Motor cooling structure, motor and automobile

Abstract

The utility model relates to a motor cooling structure, a motor and an automobile, the motor cooling structure comprises a shell, a mounting cavity is formed in the shell, an oil way structure is arranged on the inner wall, defined by the shell, of the mounting cavity, and the oil way structure is used for communicating with an external oil supply device; the stator assembly is arranged on the inner wall of the mounting cavity and is communicated with the oil path structure; the rotor assembly is inserted into the stator assembly, the rotor assembly comprises a rotor shaft and a rotor iron core, and the rotor shaft is provided with an oil inlet channel extending in the axial direction of the rotor shaft and an oil passing channel extending in the radial direction of the rotor shaft; the oil inlet channel is communicated with the oil passing channel and used for being communicated with an external oil supply device, the rotor iron core is arranged outside the rotor shaft in a sleeving mode, the rotor iron core is provided with a cooling channel which extends in the axial direction and penetrates through the two ends of the rotor iron core, and two channel openings of the cooling channel correspond to coil inner rings of the stator assembly respectively.

Description

Technical Field

[0001] The present application relates to the technical field of motor heat dissipation and temperature reduction, and in particular to a motor cooling structure, an electric motor, and a vehicle. Background Art

[0002] Electric motors are the main power source for new energy vehicles. Since they need to output a lot of power to support the vehicle's driving, they will generate a lot of heat during operation. If this heat is not dissipated in time, it will inevitably affect the motor's working performance and reliability.

[0003] In traditional technology, electric motors use cooling oil circuit designs to achieve the purpose of cooling and lowering the temperature. However, traditional cooling oil circuit designs usually only involve slotting or digging holes in the stator core so that the cooling oil can cool the stator core when flowing through the slots or holes. However, this method places very high demands on the molds used to process the stamping sheets of the stator core, resulting in increased mold costs. In addition, if only the stator core is designed with a cooling oil circuit, but the rotor core does not pass cooling oil, the heat generated by the rotor core and the magnets will be difficult to dissipate, resulting in the risk of demagnetization of the magnets, which will potentially have a significant impact on the performance of the motor. Summary of the Invention

[0004] Based on this, it is necessary to provide a motor cooling structure, a motor and a car to address the problems of high cooling cost and demagnetization of magnetic steel affecting the performance of the motor.

[0005] In a first aspect of the present application, a motor cooling structure is provided, comprising:

[0006] A housing, wherein a mounting cavity is formed inside the housing, and an inner wall of the housing surrounding the mounting cavity is provided with an oil path structure, wherein the oil path structure is used to connect to an external oil supply device;

[0007] a stator assembly, the stator assembly being mounted on the inner wall of the mounting cavity and communicating with the oil circuit structure; and

[0008] A rotor assembly is inserted into the interior of the stator assembly, and the rotor assembly includes a rotor shaft and a rotor core. The rotor shaft is provided with an oil inlet channel extending along its axial direction and an oil flow channel extending along its radial direction. The oil inlet channel is connected to the oil flow channel and is used to connect to an external oil supply device. The rotor core is sleeved on the outside of the rotor shaft, and the rotor core is provided with a cooling channel extending along the axial direction and passing through both ends of the rotor core. The two channel openings of the cooling channel are respectively provided corresponding to the inner ring of the winding package of the stator assembly.

[0009] In the motor cooling structure of this scheme, after the casing, stator assembly and rotor assembly are assembled, the oil circuit structure and the oil inlet channel can be connected to the external oil supply device (for supplying cooling oil) respectively. When the motor is running, the external oil supply device will respectively deliver cooling oil to the oil circuit structure and the oil inlet channel. On the one hand, the cooling oil flowing through the oil circuit structure will contact the stator assembly to transfer heat, and the cooling oil absorbs the heat generated by the stator assembly, thereby cooling the stator assembly. Compared with traditional technologies, the oil circuit structure is processed and formed on the casing, and the processing method is simple, without the need to groove or drill holes on the stator assembly, thereby reducing the mold cost for manufacturing the stator core; on the other hand, the cooling oil flowing into the oil inlet channel further flows into the cooling channel through the oil passage, and can then transfer heat with the rotor core. The cooling oil absorbs the heat generated by the rotor core and the magnet during operation, thereby cooling the rotor core and the magnet, avoiding the problem of demagnetization caused by excessive temperature of the magnet, and avoiding affecting the performance of the motor.

