Electric motor rotor, drive motor and vehicle

Abstract

The application discloses a motor rotor, a driving motor and a vehicle, and belongs to the driving motor field.The motor rotor comprises a rotor shaft and a rotor magnetic circuit component.The rotor shaft comprises a shaft base body and a connecting sleeve.The connecting sleeve is coaxially arranged with the shaft base body and is fixedly connected with the shaft base body, and the connecting sleeve is used for being connected with a transmission part.The rotor magnetic circuit component is sleeved outside the shaft base body.The density of the shaft base body is smaller than the density of the connecting sleeve.The strength of the connecting sleeve is greater than the strength of the shaft base body, and the hardness of the connecting sleeve is greater than the hardness of the shaft base body.The strength and the hardness of the connecting sleeve are relatively large, so that the connecting sleeve can output a certain torque.A material with relatively small strength and hardness is used to manufacture the shaft base body, so that the cost of the rotor shaft is reduced.Further, the density of the shaft base body is smaller than the density of the connecting sleeve, so that the weight of the shaft base body can be reduced under the same volume.

Description

Technical Field

[0001] This application relates to the field of drive motors, and in particular to a motor rotor, a drive motor, and a vehicle. Background Technology

[0002] As a power source for various power equipment, the drive motor can convert electrical energy into mechanical energy. The motor mainly consists of a stator and a rotor. The stator is fixed on the motor housing, and the rotor is rotatably fitted inside the stator.

[0003] Currently, drive motors are developing towards higher performance, lighter weight, and lower cost.

[0004] However, the large weight and high cost of the motor rotor of the drive motor have hindered the development of drive motors towards lightweight and low-cost designs. Summary of the Invention

[0005] This application provides an electric motor rotor, a drive motor, and a vehicle. It solves the problems of large weight and high cost of electric motor rotors in related technologies. The technical solution is as follows: In a first aspect, an electric motor rotor is provided, comprising: a rotor shaft and a rotor magnetic circuit assembly; The rotor shaft includes: a shaft base and a connecting sleeve; the connecting sleeve is coaxially arranged and fixedly connected to the shaft base, and the connecting sleeve is used to connect with a transmission component. The rotor magnetic circuit assembly is sleeved on the outside of the shaft base; Wherein, the density of the shaft base is less than the density of the connecting sleeve; the strength of the connecting sleeve is greater than the strength of the shaft base, and the hardness of the connecting sleeve is greater than the hardness of the shaft base.

[0006] In some possible implementations, the shaft base is provided with a hollow channel extending axially through the shaft base; the connecting sleeve is fixedly embedded in the hollow channel; The inner wall of the connecting sleeve is provided with an internal spline, and the connecting sleeve is connected to the transmission component through the internal spline.

[0007] In some possible implementations, the inner wall of the hollow channel is provided with an embedding groove; at least a portion of the connecting sleeve is fixed in the embedding groove and is tightly connected to the groove surface of the embedding groove.

[0008] In some possible implementations, the wall thickness of the connecting sleeve is greater than or equal to the groove depth of the embedding groove.

[0009] In some possible implementations, the outer wall of the connecting sleeve is provided with a plurality of protrusions; the plurality of protrusions are spaced apart in the outer peripheral direction of the connecting sleeve; The embedding groove is provided with a plurality of auxiliary reinforcing grooves, and the plurality of auxiliary reinforcing grooves correspond one-to-one with the plurality of protrusions. Each protrusion is embedded and fixed in the corresponding auxiliary reinforcing groove and is tightly connected to the groove surface of the corresponding auxiliary reinforcing groove.

[0010] In some possible implementations, the shaft base includes: a first shaft segment, a second shaft segment, and a third shaft segment connected sequentially in the axial direction; the outer diameters of the first shaft segment and the third shaft segment are both smaller than the outer diameter of the second shaft segment; the rotor magnetic circuit assembly is sleeved on the outside of the second shaft segment; Wherein, a portion of the embedding groove is located on the inner wall of the second shaft segment, and another portion is located on the inner wall of the first shaft segment; and the axial length of the embedding groove located on the inner wall of the second shaft segment is greater than or equal to the axial length of the embedding groove located on the inner wall of the first shaft segment; the embedding groove located on the inner wall of the second shaft segment is provided with a plurality of the auxiliary reinforcing grooves.

[0011] In some possible implementations, the connecting sleeve is fixedly fitted onto the outside of the shaft base, and the outer wall of the connecting sleeve is provided with an external spline, and the connecting sleeve is connected to the transmission component through the external spline.

[0012] In some possible implementations, the shaft base is a shaft structure made of cast iron, and / or the connecting sleeve is a sleeve structure made of steel.

[0013] In a second aspect, a drive motor is provided, comprising: a motor stator and a motor rotor as described above.

[0014] Thirdly, a vehicle is provided, including the drive motor described above.

