Oil-cooled motor rotor and oil-cooled motor

Abstract

An oil-cooled motor rotor and an oil-cooled motor are provided. The oil-cooled motor rotor comprises multiple stacks, each stack comprising multiple rotor laminations. At least one stack includes a large-diameter rotor lamination, a small-diameter rotor lamination, and a sealing rotor lamination. The outer diameter of the small-diameter rotor lamination is smaller than that of the large-diameter rotor lamination, and when stacked together, they form a step at the outer periphery of the stack. The outer diameter of the sealing rotor lamination is equal to that of the large-diameter rotor lamination. The sealing rotor lamination includes a body portion and a rotor lamination sealing ring extending axially from the outer periphery of the body portion. The rotor lamination sealing ring of the first stack covers the radially outer side of the small-diameter rotor lamination of the adjacent second stack, thereby shielding any gaps that may exist between the first and second stacks from the radially outer side, reducing leakage of cooling oil from said gap.

Description

Technical Field

[0001] This application relates to the field of motor technology, and particularly to oil-cooled motor rotors and oil-cooled motors. Background Technology

[0002] The rotor of a permanent magnet synchronous motor typically consists of several stacked bodies. Each stacked body comprises several self-adhesive or ordinary laminations, which are stacked and impregnated with adhesive. The rotor laminations in each stacked body are tightly bonded together, with no gaps between them. However, due to manufacturing errors, small gaps will exist between the stacked bodies and between the stacked bodies and the balance plates on both sides of the axis.

[0003] To reduce the grade of the magnets and lower costs, pressurized active cooling oil can be introduced into the rotor magnet slots via a balance plate or rotor shaft on one axial side to directly cool the magnets in the slots. The oil then flows back to the oil pan through an oil outlet on the balance plate on the other axial side or through the rotor shaft. For example, WO2023 / 035022A1 discloses such a technology.

[0004] Carbon fiber sleeves can be added to the outside of the stack. The sleeves not only reinforce the rotor but also prevent pressurized oil entering the rotor magnet slots from leaking out through the small gaps between the stacks. For example, WO2024 / 099707A1 discloses such a technique.

[0005] However, this sleeve increases the air gap between the rotor and stator, thus affecting motor performance.

[0006] If no sleeve is added to the outside of the rotor, due to the pressure of the active cooling oil, the oil entering the magnet slot will be sprayed into the air gap between the rotor and stator through the small gaps between the stacked bodies and between the stacked bodies and the balance plate under oil pressure. Figure 6 The display shows the state of the rotor during high-speed testing. Oil spraying outward from the rotor generates noise and increases power loss. Utility Model Content

[0007] This application is made in view of the aforementioned state of the prior art. The purpose of this application is to provide an oil-cooled motor rotor and an oil-cooled motor that can reduce cooling oil leakage.

[0008] Embodiments of this application provide an oil-cooled motor rotor comprising multiple stacked bodies, each stacked body comprising multiple rotor laminations, and at least one stacked body comprising a large-diameter rotor lamination, a small-diameter rotor lamination, and a sealed rotor lamination.

[0009] The outer diameter of the smaller diameter rotor lamination is smaller than that of the larger diameter rotor lamination. When the two are stacked together, a step is formed on the outer periphery of the stack. The outer diameter of the sealing rotor lamination is equal to that of the larger diameter rotor lamination. The sealing rotor lamination includes a main body and a rotor lamination sealing ring extending axially from the outer periphery of the main body. The rotor lamination sealing ring of the first stack covers the radially outer side of the smaller diameter rotor lamination of the adjacent second stack, thereby blocking any gap that may exist between the first stack and the second stack from the radially outer side and reducing the leakage of cooling oil from the gap.

[0010] In at least one embodiment, the oil-cooled motor rotor further includes a first balance plate, the first balance plate including a balance plate body and a balance plate sealing portion extending axially from the outer periphery of the balance plate body to one side, the balance plate sealing portion covering the radially outer side of the small-diameter rotor laminations of adjacent stacks, thereby shielding any gaps that may exist between the first balance plate and the adjacent stacks from the radially outer side, reducing leakage of cooling oil from the gaps.

