A motor rotor assembly and a motor

Abstract

The application provides a motor rotor assembly and a motor, and the motor rotor assembly comprises a rotor core and a magnetic steel, the rotor core is provided with a magnetic steel slot, the magnetic steel can be arranged in the magnetic steel slot, and at least one slot section exists on the magnetic steel slot along an axial direction of the rotor core, which is a circumferential flow-through slot; the flow-through area ratio of the circumferential flow-through slot is larger than that of a partial slot section of the magnetic steel slot connected with the circumferential flow-through slot along the axial direction, that is, the area ratio of the circumferential flow-through slot is larger than that of the partial slot section of the magnetic steel slot connected with the circumferential flow-through slot along the axial direction in a projection plane of an axial end surface of the rotor core; and a gap exists between an inner wall of the circumferential flow-through slot and an outer periphery of the magnetic steel, so that gas can enter the circumferential flow-through slot to perform surrounding cooling on the magnetic steel. According to the application, effective cooling and heat dissipation of the magnetic steel can be realized, and the situation that the rotor is seriously heated is avoided; and the problem that the magnetic steel in the motor in the prior art cannot be effectively cooled and the problem that the heating is obvious are effectively solved.

Description

Technical Field

[0001] This invention relates to the field of motor technology, and more specifically to a motor rotor assembly and a motor. Background Technology

[0002] Cooling has always been a key and challenging issue in the design and development of high-speed motors, especially rotor cooling. During high-speed rotation, the rotor generates significant heat due to losses from wind wear and eddy currents. This heat is extremely difficult to dissipate internally, and inadequate cooling can lead to irreversible demagnetization, severely impacting motor performance. Therefore, ensuring adequate cooling of the magnets is a current challenge. Current technologies typically utilize the air gap between the stator and rotor, employing either a self-contained impeller to deliver air or radial ventilation through openings in the stator and housing. While the airflow carries away some heat from the rotor surface, this is insufficient and fails to effectively cool the internal magnets, thus failing to address the rotor temperature rise problem.

[0003] Patent KR101407948B1 discloses a method that cools the rotor to some extent by sending air into the motor through the outside of the housing and letting the air flow through the air gap between the stator and rotor. The compressed air entering the housing is relatively dispersed, resulting in a small effective cooling area for the rotor and poor cooling effect. Furthermore, it does not consider the cooling of the magnets and cannot solve the problem of rotor temperature rise.

[0004] Because existing motors suffer from problems such as insufficient and ineffective cooling of internal magnets, resulting in significant heat generation, this invention researches and designs a motor rotor assembly and a motor. Summary of the Invention

[0005] Therefore, the technical problem to be solved by the present invention is to overcome the defect in the prior art where the internal magnets of the motor cannot be effectively cooled, resulting in significant heat generation, thereby providing a motor rotor assembly and a motor.

[0006] To address the above problems, the present invention provides a motor rotor assembly comprising:

[0007] The rotor core comprises a rotor core and magnets. Magnet slots are formed on the rotor core, and magnets are disposed within these slots. Along the axial direction of the rotor core, at least one segment of the magnet slot is a circumferential flow groove. The flow area of ​​this circumferential flow groove is larger than the flow area of ​​a portion of the magnet slot connected to it along the axial direction. Specifically, within the projection plane of the axial end face of the rotor core, the area of ​​the circumferential flow groove is larger than the flow area of ​​a portion of the magnet slot connected to it along the axial direction. A gap exists between the inner wall of the circumferential flow groove and the outer periphery of the magnet, allowing gas to enter the circumferential flow groove for surrounding cooling of the magnet.

[0008] In some implementations...

[0009] The rotor core includes multiple rotor laminations stacked together along the axial direction of the rotor core. Each rotor lamination is provided with a magnetic slot unit. The magnetic slot units on the multiple rotor laminations are opposite to each other along the axial direction and are connected to form the magnetic slot. The multiple rotor laminations include at least one heat dissipation lamination. The magnetic slot unit on the heat dissipation lamination is the circumferential flow groove. In the projection plane of the axial end face of the rotor core, the area of ​​the circumferential flow groove of the heat dissipation lamination is larger than the area of ​​the magnetic slot unit on the rotor lamination axially adjacent to it.

[0010] In some implementations...

[0011] The circumferential flow groove on the heat dissipation fin extends beyond the magnetic groove unit on the axially adjacent rotor fin by a dimension in any direction, which is the groove depth of the circumferential flow groove, denoted as a, where a ranges from 0.1 to 0.5 mm; the heat dissipation fin consists of 1 to 2 fins stacked together, with 4 to 8 rotor fins on one axial side of the stacked heat dissipation fins and 4 to 8 rotor fins on the other axial side.

[0012] In some implementations...

[0013] Within the projection plane of the axial end face of the rotor core, the circumferential flow groove is a polygonal or curved structure, and there is a gap between each side of the polygon or any point on the curved structure and the outer periphery of the magnet, so as to form a surrounding cooling of the magnet through circumferential circulation.

[0014] In some implementations...

[0015] The inner circumferential wall of the magnet groove has at least one location that is spaced from the outer circumference of the magnet, forming an axial flow groove at the space. The axial flow groove passes through the rotor core along the axial direction and is connected to the circumferential flow groove.

[0016] In some implementations...