[0015] The beneficial effects of the technical solutions provided in this application include at least the following: This application divides the rotor shaft of the motor rotor into two parts: the shaft base and the connecting sleeve. Since the connecting sleeve connects to the transmission components, its strength and hardness are set relatively high to ensure effective torque output. The shaft base, on the other hand, is made of a material with relatively lower strength and hardness to reduce the cost of the rotor shaft and consequently, the cost of the motor rotor including the shaft. Furthermore, the density of the shaft base is lower than that of the connecting sleeve, thus reducing the weight of the shaft base within the same volume, and consequently, the weight of the motor rotor including the shaft. In addition, the independent design of the shaft base and connecting sleeve allows for flexible material selection based on usage and design requirements, giving the rotor shaft greater design flexibility. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a schematic cross-sectional view of a motor rotor provided in an embodiment of this application; Figure 2 This is a schematic cross-sectional view of another motor rotor provided in an embodiment of this application; Figure 3 This is a schematic cross-sectional view of a rotor shaft provided in an embodiment of this application; Figure 4 This is a cross-sectional structural diagram of a shaft base provided in an embodiment of this application; Figure 5 This is a schematic diagram of the structure of a connecting sleeve provided in an embodiment of this application; Figure 6 This is a schematic diagram of another connecting sleeve provided in an embodiment of this application; Figure 7 This is a schematic diagram of another connecting sleeve provided in an embodiment of this application; Figure 8 This is a schematic diagram of the structure of a shaft blank provided in an embodiment of this application; Figure 9 This is a schematic diagram of the structure of a motor rotor provided in an embodiment of this application; Figure 10 This is a schematic diagram of the structure of a rotor shaft provided in an embodiment of this application. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of this application clearer, the embodiments of this application will be described in further detail below with reference to the accompanying drawings.

[0019] With the development of technology, new energy vehicles have become a new development trend. The popularization of new energy vehicles is of great significance for addressing climate change, breaking free from the "oil shackles," ensuring energy security, optimizing the energy structure, and promoting renewable energy.

[0020] With the popularization of new energy vehicles, the industry is developing rapidly, and market competition is becoming increasingly fierce. Furthermore, the market has high requirements for the cost and range of new energy vehicles. Therefore, in order to cope with market competition, the drive motors of new energy vehicles are developing towards higher performance, lighter weight, and lower cost.

[0021] Currently, the performance of drive motors in new energy vehicles is becoming increasingly sophisticated, and their power and torque output relies on the rotor shaft. To ensure the effective output power and torque of the rotor shaft, it is typically made of materials with high strength and high hardness.

[0022] While this ensures sufficient strength and rigidity for the rotor shaft, it also results in a larger rotor shaft weight and higher cost, which is detrimental to the development of lightweight and low-cost drive motors that include this rotor shaft.

[0023] Based on this, this application provides a motor rotor that can reduce the weight and cost of the rotor shaft while ensuring the hardness and strength of the rotor shaft, so as to facilitate the development of the drive motor corresponding to the motor rotor towards lightweight and low cost.

[0024] Figure 1 This is a cross-sectional structural diagram of a motor rotor provided in an embodiment of this application. Please refer to it. Figure 1 This application provides a motor rotor 000, including a rotor shaft 010 and a rotor magnetic circuit assembly 020.

[0025] The rotor shaft 010 includes a shaft base 011 and a connecting sleeve 012. The connecting sleeve 012 is coaxially arranged and fixedly connected to the shaft base 011, and is used to connect to a transmission component. The transmission component is, for example, the power input shaft of a reducer.

[0026] The rotor magnetic circuit assembly 020 is sleeved on the outside of the shaft base 011.

[0027] The density of the shaft base 011 is less than that of the connecting sleeve 012. The strength of the connecting sleeve 012 is greater than that of the shaft base 011, and the hardness of the connecting sleeve 012 is greater than that of the shaft base 011.

[0028] In summary, this application divides the rotor shaft of the motor rotor into two parts: the shaft base and the connecting sleeve. Since the connecting sleeve connects to the transmission components, to ensure the output torque of the connecting sleeve, its strength and hardness are set to be relatively high, so that the connecting sleeve can output a certain torque. The shaft base, on the other hand, is made of a material with relatively lower strength and hardness to reduce the cost of the rotor shaft, thereby reducing the cost of the motor rotor including the rotor shaft. Furthermore, the density of the shaft base is lower than that of the connecting sleeve, thus reducing the weight of the shaft base within the same volume, and consequently reducing the weight of the motor rotor including the rotor shaft. In addition, the independent design of the shaft base and connecting sleeve allows for flexible material selection based on usage and design requirements, giving the rotor shaft greater design flexibility.

[0029] It is understandable that when the weight and cost of the motor rotor 000 are reduced, the weight and cost of the drive motor, including the motor rotor 000, can be reduced, thus facilitating the development of the drive motor towards higher performance, lighter weight, and lower cost. The term "relative" refers to the relative comparison between the connecting sleeve 012 and the shaft base 011 in the rotor shaft 010. For example, the connecting sleeve 012 may have greater strength and hardness than the shaft base 011, or the density of the shaft base 011 may be lower than that of the connecting sleeve 012.