[0011] In at least one embodiment, the oil-cooled motor rotor further includes a second balance plate having a small diameter portion, thereby having an L-shaped stepped outer peripheral surface in axial cross section. The rotor lamination sealing ring of the stack adjacent to the second balance plate covers the radially outer side of the small diameter portion, thereby shielding any gap that may exist between the second balance plate and the adjacent stack from the radially outer side, reducing the leakage of cooling oil from the gap.

[0012] In at least one embodiment, the plurality of stacked bodies have identical structures, with the small-diameter rotor laminations and the sealed rotor laminations respectively disposed on both axial sides of the large-diameter rotor laminations.

[0013] Each of the stacks has a plurality of large-diameter rotor laminations, a plurality of small-diameter rotor laminations, and a sealing rotor lamination, wherein the axial dimension of the rotor lamination sealing ring is equal to the axial thickness of the plurality of small-diameter rotor laminations.

[0014] In at least one embodiment, each of the stacks has a plurality of large-diameter rotor laminations, a plurality of small-diameter rotor laminations, and a sealing rotor lamination, wherein the rotor lamination sealing ring is in transition fit with the outer periphery of the plurality of small-diameter rotor laminations.

[0015] In at least one embodiment, the sealed rotor laminations are integrally stamped silicon steel sheets.

[0016] In at least one embodiment, each of the stacks has a plurality of the large-diameter rotor laminations and a plurality of the small-diameter rotor laminations.

[0017] The axial dimension of the balance plate sealing part is equal to the axial thickness of the plurality of small-diameter rotor laminations, and / or the balance plate sealing part transitions with the outer periphery of the plurality of small-diameter rotor laminations.

[0018] In at least one embodiment, each of the stacks has a plurality of large-diameter rotor laminations, a plurality of small-diameter rotor laminations, and a sealed rotor lamination.

[0019] The axial dimension of the rotor lamination sealing ring is equal to the axial thickness of the small diameter portion of the second balance plate, and / or the rotor lamination sealing ring transitions with the outer periphery of the small diameter portion of the second balance plate.

[0020] In at least one embodiment, the stack has a plurality of first axial cooling oil channels and a plurality of second axial cooling oil channels axially extending through the stack, the second axial cooling oil channels being located radially outside the first axial cooling oil channels, and a balance plate oil channel being formed on the side of the first balance plate facing the stack for supplying oil to the first axial cooling oil channels and the second axial cooling oil channels.

[0021] The oil-cooled motor rotor also includes a motor shaft mounted on the radially inner side of the plurality of stacked bodies, the motor shaft having an oil supply hole communicating with the oil passage of the balance plate.

[0022] Embodiments of this application also provide an oil-cooled motor, which includes an oil-cooled motor rotor according to this application, and the oil-cooled motor further includes a stator located radially outside the oil-cooled motor rotor.

[0023] In the above scheme, the rotor lamination sealing ring of the first stack covers the radial outer side of the small-diameter rotor lamination of the adjacent second stack, thereby forming a seal for the gap that may exist between the two adjacent stacks. This can maintain the cooling oil pressure of the oil-cooled motor rotor and prevent or reduce the pressure oil in the cooling oil passage of the oil-cooled motor rotor from being sprayed radially outward between the stacks into the air gap between the rotor and stator, which can improve the efficiency and NVH performance of the motor. Attached Figure Description

[0024] Figure 1A This is an axial sectional view of an oil-cooled motor rotor according to one embodiment of this application.

[0025] Figure 1B yes Figure 1A A magnified view of a portion of the image.

[0026] Figure 2 yes Figure 1A An exploded view of a stack of oil-cooled motor rotors.

[0027] Figure 3A yes Figure 1A An exploded view of the rotor of an oil-cooled motor.

[0028] Figure 3B yes Figure 1A Another exploded view of the oil-cooled motor rotor.

[0029] Figure 4A yes Figure 2 A front view of the large-diameter rotor laminations of the oil-cooled motor rotor stack.

[0030] Figure 4B yes Figure 2 A front view of the small-diameter rotor laminations of the stacked body of the oil-cooled motor rotor.

[0031] Figure 4C yes Figure 2 A front view of the sealed rotor laminations of the stacked body of the oil-cooled motor rotor.

