Motor rotor assembly and motor

Abstract

The invention relates to the technical field of motors, in particular to a motor rotor assembly and a motor. The motor rotor assembly comprises a rotor iron core which is provided with a plurality of mounting grooves along the circumferential direction; the motor shaft penetrates through the rotor iron core and is fixed with the rotor iron core; the balance disc is arranged on the motor shaft and is pressed on the end surfaces of the two ends of the rotor iron core along the axial direction; the magnetic steel is mounted in the mounting groove; and the injection molding part is provided with an embedded part and an exposed part which are connected, the embedded part is positioned in the mounting groove and fills a gap between the magnetic steel and the groove wall of the mounting groove, and the exposed part extends out of the mounting groove and is pressed on the end surfaces of the two axial ends of the rotor iron core. The exposed part can replace part of the balance disc, so that the size of the balance disc is reduced, and the raw material cost is reduced; the exposed part is connected with the embedded part which is mounted in the mounting groove and can fix the magnetic steel, so that the structural strength of the exposed part is ensured, the exposed part is not easy to fall off, the balance performance of the motor rotor is ensured, the motor rotor is simple and convenient to assemble, and the production cost is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of motors, and particularly to a motor rotor assembly and a motor. Background Art

[0002] With the rapid development of new energy vehicles, new energy vehicles have higher requirements for the rotational speed and use environment of motors. Especially when the motor rotor rotates at high speed, higher requirements are imposed on the balance of the motor rotor. At present, some balance the motor rotor by installing a balance disk on the motor rotor. However, the general balance disk is usually an aluminum balance disk, which is expensive and brings great cost pressure, making the product lose competitiveness in the market. Others balance the motor rotor by installing a large cover plate and a balance disk on the motor rotor, which is not only costly but also very inconvenient for assembly production. Summary of the Invention

[0003] In view of the above-mentioned disadvantages of the prior art, the purpose of the present invention is to provide a motor rotor assembly and a motor, which are used to solve the problems of difficult assembly and high cost of the rotor balance assembly of the motor in the prior art.

[0004] To achieve the above object and other related objects, the present invention provides a motor rotor assembly, including:

[0005] A rotor core, on which a plurality of installation grooves are circumferentially arranged;

[0006] A motor shaft, which passes through the rotor core and is fixed to the rotor core;

[0007] A balance disk, which is installed on the motor shaft and presses on the end faces of both axial ends of the rotor core;

[0008] Magnets, which are installed in the installation grooves;

[0009] An injection molding part, which has a connected embedded part and an exposed part. The embedded part is located in the installation groove and fills the gap between the magnet and the groove wall of the installation groove. The exposed part extends out of the installation groove and presses on the end faces of both axial ends of the rotor core.

[0010] Optionally, the rotor core includes a plurality of silicon steel sheets stacked axially. Slots are provided on each of the silicon steel sheets and the magnets are installed. The slots of each of the silicon steel sheets are axially communicated to form the installation groove.

[0011] Optionally, the embedded part is located in the slot, the exposed part extends out of the slot, and presses on the end faces of the silicon steel sheets located at both ends in the stacking direction of the plurality of silicon steel sheets.

[0012] Optionally, in the stacking direction of the plurality of silicon steel sheets, the slots on the silicon steel sheets at both ends include a plastic injection channel section and an installation section where the magnet is installed. The installation section and the plastic injection channel section are distributed and communicated along the length direction of the magnet. The plastic injection part includes a thermosetting material filling body. The first part of the plastic injection part is filled in the installation section and cured to form the embedded part, and the second part of the plastic injection part is filled in the plastic injection channel section and extends from the plastic injection channel section to the end face of the silicon steel sheet and is cured to form the exposed part.

[0013] Optionally, the cross-section of the exposed part is similar to the cross-section of the plastic injection channel section, and the height H of the exposed part protruding from the end face of the silicon steel sheet satisfies 0.5mm ≤ H ≤ 2.5mm.