[0030] Figure 2 This is a cross-sectional structural diagram of another motor rotor provided in an embodiment of this application. Please refer to it. Figure 2 In some possible implementations, the shaft base 011 has a hollow channel T that extends axially through the shaft base 011, that is, the shaft base 011 is set as a hollow shaft. The connecting sleeve 012 is fixedly embedded in the hollow channel T, that is, the shaft base 011 is sleeved and fixed on the outside of the connecting sleeve 012 through the hollow channel T.

[0031] The inner wall of the connecting sleeve 012 is provided with an internal spline. The connecting sleeve 012 is connected to the external spline on the transmission component through the internal spline, thereby outputting a certain torque.

[0032] By providing a hollow channel T that extends axially through the shaft base 011, machining the shaft base 011 is facilitated, thereby improving machining efficiency and reducing machining costs. The connecting sleeve 012 is fixedly embedded within the hollow channel T of the shaft base 011, allowing for a smaller overall structure design. A smaller connecting sleeve 012 reduces its weight, consequently reducing the weight of the motor rotor 000 and the drive motor including it, and also lowers the cost of the connecting sleeve 012, and consequently the cost of the motor rotor 000 and the drive motor including it.

[0033] Figure 3 This is a cross-sectional structural diagram of a rotor shaft provided in an embodiment of this application. Figure 4 This is a cross-sectional structural diagram of a shaft base provided in an embodiment of this application. Please refer to it. Figures 3-4 In some possible implementations, the inner wall of the hollow channel T is provided with an embedding groove C1. At least a portion of the connecting sleeve 012 is fixed in the embedding groove C1 and is tightly connected to the groove surface of the embedding groove C1.

[0034] By fixing at least a portion of the connecting sleeve 012 within the embedded groove C1, the contact area between the connecting sleeve 012 and the shaft base 011 can be increased, thereby increasing the connection strength between the connecting sleeve 012 and the shaft base 011 and the torque transmission capability. Furthermore, the space within the shaft base 011 can be fully utilized, improving the space utilization rate within the shaft base 011 while also making the overall structure of the rotor shaft 010 more compact.

[0035] Please refer to Figure 3 In some possible implementations, the wall thickness of the connecting sleeve 012 is greater than or equal to the groove depth of the embedded groove C1.

[0036] It is understood that the wall thickness of the connecting sleeve 012 and the groove depth of the embedded groove C1 mentioned here are both radial dimensions of the rotor shaft 010.

[0037] By setting the wall thickness of the connecting sleeve 012 to be greater than or equal to the groove depth of the embedded groove C1, it is easy to connect the connecting sleeve 012 to the transmission component via the internal spline.

[0038] For example, the wall thickness of the connecting sleeve 012 can be greater than the groove depth of the embedding groove C1, that is, a portion of the connecting sleeve 012 can protrude radially and be distributed on the outside of the embedding groove C1. When the wall thickness of the connecting sleeve 012 is greater than the groove depth of the embedding groove C1, the connecting sleeve 012 can have better structural strength, thereby enabling the connecting sleeve 012 to withstand and output greater torque.

[0039] Figure 5 This is a schematic diagram of a connecting sleeve provided in an embodiment of this application. Please refer to it. Figures 4-5 In some possible implementations, the outer wall of the connecting sleeve 012 is provided with a plurality of protrusions B. The plurality of protrusions B are distributed at intervals in the outer peripheral direction of the connecting sleeve 012.

[0040] The groove C1 is provided with multiple auxiliary reinforcing grooves C2. Each auxiliary reinforcing groove C2 corresponds to a multiple protrusion B. Each protrusion B is embedded and fixed in the corresponding auxiliary reinforcing groove C2 and is tightly connected to the groove surface of the corresponding auxiliary reinforcing groove C2.

[0041] By providing multiple protrusions B spaced apart in the outer circumferential direction on the outer wall of the connecting sleeve 012, and providing multiple auxiliary reinforcing grooves C2 corresponding one-to-one with the multiple protrusions B in the groove of the embedding groove C1, each protrusion B is embedded and fixed in the corresponding auxiliary reinforcing groove C2, and the protrusion B is tightly connected to the groove surface of the corresponding auxiliary reinforcing groove C2, the contact area between the connecting sleeve 012 and the shaft base 011 can be further increased, thereby increasing the connection strength between the connecting sleeve 012 and the shaft base 011 and the torque transmission capability.

[0042] For example, the multiple protrusions B may be two, three, four, five, or six protrusions B, and the multiple protrusions B may be evenly distributed on the outer periphery of the connecting sleeve 012.

[0043] The shape of the protrusion B can be rectangular, trapezoidal, triangular, polygonal, semi-circular, or other irregular shapes. As long as the protrusion B can increase the contact area between the connecting sleeve 012 and the shaft base 011, this application does not impose any restrictions on the specific shape design of the protrusion B; it can be flexibly selected according to the actual situation.