[0017] There are at least two axial flow grooves, at least one of which is located on one side of the magnet and at least one of which is located on the other side of the magnet. The one side of the magnet is opposite to the other side. The circumferential flow groove is located inside the rotor core, that is, the circumferential flow groove is spaced more than 0 from one axial end face of the rotor core, and the circumferential flow groove is also spaced more than 0 from the other axial end face of the rotor core.

[0018] In some implementations...

[0019] There are multiple magnetic steel slots, which are spaced apart in the circumferential direction of the rotor core. Each magnetic steel slot has at least one circumferential flow groove and at least one axial flow groove.

[0020] In some implementations...

[0021] The rotor core is also provided with an air duct outlet. One end of the air duct outlet is connected to the axial flow groove, and the other end extends through to the outer periphery of the rotor core.

[0022] In some implementations...

[0023] It also includes a rotor baffle, which is disposed at one axial end of the rotor core and has a hollow cavity inside. An air intake channel is provided on the outer peripheral wall of the rotor baffle extending toward the interior of the rotor baffle. One end of the air intake channel is located on the outer wall of the rotor baffle, and the other end of the air intake channel extends toward the interior of the rotor baffle to communicate with the hollow cavity. The air intake channel can introduce gas from the outside and guide it into the hollow cavity. The hollow cavity can communicate with the magnetic steel groove to introduce gas into the magnetic steel groove.

[0024] In some implementations...

[0025] The rotor baffle includes a first shaft segment and a second shaft segment. The first shaft segment and the second shaft segment are connected together along the axial direction of the rotor baffle. Both the first shaft segment and the second shaft segment are annular structures and have the same outer diameter. The inner diameter of the first shaft segment is larger than the inner diameter of the second shaft segment, so as to form the hollow cavity on the inner circumference of the first shaft segment.

[0026] In some implementations...

[0027] The second shaft segment includes a first axial end face, which is connected to the hollow cavity along the axial direction of the rotor baffle. The air intake channel is opposite to the first axial end face along the radial direction of the rotor baffle, such that the air intake channel passes through the outer peripheral wall of the rotor baffle into the interior of the rotor baffle, and a portion of the air intake channel is located on the first axial end face and faces and communicates with the hollow cavity.

[0028] In some implementations...

[0029] Within the projection plane of the axial end face of the rotor baffle, the direction from the inlet end to the outlet end of the air intake channel is opposite to the rotation direction of the rotor baffle; the flow area at the outlet end of the air intake channel is larger than the flow area at its inlet end; there are multiple air intake channels, and the multiple air intake channels are spaced apart in the circumferential direction of the rotor baffle.

[0030] In some implementations...

[0031] It also includes a first air guide channel and a second air guide channel. The first air guide channel is opened on the second axial end face of the rotor baffle facing the rotor core, and one end of the first air guide channel is connected to the hollow cavity. The second air guide channel is also opened on the second axial end face and is axially connected to the magnet slot. The other end of the first air guide channel is connected to the second air guide channel.

[0032] In some implementations...

[0033] The first air guide channel is a groove formed by recessing the second axial end face in a direction away from the rotor core. Along the radial direction of the rotor baffle, the radial inner end of the first air guide channel communicates with the hollow cavity, and the radial outer end of the first air guide channel communicates with the second air guide channel. The second air guide channel is a groove formed by recessing the second axial end face in a direction away from the rotor core. The second air guide channel is an annular groove. There are multiple first air guide channels, and the multiple first air guide channels are spaced apart in the circumferential direction of the rotor baffle and are all connected to the second air guide channel.

[0034] In some implementations...

[0035] The rotor baffle is also provided with an air outlet channel. One end of the air outlet channel is connected to the second air guide channel, and the other end extends to the outer peripheral wall of the rotor baffle so as to exhaust the gas to the outside of the rotor baffle.

[0036] In some implementations...

[0037] An angle θ is formed between the centerline of the inlet end face and the centerline of the outlet end face of the air intake channel, where θ satisfies the range 10°≤θ≤30°. The diameter of the inlet end of the air intake channel is d1, and the diameter of the outlet end is d2, with 1.2≤d2 / d1≤1.5.

[0038] Within the projection plane of the axial end face of the rotor baffle, along the circumferential direction of the rotor baffle, the circumferential width of the first air guide channel is b, the circumferential width of the air outlet channel is c, and 5≤b / c≤12.

[0039] The present invention also provides an electric motor, which includes the aforementioned motor rotor assembly.

[0040] The motor rotor assembly and motor provided by this invention have the following beneficial effects:

[0041] 1. This invention, by configuring at least one slot segment in the magnet slots of the rotor core as a circumferential flow groove, wherein the flow area of ​​the circumferential flow groove is larger than that of its adjacent slot segments (i.e., the area of ​​the circumferential flow groove in the projection plane of the axial end face is larger than the area of ​​the adjacent slot segments), allows gas to enter the circumferential flow groove to provide enveloping cooling of the magnets, enhances the airflow for cooling the magnets, achieves targeted and effective cooling and heat dissipation of the magnets, avoids the situation where the heat of the magnets inside the rotor is extremely difficult to dissipate, leading to severe rotor overheating, and prevents irreversible high-temperature demagnetization; effectively solving the problem in the prior art where the magnets inside the motor cannot be effectively cooled, resulting in significant overheating.