[0032] Figure 5A yes Figure 1A A slanted perspective view of the first balance plate of the oil-cooled motor rotor.

[0033] Figure 5B yes Figure 1A A slanted perspective view of the second balance plate of the oil-cooled motor rotor.

[0034] Figure 6 The status during the high-speed rotor test is displayed. Detailed Implementation

[0035] Exemplary embodiments of this application are described below with reference to the accompanying drawings. It should be understood that these specific descriptions are for teaching those skilled in the art how to implement this application only, and are not intended to exhaustively describe all possible methods of this application, nor to limit the scope of this application.

[0036] In this application, the axial direction refers to the axial direction A of the oil-cooled motor / motor shaft 3, and the radial direction refers to the radial direction R of the oil-cooled motor. The inner radial direction refers to the side of the radial direction R that is closer to the central axis of the motor shaft 3, and the outer radial direction refers to the side of the radial direction R that is farther away from the central axis of the motor shaft 3.

[0037] See Figures 1A to 5B This application provides an oil-cooled motor rotor, comprising a plurality of stacked bodies 11, each stacked body 11 including a plurality of rotor laminations. The plurality of stacked bodies 11 are stacked together to form a rotor core 1. See also Figure 1A , Figure 1B and Figure 2 At least one stack 11 includes a large-diameter rotor lamination 111, a small-diameter rotor lamination 113, and a sealed rotor lamination 112.

[0038] The outer diameter of the smaller diameter rotor lamination 113 is smaller than that of the larger diameter rotor lamination 111, and when they are stacked together, a step is formed at the outer periphery of the stack. The outer diameter of the sealing rotor lamination 112 is equal to that of the larger diameter rotor lamination 111. The sealing rotor lamination 112 includes a main body 1121 and a rotor lamination sealing ring 1122 extending axially from the outer periphery of the main body 1121. The rotor lamination sealing ring 1122 of the first stack covers the radially outer side of the smaller diameter rotor lamination 113 of the adjacent second stack, thereby blocking any gap that may exist between the first and second stacks from the radially outer side and reducing the leakage of cooling oil from this gap.

[0039] It is understandable that the gap that may exist between the first and second stacks is often caused by the fact that the surfaces of the stacks cannot be perfectly flat in practice, and the location of the gap cannot be completely determined.

[0040] by Figure 1A , Figure 1B The example shown illustrates that the rotor of the oil-cooled motor can have six stacks 11. The rotor lamination sealing ring 1122 of the first left-hand stack 11 covers the radially outer side of the small-diameter rotor laminations 113 of the second left-hand stack 11. In this fit, the first left-hand stack 11 can be referred to as the first stack, and the second left-hand stack 11 can be referred to as the second stack.

[0041] The rotor lamination sealing ring 1122 of the second stack 11 from the left covers the radial outer side of the small-diameter rotor lamination 113 of the third stack 11 from the left. In this fit, the second stack 11 from the left can be referred to as the first stack, and the third stack 11 from the left can be referred to as the second stack.

[0042] In the above scheme, the rotor lamination sealing ring 1122 of the first stack body covers the radial outer side of the small-diameter rotor lamination 113 of the adjacent second stack body, thereby forming a seal for the gap that may exist between the two adjacent stack bodies 11. This can maintain the cooling oil pressure of the oil-cooled motor rotor, prevent or reduce the pressure oil in the cooling oil passage of the oil-cooled motor rotor from being sprayed radially outward between the stack bodies 11 into the air gap between the rotor and the stator, and improve the efficiency and NVH performance of the motor.

[0043] It is not necessary to install a sleeve made of materials such as carbon fiber on the outer periphery of the rotor, which can ensure a small air gap and will not adversely affect the motor performance.

[0044] The oil-cooled motor rotor structure described above is simple, easy to manufacture, and has reliable sealing.

[0045] Optionally, see Figure 1A , Figure 1B and Figure 5AThe oil-cooled motor rotor may also include a first balancing plate 21. The first balancing plate 21 may include a balancing plate body 211 and a balancing plate sealing portion 212 extending axially from the outer periphery of the balancing plate body 211. The balancing plate sealing portion 212 covers the radially outer side of the small-diameter rotor laminations 113 of the adjacent stack 11, thereby blocking any gap that may exist between the first balancing plate 21 and the adjacent stack 11 from the radially outer side, reducing the leakage of cooling oil from the gap.