[0014] Optionally, the installation groove has a proximal end close to the center of the rotor core and a distal end far from the center of the rotor core. The exposed part is arranged at the distal end of the installation groove; alternatively, the exposed part is arranged at the distal end and the proximal end of the installation groove.

[0015] Optionally, the exposed part arranged at the distal end of the installation groove extends along the end face of the rotor core and is connected to another exposed part located at the distal end of the adjacent installation groove as a whole.

[0016] Optionally, every two symmetrically arranged installation grooves form an installation groove pair. One installation groove pair or a plurality of installation groove pairs distributed along the radial direction of the rotor core form an installation groove group. The number of installation groove groups is multiple, and the multiple installation groove groups are evenly distributed along the circumferential direction of the rotor core and are located on the outer periphery of the balance disk.

[0017] Optionally, the distance between the proximal ends of the two installation grooves in the same installation groove pair is smaller than the distance between the distal ends of the two installation grooves.

[0018] Optionally, every two symmetrically arranged magnets installed on the same silicon steel sheet form a magnet pair. The magnet has a proximal end close to the center of the rotor core and a distal end far from the center of the rotor core along its length direction. The distance between the proximal ends of the two magnets in the same magnet pair is smaller than the distance between the distal ends of the two magnets.

[0019] Optionally, one magnet pair or a plurality of magnet pairs distributed along the radial direction of the rotor core form a magnet group. The number of magnet groups is multiple, and the multiple magnet groups are evenly distributed along the circumferential direction of the rotor core, and the magnet group and the exposed part are located on the outer periphery of the balance disk.

[0020] Optionally, the contact width between the exposed part and the end face of the rotor core is W, where 0.2 mm ≤ W ≤ 1.5 mm.

[0021] To achieve the above object and other related objects, the present application further provides a motor, including the motor rotor assembly as described above.

[0022] As described above, the motor rotor assembly and the motor of the present invention at least have the following beneficial effects: The exposed part cooperates with the balance disk to press the end faces of both ends of the rotor core. The exposed part can replace part of the balance disk, which is beneficial to reducing the size of the balance disk and eliminating the need to set additional components such as steel sleeves or cover plates, thus helping to reduce the raw material cost. Based on this, the exposed part is connected to the embedded part that is installed in the installation groove and can fix the permanent magnet. On the one hand, it ensures the structural strength of the exposed part and is not easy to fall off, thereby ensuring the balance performance of the motor rotor. On the other hand, it simplifies the structure, and the assembly is simple and convenient, which is beneficial to reducing the production cost. Description of the Drawings

[0023] Figure 1 Showing the structural schematic diagram of the first embodiment of the motor rotor assembly of the present invention;

[0024] Figure 2 Showing Figure 1 The partial structural schematic diagram of the injection molded part in

[0025] Figure 3 Showing Figure 1 The partial structural schematic diagram of the rotor core before installing the permanent magnet and the injection molded part in

[0026] Figure 4 Showing Figure 1 The partial structural schematic diagram of the rotor core after installing the permanent magnet and the injection molded part in

[0027] Figure 5 Showing Figure 1 The side view of the partial structure of the motor rotor assembly in

[0028] Figure 6 Showing Figure 1 The top view of the motor rotor assembly in

[0029] Figure 7 Showing Figure 6 The cross-sectional view at A-A in

[0030] Figure 8 Showing Figure 1 The bottom view of the motor rotor assembly in

[0031] Figure 9 Showing Figure 8 The enlarged schematic diagram of the partial B in

[0032] Figure 10 It shows a schematic structural view of the permanent magnet of the first embodiment of the motor rotor assembly of the present invention;

[0033] Figure 11 It shows a partial top view of the permanent magnet group located on the same silicon steel sheet of the first embodiment of the motor rotor assembly of the present invention;

[0034] Figure 12 It shows a partial structural view of the rotor core of the second embodiment of the motor rotor assembly of the present invention before installing the permanent magnet and the injection molded part;

[0035] Figure 13 It shows a partial structural view of the rotor core of the third embodiment of the motor rotor assembly of the present invention before installing the permanent magnet and the injection molded part;

[0036] Figure 14 It shows a partial structural view of the rotor core of the fourth embodiment of the motor rotor assembly of the present invention before installing the permanent magnet and the injection molded part.