[0042] 2. This invention also appropriately enlarges the area of ​​the magnet slots in some rotor laminations to form circumferential flow slots for heat dissipation laminations. After multiple rotor laminations are stacked, an annular flow path for the permanent magnet is formed, achieving circumferential surrounding cooling of the permanent magnet. This invention eliminates the need for magnet processing and reduces the temperature of the internal magnets during high-speed rotor operation without affecting motor performance. It can effectively solve the problem of internal rotor temperature rise and further improve the rotor's anti-demagnetization capability. Attached Figure Description

[0043] Figure 1 This is a front view of the motor rotor assembly of the present invention.

[0044] Figure 2 yes Figure 1 A longitudinal section diagram of the right half of the structure;

[0045] Figure 3 This is an exploded view of the assembled motor rotor assembly of the present invention;

[0046] Figure 4 This is a partial enlarged view of the rotor core (magnetic slot) of the present invention;

[0047] Figure 5 yes Figure 4 A structural diagram of a single rotor lamination after magnets are installed on the rotor core;

[0048] Figure 6 This is a front structural view of the rotor baffle of the motor rotor assembly of the present invention;

[0049] Figure 7 yes Figure 6 A longitudinal section diagram of the rotor baffle at the intake passage;

[0050] Figure 8 This is a three-dimensional structural diagram of the rotor baffle of the present invention;

[0051] Figure 9 yes Figure 8 Side view structural diagram;

[0052] Figure 10 This is a top view of the rotor lamination (with an air duct outlet) of the present invention.

[0053] The reference numerals in the attached figures are as follows:

[0054] 1. Rotating shaft; 2. Rotor core; 3. Rotor baffle; 4. Heat dissipation fins; 5. Magnet; 6. Rotor laminations; 7. Magnet slot; 8. Hollow cavity; 9. First shaft section; 10. Second shaft section; 11. First axial end face; 12. Second axial end face; 2-1. Circumferential flow groove; 3-1. Air inlet channel; 3-1-1. Air duct inlet guide; 3-3. First air guide channel; 3-2. Second air guide channel; 3-4. Air outlet channel; 5-1. Axial flow groove; 6-1. Air duct outlet. Detailed Implementation

[0055] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the present invention or its application or use. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0056] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0057] Unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps set forth in these embodiments do not limit the scope of the invention. It should also be understood that, for ease of description, the dimensions of the various parts shown in the drawings are not drawn to actual scale. Techniques, methods, and devices known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of the specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters in the following figures denote similar items; therefore, once an item is defined in one figure, it need not be further discussed in subsequent figures.

[0058] In the description of this invention, it should be understood that the orientation or positional relationship indicated by directional terms such as "front, back, up, down, left, right", "horizontal, vertical, horizontal" and "top, bottom" is generally based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing this invention and simplifying the description. Unless otherwise stated, these directional terms do not indicate or imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the scope of protection of this invention; the directional terms "inner" and "outer" refer to the inner and outer contours relative to the outline of each component itself.

[0059] For ease of description, spatial relative terms such as "above," "on top of," "on the upper surface of," "above," etc., are used herein to describe the spatial positional relationship of a device or feature as shown in the figures to other devices or features. It should be understood that spatial relative terms are intended to encompass different orientations in use or operation beyond the orientation of the device as described in the figures. For example, if the device in the figures were inverted, a device described as "above" or "on top of" other devices or structures would subsequently be positioned as "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both "above" and "below." The device may also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used herein will be interpreted accordingly.

[0060] Furthermore, it should be noted that the use of terms such as "first" and "second" to define components is merely for the purpose of distinguishing the corresponding components. Unless otherwise stated, the above terms have no special meaning and therefore should not be construed as limiting the scope of protection of this invention.

[0061] like Figure 1-10As shown, the present invention provides a motor rotor assembly, which includes:

[0062] The rotor core 2 and magnet 5 are provided. The rotor core 2 has a magnet slot 7, and the magnet 5 can be disposed in the magnet slot 7. Along the axial direction of the rotor core 2, there is at least one slot segment on the magnet slot 7, which is a circumferential flow slot 2-1. The flow area of ​​the circumferential flow slot 2-1 is larger than the flow area of ​​a portion of the magnet slot 7 connected to it along the axial direction. That is, in the projection plane of the axial end face of the rotor core 2, the area of ​​the circumferential flow slot 2-1 is larger than the flow area of ​​a portion of the magnet slot 7 connected to it along the axial direction. There is a gap between the inner wall of the circumferential flow slot 2-1 and the outer periphery of the magnet 5, so that gas can enter the circumferential flow slot 2-1 to surround and cool the magnet 5.

[0063] This invention addresses the problem of ineffective cooling of the magnets in the rotor core by designating at least one slot as a circumferential flow groove. The circumferential flow groove has a larger flow area than its adjacent slots; that is, the area of ​​the circumferential flow groove in the projection plane of the axial end face is larger than that of the adjacent slots. This allows gas to enter the circumferential flow groove, providing enveloping cooling to the magnets. This enhances the airflow for cooling the magnets, achieving targeted and effective cooling and heat dissipation. It avoids the problem of severe rotor overheating due to the difficulty in dissipating heat from the magnets inside the rotor, and prevents irreversible high-temperature demagnetization. This effectively solves the problem in existing technologies where the magnets inside the motor cannot be effectively cooled, leading to significant overheating.

[0064] In some implementations...