[0046] This maintains the cooling oil pressure of the oil-cooled motor rotor, preventing or reducing the spraying of pressure oil from the oil-cooled motor rotor radially outward between the first balance plate 21 and the stack 11 (rotor core 1), thereby improving the motor's efficiency and NVH performance.

[0047] Optionally, see Figure 1A , Figure 1B and Figure 5B The oil-cooled motor rotor also includes a second balance plate 22, which has a small diameter portion 221, so that the second balance plate 22 has an L-shaped stepped outer peripheral surface in axial section. The rotor lamination sealing ring 1122 of the stack body 11 adjacent to the second balance plate 22 covers the radial outer side of the small diameter portion 221, thereby blocking the gap that may exist between the second balance plate 22 and the adjacent stack body 11 from the radial outer side, reducing the leakage of cooling oil from the gap.

[0048] This maintains the cooling oil pressure of the oil-cooled motor rotor, preventing or reducing the spraying of pressure oil from the oil-cooled motor rotor radially outward between the second balance plate 22 and the stack 11 (rotor core 1), thereby improving the motor's efficiency and NVH performance.

[0049] It is understandable that, on the outer periphery, the two balance plates can have the following characteristics: Figure 1A and Figure 1B The different structures shown.

[0050] Alternatively, the two balance plates can have a similar structure on the outer periphery. For example, when both balance plates have balance plate sealing portions 212, the two stacked bodies 11 on both axial sides have small-diameter rotor laminations 113 on each axial side; when both balance plates have small-diameter portions 221, the two stacked bodies 11 on both axial sides have sealing rotor laminations 112 on each axial side. It is sufficient to form a seal between the balance plate and the adjacent stacked bodies 11.

[0051] Optionally, see Figures 1A to 3BThe multiple stacks 11 can have identical structures, with small-diameter rotor laminations 113 and sealing rotor laminations 112 respectively disposed on both axial sides of the large-diameter rotor laminations 111. Each stack 11 can have multiple large-diameter rotor laminations 111, multiple small-diameter rotor laminations 113, and one sealing rotor lamination 112. The axial dimension of the rotor lamination sealing ring 1122 is equal to the axial thickness of the multiple small-diameter rotor laminations 113. In this way, the rotor lamination sealing ring 1122 of the sealing rotor lamination 112 of the first stack can axially abut against the large-diameter rotor lamination 111 of the adjacent second stack, thereby improving the sealing performance.

[0052] Having multiple stacked bodies 11 with identical structures can reduce the variety of components and facilitate the production and assembly of oil-cooled motor rotors.

[0053] In another example, there may be, for example, two types of stacked bodies 11. In one type of stacked body 11, sealed rotor laminations 112 are respectively provided on both sides of the large-diameter rotor laminations 111, and in another type of stacked body 11, small-diameter rotor laminations 113 are respectively provided on both sides of the large-diameter rotor laminations 111. The one type of stacked body 11 and the other type of stacked body 11 can be arranged alternately in the axial direction A.

[0054] Optionally, the rotor lamination sealing ring 1122 transitionally engages with the outer periphery of the plurality of small-diameter rotor laminations 113. This facilitates assembly between adjacent stacks while ensuring proper sealing.

[0055] Optionally, the sealing rotor laminations 112 are integrally stamped silicon steel sheets. This facilitates production, reduces costs, and ensures good sealing performance.

[0056] Optionally, the axial dimension of the balance plate sealing part 212 is equal to the axial thickness of the plurality of small-diameter rotor laminations 113. This ensures a certain axial coverage dimension, and the balance plate sealing part 212 can axially abut against the large-diameter rotor laminations 111 of the adjacent stack 11, thereby improving the sealing performance.

[0057] Optionally, the balance plate seal 212 transitionally engages with the outer periphery of the plurality of small-diameter rotor laminations 113. This facilitates assembly between the first balance plate 21 and adjacent stacks 11 while ensuring proper sealing.