[0010] The technical solution of this application is further described below:

[0011] In one embodiment, the oil passage structure includes an annular oil passage groove, which extends along the circumferential direction of the inner wall of the mounting cavity and is a closed-loop structure.

[0012] In one embodiment, the oil circuit mechanism further includes at least a first axial oil groove and a second axial oil groove, the first axial oil groove being arranged along the axial extension of the inner wall of the mounting cavity and being arranged on one axial side of the annular oil groove, the second axial oil groove being arranged along the axial extension of the inner wall of the mounting cavity and being arranged on the other axial side of the annular oil groove, and both the first axial oil groove and the second axial oil groove are connected to the annular oil groove.

[0013] In one embodiment, the number of the oil passages is multiple, and the multiple oil passages are arranged at intervals along the circumferential direction of the rotor shaft.

[0014] In one embodiment, the oil passage includes an oil inlet directly connected to the oil inlet passage and an oil outlet directly connected to the cooling passage, and the cross-sectional area of ​​the oil passage decreases along the direction from the oil inlet to the oil outlet.

[0015] In one embodiment, a partition is provided in the middle of the oil inlet channel, and the partition divides the oil inlet channel into a first oil inlet chamber and a second oil inlet chamber. The plurality of oil passages are staggered in the axial direction of the rotor shaft to form a first oil passage group and a second oil passage group. The first oil passage group is connected to the first oil inlet chamber, and the second oil passage group is connected to the second oil inlet chamber.

[0016] In one embodiment, the cross section of the cooling channel is configured as a water drop-shaped structure, wherein the wide diameter end of the water drop-shaped structure is arranged close to the rotor shaft and the narrow diameter end is arranged away from the rotor shaft.

[0017] In one embodiment, the motor cooling structure further includes a first balancing disk and a second balancing disk, wherein the first balancing disk is sleeved on the outside of the rotor shaft and abuts against one axial end of the rotor core, and the second balancing disk is sleeved on the outside of the rotor shaft and abuts against the other axial end of the rotor core;

[0018] The first balancing disc and the second balancing disc are both provided with oil-swinging holes penetrating in the thickness direction thereof, and the oil-swinging holes are respectively arranged toward the inner coil ring of the stator assembly.

[0019] In a second aspect of the present application, an electric motor is further provided, which includes the motor cooling structure as described above.

[0020] According to a third aspect of the present application, a car is provided, which includes the electric motor as described above. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The drawings that constitute a part of this application are used to provide further understanding of this application. The illustrative embodiments of this application and their descriptions are used to explain this application and do not constitute improper limitations on this application.

[0022] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0023] FIG1 is a schematic diagram of an axial cross-sectional structure of a motor cooling structure according to an embodiment of the present application.

[0024] FIG2 is a cross-sectional structural diagram of the rotor assembly in FIG1 .

[0025] Figure 3 Schematic diagram of the structure of a casing according to an embodiment.

[0026] Figure 4 Schematic diagram of the structure of a rotor shaft according to an embodiment.

[0027] Figure 5 This is a structural diagram of the end face of the rotor core according to one embodiment.

[0028] Figure 6 It is a structural schematic diagram of the first balancing disk.