[0044] Please refer to Figure 1 and Figure 4 In some possible implementations, the shaft base 011 includes a first shaft segment 0111, a second shaft segment 0112, and a third shaft segment 0113 connected sequentially in the axial direction. The outer diameters of the first shaft segment 0111 and the third shaft segment 0113 are both smaller than the outer diameter of the second shaft segment 0112. The rotor magnetic circuit assembly 020 is sleeved on the outside of the second shaft segment 0112.

[0045] A portion of the embedding groove C1 is located on the inner wall of the second shaft segment 0112, and another portion is located on the inner wall of the first shaft segment 0111. The axial length of the embedding groove C1 located on the inner wall of the second shaft segment 0112 is greater than or equal to the axial length of the embedding groove C1 located on the inner wall of the first shaft segment 0111. The embedding groove C1 located on the inner wall of the second shaft segment 0112 is provided with multiple auxiliary reinforcing grooves C2.

[0046] For example, the hollow channel T within the shaft base 011 can be a circular hollow channel T, meaning the diameters of the hollow channel T in the first shaft segment 0111, the second shaft segment 0112, and the third shaft segment 0113 are all the same. In this case, the outer diameter of the second shaft segment 0112 is larger than that of the first shaft segment 0111 and the third shaft segment 0113, meaning the wall thickness of the second shaft segment 0112 is larger than that of the first shaft segment 0111 and the third shaft segment 0113.

[0047] Since the outer diameters of the first shaft segment 0111 and the third shaft segment 0113 are both smaller than the outer diameter of the second shaft segment 0112, setting the axial length of the embedding groove C1 on the inner wall of the second shaft segment 0112 to be greater than or equal to the axial length of the embedding groove C1 on the inner wall of the first shaft segment 0111 allows the embedding groove C1 to be distributed more extensively in the second shaft segment 0112 in the axial direction. This avoids the impact of opening the embedding groove C1 in the hollow channel T on the strength of the shaft base 011, and thus better protects the strength of the shaft base 011.

[0048] Multiple auxiliary reinforcing grooves C2 are set in the embedded groove C1 on the inner wall of the second shaft segment 0112 with a larger outer diameter. On the one hand, the impact of opening multiple auxiliary reinforcing grooves C2 on the strength of the shaft base 011 can be reduced. On the other hand, the space inside the second shaft segment 0112 is larger, which makes it easier to process the auxiliary reinforcing grooves C2. Furthermore, the space inside the second shaft segment 0112 can be fully utilized to improve the space utilization rate of the shaft base 011.

[0049] Please refer to Figure 5 In one possible implementation, the connecting sleeve 012 has two axial end faces, namely a first end face M1 and a second end face M2. The first end face M1 is located in the hollow channel T of the first shaft segment 0111, and the second end face M2 is located in the hollow channel T of the second shaft segment 0112.

[0050] The connecting sleeve 012 has a plurality of protrusions B on its outer periphery near the second end face M2. The side of each protrusion B facing away from the first end face M1 can be flush with the second end face M2 of the connecting sleeve 012, or each protrusion B is located between the first end face M1 and the second end face M2 of the connecting sleeve 012.

[0051] Correspondingly, multiple auxiliary reinforcing grooves C2 are provided on the embedding groove C1 located on the inner wall of the second shaft segment 0112, each corresponding to a multiple protrusion B.

[0052] Figure 6 This is a schematic diagram of another connecting sleeve provided in an embodiment of this application. Please refer to it. Figure 6 In another possible implementation, the connecting sleeve 012 has a first end face M1 and a second end face M2 at its two ends in the axial direction. The first end face M1 is located in the hollow channel T of the first shaft segment 0111, and the second end face M2 is located in the hollow channel T of the second shaft segment 0112.

[0053] The connecting sleeve 012 may have multiple protrusions B on its outer periphery near the first end face M1 and on its outer periphery near the second end face M2. That is, the connecting sleeve 012 has two rings of protrusions on its outer periphery. One ring of protrusions is located at the end of the connecting sleeve 012 near the first end face M1, and the other ring of protrusions is located at the end of the connecting sleeve 012 near the second end face M2.

[0054] Furthermore, among the protrusions B located near the first end face M1, each protrusion B, on the side facing away from the second end face M2, can be flush with the first end face M1 of the connecting sleeve 012, or each protrusion B can be located between the first end face M1 and the second end face M2. Similarly, among the protrusions B located near the second end face M2, each protrusion B, on the side facing away from the first end face M1, can be flush with the second end face M2 of the connecting sleeve 012, or each protrusion B can be located between the first end face M1 and the second end face M2.

[0055] Correspondingly, the embedding groove C1 on the inner wall of the first shaft segment 0111 is provided with a plurality of auxiliary reinforcing grooves C2 that correspond one-to-one with the plurality of protrusions B on the connecting sleeve 012 near the first end face M1, and the embedding groove C1 on the inner wall of the second shaft segment 0112 is provided with a plurality of auxiliary reinforcing grooves C2 that correspond one-to-one with the plurality of protrusions B on the connecting sleeve 012 near the second end face M2.