[0065] The rotor core 2 includes a plurality of rotor laminations 6, which are stacked together along the axial direction of the rotor core 2. Each rotor lamination 6 is provided with a magnetic slot unit. The magnetic slot units on the plurality of rotor laminations 6 are opposite to each other along the axial direction and are connected to form the magnetic slot 7. The plurality of rotor laminations 6 include at least one heat dissipation lamination 4. The magnetic slot unit on the heat dissipation lamination 4 is the circumferential flow groove 2-1. In the projection plane of the axial end face of the rotor core 2, the area of ​​the circumferential flow groove 2-1 of the heat dissipation lamination 4 is larger than the area of ​​the magnetic slot unit on the rotor lamination 6 adjacent to it in the axial direction.

[0066] This invention also moderately enlarges the area of ​​the magnet slots in some rotor laminations to form circumferential flow slots for heat dissipation laminations. After multiple rotor laminations are stacked, an annular flow path for the permanent magnet is formed, achieving circumferential surrounding cooling of the permanent magnet. This invention eliminates the need for magnet processing and reduces the temperature of the internal magnets during high-speed rotor operation without affecting motor performance. It can effectively solve the problem of internal rotor temperature rise and further improve the rotor's anti-demagnetization capability.

[0067] In some implementations...

[0068] The circumferential flow groove 2-1 on the heat dissipation fin extends beyond the magnetic steel groove unit on the axially adjacent rotor fin 6 by a dimension in any direction, which is the groove depth of the circumferential flow groove 2-1, denoted as a, where a ranges from 0.1 to 0.5 mm. The heat dissipation fin consists of 1 to 2 fins stacked together, with 4 to 8 rotor fins on one axial side of the stacked heat dissipation fins and 4 to 8 rotor fins on the other axial side.

[0069] This is a preferred structural form of the circumferential flow groove of the present invention, wherein the groove depth 'a' ranges from 0.1 to 0.5 mm (preferably 0.2 mm), which can improve the effective cooling and heat dissipation performance of the magnets while ensuring the structural strength of the rotor laminations; for example Figure 4-5 As shown, the rotor core is formed by stacking rotor laminations one by one. During stacking, 4 to 8 normal-sized laminations (normal rotor laminations) are typically followed by 1 to 2 larger-sized laminations (i.e., heat dissipation laminations). After stacking, the core naturally forms... Figure 4 and Figure 2 The flow channel effect shown.

[0070] In some implementations...

[0071] Within the projection plane of the axial end face of the rotor core 2, the circumferential flow groove 2-1 is a polygonal or curved structure, and there is a gap between each side of the polygon or any point on the curved structure and the outer periphery of the magnet 5, so as to form a surrounding cooling of the circumferential circulation of the magnet 5.

[0072] This is the preferred structural form of the circumferential flow groove of the present invention. It is preferably a polygonal or curved structure, and any point on the polygonal or curved surface has a gap with the outer periphery of the magnet, thereby forming a surrounding cooling of the magnet through circumferential circulation. This further increases the cooling airflow of the magnet, improves the cooling effect of the magnet, and enhances the cooling and heat dissipation performance of the rotor.

[0073] In some implementations...

[0074] The inner peripheral wall of the magnet groove 7 has at least one location that is spaced from the outer periphery of the magnet 5, and an axial flow groove 5-1 is formed at the space. The axial flow groove 5-1 penetrates the rotor core 2 along the axial direction of the rotor core 2, and the axial flow groove 5-1 is connected to the circumferential flow groove 2-1.

[0075] The present invention further utilizes the axial flow groove structure on the magnet slot to introduce gas into the magnet slot along the axial direction of the rotor core and to reach the circumferential flow groove, thereby achieving enveloping cooling of the magnet, providing cooling airflow for the circumferential flow groove, and further improving the flowability of the cooling gas, thus improving the cooling and heat dissipation performance of the magnet and the rotor.

[0076] In some implementations...

[0077] There are at least two axial flow grooves 5-1, with at least one axial flow groove 5-1 located on one side of the magnet 5 and at least one axial flow groove 5-1 located on the other side of the magnet 5, with one side of the magnet 5 facing the other side. The circumferential flow groove 2-1 is located inside the rotor core 2, that is, the circumferential flow groove 2-1 is spaced from one axial end face of the rotor core 2 by a distance greater than 0, and the circumferential flow groove 2-1 is also spaced from the other axial end face of the rotor core 2 by a distance greater than 0.

[0078] The present invention, through the arrangement of at least two axial flow grooves, at least one of which is located on one side of the magnet and at least one on the other side of the magnet, increases the gas supply to the inside of the magnet groove and the gas supply to the circumferential flow groove, thereby enhancing the cooling and heat dissipation effect on the magnet. Preferably, the circumferential flow groove of the present invention is located at a distance greater than 0 from both axial end faces of the rotor core, so that the circumferential flow groove is located inside the rotor core in the axial direction, thereby effectively realizing the cooling and heat dissipation of the inside of the rotor core, especially the magnet part.

[0079] In some implementations...

[0080] There are multiple magnetic steel grooves 7, which are spaced apart in the circumferential direction of the rotor core 2, and each magnetic steel groove 7 has at least one circumferential flow groove 2-1 and at least one axial flow groove 5-1.

[0081] The present invention, through the above-mentioned preferred plurality of magnet slots, each of which is provided with at least one circumferential flow slot and at least one axial flow slot, enables the magnets in each magnet slot to achieve a surround cooling effect, thereby further improving the cooling and heat dissipation performance of the rotor as a whole.