[0037] Description of part numbers

[0038] Rotor core 1, mounting groove 11, slot 111, mounting section 112, injection plastic channel section 113, silicon steel sheet 12, mounting groove pair 13, mounting groove group 14, motor shaft 2, balance disk 3, permanent magnet group 4, permanent magnet pair 41, permanent magnet 411, injection molded part 5, embedded part 51, exposed part 52, first exposed part 521, second exposed part 522, third exposed part 523, fourth exposed part 524. Detailed implementation manners

[0039] The following uses specific specific examples to illustrate the implementation manners of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through different specific implementation manners. Various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention.

[0040] It should be noted that the illustrations provided in this embodiment only schematically illustrate the basic concept of the present invention. Therefore, only the components related to the present invention are shown in the drawings, rather than being drawn according to the number, shape, and size of the components in actual implementation. The type, quantity, and ratio of each component in actual implementation can be arbitrarily changed, and the layout type of its components may also be more complex. The structures, ratios, sizes, etc. shown in the drawings of this specification are only used to cooperate with the content disclosed in the specification for those familiar with this technology to understand and read, and are not used to limit the limiting conditions under which the present invention can be implemented. Therefore, they do not have technical essence. Any modification of the structure, change of the proportional relationship, or adjustment of the size, without affecting the effects that the present invention can produce and the purposes that can be achieved, should still fall within the scope covered by the technical content disclosed in the present invention. At the same time, the terms such as "upper", "lower", "left", "right", "middle", and "one" cited in this specification are only for the convenience of clear description and are not used to limit the scope under which the present invention can be implemented. The change or adjustment of their relative relationship, without substantial change in the technical content, should also be regarded as the scope under which the present invention can be implemented.

[0041] See Figures 1 to 5 and Figure 10 , in some alternative embodiments, the present application provides a motor rotor assembly, which includes a rotor core 1, a motor shaft 2, a balance disk 3, a permanent magnet 411, and an injection molding part 5. A plurality of mounting grooves 11 are circumferentially arranged on the rotor core 1; the motor shaft 2 passes through the rotor core 1 and is fixed to the rotor core 1, and the rotor core 1 and the motor shaft 2 can rotate together; the balance disk 3 is mounted on the motor shaft 2 and presses on the end faces of both axial ends of the rotor core 1 to prevent the end faces of the rotor core 1 from warping and affecting the balance performance of the rotor core 1. The balance disk 3, the motor shaft 2, and the rotor core 1 can rotate together; the permanent magnet 411 is mounted in the mounting groove 11; the injection molding part 5 has a connected embedded part 51 and an exposed part 52. The embedded part 51 is located in the mounting groove 11 and fills the gap between the permanent magnet 411 and the groove wall of the mounting groove 11 to fix the permanent magnet 411, and the exposed part 52 extends out of the mounting groove 11 and presses on the end faces of both axial ends of the rotor core 1.

[0042] Optionally, the injection molding part 5 includes a thermosetting material filling body, or rather, the injection molding part 5 is made of a thermosetting material. Further, the thermosetting material includes thermosetting resins such as epoxy resin or unsaturated polyester resin. The injection molding part 5 is integrally injection molded, which is not only stable and reliable in structure, but also convenient for production and assembly, and is beneficial to reducing production costs.

[0043] Optionally, the embedded part 51 of the injection molded part 5 at least covers part of the magnet 411, so that the magnet 411 can be stably installed in the installation groove 11, the magnet 411 is not easy to shake, and the structure is stable and reliable. Further, the magnet 411 is completely covered by the embedded part 51, that is to say, the surface of the magnet 411 is covered with the embedded part 51; wherein, the magnet 411 can be in the shape of a cuboid, and has an in-center end close to the center of the rotor core 1 and an out-center end far from the rotor core 1 along its length direction.

[0044] Optionally, the axis lines of the rotor core 1, the balance disk 3 and the motor shaft 2 coincide.