[0058] Optionally, each stack 11 has multiple large-diameter rotor laminations 111, multiple small-diameter rotor laminations 113, and a sealing rotor lamination 112. The axial dimension of the rotor lamination sealing ring 1122 is equal to the axial thickness of the small-diameter portion 221 of the second balance plate 22. This improves the sealing performance.

[0059] Optionally, the rotor lamination sealing ring 1122 transitions into the outer periphery of the small-diameter portion 221 of the second balance plate 22. This facilitates the assembly of the second balance plate 22 with the adjacent stack 11 while ensuring proper sealing.

[0060] Optionally, see Figure 1A , Figure 1B , Figure 2 and Figure 5A The stack 11 has a plurality of first axial cooling oil channels 114 and a plurality of second axial cooling oil channels 115 axially extending through the stack 11, the second axial cooling oil channels 115 being located radially outside the first axial cooling oil channels 114. The side of the first balance plate 21 facing the stack 11 may form a balance plate oil channel 213 for supplying oil to the first axial cooling oil channels 114 and the second axial cooling oil channels 115.

[0061] The oil-cooled motor rotor may also include a motor shaft 3 mounted radially inside the plurality of stacked bodies 11, the motor shaft 3 having an oil supply hole 31 communicating with the oil passage 213 of the balance plate. Here, the motor shaft 3 may be a hollow shaft, or the interior of the motor shaft 3 may form a cooling oil chamber.

[0062] In this way, cooling channels can be easily formed for the motor shaft 3, the first balance plate 21, and the stack 11. The stack 11 forms multiple cooling oil channels at different radial positions, which can improve the cooling effect of the rotor.

[0063] like Figure 2 As shown, multiple axial cooling oil channels can be formed at the end of the magnet mounting slot of the rotor core 1.

[0064] like Figure 5B As shown, multiple oil outlet holes 222 and 223 can be formed on the second balance plate 22. Figure 1A and Figure 1B As shown, except for the chamfers at both ends of the axial direction, the outer circumferential surfaces of the oil-cooled motor rotor can be basically located on the same cylindrical surface. That is, the maximum outer diameter of the first balance plate 21 and the second balance plate 22, the outer diameter of the large-diameter rotor lamination 111, and the outer diameter of the sealed rotor lamination 112 can be equal.

[0065] Embodiments of this application also provide an oil-cooled motor, which includes an oil-cooled motor rotor according to this application. The oil-cooled motor may also include a stator located radially outside the oil-cooled motor rotor. The oil-cooled motor may be a permanent magnet synchronous motor.

[0066] Embodiments of this application also provide a vehicle drive system, which includes an oil-cooled motor rotor or an oil-cooled motor according to this application.

[0067] The motor described in this application can be used as a power unit in pure electric vehicles or hybrid vehicles.

[0068] It should be understood that at least some aspects or features of the above-described implementation methods, embodiments, or examples can be appropriately combined.

[0069] It is understood that, in this application, when the number of parts or components is not specifically limited, the number can be one or more, where multiple refers to two or more. For cases where the number of parts or components shown in the drawings and / or described in the specification is, for example, two, three, four, etc., this specific number is generally exemplary and not restrictive, and can be understood as multiple, i.e., two or more; however, this does not mean that this application excludes the case of one.

[0070] In this application, unless otherwise expressly stated or limited, terms such as "installation," "assembly," "connection," "linking," "joining," "linking," "abutment," "communication," "connection," "conduction," "fixing," and "fastening" should be interpreted broadly, for example, they can be direct or indirect. For instance, regarding connection, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be the internal communication of two components or the interaction between two components, unless otherwise expressly stated or limited. For instance, regarding communication / conduction, it can be direct communication / conduction or indirect communication / conduction through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0071] It should be understood that the above-described embodiments, examples, or examples are merely exemplary and are not intended to limit this application. Those skilled in the art can make various modifications and changes to the above-described embodiments, examples, or examples under the teachings of this application without departing from the scope of this application.

