End cover plate of motor rotor, motor rotor and motor

Abstract

The utility model provides an end portion cover plate of a motor rotor, the motor rotor and a motor, the end portion cover plate comprises a plate body, and the plate body is provided with an inner end face used for being in butt joint with the end face of a rotor iron core; the oil return channel is arranged in the plate body; the oil return channel is provided with an oil receiving opening and an oil return opening, and the oil receiving opening is used for receiving cooling oil flowing out of an outlet of the rotor iron core cooling oil channel; the oil return opening is used for guiding the cooling oil back to the rotor iron core; the oil return channel is communicated with the outside of the motor rotor through the oil discharge channel; the oil receiving opening and the oil return opening are formed in the inner end face. According to the utility model, the oil return channel receives the cooling oil flowing out from the outlet of the rotor core cooling oil channel through the oil receiving opening pair, and then guides the cooling oil back to the rotor core from the oil return opening, and the cooling oil can directly contact with the end face of the rotor core so as to directly cool the magnetic steel, so that the cooling effect of the end face of the rotor core is better; the overall heat dissipation efficiency of the motor is high, and the performance of the motor is improved.

Description

Technical Field

[0001] This utility model belongs to the field of motor technology, and in particular relates to an end cover plate of a motor rotor, a motor rotor, and a motor. Background Technology

[0002] With the continuous development of new energy vehicle technology, motors, as core components of new energy vehicles, are increasingly developing towards higher torque density and higher power density, which will place higher demands on the cooling and heat dissipation capabilities of motors.

[0003] Currently, most electric motors on the market use oil cooling. This involves creating cooling oil channels running axially through the rotor core. Cooling oil is delivered to these channels via the shaft, cooling the rotor core and magnets. The oil is then ejected through end plates. Existing end plates typically have oil ejection holes connected to the cooling oil channels, directly ejecting the oil. This results in ineffective contact between the oil and the rotor core end faces, leading to poor cooling of the magnets, low motor cooling efficiency, and consequently, poor motor performance. Utility Model Content

[0004] In view of the shortcomings of the prior art described above, the purpose of this utility model is to provide an end cover plate for a motor rotor, a motor rotor and a motor, to solve the problem that in the prior art, the cooling oil is directly thrown out from the end cover plate after passing through the cooling oil channel, without making effective contact with the end of the rotor core, resulting in poor cooling effect of the magnets on the end face of the rotor core.

[0005] To achieve the above and other related objectives, in one aspect, this utility model provides an end cover plate for a motor rotor, comprising:

[0006] The plate has an inner end face for contacting the end face of the rotor core;

[0007] An oil return channel is provided in the plate body; the oil return channel has an oil receiving opening and an oil return opening, the oil receiving opening is used to receive cooling oil flowing out from the outlet of the rotor core cooling oil channel; the oil return opening is used to guide the cooling oil back to the rotor core;

[0008] An oil drain channel, wherein the oil return channel is connected to the outside of the motor rotor through the oil drain channel;

[0009] Both the oil receiving opening and the oil return opening are located on the inner end face.

[0010] Furthermore, the oil return channel is an oil return groove provided on the inner end face, and the opening of the oil return groove includes the oil receiving opening and the oil return opening.

[0011] Furthermore, each of the oil return grooves is provided with at least one protrusion for guiding flow, the protrusion extending axially from the inner end face toward the side away from the outer end face along the rotor core axis.

[0012] Furthermore, the oil drain channel is arranged along the thickness direction of the plate, one end of the oil drain channel is an oil drain opening, and the other end of the oil drain channel is connected to the oil return channel.

[0013] Furthermore, the plate also has an outer end face that is opposite to the inner end face, the oil drain channel is a through hole that extends from the inner end face toward the outer end face, and the oil drain opening is located on the outer end face.

[0014] Furthermore, the through hole is an oblique hole, and the through hole is inclined outward along the radial direction of the plate from the inner end face to the outer end face.