[0082] In some implementations...

[0083] The rotor core 2 is also provided with an air duct outlet 6-1. One end of the air duct outlet 6-1 is connected to the axial flow groove 5-1, and the other end extends through to the outer periphery of the rotor core 2.

[0084] The present invention utilizes the aforementioned air duct outlet on the rotor core, which connects the axial flow groove to the outer periphery of the rotor core. This allows the gas that has passed through the cooled magnets and rotor core to be discharged to the outer periphery of the rotor core, enabling subsequent cooling gas to continue entering the magnet groove. This achieves gas flow performance and further improves the cooling and heat dissipation performance of the rotor and magnets.

[0085] In some implementations...

[0086] It also includes a rotor baffle 3, which is disposed at one axial end of the rotor core 2, and the rotor baffle 3 has a hollow cavity 8 inside. An air intake channel 3-1 is provided on the outer peripheral wall of the rotor baffle 3 extending toward the interior of the rotor baffle 3. One end of the air intake channel 3-1 is located on the outer wall of the rotor baffle 3, and the other end of the air intake channel 3-1 extends toward the interior of the rotor baffle 3 to communicate with the hollow cavity 8. The air intake channel 3-1 can introduce gas from the outside and guide it into the hollow cavity 8. The hollow cavity 8 can communicate with the magnetic steel groove 7 to introduce gas into the magnetic steel groove 7.

[0087] The present invention also utilizes the aforementioned rotor baffle structure to obstruct the axial direction of the rotor core magnets, preventing them from detaching. Simultaneously, an inward-facing air intake channel is provided on the outer periphery of the rotor baffle, and a hollow cavity is ultimately provided inside the baffle. This allows gas from the outer periphery of the rotor baffle to be introduced into the hollow cavity through the air intake channel, achieving buffering and storage of the gas within the hollow cavity. This further facilitates the supply of gas to the magnet slots, thereby cooling both the rotor baffle and the internal structures of the rotor core, such as the magnets.

[0088] In some implementations...

[0089] The rotor baffle 3 includes a first shaft segment 9 and a second shaft segment 10. The first shaft segment 9 and the second shaft segment 10 are connected together along the axial direction of the rotor baffle 3. The first shaft segment 9 and the second shaft segment 10 are both annular structures and have the same outer diameter. The inner diameter of the first shaft segment 9 is larger than the inner diameter of the second shaft segment 10, so as to form the hollow cavity 8 on the inner circumference of the first shaft segment 9.

[0090] This is the preferred structural form of the rotor baffle forming a hollow cavity in the present invention. By using two shaft sections with different inner diameters, a hollow cavity can be formed on the inner circumference of the section with the larger inner diameter. This allows for gas diffusion and deceleration from the air intake channel to the hollow cavity, making the gas more stable as it enters the hollow cavity and enhancing the supply effect of airflow to the magnet slot.

[0091] In some implementations...

[0092] The second shaft segment 10 includes a first axial end face 11, which is connected to the hollow cavity 8 along the axial direction of the rotor baffle 3. The air intake channel 3-1 is opposite to the first axial end face 11 along the radial direction of the rotor baffle 3, such that the air intake channel 3-1 passes through the outer peripheral wall of the rotor baffle 3 into the interior of the rotor baffle 3, and a portion of the air intake channel 3-1 is located on the first axial end face 11 and faces and communicates with the hollow cavity 8.

[0093] This is a preferred configuration of the air intake channel and the second shaft section of the present invention. By setting the air intake channel to a position opposite to the first axial end face of the second shaft section, the air intake channel enters the hollow cavity while a portion of its structure is located on the first axial end face, thereby effectively extending the length and area of ​​the air intake channel, increasing the air intake volume, and further improving the cooling and heat dissipation effect on the rotor baffle, rotor core, magnets, etc.

[0094] In some implementations...

[0095] Within the projection plane of the axial end face of the rotor baffle 3, the direction from the inlet end to the outlet end of the air intake channel 3-1 is opposite to the rotation direction of the rotor baffle 3; the flow area at the outlet end of the air intake channel 3-1 is larger than the flow area at its inlet end; there are multiple air intake channels 3-1, and the multiple air intake channels 3-1 are spaced apart in the circumferential direction of the rotor baffle 3.

[0096] This invention, through the arrangement of the air intake channel with the direction from the inlet end to the outlet end opposite to the rotation direction of the rotor baffle, can automatically draw airflow into the hollow cavity through the air intake channel as the rotor baffle rotates, achieving automatic gas introduction and automatic cooling of the rotor baffle, rotor core, and magnets. The outlet end area of ​​the air intake channel is larger than the inlet end area, which enables gas pressurization and deceleration, increasing the gas supply and reducing the resistance to entering the hollow cavity. The circumferential spacing of multiple air intake channels further increases the air intake volume, improves the air supply to the rotor core and magnet slots, and enhances the cooling effect on the rotor core and magnets.

[0097] This invention proposes a novel rotor self-cooling structure. A baffle plate has intake holes with a certain curvature, allowing air to be drawn into the internal cavity of the baffle plate as the rotor rotates. A circumferential groove (circumferential flow groove 2-1) is formed at the contact point between the baffle plate and the permanent magnet, communicating with the internal cavity of the baffle plate. The airflow directly enters the permanent magnet slots, achieving axial cooling of the permanent magnets. Simultaneously, some rotor lamination magnet slots are appropriately enlarged, naturally forming annular flow paths for the permanent magnets after lamination, achieving circumferential cooling of the permanent magnets. Therefore, this invention eliminates the need for magnet machining, reducing the internal temperature of the rotor during high-speed operation without affecting motor performance, effectively solving the problem of internal rotor temperature rise, and further improving the rotor's anti-demagnetization capability.