[0056] In another possible implementation, the connecting sleeve 012 has a first end face M1 and a second end face M2 at its two ends in the axial direction. The first end face M1 is located in the hollow channel T of the first shaft segment 0111, and the second end face M2 is located in the hollow channel T of the second shaft segment 0112.

[0057] Multiple protrusions B may be provided on the outer periphery of the connecting sleeve 012. The axial extension length of the protrusions B may be equal to or less than the axial length of the connecting sleeve 012. For example, please refer to... Figure 7 , Figure 7 This is a schematic diagram of another connecting sleeve provided in an embodiment of this application. The axial extension length of the protrusion B can be equal to the axial length of the connecting sleeve 012. In this case, the two end faces of the protrusion B in the axial direction are flush with the first end face M1 and the second end face M2, respectively. Alternatively, the axial extension length of the protrusion B can be less than the axial length of the connecting sleeve 012. In this case, the protrusion B can be located between the first end face M1 and the second end face M2 in the axial direction, or one end face of the two end faces of the protrusion B in the axial direction is flush with the first end face M1, or the other end face of the two end faces of the protrusion B in the axial direction is flush with the second end face M2.

[0058] Correspondingly, the auxiliary reinforcing groove C2 provided on the embedded groove C1 has the same axial length as the protrusion B, and their positions are corresponding. That is, the auxiliary reinforcing groove C2 can be located entirely within the second shaft segment 0112 in the axial direction, or part of the auxiliary reinforcing groove C2 can be located within the first shaft segment 0111, and the other part can be located within the second shaft segment 0112.

[0059] This application does not impose specific restrictions on the layout and length of the protrusion B on the connecting sleeve 012 in the axial direction of the connecting sleeve 012; the specific arrangement can be flexibly selected according to actual needs.

[0060] In other possible implementations, the connecting sleeve 012 is fixedly sleeved on the outside of the shaft base 011, and the outer wall of the connecting sleeve 012 is provided with an external spline. The connecting sleeve 012 is connected to the transmission component through the external spline.

[0061] By fixing the connecting sleeve 012 to the outside of the shaft base 011, it is convenient to provide an external spline on the outer wall of the connecting sleeve 012, thereby facilitating the connection of the connecting sleeve 012 to the transmission component through the external spline.

[0062] When the connecting sleeve 012 is fixedly sleeved on the outside of the shaft base 011, for example, the connecting sleeve 012 can be fixedly sleeved on the outside of the first shaft segment 0111 in the shaft base 011, or a part of the connecting sleeve 012 can be fixedly sleeved on the outside of the first shaft segment 0111 in the shaft base 011, and another part can be fixedly sleeved on the outside of the second shaft segment 0112 in the shaft base 011.

[0063] Furthermore, to increase the connection strength and torque transmission capability between the connecting sleeve 012 and the shaft base 011, a convex-concave fit structure can be provided between the connecting sleeve 012 and the shaft base 011 to increase the contact area between them. For example, multiple protrusions can be provided on the inner ring of the connecting sleeve 012, and correspondingly, multiple recesses can be provided on the shaft base 011. By having multiple protrusions and recesses in a one-to-one convex-concave fit, the contact area between the connecting sleeve 012 and the shaft base 011 is increased, thereby increasing the connection strength and torque transmission capability between them.

[0064] Please refer to Figure 3 In some possible implementations, the shaft base 011 is a shaft structure made of cast iron, and / or the connecting sleeve 012 is a sleeve structure made of steel.

[0065] Since cast iron has a relatively low density and cost, by setting the shaft base 011 to a shaft structure made of cast iron material, the weight and material cost of the rotor shaft 010 can be effectively reduced. It also facilitates reducing process difficulty, improving processing efficiency, and reducing processing costs.

[0066] Steel has excellent mechanical properties and relatively high strength and hardness. Therefore, by setting the connecting sleeve 012 to a sleeve structure made of steel, the strength and hardness requirements of the connecting sleeve 012 can be met, so that the connecting sleeve 012 can output torque to the transmission component.

[0067] The rotor shaft 010 in this application achieves high strength, high hardness, and wear resistance in the key part (i.e., the connecting sleeve 012) that connects to the transmission component, while also reducing the overall weight and cost of the rotor shaft 010.

[0068] For example, in this application, the shaft base 011 of the rotor shaft 010 is made of cast iron, and the connecting sleeve 012 is made of steel. The machining method of the rotor shaft 010 in this application is described below: Figure 8 This is a schematic diagram of the structure of a shaft blank provided in an embodiment of this application. Please refer to it. Figure 8 When machining the rotor shaft 010, firstly, a steel connecting sleeve blank 030 is prepared in advance. Then, when casting the shaft base blank 040, the steel connecting sleeve blank 030 is placed in the casting mold, and the steel connecting sleeve blank 030 and the cast iron shaft base blank 040 are integrally machined to form the shaft blank 050. Next, Figure 8 The shaft blank 050 shown is machined into Figure 3 The rotor shaft 010 is shown.