[0015] Furthermore, the oil drain opening is located on the outer circumferential surface of the plate.

[0016] Furthermore, the oil drain opening is an oil drain notch or an oil drain hole.

[0017] On the other hand, this utility model provides a motor rotor, including the aforementioned end cover plate, rotor core and rotating shaft, wherein the end cover plate and rotor core are both sleeved on the rotating shaft, and the end cover plate is located on the end of the rotor core; the oil return channel is connected to the cooling oil channel of the rotor core.

[0018] Furthermore, the oil return channel is an oil return groove, and the outline of each oil return groove is consistent with the outline of the magnet slot of the motor rotor.

[0019] Furthermore, the plate is provided with a plurality of oil return grooves along the circumferential direction, and each of the oil return grooves corresponds to the cooling oil outlet of each of the rotor cores.

[0020] On the other hand, this utility model provides an electric motor, including the end cover plate of the motor rotor described above or the motor rotor described above.

[0021] As described above, this utility model has the following beneficial effects: By setting an oil return channel on the plate, the oil return channel receives the cooling oil flowing out of the rotor core cooling oil channel through the oil receiving opening, and then guides the cooling oil back to the rotor core through the oil return opening. The cooling oil can directly contact the end face of the rotor core, and then directly enter the magnet slot of the rotor core to directly cool the magnet. This results in a better cooling effect on the end face of the rotor core, high overall heat dissipation efficiency of the motor, and improved motor performance. Attached Figure Description

[0022] Figure 1One embodiment of the end cover plate provided by this utility model;

[0023] Figure 2 Another embodiment of the end cover plate provided by this utility model;

[0024] Figure 3 Another embodiment of the end cover plate provided by this utility model;

[0025] Figure 4 Another embodiment of the end cover plate provided by this utility model;

[0026] Figure 5 for Figure 4 A sectional view;

[0027] Figure 6 An exploded schematic diagram of the electronic rotor provided by this utility model.

[0028] Label Explanation

[0029] 10-End cover plate, 101-Inner end face, 102-Outer end face, 103-Oil return groove, 104-Oil drain channel, 105-Protrusion, 20-Rotor core, 201-Magnetic slot. Detailed Implementation

[0030] The following specific embodiments illustrate the implementation of this utility model. Those skilled in the art can easily understand other advantages and effects of this utility model from the content disclosed in this specification.

[0031] It should be understood that the structures, proportions, sizes, etc., illustrated in the accompanying drawings of this specification are only for illustrative purposes to aid those skilled in the art and are not intended to limit the implementation of this utility model. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in proportions, or adjustments to size, without affecting the effects and objectives of this utility model, should still fall within the scope of the technical content disclosed in this utility model. Furthermore, the terms such as "upper," "lower," "left," "right," "middle," and "one" used in this specification are merely for clarity of description and are not intended to limit the scope of implementation of this utility model. Changes or adjustments to their relative relationships, without substantially altering the technical content, should also be considered within the scope of implementation of this utility model.

[0032] In order to describe the present invention in detail, the following will provide a specific description of the end cover plate 10 of the motor rotor, the motor rotor and the motor provided by the present invention.

[0033] Firstly, such as Figures 1 to 5As shown, this utility model provides an end cover plate 10 for a motor rotor, including a plate body and an oil return channel disposed within the plate body. The plate body has an inner end face 101 facing the rotor core 20 and an outer end face 102 away from the rotor core 20.

[0034] The oil return channel has an oil receiving opening and an oil return opening. The oil receiving opening is used to receive the cooling oil flowing out of the rotor core cooling oil channel; the oil return opening is used to guide the cooling oil back to the rotor core. Through the oil return channel, the cooling oil discharged from the rotor core cooling oil channel can be guided back to the rotor core, especially the rotor end face. The cooling oil has fluidity and can flow on the rotor end face, thus contacting the magnets at the rotor end face and directly cooling them.