[0098] In some implementations...

[0099] It also includes a first air guide channel 3-3 and a second air guide channel 3-2. The first air guide channel 3-3 is opened on the second axial end face 12 of the rotor baffle 3 facing the rotor core 2, and one end of the first air guide channel 3-3 is connected to the hollow cavity 8. The second air guide channel 3-2 is also opened on the second axial end face 12 and is axially connected to the magnet groove 7. The other end of the first air guide channel 3-3 is connected to the second air guide channel 3-2.

[0100] The present invention utilizes the first and second air guide channels opened on the rotor baffle. The first air guide channel can communicate with the hollow cavity to introduce gas, and the second air guide channel is connected to the first air guide channel to introduce the gas in the first air guide channel. Furthermore, the second air guide channel is opposite to and connected to the magnet slot. This allows the gas in the hollow cavity to be introduced into the magnet slot through the two air guide channels, thereby achieving the function of supplying gas to the magnet slot and improving the cooling effect.

[0101] In some implementations...

[0102] The first air guide channel 3-3 is a groove formed by recessing on the second axial end face 12 in a direction away from the rotor core 2. Along the radial direction of the rotor baffle 3, the radial inner end of the first air guide channel 3-3 communicates with the hollow cavity 8, and the radial outer end of the first air guide channel 3-3 communicates with the second air guide channel 3-2. The second air guide channel 3-2 is a groove formed by recessing on the second axial end face 12 in a direction away from the rotor core 2. The second air guide channel 3-2 is an annular groove. There are multiple first air guide channels 3-3. Multiple first air guide channels 3-3 are spaced apart in the circumferential direction of the rotor baffle 3 and are all connected to the second air guide channel 3-2.

[0103] This is a preferred structural form of the first and second air guide channels of the present invention. The first air guide channel extends radially and there are multiple channels, which can increase the airflow conduction area. The second air guide channel is an annular groove, which can form an annular channel, further increasing the air supply area to the magnet slot and increasing the air supply volume, thereby improving the cooling and heat dissipation effect on the rotor core and magnet.

[0104] In some implementations...

[0105] The rotor baffle 3 is also provided with an air outlet channel 3-4. One end of the air outlet channel 3-4 is connected to the second air guide channel 3-2, and the other end extends to the outer peripheral wall of the rotor baffle 3 so as to discharge gas to the outside of the rotor baffle 3.

[0106] The present invention enables the air outlet channel on the rotor baffle to connect with the second air guide channel, allowing gas that has not entered the magnet slot in the second air guide channel to be discharged to the outside of the rotor baffle through the air outlet channel, thereby improving the gas flow and further enhancing the cooling and heat dissipation performance of the rotor core and magnet.

[0107] The rotor of this invention achieves internal cooling, such as... Figure 6 The rotor rotates counterclockwise, causing the surrounding air to flow. The air is gathered at the air inlet 3-1-1 and drawn into the internal cavity of the rotor baffle through the intake channel 3-1. It is then diverted through the first air guide channel 3-3 to the second air guide channel 3-2. A small amount of air flows out through the outlet channel 3-4, while the rest flows in through the axial flow groove 5-1. The circumferential flow groove 2-1 and the axial flow groove 5-1 achieve comprehensive cooling of the magnets in both the circumferential and axial directions, thereby improving the rotor's anti-demagnetization capability. Alternatively, several laminations can be placed in the middle of the rotor core during lamination. Figure 10 The lamination structure can be adjusted according to the heat dissipation flow requirements. It connects to the outer ring through the axial flow groove 5-1 and opens the air duct outlet 6-1 so that the cooling air can be dissipated in time when it flows through the middle.

[0108] In some implementations...

[0109] An angle θ is formed between the centerline of the inlet end face and the centerline of the outlet end face of the air intake channel 3-1, where θ satisfies the range of 10°≤θ≤30°. The diameter of the inlet end of the air intake channel 3-1 is d1, and the diameter of the outlet end is d2, with 1.2≤d2 / d1≤1.5.

[0110] Within the projection plane of the axial end face of the rotor baffle 3, along the circumferential direction of the rotor baffle 3, the circumferential width of the first air guide channel 3-3 is b, the circumferential width of the air outlet channel 3-4 is c, and 5≤b / c≤12.

[0111] like Figure 6-7 As shown, this invention designs an air inlet channel 3-1 (preferably an arc-shaped air intake), with an angle θ between the arc-shaped inlet and outlet. To reduce eddies and ensure efficient exhaust of the introduced gas, this angle should be 10°≤θ≤30°. Simultaneously, this invention employs a design with different inner and outer diameters, i.e., the outlet diameter d2 is larger than the inlet diameter d1, and their ratio should satisfy 1.2≤d2 / d1≤1.5. This can diffuse pressure and reduce velocity, decrease flow resistance and energy loss, accelerate air inflow, and enhance the cooling effect. Furthermore, the width b of the first air guide channel 3-3 and the width c of the outlet channel 3-4 inside the baffle satisfy 5≤b / c≤12, constraining the flow distribution size to be much larger than the outlet channel size. This prevents air from being diverted to the annular groove and then directly exiting from the outlet channel. After setting the ratio, a pressure difference is formed at the outlet, and most of the air flows into the axial flow groove 5-1, achieving cooling of the magnet's interior.