[0029] Description of reference numerals:

[0030] 100. Motor cooling structure; 10. Casing; 11. Oil circuit structure; 111. Annular oil groove; 112. First axial oil groove; 113. Second axial oil groove; 12. Mounting cavity; 20. Stator assembly; 30. Rotor assembly; 31. Rotor shaft; 311. Oil inlet channel; 312. Oil passage; 32. Rotor core; 321. Cooling channel; 40. First balancing disk; 50. Second balancing disk; 40a. Oil-spinning hole. DETAILED DESCRIPTION

[0031] To make the above-mentioned objects, features, and advantages of the present application more clearly understood, the specific embodiments of the present application are described in detail below with reference to the accompanying drawings. The following description sets forth many specific details to facilitate a full understanding of the present application. However, the present application can be implemented in many other ways than those described herein, and those skilled in the art can make similar improvements without violating the scope of the present application. Therefore, the present application is not limited to the specific embodiments disclosed below.

[0032] In the description of this application, it should be understood that if the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. appear, the orientation or position relationship indicated by these terms is based on the orientation or position relationship shown in the accompanying drawings, which is only for the convenience of describing this application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on this application.

[0033] In addition, if the terms "first" or "second" appear, these terms are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the number of technical features indicated. Therefore, a feature specified as "first" or "second" may explicitly or implicitly include at least one of such features. In the description of this application, if the term "plurality" appears, "plurality" means at least two, for example, two, three, etc., unless otherwise specifically defined.

[0034] In this application, unless otherwise specified or limited, the terms "mounted," "connected," "connected," "fixed," etc., should be interpreted broadly. For example, these terms may refer to fixed connections, removable connections, or integration; mechanical connections or electrical connections; direct connections or indirect connections through an intermediary; and internal communication between two components or interaction between two components, unless otherwise specified. Those skilled in the art will understand the specific meanings of these terms in this application based on the specific circumstances.

[0035] In this application, unless otherwise expressly specified or limited, if a first feature is described as being "above" or "below" a second feature, or similar descriptions, this may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. Furthermore, when a first feature is described as being "above," "above," or "above" a second feature, it may mean that the first feature is directly above or diagonally above the second feature, or simply means that the first feature is at a higher level than the second feature. When a first feature is described as being "below," "below," or "below" a second feature, it may mean that the first feature is directly below or diagonally below the second feature, or simply means that the first feature is at a lower level than the second feature.

[0036] It should be noted that if an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be an intermediate element. If an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be an intermediate element. If any, the terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used in this application are for illustrative purposes only and do not represent the only embodiment.

[0037] See Figures 1 to Figure 4 , is a motor cooling structure 100 shown in one embodiment of the present application, which includes a housing 10, a stator assembly 20 and a rotor assembly 30. Among them, the housing 10 is made of metal material and is a cylindrical structure with two ends passing through, which plays the role of a carrier.

[0038] The housing 10 has an interior formed with a mounting cavity 12. An oil passage 11 is provided on the inner wall of the housing 10 surrounding the mounting cavity 12. The oil passage 11 is used to connect to an external oil supply device. The oil passage 11 can be formed by machining, chemical etching, or other methods, which is simple and inexpensive.

[0039] The stator assembly 20 is mounted on the inner wall of the mounting cavity 12 and communicates with the oil circuit structure 11. Preferably, the stator assembly 20 forms a tight fit with the inner wall of the mounting cavity 12, allowing the stator assembly 20 to be mounted and fixed within the housing 10. This not only ensures a stable assembly of the stator assembly 20 and the housing 10, but also provides a seal for the oil circuit structure 11 through the outer wall of the stator assembly 20, preventing leakage of the cooling oil flowing through the oil circuit structure 11.

[0040] The rotor assembly 30 is inserted into the stator assembly 20 and can rotate relative to the stator assembly 20. The rotor assembly 30 rotates relative to the stator assembly 20 to cut the magnetic field and generate current.

[0041] The rotor assembly 30 includes a rotor shaft 31 and a rotor core 32. The rotor shaft 31 is provided with an oil inlet channel 311 extending along its axial direction and an oil flow channel 312 extending along its radial direction. The oil inlet channel 311 is connected to the oil flow channel 312 and is used to connect to an external oil supply device. The rotor core 32 is sleeved on the outside of the rotor shaft 31, and the rotor core 32 is provided with a cooling channel 321 extending along the axial direction and passing through both ends of the rotor core 32. The two channel openings of the cooling channel 321 are respectively provided corresponding to the inner ring of the winding package of the stator assembly 20.

