part of the stator core 21 can be relatively concentrated in the circumferential direction.
[0050] exist Figure 2 In the illustrated embodiment, the second oil inlet 2110 and the second oil outlet 2112 of the second cooling oil channel 211 are arranged opposite to each other along the axial direction of the stator core 21, so that the second cooling oil channel 211 can be formed as an oil cooling channel with a straight-through structure, so that the cooling part of the stator core 21 can be relatively concentrated in the circumferential direction.
[0051] Please refer to Figure 3 , Figure 3 FIG. 2 is a schematic diagram of another embodiment of the first cooling oil passage 210 and the second cooling oil passage 211 in the stator core 21 .
[0052] exist Figure 3 In the illustrated embodiment, the first oil inlet 2100 and the first oil outlet 2102 of the first cooling oil channel 210 are staggered along the circumference of the stator core 21, so that the first oil cooling channel 210 can be formed as an oil cooling channel with a spiral structure, which makes the cooling part of the stator core 21 relatively dispersed in the circumferential direction.
[0053] exist Figure 3 In the illustrated embodiment, the second oil inlet 2110 and the second oil outlet 2112 of the second cooling oil channel 211 are staggered along the circumference of the stator core 21, so that the second oil cooling channel 211 can be formed as a spirally structured oil cooling channel, which makes the cooling part of the stator core 21 relatively dispersed in the circumferential direction.
[0054] The present application has no restrictions on the shape and size of the first oil inlet 2100 and the first oil outlet 2102. In the present embodiment, the first oil inlet 2100 and the first oil outlet 2102 are both configured as square openings, and the opening area of the first oil inlet 2100 is equal to the opening area of the first oil outlet 2102. In other embodiments, the first oil inlet 2100 and the first oil outlet 2102 may both be configured as circular openings, and the diameter of the first oil inlet 2100 may be equal to or different from the diameter of the first oil outlet 2102.
[0055] Please continue to refer to Figure 2 The stator core 21 includes a plurality of lamination groups 214 stacked along the axial direction. Each lamination group 214 is formed by stacking a plurality of laminations along the thickness direction. The plurality of laminations can be reliably connected by welding, riveting or bonding. The number of laminations in each lamination group 214 is not limited and can be selected and set according to actual needs. Each lamination in the same lamination group 214 can be set to be the same lamination.
[0056] Each of the lamination stacks 214 is provided with a first oil hole 2140 and a second oil hole 2142 that are axially connected. The first oil holes 2140 are connected in sequence to form the first oil cooling channel 210, and the second oil holes 2142 are connected in sequence to form the second oil cooling channel 211. In one embodiment, the first oil hole 2140 on each lamination stack 214 is a straight-through structure, and the first oil holes 2140 of multiple lamination stacks 214 are straight-through to form the first oil cooling channel 210 of the straight-through structure. Similarly, the second oil hole 2142 on each lamination stack 214 is a straight-through structure, and the second oil holes 2142 of multiple lamination stacks 214 are straight-through to form the second oil cooling channel 211 of the straight-through structure, but it is not limited thereto.
[0057] Please refer to Figure 4 , Figure 4 It is a schematic diagram showing that the first oil holes 2140 of each lamination set 214 are connected.
[0058] In this embodiment, in order to increase the contact area between the oil and the lamination stack 214 in the first oil cooling channel 210, it can be achieved by changing the area of the connection point between the two first oil holes 2140 of two adjacent lamination stacks 214. Specifically, in at least two adjacent lamination stacks 214, the flow area S of the first oil holes 2140 of the lamination stack 214 close to the first oil inlet 2100 is larger than the connection area S' of the two first oil holes 2140 of the two adjacent lamination stacks 214 at the connection point. After such arrangement, when the oil flows from the first oil holes 2140 of the left lamination stack 214 into the first oil holes 2140 of the right lamination stack 214, since the connection area S' becomes smaller, the oil encounters resistance during the circulation process and will contact the outer portion A of the first oil holes 2140 of the left lamination stack 214, thereby increasing the contact area between the oil and the left lamination stack 214 and improving the heat exchange effect. Figure 4 In the illustrated embodiment, the connection area S′ of two adjacent first oil holes 2140 at the connection point is smaller than the flow area of the first oil holes 2140 , so that the contact area between the plurality of lamination stacks 214 and the oil is increased.
[0059] There is no limitation on the way to reduce the connection area S'. In one embodiment, the flow area of the first oil hole 2140 of the left lamination group 214 can be set to be larger than the flow area of the first oil hole 2140 of the right lamination group 214.