[0112] The present invention also provides an electric motor, which includes the aforementioned motor rotor assembly.

[0113] This invention proposes a novel built-in rotor self-cooling structure. By using a perforated baffle, air is drawn into the baffle when the rotor rotates. The air is then drawn into the magnet slot through a corresponding groove design. Finally, the internal magnets are cooled through the airflow path naturally formed by the magnet holes and laminations. This cooling method is more efficient and thorough, reducing the internal temperature of the rotor during high-speed operation without affecting the motor performance.

[0114] This invention can solve the problems of high-speed motor rotors causing severe heat generation due to wind wear and eddy current losses during high-speed rotation, and the difficulty in dissipating the temperature of the internal magnets, which easily leads to irreversible high-temperature demagnetization. It also addresses the issue of rotor high temperature causing inconsistency in built-in rotors.

[0115] This invention proposes a novel built-in rotor internal cooling structure, as shown in the following scheme. Figure 1 , Figure 2 As shown, this technical solution mainly includes five parts in this structure: a rotating shaft 1, which is a conventional cylindrical structure; a rotor core 2, which is formed by stacking rotor laminations 6, with its own circumferential flow channel inside; a rotor baffle 3, which has an internal flow channel, and the inlet and outlet rely on the rotation of the rotor to drive the surrounding air, which enters the internal cavity of the rotor baffle through the air inlet guide 3-1-1, and enters the magnet slot through internal diversion, realizing all-round cooling of the magnet in both circumferential and axial directions; another rotor baffle 3, the two rotor baffles are assembled face to face, and it is necessary to ensure that the air inlet channel 3-1 (arc-shaped air intake) is in the correct air intake direction as the rotor rotates; and an embedded magnet 5, which has a cuboid structure. Figure 3 The exploded view of the rotor assembly shows only one pole of magnet 5, and only the corresponding slot of one pole magnet is shown in the rotor core 2; the other poles have the same corresponding features.

[0116] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention. The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present invention, and these improvements and modifications should also be considered within the protection scope of the present invention.

Claims

1. A motor rotor assembly, characterized in that: include: The rotor core (2) and magnet (5) are provided. The rotor core (2) is provided with a magnet slot (7). The magnet (5) can be placed in the magnet slot (7). Along the axial direction of the rotor core (2), there is at least one slot segment on the magnet slot (7), which is a circumferential flow slot (2-1). The flow area of ​​the circumferential flow slot (2-1) is larger than the flow area of ​​a part of the magnet slot (7) connected to it along the axial direction. That is, in the projection plane of the axial end face of the rotor core (2), the area of ​​the circumferential flow slot (2-1) is larger than the flow area of ​​a part of the magnet slot (7) connected to it along the axial direction. There is a gap between the inner wall of the circumferential flow slot (2-1) and the outer periphery of the magnet (5), so that gas can enter the circumferential flow slot (2-1) to surround and cool the magnet (5). The rotor core (2) includes multiple rotor laminations (6), which are stacked together along the axial direction of the rotor core (2). Each rotor lamination (6) is provided with a magnetic slot unit. The magnetic slot units on the multiple rotor laminations (6) are opposite to each other along the axial direction and connected to form the magnetic slot (7). The multiple rotor laminations (6) include at least one heat dissipation lamination (4). The magnetic slot unit on the heat dissipation lamination (4) is the circumferential flow groove (2-1). In the projection plane of the axial end face of the rotor core (2), the area of ​​the circumferential flow groove (2-1) of the heat dissipation lamination (4) is larger than the area of ​​the magnetic slot unit on the rotor lamination (6) that is axially adjacent to it. It also includes a rotor baffle (3), which is disposed at one axial end of the rotor core (2), and the rotor baffle (3) has a hollow cavity (8) inside. An air intake channel (3-1) is provided on the outer peripheral wall of the rotor baffle (3) extending toward the interior of the rotor baffle (3).

2. The motor rotor assembly according to claim 1, characterized in that: The circumferential flow groove (2-1) on the heat dissipation fin extends beyond the magnetic steel groove unit on the axially adjacent rotor fin (6) by a dimension in any direction, which is the groove depth of the circumferential flow groove (2-1), and the value of a ranges from 0.1 to 0.5 mm; the heat dissipation fin consists of 1 to 2 fins stacked together, and the rotor fins (6) on one axial side of the stacked heat dissipation fins consist of 4 to 8 fins, and the rotor fins (6) on the other axial side also consist of 4 to 8 fins.

3. The motor rotor assembly according to claim 1, characterized in that: Within the projection plane of the axial end face of the rotor core (2), the circumferential flow groove (2-1) is a polygonal structure or a curved structure, and there is a gap between each side of the polygon or any point on the curved structure and the outer periphery of the magnet (5) to form a surrounding cooling of the circumferential circulation of the magnet (5).

4. The motor rotor assembly according to claim 1, characterized in that: The inner circumferential wall of the magnet groove (7) has at least one position that is spaced from the outer circumference of the magnet (5), and an axial flow groove (5-1) is formed at the space. The axial flow groove (5-1) passes through the rotor core (2) along the axial direction, and the axial flow groove (5-1) is connected to the circumferential flow groove (2-1).