[0042] The rotor core 32 specifically includes a plurality of rotor punchings, which are stacked to form the rotor core 32. The rotor punchings can be made of magnetic steel material.

[0043] In summary, the implementation of the technical solution of this embodiment will have the following beneficial effects: in the motor cooling structure 100 of this solution, after the housing 10, the stator assembly 20 and the rotor assembly 30 are assembled, the oil circuit structure 11 and the oil inlet channel 311 can be connected to the external oil supply device (for supplying cooling oil) respectively. When the motor is running, the external oil supply device will respectively deliver cooling oil to the oil circuit structure 11 and the oil inlet channel 311. On the one hand, the cooling oil flowing through the oil circuit structure will contact with the stator assembly 20 to transfer heat, and the cooling oil absorbs the heat generated by the stator assembly 20, thereby cooling the stator assembly 20. Compared with traditional technology, the oil circuit structure 11 is processed and formed on the casing 10, and the processing method is simple, without the need to groove or drill holes on the stator assembly 20, thereby reducing the mold cost for manufacturing the stator core; on the other hand, the cooling oil flowing in from the oil inlet channel 311 further flows into the cooling channel 321 through the oil passage 312, and then can transfer heat with the rotor core 32. The cooling oil absorbs the heat generated by the rotor core 32 and the magnet during operation, thereby cooling the rotor core 32 and the magnet, avoiding the problem of demagnetization caused by excessive temperature of the magnet, and avoiding affecting the performance of the motor.

[0044] The direction of the arrow in Figure 1 indicates the flow direction of the cooling oil during operation.

[0045] It is understood that the external oil supply device described above can specifically be a cooling oil tank, which is equipped with an oil pump, an oil delivery pipe, and an oil return pipe. The oil delivery pipe connects the cooling oil tank to the oil circuit structure 11 and the oil inlet channel 311. The oil pump is located in the cooling oil tank or the oil delivery pipe to provide the power required for the cooling oil to flow. The oil return pipe connects the cooling oil tank to the oil circuit structure and the cooling channel 321, allowing the cooling oil to flow back to the cooling oil tank, thus achieving cooling oil recycling.

[0046] Please continue reading Figure 3 In one embodiment, the oil passage structure 11 includes an annular oil groove 111 extending circumferentially along the inner wall of the mounting cavity 12 and forming a closed loop. Annular oil groove 111 surrounds the outer circumference of the stator assembly 20. Therefore, the cooling oil flowing through annular oil groove 111 can achieve comprehensive and effective heat exchange cooling of the outer ring of the stator assembly 20, ensuring a stable temperature drop for the stator assembly 20.

[0047] Furthermore, the oil passage mechanism includes at least a first axial oil groove 112 and a second axial oil groove 113. The first axial oil groove 112 is provided along the axial direction of the inner wall of the mounting cavity 12 and is arranged on one axial side of the annular oil groove 111. The second axial oil groove 113 is provided along the axial direction of the inner wall of the mounting cavity 12 and is arranged on the other axial side of the annular oil groove 111. The first axial oil groove 112 and the second axial oil groove 113 are both connected to the annular oil groove 111. A portion of the cooling oil flowing into the annular oil groove 111 will simultaneously flow into the first axial oil groove 112 and the second axial oil groove 113, respectively, and then flow along the first axial oil groove 112 and the second axial oil groove 113 to the two ends of the stator assembly 20, thereby contacting the outer ring of the winding package at the end of the stator assembly 20, absorbing heat and achieving the purpose of cooling.

[0048] Please refer to Figure 2 and Figure 4 Furthermore, based on any of the above embodiments, a plurality of oil passages 312 are provided, and the plurality of oil passages 312 are arranged at intervals along the circumferential direction of the rotor shaft 31. Thus, each oil passage 312 is directed to a different portion of the rotor core 32, thereby simultaneously delivering cooling oil from the oil inlet passage 311 to different portions of the rotor core 32. This ensures a consistent cooling effect across all portions of the rotor core 32, preventing localized high temperatures from affecting the rotor core 32 and the magnets.