Claims

1. An oil-cooled motor rotor, comprising a plurality of stacked bodies, each of the stacked bodies comprising a plurality of rotor laminations, characterized in that, At least one of the stacked bodies includes a large-diameter rotor lamination, a small-diameter rotor lamination, and a sealed rotor lamination. The outer diameter of the smaller diameter rotor lamination is smaller than that of the larger diameter rotor lamination. When the two are stacked together, a step is formed on the outer periphery of the stack. The outer diameter of the sealing rotor lamination is equal to that of the larger diameter rotor lamination. The sealing rotor lamination includes a main body and a rotor lamination sealing ring extending axially from the outer periphery of the main body. The rotor lamination sealing ring of the first stack covers the radially outer side of the smaller diameter rotor lamination of the adjacent second stack, thereby blocking any gap that may exist between the first stack and the second stack from the radially outer side and reducing the leakage of cooling oil from the gap.

2. The oil-cooled motor rotor according to claim 1, characterized in that, The oil-cooled motor rotor also includes a first balance plate, which includes a balance plate body and a balance plate sealing portion extending axially from the outer periphery of the balance plate body. The balance plate sealing portion covers the radially outer side of the small-diameter rotor laminations of the adjacent stack, thereby shielding the gap that may exist between the first balance plate and the adjacent stack from the radially outer side and reducing the leakage of cooling oil from the gap.

3. The oil-cooled motor rotor according to claim 1 or 2, characterized in that, The oil-cooled motor rotor also includes a second balance plate, which has a small diameter portion, and thus the second balance plate has an L-shaped stepped outer peripheral surface in axial section. The rotor lamination sealing ring of the stack adjacent to the second balance plate covers the radially outer side of the small diameter portion, thereby blocking any gap that may exist between the second balance plate and the adjacent stack from the radially outer side, reducing the leakage of cooling oil from the gap.

4. The oil-cooled motor rotor according to claim 1 or 2, characterized in that, The multiple stacked bodies have the same structure, with the small-diameter rotor laminations and the sealed rotor laminations respectively disposed on both axial sides of the large-diameter rotor laminations. Each of the stacks has a plurality of large-diameter rotor laminations, a plurality of small-diameter rotor laminations, and a sealing rotor lamination, wherein the axial dimension of the rotor lamination sealing ring is equal to the axial thickness of the plurality of small-diameter rotor laminations.

5. The oil-cooled motor rotor according to claim 1 or 2, characterized in that, Each of the stacks has a plurality of large-diameter rotor laminations, a plurality of small-diameter rotor laminations, and a sealed rotor lamination, wherein the rotor lamination sealing ring is in transition fit with the outer periphery of the plurality of small-diameter rotor laminations.

6. The oil-cooled motor rotor according to claim 1 or 2, characterized in that, The sealed rotor laminations are integrally stamped silicon steel sheets.

7. The oil-cooled motor rotor according to claim 2, characterized in that, Each of the stacks has a plurality of large-diameter rotor laminations and a plurality of small-diameter rotor laminations. The axial dimension of the balance plate sealing part is equal to the axial thickness of the plurality of small-diameter rotor laminations, and / or the balance plate sealing part transitions with the outer periphery of the plurality of small-diameter rotor laminations.

8. The oil-cooled motor rotor according to claim 3, characterized in that, Each of the stacks has multiple large-diameter rotor laminations, multiple small-diameter rotor laminations, and a sealed rotor lamination. The axial dimension of the rotor lamination sealing ring is equal to the axial thickness of the small diameter portion of the second balance plate, and / or the rotor lamination sealing ring transitions with the outer periphery of the small diameter portion of the second balance plate.

9. The oil-cooled motor rotor according to claim 2, characterized in that, The stack has a plurality of first axial cooling oil channels and a plurality of second axial cooling oil channels that axially penetrate the stack. The second axial cooling oil channels are located radially outside the first axial cooling oil channels. The side of the first balance plate facing the stack forms a balance plate oil channel for supplying oil to the first axial cooling oil channels and the second axial cooling oil channels. The oil-cooled motor rotor also includes a motor shaft mounted on the radially inner side of the plurality of stacked bodies, the motor shaft having an oil supply hole communicating with the oil passage of the balance plate.

10. An oil-cooled motor, characterized in that, The oil-cooled motor includes the rotor of any one of claims 1 to 9, and the oil-cooled motor further includes a stator located radially outside the rotor of the oil-cooled motor.

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