[0060] In some other embodiments, the flow areas of the first oil holes 2140 of two adjacent lamination groups 214 are equal, and the two adjacent first oil holes 2140 are partially staggered and partially connected along the circumferential direction of the stator core 21. In this way, the two adjacent first oil holes 2140 can be offset in the circumferential direction. When the cooling oil flows from the first oil holes 2140 of the left lamination group 214 into the first oil holes 2140 of the right lamination group 214, the area of the right lamination group 214 located outside the first oil holes 2140 will contact the cooling oil, increasing the contact area between the right lamination group 214 and the cooling oil, and the cooling effect is enhanced. In addition, in this embodiment, the lamination group 214 can be formed by stacking the same laminations, so that the types of molds for punching the laminations can be reduced, which is conducive to reducing the manufacturing cost of the laminations.
[0061] In one embodiment, in order to increase the contact area between the cooling oil in the second oil cooling channel 211 and the lamination stack 214, the same implementation as above can be adopted. Specifically, among the multiple lamination stacks 214, at least two adjacent lamination stacks 214, the flow area of the second oil holes 2142 of the lamination stack 214 near the second oil inlet 2110 is greater than the connection area at the connection point of the two second oil holes 2142 of the two adjacent lamination stacks 214. The setting of the flow area of the second oil holes 2142 in each lamination stack 214 and the alignment of the second oil holes 2142 can refer to the first oil holes 2140, and will not be repeated here.
[0062] Please refer to Figure 1 and Figure 5 , Figure 5 Shown is a schematic diagram of the first oil ring 40 .
[0063] In one embodiment, the oil-cooled motor 1 further comprises a first oil ring 40, which is disposed at the first end 212 of the stator core 21, and is coaxial with the stator core 21. In one embodiment, a sealing ring 41 is sleeved on one end of the first oil ring 40 axially away from the stator core 21, and the sealing ring 41 is clamped between the housing 10 and the first oil ring 40 along the radial direction of the first oil ring 40, and is used to seal the gap between the housing 10 and the first oil ring 40, and can seal the passage between the housing oil inlet 102 and the first oil inlet 2100.
[0064] In one embodiment, the first oil ring 40 includes a first oil inlet cavity 401 connected to the first oil inlet 2100, and a first oil outlet cavity 402 connected to the second oil outlet 2112, wherein the first oil inlet cavity 401 is also connected to the housing oil inlet 102, thereby allowing the cooling oil to flow into the first oil inlet 2100 according to a preset path, and to flow to other parts of the motor stator 20 according to a preset path after flowing out from the second oil outlet 2112. In addition, the first oil ring 40 can also omit the oil pipe, which is conducive to simplifying the structure of the stator 20 and improving the compactness of the stator 20. The first oil inlet cavity 401 and the first oil outlet cavity 402 are distributed on the same circumference with the axis of the first oil ring 40 as the center.
[0065] The present application does not limit the specific structure of the first oil ring 40. In one embodiment, the outer surface of the first oil ring 40 is formed with a first groove 403 and a first boss 404 arranged circumferentially and extending axially, and the first groove 403 is formed as the first oil inlet cavity 401. The first groove 403 extends axially, and the end of the first groove 403 away from the stator core 21 is sealed by a sealing ring 41 and is sealed and connected to the oil inlet 102 of the housing, and the end of the first groove 403 close to the stator core 21 is connected to the first oil inlet 2100. The first boss 404 is provided with the first oil outlet cavity 402 on one side end surface facing the stator core 21, and the first oil outlet cavity 402 extends axially in the boss 404. In this solution, the first oil inlet chamber 401 is formed by opening a first groove 403, and the first oil outlet chamber 402 is formed by opening a cavity in the first boss 404, thereby achieving isolation between the first oil inlet chamber 401 and the first oil outlet chamber 402, and the first oil inlet chamber 401 and the first oil outlet chamber 402 are formed in a simple manner, which is convenient for processing and manufacturing.
[0066] In the embodiment with multiple first cooling oil passages 210 and multiple second cooling oil passages 211, the first oil ring 40 may be provided with multiple first oil inlet cavities 401 and multiple first oil outlet cavities 402. The first oil inlet cavities 401 and the first oil outlet cavities 402 may be interlaced.
[0067] In one embodiment, a first oil injection hole 400 is formed on the inner surface of the first oil ring 40, the first oil injection hole 400 is communicated with the first oil outlet cavity 402, the stator 20 includes a stator winding 22, and the first oil injection hole 400 is directly opposite to the stator winding 22. In this way, the cooling oil flowing out of the first oil outlet cavity 402 can further radially cool the stator winding 22 through the radially extending first oil injection hole 400, without the need to separately set an oil channel for cooling the stator winding 22.