[0049] Furthermore, the oil passage 312 includes an oil inlet directly connected to the oil inlet channel 311 and an oil outlet directly connected to the cooling channel 321. The cross-sectional area of ​​the oil passage 312 decreases along the direction from the oil inlet to the oil outlet. It is easy to understand that, on the one hand, the cooling oil has a relatively high viscosity and a slightly poor fluidity. On the other hand, the dimensions of the processed oil inlet channel 311, oil passage 312, and cooling channel 321 should not be too large to avoid affecting the strength and performance of the rotor shaft 31 and the rotor core 32. Therefore, in order to improve the smoothness and effectiveness of the cooling oil flowing from the oil inlet channel 311 to the cooling channel 321, the oil passage 312 is designed to have a decreasing cross-sectional area from the oil inlet to the oil outlet. This can produce a pressurization effect on the cooling oil flowing through the oil passage 312, thereby increasing the kinetic energy of the cooling oil and enhancing the flow capacity of the coolant.

[0050] In another embodiment, a partition is provided in the middle of the oil inlet channel 311, which divides the oil inlet channel 311 into a first oil inlet chamber and a second oil inlet chamber. A plurality of oil passages 312 are staggered in the axial direction of the rotor shaft 31 to form a first oil passage 312 group and a second oil passage 312 group. The first oil passage 312 group is connected to the first oil inlet chamber, and the second oil passage 312 group is connected to the second oil inlet chamber.

[0051] Compared with the case where the cooling oil only flows in from one end of the oil inlet channel 311 and then simultaneously passes through multiple oil passages 312 to flow into the cooling channel 321, which may result in problems such as untimely cooling oil supply and uneven distribution of cooling oil from each oil passage 312, the present embodiment adopts a first oil passage 312 group that is isolated from each other and is connected to the first oil inlet chamber, and a second oil passage 312 group that is connected to the second oil inlet chamber. By supplying oil from both sides of the first oil inlet chamber and the second oil inlet chamber at the same time, the cooling oil supply amount can be increased, and the cooling oil amount that passes through the first oil passage 312 group and the second oil passage 312 group and flows into the cooling channel 321 per unit time can be increased, so that more cooling oil can participate in the heat exchange operation with the rotor core 32 per unit time, so as to absorb and carry away more heat, thereby enhancing the cooling and temperature reduction efficiency of the rotor core 32 and the magnetic steel.

[0052] Please continue to refer to Figure 1 and Figure 6In another embodiment, the motor cooling structure 100 further includes a first balancing disc 40 and a second balancing disc 50. The first balancing disc 40 is sleeved onto the exterior of the rotor shaft 31 and abuts one axial end of the rotor core 32. The second balancing disc 50 is sleeved onto the exterior of the rotor shaft 31 and abuts the other axial end of the rotor core 32. Each of the first and second balancing discs 40 and 50 has an oil-swinging hole 40a extending through its thickness. The oil-swinging holes 40a are respectively positioned toward the inner windings of the stator assembly 20. Thus, the oil-swinging holes 40a utilize centrifugal force to more accurately sling cooling oil flowing out of the cooling channel 321 onto the inner windings of the stator assembly 20, thereby improving the cooling effect and preventing leakage of cooling oil due to the oil not being able to reach the inner windings of the stator assembly 20.

[0053] Please continue reading Figure 5 Preferably, the cross-section of the cooling channel 321 in this application is designed as a teardrop-shaped structure, with the wide end of the teardrop-shaped structure positioned closer to the rotor shaft 31 and the narrow end positioned further away from the rotor shaft 31. The teardrop-shaped cooling channel 321 not only reduces the weight of the rotor assembly 30 but also, in conjunction with the oil-slinging holes 40a of the first and second balancing discs 40, 50, provides cooling for a larger area of ​​the rotor core 32 and magnets.