[0035] The return oil channel can take many forms, as long as it can guide the cooling oil back to the rotor core end face. In some embodiments, the return oil channel is a return oil groove set on the inner end face. The opening of the return oil groove includes an oil receiving opening and an oil returning opening. The cooling oil flowing out of the rotor core cooling oil channel directly hits the return oil groove and then returns from the return oil groove back to the rotor core end plate. In other words, the return oil groove is both an oil receiving opening, an oil returning opening, and a return oil channel.

[0036] The plate has at least one oil return groove 103 recessed from the inner end face 101 towards the outer end face 102 along the circumferential direction. An oil drain channel 104 for draining oil is provided on the plate, and the oil return channel communicates with the outside of the motor rotor through the oil drain channel 104. The oil drain channel 104 penetrates the plate, meaning one end of the oil drain channel 104 communicates with the oil return groove 103, and the other end of the oil drain channel 104 communicates with the outside of the motor rotor.

[0037] like Figure 6 As shown, the rotor core 20 has multiple magnetic slots 201 arranged circumferentially. Along the axial direction of the rotor core, the oil return groove 103 overlaps with each magnetic slot 201 on the motor rotor core 20. This overlap can be partial, meaning the oil return groove 103 is smaller than the outline of the entire magnetic slot 201, or some other form of partial overlap. It can also be complete, meaning the outline of the oil return groove 103 is equal to or smaller than the outline of the magnetic slot 201, as long as a portion of the oil return groove 103 overlaps with the magnetic slot 201. Whether it's partial or complete overlap, as long as the oil return groove 103 overlaps with the magnetic slot 201 along the axial direction of the rotor core, it's acceptable.

[0038] Specifically, the oil return groove 103 is connected to the cooling oil channel of the rotor core. Therefore, when the cooling oil enters the oil return groove 103, the oil return groove 103 forms an oil storage tank. The cooling oil in the oil return groove 103 directly contacts the magnet at the end of the rotor core, exchanges heat with the magnet, and then is thrown out, instead of the coolant flowing out from the cooling oil channel of the rotor core 20 and being directly thrown out.

[0039] In some embodiments, the oil return groove 103 is an annular groove along the circumference of the plate, meaning that when cooling oil enters the oil return groove 103, the cooling oil is connected circumferentially within the plate. Part of the cooling oil is directly ejected from the plate through the drain channel 104, while some cooling oil flows circumferentially under centrifugal force, extending the flow path of some cooling oil, which is beneficial for cooling oil circulation, increases the interaction time between the cooling oil and the rotor core 20, and improves cooling efficiency. The circumferentially connected annular oil return groove 103 also allows cooling oil flowing from different cooling oil channels to exchange heat, resulting in a more uniform cooling oil temperature and better heat dissipation at the ends of the rotor core 20.

[0040] The two sides of the annular oil return groove 103 can be smooth. The shape of the oil return groove 103 can also be as follows: Figure 1 As shown, the outline of the oil return groove 103 is similar to that of the magnet groove 201. Multiple oil return grooves 103 can be provided on the inner end face 101. Discontinuous notches are provided on both sides of the oil return groove 103 to connect adjacent oil return grooves 103 and form a complete oil return groove 103. The similarity between the outline of the oil return groove 103 and the outline of the magnet groove 201 can further fix the magnets in the rotor core.

[0041] In some implementations, such as Figure 2 As shown, multiple oil return grooves 103 are arranged along the circumference of the plate. The number of oil return grooves 103 corresponds to the number of magnet slots 201, that is, the number of magnet slots 201 arranged on the rotor core 20 is the same as the number of oil return grooves 103 arranged on the plate.