[0069] The connecting sleeve blank 030 has a protrusion B on its outer periphery. When the connecting sleeve blank 030 and the shaft base blank 040 are cast as one piece, the protrusion B on the connecting sleeve blank 030 is embedded and fixed in the auxiliary reinforcing groove C2 on the shaft base blank 040.

[0070] For example, after the connecting sleeve 012 is processed, a localized quenching treatment can be performed on the connecting sleeve 012 to improve its surface strength and hardness. This allows the connecting sleeve 012 to withstand heavy loads without breaking and to be wear-resistant during later use, enabling the connecting sleeve 012 to output greater torque and adapt to high-speed motor transmission conditions. For example, the connecting sleeve 012 can be subjected to induction hardening, carbonitriding, or carburizing and quenching heat treatments to further improve the strength and hardness of the spline.

[0071] Currently, the rotor shafts of drive motors in new energy vehicles are mostly hollow shafts. Existing drive motor shafts on the market are generally hollowed out in two ways: First, a solid shaft blank is drilled in the middle and then machined to become hollow. This method is costly, has low material utilization, and high tool wear. Second, a rotary forging process is used. A hole is machined inside the shaft, and then the end of the shaft is necked through rotary forging to create a hollow shaft. This method is costly and incurs additional mold costs.

[0072] Since the shaft base 011 in the rotor shaft 010 is made of cast iron, the shaft base blank 040 can be machined using a casting method. That is, the shaft base blank 040 can be machined using a casting mold, and after exiting the mold, it can be directly made as a hollow shaft base blank 040, eliminating the need for drilling or forging the central shaft. This improves material utilization, reduces machining tool wear, lowers blank costs, reduces machining costs, saves materials, and is energy-efficient and environmentally friendly. Furthermore, the machining of the shaft base blank 040 in this application is easier to achieve and more efficient.

[0073] Figure 9 This is a schematic diagram of the structure of a motor rotor provided in an embodiment of this application. Figure 2 The schematic diagram of the cross-sectional structure of the motor rotor shown can be used as follows: Figure 9 The diagram shows a cross-sectional view of the motor rotor.

[0074] Please refer to Figure 2 and Figure 9 In some possible implementations, the motor rotor 000 may also include: a first balance disc 060 and a second balance disc 070.

[0075] The first balance disc 060, the rotor magnetic circuit assembly 020, and the second balance disc 070 can be sequentially and fixedly sleeved on the outside of the second shaft segment 0112 in the shaft base 011.

[0076] The rotor magnetic circuit assembly 020 may include a rotor core 021 and magnets 022. The rotor core 021 may be formed by stacking thin laminations, and multiple rotor cores 021 may be stacked and fixedly fitted onto the outside of the second shaft segment 0112. The magnets 022 may be fixed inside the rotor core 021.

[0077] Figure 10 This is a schematic diagram of the structure of a rotor shaft provided in an embodiment of this application. Figure 3 The schematic diagram of the cross-sectional structure of the rotor shaft shown can be used as follows: Figure 10 The diagram shows a cross-sectional view of the rotor shaft.

[0078] Please refer to Figures 9-10 For example, the outer periphery of the second shaft segment 0112 in the shaft base 011 may also include a retaining ring 01121. The retaining ring 01121 may be located on the side of the second shaft segment 0112 close to the first shaft segment 0111, and the first balance disk 060 is closer to the first shaft segment 0111 than the second balance disk 070.

[0079] In this way, when assembling the first balance disk 060, the rotor magnetic circuit assembly 020, and the second balance disk 070 on the second shaft segment 0112, the retaining ring 01121 can be used to position and limit the side of the first balance disk 060 away from the second balance disk 070, thereby facilitating the assembly of the first balance disk 060, the rotor magnetic circuit assembly 020, and the second balance disk 070 on the second shaft segment 0112, and ensuring the accuracy of assembling the first balance disk 060, the rotor magnetic circuit assembly 020, and the second balance disk 070.

[0080] To clearly illustrate the structure and assembly relationship of the motor rotor 000 of this application, the following detailed description of each component, connection method and mating structure is provided in conjunction with the accompanying drawings.

[0081] Please refer to Figures 2-3 In one embodiment, the motor rotor 000 includes a rotor shaft 010 and a rotor magnetic circuit assembly 020.

[0082] The rotor shaft 010 includes a shaft base 011 and a connecting sleeve 012. The shaft base 011 has a hollow channel T that extends axially through the shaft base 011. The connecting sleeve 012 is fixedly embedded in the hollow channel T, and the inner sidewall of the connecting sleeve 012 is provided with an internal spline. The connecting sleeve 012 is connected to the transmission component through the internal spline.

[0083] The density of the shaft base 011 can be less than the density of the connecting sleeve 012. The strength of the connecting sleeve 012 can be greater than the strength of the shaft base 011, and the hardness of the connecting sleeve 012 can be greater than the hardness of the shaft base 011. For example, the shaft base 011 is a shaft structure made of cast iron, and the connecting sleeve 012 is a sleeve structure made of steel.