[0054] In addition to the above, the present application further provides a vehicle, which includes an electric motor. The electric motor includes the motor cooling structure 100 as described in any of the above embodiments.

[0055] The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above-mentioned embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0056] The above-described embodiments merely represent several implementation methods of the present application. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that a person of ordinary skill in the art may make various modifications and improvements without departing from the spirit of the present application, all of which fall within the scope of protection of the present application. Therefore, the scope of protection of the present patent application shall be determined by the appended claims.

Claims

1. A motor cooling structure, characterized in that: include: A casing, wherein a mounting cavity is formed inside the casing, and an inner wall of the casing surrounding the mounting cavity is provided with an oil path structure, wherein the oil path structure is used to connect to an external oil supply device; a stator assembly, the stator assembly being mounted on the inner wall of the mounting cavity and being in communication with the oil circuit structure; and A rotor assembly, wherein the rotor assembly is inserted into the interior of the stator assembly, and the rotor assembly includes a rotor shaft and a rotor core. The rotor shaft is provided with an oil inlet passage extending along its axial direction and an oil passage extending along its radial direction. The oil inlet passage is connected with the oil passage and is used to connect to an external oil supply device. The rotor core is sleeved on the outside of the rotor shaft, and the rotor core is provided with a cooling channel extending along the axial direction and passing through both ends of the rotor core. The two channel openings of the cooling channel are respectively arranged corresponding to the inner ring of the coil package of the stator assembly.

2. The motor cooling structure according to claim 1, characterized in that: The oil passage structure comprises an annular oil passage groove, which is extended along the circumferential direction of the inner wall of the mounting cavity and is a closed-loop structure.

3. The motor cooling structure according to claim 2, characterized in that: The oil circuit structure also includes at least a first axial oil groove and a second axial oil groove, the first axial oil groove is arranged along the axial extension of the inner wall of the mounting cavity and is arranged on one axial side of the annular oil groove, the second axial oil groove is arranged along the axial extension of the inner wall of the mounting cavity and is arranged on the other axial side of the annular oil groove, and the first axial oil groove and the second axial oil groove are both connected to the annular oil groove.

4. The motor cooling structure according to claim 1, characterized in that: The oil passages are provided in a plurality, and the plurality of oil passages are arranged at intervals along the circumferential direction of the rotor shaft.

5. The motor cooling structure according to claim 1 or 4, characterized in that: The oil passage includes an oil inlet directly connected to the oil inlet passage and an oil outlet directly connected to the cooling passage. The cross-sectional area of ​​the oil passage presents a decreasing change along the direction from the oil inlet to the oil outlet.

6. The motor cooling structure according to claim 4, characterized in that: A partition is provided in the middle of the oil inlet channel, and the partition divides the oil inlet channel into a first oil inlet chamber and a second oil inlet chamber. The plurality of oil passages are staggered in the axial direction of the rotor shaft to form a first oil passage group and a second oil passage group. The first oil passage group is connected to the first oil inlet chamber, and the second oil passage group is connected to the second oil inlet chamber.

7. The motor cooling structure according to claim 1, characterized in that: The cross section of the cooling channel is set to a water drop-shaped structure, and the wide diameter end of the water drop-shaped structure is arranged close to the rotor shaft, and the narrow diameter end is arranged away from the rotor shaft.

8. The motor cooling structure according to claim 1, characterized in that: The motor cooling structure further includes a first balancing disk and a second balancing disk, wherein the first balancing disk is sleeved on the outside of the rotor shaft and abuts against one axial end of the rotor core, and the second balancing disk is sleeved on the outside of the rotor shaft and abuts against the other axial end of the rotor core; The first balancing disc and the second balancing disc are both provided with oil-swinging holes penetrating in the thickness direction thereof, and the oil-swinging holes are respectively arranged toward the inner ring of the coil package of the stator assembly.

9. An electric motor, characterized in that: The motor cooling structure comprises the motor cooling structure as claimed in any one of claims 1 to 8.

10. An automobile, characterized in that: Comprising the electric motor as claimed in claim 9.

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