[0042] like Figures 2 to 4As shown, each oil return groove 103 forms an independent cavity. The oil return grooves 103 are separated from each other by partition structures, ensuring that the cooling oil flow and heat exchange processes within each groove are independent and avoid mutual interference. This allows for more precise cooling of the magnets in each magnet slot 201. The contour of each oil return groove 103 matches the contour of the magnet slot 201. On one hand, when cooling oil is discharged from the cooling oil channel of the rotor core 20 and impacts the oil return groove 103, due to the contour fit, the cooling oil can surround the magnets in each magnet slot 201 in an all-round and tight manner, greatly enhancing the heat exchange efficiency between the cooling oil and the magnets. This achieves more efficient and comprehensive cooling of the magnets, effectively reducing the temperature of the magnets during motor operation and ensuring stable performance. On the other hand, the partition structures between the oil return grooves 103 increase the contact area between the end cover plate 10 and the rotor core 20. During the assembly and operation of the motor, the end cover plate 10, with its increased contact area, can more evenly and effectively press the rotor core 20, enhancing the stability of the overall rotor structure. When the motor rotates at high speed or is subjected to complex operating conditions, it ensures that the rotor core 20 and the end cover plate 10 always maintain a tight and stable connection, reducing the risk of component loosening or displacement caused by factors such as vibration and centrifugal force, and further improving the reliability and safety of motor operation.

[0043] In some embodiments, the cooling oil channel of the rotor core 20 is located between the outer wall of the rotating shaft and the shaft hole of the rotor core, or a separate cooling oil channel is provided on the rotor core 20. Therefore, a channel can be provided on the inner end face 101 of the end cover plate 10 to connect the oil return groove 103 with the shaft hole or cooling oil channel of the end cover plate.

[0044] In some embodiments, the magnet slot 201 is one of the cooling oil channels of the rotor core 20. The cooling oil flowing out of the magnet slot 201 directly impacts the oil return groove 103, and there is no need to add an additional channel to connect the oil return groove 103 and the magnet slot 201.

[0045] In some embodiments, each oil return groove 103 is provided with a protrusion 105 for guiding flow, and each oil return groove 103 has at least one protrusion 105 for changing the flow direction of cooling oil, such as... Figure 3 and Figure 4 As shown, the protrusion 105 extends along the rotor core axial direction from the inner end face 101 toward the side away from the outer end face 102. The shape of the protrusion 105 can be varied, such as cylindrical, conical, cuboid, etc. The number, shape, and size of the protrusions 105 in each oil return groove 103 can be the same or different.

[0046] The heat transfer coefficient of the cooling oil can be optimized by the protrusions 105. The protrusions 105 within the oil return groove 103 improve the flow path of the cooling oil. The rotation of the rotor core 20 causes the cooling oil within the oil return groove 103 to move along with it, and the protrusions 105 further disrupt the oil flow. The originally regular laminar flow is broken by the protrusions 105, forming turbulent flow. This turbulence increases the contact area between the cooling oil and the wall of the oil return groove 103, as well as the magnets, accelerating heat transfer and allowing the cooling oil to absorb the heat dissipated by the magnets more efficiently, thus improving cooling efficiency.

[0047] As the rotor core 20 rotates, cooling oil at different temperatures flows within the oil return groove 103. The protrusion 105 promotes the mixing of cooling oil at different temperatures, preventing localized overheating or undercooling. This mixing results in a more uniform temperature distribution of the cooling oil, ensuring that all parts of the magnet are cooled evenly, reducing performance differences in the magnet caused by uneven temperature, and improving the stability of motor operation.

[0048] The centrifugal force of the rotor core 20 provides additional flow force to the cooling oil. Under the action of centrifugal force, the cooling oil flows towards the edge of the oil return groove 103, while the protrusion 105 changes the direction of oil flow, enabling more efficient and comprehensive cooling of the magnets, reducing the temperature of the magnets during motor operation, and maintaining their performance stability. During the rotation of the rotor core 20, the cooling oil, under the combined action of centrifugal force and the protrusion 105, can more comprehensively cover the surface of the magnets, expanding the cooling range and ensuring that all parts of the magnets are effectively cooled.