[0068] Please refer to Figure 6 and Figure 7 , Figure 6 FIG. 1 is a schematic diagram showing that the first oil ring 40 and the second oil ring 50 are assembled at two ends of the stator core 21 . Figure 7 Shown Figure 6 Schematic diagram of part of the structure shown in .
[0069] like Figure 6 As shown, in one embodiment, the plurality of first oil inlet chambers 401 are connected to each other at one end axially away from the stator core 21 , and the plurality of first oil inlet chambers 401 are all connected to the housing oil inlet 102 through the first annular groove 405 .
[0070] like Figure 7As shown, multiple first oil inlets 2100 can be commonly connected to a first oil inlet chamber 401, and multiple second oil outlets 2112 can be commonly connected to a first oil outlet chamber 402, thereby reducing the number of first oil inlet chambers 401 and first oil outlet chambers 402, and correspondingly reducing the number of first grooves 403 and first bosses 404, which is beneficial to simplifying the structure of the first oil ring 40.
[0071] Please refer to Figure 1 , Figure 6 and Figure 7 In one embodiment, the motor stator 20 also includes a second oil ring 50 disposed at the second end 213, the second oil ring 50 is coaxial with the stator core 21, and the second oil ring 50 includes a second oil inlet chamber 501 connected to the second oil inlet port 2110, and a second oil outlet chamber 502 connected to the first oil outlet port 2102.
[0072] A second sealing ring 51 is sleeved on one end of the second oil ring 50 away from the stator core 21. The second sealing ring 51 is clamped between the housing 10 and the second oil ring 50 along the radial direction of the second oil ring 50 to seal the gap between the housing 10 and the second oil ring 50. The second oil inlet cavity 501 communicates with the housing oil inlet 102 and the second oil inlet 2110, and the second oil inlet cavity 501 is sealed and communicated with the housing oil inlet 102 through the second sealing ring 51. There are two shell oil inlets 102, and the stator core 21 is axially spaced apart. One shell oil inlet 102 is connected to the first oil inlet 2100 through the first annular groove 405 and the first oil inlet cavity 401, and one shell oil inlet 102 is connected to the second oil inlet 2110 through the second annular groove 505 and the second oil inlet cavity 501, so that oil can be simultaneously fed from both axial ends of the stator core 21. Therefore, the present application realizes a pioneering "oil inlet at both ends, oil outlet at both ends" oil circuit structure, and the maximum core flow coefficient of a single cooling oil circuit (the ratio of the core oil channel flow to the inlet flow) can reach 1, thereby improving the cooling efficiency.
[0073] In the embodiment with multiple first cooling oil passages 210 and multiple second cooling oil passages 211, the second oil ring 50 may be provided with multiple second oil inlet cavities 501 and multiple second oil outlet cavities 502. The second oil inlet cavities 501 and the second oil outlet cavities 502 may be arranged alternately.
[0074] The plurality of second oil inlet chambers 501 are connected to each other at one end axially away from the stator core 21 , and the plurality of second oil inlet chambers 501 are all connected to the housing oil inlet port 102 .
[0075] In one embodiment, the outer surface of the second oil ring 50 is formed with a second groove 503 and a second boss 504 that are circumferentially distributed and axially extended, the second groove 503 is formed as the second oil inlet cavity 501, and the second boss 504 is provided with the second oil outlet cavity 502 on one end surface facing the stator core 21, and the second oil outlet cavity 502 extends axially.
[0076] Multiple second oil inlets 2110 can be commonly connected to a second oil inlet chamber 501, and multiple first oil outlets 2102 can be commonly connected to a second oil outlet chamber 502, thereby reducing the number of second oil inlet chambers 501 and second oil outlet chambers 502, and correspondingly reducing the number of second grooves 503 and second bosses 504, which is conducive to simplifying the structure of the second oil ring 50.
[0077] In one embodiment, the inner surface of the second oil ring 50 is formed with a second oil injection hole 500 (refer to Figure 1 ), the second oil injection hole 500 is connected to the second oil outlet cavity 502, and the second oil injection hole 500 is directly opposite to the stator winding 22. In this way, the cooling oil flowing out of the second oil outlet cavity 502 can further radially cool the stator winding 22 through the radially extending second oil injection hole 500, and there is no need to separately set up an oil channel for cooling the stator winding 22.