5. The motor rotor assembly according to claim 4, characterized in that: There are at least two axial flow grooves (5-1), at least one of which is located on one side of the magnet (5) and at least one of which is located on the other side of the magnet (5). One side of the magnet (5) is opposite to the other side. The circumferential flow groove (2-1) is located inside the rotor core (2), that is, the circumferential flow groove (2-1) is spaced from one end face of the rotor core (2) by a distance greater than 0, and the circumferential flow groove (2-1) is also spaced from the other end face of the rotor core (2) by a distance greater than 0.

6. The motor rotor assembly according to claim 4, characterized in that: There are multiple magnetic steel grooves (7), which are spaced apart in the circumferential direction of the rotor core (2), and each magnetic steel groove (7) has at least one circumferential flow groove (2-1) and at least one axial flow groove (5-1).

7. The motor rotor assembly according to claim 4, characterized in that: The rotor core (2) is also provided with an air duct outlet (6-1), one end of which is connected to the axial flow groove (5-1), and the other end extends to the outer periphery of the rotor core (2).

8. The motor rotor assembly according to claim 1, characterized in that: One end of the air intake channel (3-1) is located on the outer wall of the rotor baffle (3), and the other end of the air intake channel (3-1) extends toward the interior of the rotor baffle (3) to communicate with the hollow cavity (8). The air intake channel (3-1) can introduce gas from the outside and guide it into the hollow cavity (8). The hollow cavity (8) can communicate with the magnetic steel groove (7) to introduce gas into the magnetic steel groove (7).

9. The motor rotor assembly according to claim 8, characterized in that: The rotor baffle (3) includes a first shaft segment (9) and a second shaft segment (10). The first shaft segment (9) and the second shaft segment (10) are connected together along the axial direction of the rotor baffle (3). The first shaft segment (9) and the second shaft segment (10) are both annular structures and have the same outer diameter. The inner diameter of the first shaft segment (9) is larger than the inner diameter of the second shaft segment (10) to form the hollow cavity (8) on the inner circumference of the first shaft segment (9).

10. The motor rotor assembly according to claim 9, characterized in that: The second shaft segment (10) includes a first axial end face (11), which is connected to the hollow cavity (8) along the axial direction of the rotor baffle (3). The air intake channel (3-1) is opposite to the first axial end face (11) along the radial direction of the rotor baffle (3), such that the air intake channel (3-1) passes through the outer peripheral wall of the rotor baffle (3) into the interior of the rotor baffle (3), such that a portion of the air intake channel (3-1) is located on the first axial end face (11) and faces and communicates with the hollow cavity (8).

11. The motor rotor assembly according to claim 8, characterized in that: Within the projection plane of the axial end face of the rotor baffle (3), the direction from the inlet end to the outlet end of the air intake channel (3-1) is opposite to the rotation direction of the rotor baffle (3); the flow area at the outlet end of the air intake channel (3-1) is larger than the flow area at its inlet end; there are multiple air intake channels (3-1), and the multiple air intake channels (3-1) are spaced apart in the circumferential direction of the rotor baffle (3).

12. The motor rotor assembly according to claim 8, characterized in that: It also includes a first air guide channel (3-3) and a second air guide channel (3-2). The first air guide channel (3-3) is opened on the second axial end face (12) of the rotor baffle (3) facing the rotor core (2), and one end of the first air guide channel (3-3) is connected to the hollow cavity (8). The second air guide channel (3-2) is also opened on the second axial end face (12) and is axially connected to the magnet slot (7). The other end of the first air guide channel (3-3) is connected to the second air guide channel (3-2).

13. The motor rotor assembly according to claim 12, characterized in that: The first air guide channel (3-3) is a groove formed by recessing on the second axial end face (12) in a direction away from the rotor core (2). Along the radial direction of the rotor baffle (3), the inner radial end of the first air guide channel (3-3) is connected to the hollow cavity (8), and the outer radial end of the first air guide channel (3-3) is connected to the second air guide channel (3-2). The second air guide channel (3-2) is a groove formed by recessing on the second axial end face (12) in a direction away from the rotor core (2). The second air guide channel (3-2) is an annular groove. There are multiple first air guide channels (3-3). Multiple first air guide channels (3-3) are spaced apart in the circumferential direction of the rotor baffle (3) and are all connected to the second air guide channel (3-2).

14. The motor rotor assembly according to claim 12, characterized in that: The rotor baffle (3) is also provided with an air outlet channel (3-4). One end of the air outlet channel (3-4) is connected to the second air guide channel (3-2), and the other end extends to the outer peripheral wall of the rotor baffle (3) so as to exhaust the gas to the outside of the rotor baffle (3).

15. The motor rotor assembly according to claim 14, characterized in that: The centerline of the inlet end face of the air intake channel (3-1) and the centerline of the outlet end face are provided at an angle θ, where θ satisfies the range of 10°≤θ≤30°. The diameter of the inlet end of the air intake channel (3-1) is d1, and the diameter of the outlet end is d2, with 1.2≤d2 / d1≤1.

5. Within the projection plane of the axial end face of the rotor baffle (3), along the circumferential direction of the rotor baffle (3), the circumferential width of the first air guide channel (3-3) is b, the circumferential width of the air outlet channel (3-4) is c, and 5≤b / c≤12.

16. An electric motor, characterized in that: Includes the motor rotor assembly according to any one of claims 1-15.

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