[0049] Along the axial direction of the rotor core, the height of the protrusion 105 is lower than or equal to the height of the oil return groove 103. The inner end face 101 of the end cover plate 10, except for the oil return groove 103, is in contact with the rotor core 20. To avoid affecting the fit between the end cover plate 10 and the rotor core 20, the height of the protrusion 105 is lower than or equal to the height of the oil return groove 103. When the height of the protrusion 105 is equal to the height of the oil return groove 103, the protrusion 105 also contacts the rotor core 20 when the end cover plate 10 is in contact with it.

[0050] In some embodiments, cooling oil flows within the magnet groove 201, directly cooling the magnet. If the height of the protrusion 105 is lower than the height of the oil return groove 103, some cooling oil may impact the top of the protrusion 105 and then flow back onto the magnet. This changes the direction of the cooling oil, allowing it to flow back and cover the magnet surface. The returning cooling oil creates turbulence on the magnet surface, increasing the heat exchange coefficient between the cooling oil and the magnet. This more effectively removes the heat generated by the magnet, thereby enhancing the cooling effect and reducing the magnet temperature. The backflow phenomenon after impacting the top of the protrusion 105 prolongs the residence time of the cooling oil within the magnet groove 201, facilitating heat exchange between the cooling oil and the magnet. This allows the oil to absorb more heat per unit time, improving the utilization rate of the cooling oil and thus enhancing the overall cooling efficiency of the cooling system.

[0051] The plate is provided with an oil drain channel 104 to drain the cooling oil. In some embodiments, the oil drain channel 104 is directly set in the oil return groove 103. The oil drain channel 104 is a through hole formed from the inner end face 101 of the oil return groove 103 to the outer end face 102. Figure 4 and Figure 5 As shown, one end of the through hole is connected to the oil return groove 103, and the other end of the through hole is located on the outer end face 102. Multiple through holes can be provided in each oil return groove 103, and the multiple through holes can be arranged in parallel.

[0052] In some embodiments, the through hole is an oblique hole, such as... Figure 5 As shown, the through hole is radially outward from the inner end face 101 towards the outer end face 102, meaning the extension line of the inclined direction of the through hole intersects the axial direction of the rotor core. The inclined through hole allows the cooling oil to obtain a radially outward velocity component when flowing out. While the end cover plate 10 rotates and generates centrifugal force, the inclined through hole can further and quickly throw the cooling oil onto the motor stator. The end of the through hole away from the oil return groove 103 can also be set on the outer circumferential surface of the plate.

[0053] In some embodiments, the oil drain channel 104 is disposed on the outer circumferential surface of the plate, for example, it can be a notch disposed on the outer circumferential surface. Figure 1 and Figure 2 As shown, the notch can be semi-circular, U-shaped, or other shapes. Alternatively, an oil drain hole can be provided on the outer circumference, such as... Figure 3 As shown, the oil drain hole is located on the side wall of the oil return groove 103, thus eliminating the need for an additional channel to connect the oil return groove 103 to the oil drain hole. Multiple oil drain holes can be provided on the side wall of each oil return groove 103, and the oil drain holes can be circular, square, or other shapes.

[0054] Secondly, this utility model provides a motor rotor, including the aforementioned end cover plate 10, rotor core 20, and shaft. Both the end cover plate 10 and rotor core 20 are sleeved on the shaft. The end cover plate 10 is located on the end of the rotor core 20 and can be disposed at one or both ends of the rotor core 20. The oil return channel is connected to the cooling oil channel of the rotor core 20. Cooling oil in the shaft enters the rotor core 20 and then flows out from the end of the rotor core 20 into the oil return channel, where the cooling oil cools the magnets.