[0078] exist Figure 1 In the illustrated embodiment, the first oil injection hole 400 radially faces the stator winding 22 at the first end 212, and the second oil injection hole 500 radially faces the stator winding 22 at the second end 213, thereby radially cooling the two stator windings 22 of the stator 20 respectively.
[0079] In this embodiment, the first oil ring 40 and the second oil ring 50 have the same structure. The first oil ring 40 and the second oil ring 50 can be preferably made of plastics with oil-resistant and high-temperature-resistant properties, including but not limited to polyamide, high-temperature-resistant nylon, and polyphenylene sulfide.
[0080] The stator core 21 and the stator winding 22 in the present application are fully and evenly cooled, which effectively reduces the risk of high-temperature aging failure of the motor system insulation, while improving the motor power density and torque density.
[0081] In the oil-cooled motor provided by the present application, the cooling oil enters from the first oil ring 40, passes through the first cooling oil channel 210 of the stator core 21, enters the second oil ring 50, and then sprays out, so that the flow rate of the internal cooling of the stator core 21 and the end cooling is the same. Similarly, the cooling oil enters from the second oil ring 50, passes through the second cooling oil channel 211 of the stator core 21, enters the first oil ring 40, and then sprays out, so that the flow rate of the internal cooling of the stator core 21 and the end cooling is the same.
[0082] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present application shall be included in the scope of protection of the present application.
Claims
1. An oil-cooled motor, characterized in that: The invention comprises a housing and a motor stator, wherein the housing is provided with a first housing oil inlet and a second housing oil inlet which are arranged at intervals in the axial direction of the housing, and the motor stator is arranged in the housing and comprises: A stator core with a hollow cylindrical structure, wherein the stator core includes a first end and a second end in an axial direction, and the stator core has a single-layer oil cooling channel located on the same circumference with the axis of the stator core as the center, and the oil cooling channel passes through the stator core along the axial direction, and the oil cooling channel is arranged away from the axis of the stator core and includes a plurality of first oil cooling channels and a plurality of second oil cooling channels, and the plurality of first oil cooling channels and the plurality of second oil cooling channels are alternately arranged in the circumferential direction of the stator core, the first oil cooling channel forms a first oil inlet at the first end and a first oil outlet at the second end, and the second oil cooling channel forms a second oil outlet at the first end and a second inlet at the second end. The stator core comprises a plurality of lamination groups stacked along the axial direction, each of the lamination groups is provided with a first oil hole and a second oil hole extending along the axial direction, the first oil holes are sequentially connected to form the first oil cooling channel, and in at least two adjacent lamination groups, the flow area of the first oil hole of the lamination group close to the first oil inlet is larger than the connection area of the two first oil holes of the two adjacent lamination groups at the connection point, and the second oil holes are sequentially connected to form the second oil cooling channel, and in at least two adjacent lamination groups, the flow area of the second oil hole of the lamination group close to the second oil inlet is larger than the connection area of the two second oil holes of the two adjacent lamination groups at the connection point; a first oil ring disposed at the first end, the first oil ring being provided with a first oil inlet cavity opposite to and in communication with the first oil inlet in the axial direction, and a first oil outlet cavity opposite to and in communication with the second oil outlet in the axial direction, the first oil outlet cavity and the first oil inlet cavity being arranged at intervals in the circumferential direction of the first oil ring, and the first oil inlet cavity being in communication with the first housing oil inlet; A second oil ring is arranged at the second end, the second oil ring is provided with a second oil inlet chamber opposite to and connected to the second oil inlet in the axial direction, and is provided with a second oil outlet chamber opposite to and connected to the first oil outlet in the axial direction, the second oil outlet chamber and the second oil inlet chamber are arranged at intervals in the circumferential direction of the second oil ring, the second oil inlet chamber is connected to the second housing oil inlet, the second oil inlet chamber and the first oil inlet chamber are arranged opposite to each other in the axial direction, and the second oil outlet chamber and the first oil outlet chamber are arranged opposite to each other in the axial direction.
2. The oil-cooled motor according to claim 1, characterized in that: The first oil holes of two adjacent lamination groups have the same flow area and are partially staggered and partially connected along the circumference of the stator core to form the first oil cooling channel; The flow areas of the second oil holes in two adjacent lamination groups are the same and are partially staggered and partially connected along the circumference of the stator core to form the second oil cooling channel.