[0084] The shaft base 011 includes a first shaft segment 0111, a second shaft segment 0112, and a third shaft segment 0113 connected sequentially in the axial direction. The outer diameters of the first shaft segment 0111 and the third shaft segment 0113 are both smaller than the outer diameter of the second shaft segment 0112.

[0085] The hollow channel T has an embedded groove C1 on its inner wall. A portion of the embedded groove C1 is located on the inner wall of the second shaft segment 0112, and another portion is located on the inner wall of the first shaft segment 0111. The axial length of the embedded groove C1 located on the inner wall of the second shaft segment 0112 is greater than the axial length of the embedded groove C1 located on the inner wall of the first shaft segment 0111.

[0086] The wall thickness of the connecting sleeve 012 is greater than the groove depth of the embedded groove C1, and part of the connecting sleeve 012 is fixed in the embedded groove C1 and is tightly connected to the groove surface of the embedded groove C1.

[0087] The outer wall of the connecting sleeve 012 is provided with multiple protrusions B. The multiple protrusions B are distributed at intervals in the outer circumferential direction of the connecting sleeve 012. The embedding groove C1 located on the inner wall of the second shaft segment 0112 is provided with multiple auxiliary reinforcing grooves C2. The multiple auxiliary reinforcing grooves C2 correspond one-to-one with the multiple protrusions B. Each protrusion B is embedded and fixed in the corresponding auxiliary reinforcing groove C2 and is tightly connected to the groove surface of the corresponding auxiliary reinforcing groove C2.

[0088] The connecting sleeve 012 has two axially oriented end faces, namely a first end face M1 and a second end face M2. The first end face M1 is located within the hollow channel T of the first shaft segment 0111, and the second end face M2 is located within the hollow channel T of the second shaft segment 0112. The connecting sleeve 012 has multiple protrusions B on its outer periphery near the second end face M2. The side of each protrusion B facing away from the first end face M1 can be flush with the second end face M2 of the connecting sleeve 012. Furthermore, the protrusions B embedded in the auxiliary reinforcing groove C2 can be spaced apart on the side near the first shaft segment 0111 and the side of the second shaft segment 0112 near the first shaft segment 0111. Thus, the protrusions B have a certain thickness of second shaft segment 0112 on both sides in the axial direction, ensuring that the rotor shaft 010 has good structural strength.

[0089] In summary, this application divides the rotor shaft of the motor rotor into two parts: the shaft base and the connecting sleeve. Since the connecting sleeve connects to the transmission components, to ensure the output torque of the connecting sleeve, its strength and hardness are set to be relatively high, so that the connecting sleeve can output a certain torque. The shaft base, on the other hand, is made of a material with relatively lower strength and hardness to reduce the cost of the rotor shaft, thereby reducing the cost of the motor rotor including the rotor shaft. Furthermore, the density of the shaft base is lower than that of the connecting sleeve, thus reducing the weight of the shaft base within the same volume, and consequently reducing the weight of the motor rotor including the rotor shaft. In addition, the independent design of the shaft base and connecting sleeve allows for flexible material selection based on usage and design requirements, giving the rotor shaft greater design flexibility.

[0090] Another embodiment of this application provides a drive motor, including: a motor stator and a motor rotor 000 as described in any of the above embodiments.

[0091] For example, the drive motor may also include: an end cover, a bearing, and a motor housing.

[0092] The motor stator is fixed to the inner wall of the motor housing.

[0093] The motor rotor 000 is fitted inside the motor stator, and the two ends of the rotor shaft 010 in the motor rotor 000 are fixed to the end covers at both ends of the motor housing by bearings.

[0094] The rotor shaft 010 can be connected to the external spline on the power input shaft in the reducer via the internal spline on the inner spline on the inner connecting sleeve 012 of the shaft base 011, so as to output torque to the reducer.

[0095] Since the drive motor in this embodiment includes the motor rotor 000 from the above embodiments, the weight and cost of the drive motor including the motor rotor 000 from the above embodiments can also be reduced when the weight and cost of the motor rotor 000 in the above embodiments are reduced. This solves the problems of large drive motor weight and high cost, and facilitates the development of drive motors towards high performance, lightweight, and low cost.

[0096] Another embodiment of this application provides a vehicle, including: a drive motor as described in the above embodiment.

[0097] For example, the vehicle may also include: a motor control module, an inverter, a reducer, a drive shaft, a differential, wheel axles, and wheels.

[0098] The motor control module serves as the control center of the entire vehicle, receiving and scheduling commands, and precisely sending control signals such as speed and torque to the inverter.

[0099] Inverters are used to convert the DC power from the power battery into three-phase AC power to supply the drive motor.

[0100] The drive motor is used to convert electrical energy into rotational mechanical energy and output torque and speed to the reducer through the rotor shaft 010.

[0101] The speed reducer is used to reduce the speed of the drive motor and amplify the output torque to match the current driving conditions of the vehicle.