[0055] In some embodiments, the cooling oil channel of the rotor core 20 is the magnet slot 201 of the rotor core 20, and the oil return channel is the oil return groove 103. The outline of each oil return groove 103 is consistent with the outline of the magnet slot of the motor rotor, which can further fix the magnet in each magnet slot. If each magnet slot corresponds to an independent oil return groove 103, then each oil return groove 103 is respectively set as the outlet of the cooling oil channel of each rotor core; or the end cover plate 10 can be rotated relative to the rotor core at a certain angle so that the oil return groove 103 and the magnet slot 201 overlap at least partially, so that the cooling oil is thrown out from the magnet slots 201 on both sides of the rotor core 20 and directly impacts the oil return groove 103 of the end cover plate 10. The cooling oil in the oil return groove 103 can directly contact the magnet at the end of the rotor core 20 and perform heat exchange at the end of the rotor core 20.

[0056] The protrusion 105 is provided in the oil return groove 103, which can change the flow direction of the medium in the cavity and improve the heat transfer coefficient between the cooling oil and the end cover plate 10 and the end face of the rotor core 20.

[0057] Secondly, this utility model provides an electric motor, including the end cover plate of the motor rotor or the motor rotor described above.

[0058] The above embodiments are merely illustrative of the principles and effects of this utility model and are not intended to limit the scope of this utility model. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of this utility model. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in this utility model should still be covered by the claims of this utility model.

Claims

1. An end plate for a rotor of an electric machine, characterized in that include: The plate has an inner end face for contacting the end face of the rotor core; An oil return channel is provided in the plate body; the oil return channel has an oil receiving opening and an oil return opening, the oil receiving opening is used to receive cooling oil flowing out from the outlet of the rotor core cooling oil channel; the oil return opening is used to guide the cooling oil back to the rotor core; An oil drain channel, wherein the oil return channel is connected to the outside of the motor rotor through the oil drain channel; Both the oil receiving opening and the oil return opening are located on the inner end face.

2. The end plate of the electric machine rotor according to claim 1, characterized in that The oil return channel is an oil return groove provided on the inner end face, and the opening of the oil return groove includes the oil receiving opening and the oil return opening.

3. The end plate of the electric machine rotor according to claim 2, characterized in that Each of the oil return grooves is provided with at least one protrusion for guiding flow, the protrusion extending along the rotor core axial direction from the inner end face toward the side away from the outer end face.

4. The end plate of a rotor of an electrical machine according to any one of claims 1-3, characterized in that The oil drain channel is arranged along the thickness direction of the plate, one end of the oil drain channel is an oil drain opening, and the other end of the oil drain channel is connected to the oil return channel.

5. The end plate of the electric machine rotor according to claim 4, characterized in that The plate also has an outer end face that is opposite to the inner end face, the oil drain channel is a through hole that extends from the inner end face toward the outer end face, and the oil drain opening is located on the outer end face.

6. An end plate for an electric motor rotor as claimed in claim 5, characterised in that The through hole is an oblique hole, and the through hole is inclined outward along the radial direction of the plate from the inner end face to the outer end face.

7. The end plate of the electric machine rotor according to claim 4, characterized in that The oil drain opening is located on the outer circumferential surface of the plate.

8. An end plate for an electric motor rotor as claimed in claim 7, characterised in that The oil drain opening is an oil drain notch or oil drain hole.

9. An electric machine rotor, characterized in that The device includes an end cover plate, a rotor core, and a rotating shaft as described in any one of claims 1-8, wherein the end cover plate and the rotor core are both sleeved on the rotating shaft, and the end cover plate is located on the end of the rotor core; the oil return channel is connected to the cooling oil channel of the rotor core.

10. The electric machine rotor of claim 9, wherein, The oil return channel is an oil return groove, and the outline of each oil return groove is consistent with the outline of the magnet slot of the motor rotor.

11. The electrical machine rotor according to claim 9 or 10, characterized in that The plate has a plurality of oil return grooves along the circumferential direction, and each of the oil return grooves corresponds to the outlet of the cooling oil channel of each rotor core.

12. An electric machine characterized by It includes the end cover plate of the motor rotor as described in any one of claims 1-8, or the motor rotor as described in any one of claims 9-11.

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