3. The oil-cooled motor according to claim 1, characterized in that: The stator comprises a stator winding, The inner circumferential surface of the first oil ring is provided with a first oil injection hole extending in the radial direction of the first oil ring, the first oil injection hole is communicated with the first oil outlet cavity, and the first oil injection hole and one end of the stator winding in the axial direction are directly opposite to each other in the radial direction of the first oil ring; and / or, The inner surface of the second oil ring is provided with a second oil injection hole extending in the radial direction of the second oil ring, the second oil injection hole is communicated with the second oil outlet cavity, and the second oil injection hole is opposite to the other axial end of the stator winding in the radial direction of the second oil ring.
4. The oil-cooled motor according to claim 3, characterized in that: The oil enters the stator core from the first housing oil inlet and the second housing oil inlet respectively. The oil entering from the first housing oil inlet enters the first oil cooling channel through the first oil inlet cavity and the first oil inlet, flows into the second oil outlet cavity through the first oil outlet, and radially sprays to the other end of the stator winding in the axial direction through the second oil spray hole. The cooling oil entering from the second housing oil inlet enters the second oil cooling channel through the second oil inlet cavity and the second oil inlet, flows into the first oil outlet cavity through the second oil outlet, and is radially sprayed to one axial end of the stator winding through the first oil spray hole.
5. The oil-cooled motor according to claim 3, characterized in that: The outer surface of the first oil ring is formed with first grooves and first bosses spaced apart along the circumference thereof, the first groove forms the first oil inlet cavity, the end surface of the first boss facing the first end is provided with the first oil outlet cavity, and the first oil outlet cavity extends in the axial direction. The outer surface of the second oil ring is formed with a second groove and a second boss which are arranged at intervals along the circumference thereof, the second groove forms the second oil inlet cavity, the end surface of the second boss facing the second end is provided with the second oil outlet cavity, and the second oil outlet cavity extends in the axial direction. The first groove and the second boss correspondingly communicated therewith are arranged opposite to each other in the axial direction, and the second groove and the first boss correspondingly communicated therewith are arranged opposite to each other in the axial direction.
6. The oil-cooled motor according to claim 5, characterized in that: The first groove penetrates the first oil ring in a radial direction of the first oil ring, and the first oil outlet cavity extends in a radial direction and a circumferential direction of the first oil ring; and / or, The second groove penetrates the second oil ring in a radial direction of the second oil ring, and the second oil outlet cavity extends in a radial direction and a circumferential direction of the second oil ring.
7. The motor stator according to claim 5, characterized in that: There are a plurality of the first grooves and the first bosses, the plurality of the first grooves and the plurality of the first bosses are alternately arranged in the axial direction of the first oil ring, the plurality of the first grooves form a plurality of the first oil inlet chambers, and the plurality of the first oil inlet chambers are communicated with the oil inlet port of the first housing; There are multiple second grooves and multiple second bosses, and the multiple second grooves and multiple second bosses are alternately arranged in the axial direction of the second oil ring. The multiple second grooves form multiple second oil inlet chambers, and the multiple second oil inlet chambers are connected to the oil inlet port of the second housing.
8. The oil-cooled motor according to claim 7, characterized in that: A plurality of the first oil inlets are connected to one first oil inlet cavity, and a plurality of the second oil outlets are connected to one first oil outlet cavity; and / or, A plurality of the second oil inlets are commonly communicated with one second oil inlet chamber, and a plurality of the first oil outlets are commonly communicated with one second oil outlet chamber.
9. The oil-cooled motor according to claim 7, characterized in that: The outer surface of the first oil ring is provided with a first annular groove extending along the circumference of the first oil ring, the first annular groove is on the side of the first boss away from the first end, the first annular groove is connected with the first housing oil inlet and the plurality of first grooves; and / or, The outer surface of the second oil ring is provided with a second annular groove extending along the circumference of the second oil ring. The second annular groove is formed on the side of the second boss away from the second end. The second annular groove is connected to the second housing oil inlet and multiple second grooves.
10. The oil-cooled motor according to claim 9, characterized in that: The oil enters the stator core from the first housing oil inlet and the second housing oil inlet respectively. The oil entering from the first housing oil inlet flows into the first plurality of first grooves through the first annular groove, enters the first oil cooling channel through the first oil inlet, flows into the second oil outlet cavity through the first oil outlet, and then radially sprays to the other end of the stator winding in the axial direction through the second oil injection hole. The cooling oil entering from the oil inlet of the second housing flows into the plurality of second grooves through the second annular groove respectively, enters the second oil cooling channel through the second oil inlet, flows into the first oil outlet cavity through the second oil outlet, and is radially sprayed to one end of the stator winding in the axial direction through the first oil injection hole.