[0102] The drive shaft is used to smoothly transmit the power output from the reducer to the differential.

[0103] The differential is used to distribute power to the left and right wheels, allowing the wheels on both sides of the vehicle to rotate at different speeds when turning, thus preventing dragging and slipping.

[0104] The wheel axle is used to receive the power from the differential and transmit that power to the wheels.

[0105] Wheels are used to propel a vehicle to normal movement by transmitting power through the wheel axle.

[0106] Since the vehicle in this application embodiment includes the drive motor in the above embodiment, the vehicle including the drive motor can also achieve the effect of reducing weight and cost when the weight and cost of the drive motor are reduced in the above embodiment.

[0107] When the overall weight of a vehicle can be reduced, the drag coefficient decreases, thereby reducing energy consumption and increasing driving range. Furthermore, reduced vehicle weight decreases inertia, making the vehicle more responsive during deceleration and acceleration, resulting in faster power response. In addition, reduced vehicle weight lowers manufacturing costs, thus enhancing product pricing competitiveness. The vehicle described in this application, through lightweight and low-cost design, facilitates cost reduction and efficiency improvement, large-scale mass production, and lower energy consumption, making it easier to meet energy efficiency requirements.

[0108] In this application, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance. The term "multiple" refers to two or more unless otherwise expressly defined.

[0109] The above description is merely an optional embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A motor rotor, characterized in that, include: Rotor shaft (010) and rotor magnetic circuit assembly (020); The rotor shaft (010) includes: a shaft base (011) and a connecting sleeve (012); the connecting sleeve (012) is coaxially arranged and fixedly connected to the shaft base (011), and the connecting sleeve (012) is used to connect with the transmission component; The rotor magnetic circuit assembly (020) is sleeved on the outside of the shaft base (011); The density of the shaft base (011) is less than the density of the connecting sleeve (012); the strength of the connecting sleeve (012) is greater than the strength of the shaft base (011), and the hardness of the connecting sleeve (012) is greater than the hardness of the shaft base (011).

2. The motor rotor according to claim 1, characterized in that, The shaft base (011) is provided with a hollow channel (T) that extends axially through the shaft base (011); the connecting sleeve (012) is fixedly embedded in the hollow channel (T); The inner wall of the connecting sleeve (012) is provided with an internal spline, and the connecting sleeve (012) is connected to the transmission component through the internal spline.

3. The motor rotor according to claim 2, characterized in that, The hollow channel (T) has an embedded groove (C1) on its inner wall; at least a portion of the connecting sleeve (012) is fixed in the embedded groove (C1) and is tightly connected to the groove surface of the embedded groove (C1).

4. The motor rotor according to claim 3, characterized in that, The wall thickness of the connecting sleeve (012) is greater than or equal to the groove depth of the embedded groove (C1).

5. The motor rotor according to claim 3, characterized in that, The outer wall of the connecting sleeve (012) is provided with a plurality of protrusions (B); the plurality of protrusions (B) are spaced apart in the outer peripheral direction of the connecting sleeve (012); The embedded groove (C1) is provided with a plurality of auxiliary reinforcing grooves (C2), and the plurality of auxiliary reinforcing grooves (C2) correspond one-to-one with the plurality of protrusions (B). Each protrusion (B) is embedded and fixed in the corresponding auxiliary reinforcing groove (C2) and is tightly connected to the groove surface of the corresponding auxiliary reinforcing groove (C2).

6. The motor rotor according to claim 5, characterized in that, The shaft base (011) includes: a first shaft segment (0111), a second shaft segment (0112), and a third shaft segment (0113) connected sequentially in the axial direction; the outer diameters of the first shaft segment (0111) and the third shaft segment (0113) are both smaller than the outer diameter of the second shaft segment (0112); the rotor magnetic circuit assembly (020) is sleeved on the outside of the second shaft segment (0112); A portion of the embedding groove (C1) is located on the inner wall of the second shaft segment (0112), and another portion is located on the inner wall of the first shaft segment (0111); the axial length of the embedding groove (C1) located on the inner wall of the second shaft segment (0112) is greater than or equal to the axial length of the embedding groove (C1) located on the inner wall of the first shaft segment (0111); the embedding groove (C1) located on the inner wall of the second shaft segment (0112) is provided with a plurality of auxiliary reinforcing grooves (C2).

7. The motor rotor according to claim 1, characterized in that, The connecting sleeve (012) is fixedly sleeved on the outside of the shaft base (011), and the outer side wall of the connecting sleeve (012) is provided with an external spline. The connecting sleeve (012) is connected to the transmission component through the external spline.

8. The motor rotor according to any one of claims 1-7, characterized in that, The shaft base (011) is a shaft structure made of cast iron, and / or the connecting sleeve (012) is a sleeve structure made of steel.

9. A drive motor, characterized in that, include: The motor stator and the motor rotor as described in any one of claims 1-8.

10. A vehicle, characterized in that, Includes the drive motor as described in claim 9.

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