[0045] Optionally, the balance disk 3 is pressed against the position on the end face of the rotor core 1 close to the center of the rotor core 1, and the exposed part 52 is located on the outer periphery of the balance disk 3, so that the exposed part 52 and the balance disk 3 cooperate to press against different positions on the end face of the rotor core 1 to reduce the risk of warping of the end face of the rotor core 1.

[0046] In the motor rotor assembly of the above embodiment, the exposed part 52 and the balance disk 3 cooperate to press against different positions on the end face of the rotor core 1 to prevent the end face of the rotor core 1 from warping, so as to ensure the balance of the rotor core 1. The position pressed by the exposed part 52 does not need to be pressed by the balance disk 3 anymore, which is beneficial to reducing the size of the balance disk 3 and reducing the cost of raw materials; in addition, the exposed part 52 and the embedded part 51 located in the installation groove 11 are connected as a whole, ensuring the strength of the exposed part 52. Even under the conditions of high-speed rotation of the rotor core 1 and oil fluid scouring, the exposed part 52 is not easy to fall off from the rotor core 1 and can stably press on the end face of the rotor core 1.

[0047] See Figure 1 、 Figures 3 to 9 , in some alternative embodiments, the rotor core 1 includes a plurality of silicon steel sheets 12 stacked along the axial direction of the rotor core 1. Slots 111 are provided on each silicon steel sheet 12 and magnets 411 are installed. The slots 111 of each silicon steel sheet 12 are axially connected to form an installation groove 11. The embedded parts 51 of the same injection molded part 5 are distributed in the slots 111 that make up the same installation groove 11 to fixedly install the magnets 411 in each slot 111.

[0048] Optionally, the embedded part 51 is located in the slot 111, and the exposed part 52 extends out of the slot 111 and presses against the end faces of the silicon steel sheets 12 at both ends along the stacking direction of the plurality of silicon steel sheets 12. The exposed part 52 pressing against the end faces of the silicon steel sheets 12 at the ends is beneficial to preventing the silicon steel sheets 12 from warping, especially effectively preventing the silicon steel sheets 12 at the ends from warping during transfer magnetization and high-speed operation, ensuring the balance of the rotor core 1.

[0049] Optionally, in the stacking direction of multiple silicon steel sheets 12, the slots 111 on the silicon steel sheets 12 at both ends include a plastic injection channel section 113 and an installation section 112 where the magnet 411 is installed. The installation section 112 and the plastic injection channel section 113 are distributed and communicated along the length direction of the magnet 411. The first part of the injection molded part 5 is filled in the installation section 112 and cured to form an embedded part 51, and the second part of the injection molded part 5 is filled in the plastic injection channel section 113 and extends from the plastic injection channel section 113 to the end face of the silicon steel sheet 12 and is cured to form an exposed part 52. Among them, at least one end of the slot 111 of the silicon steel sheet 12 at the end is provided with a plastic injection channel section 113. Specifically, the slot 111 has a proximal end close to the center of the rotor core 1 and a distal end far from the center of the rotor core 1 along its length direction. In this embodiment, the length direction of the slot 111 can be the same as the length direction of the magnet 411. A plastic injection channel section 113 is provided at one end of the slot 111 far from the center of the rotor core 1 or plastic injection channel sections 113 are provided at both ends of the slot 111. The setting of the plastic injection channel section 113 is beneficial to the flow and injection molding of thermosetting materials.

[0050] Optionally, refer to FIGS. 3 to Figure 5 , the cross-section of the exposed part 52 is similar to the cross-section of the plastic injection channel section 113, so that the exposed part 52 extends out of the rotor core 1 from the plastic injection channel section 113 and can be higher than the end face of the rotor core 1, which is beneficial to ensuring the feasibility of the injection molding process and the strength of the exposed part 52; the height of the exposed part 52 extending out of the end face of the silicon steel sheet 12 is H, and 0.5 mm ≤ H ≤ 2.5 mm, which is beneficial to further ensuring the feasibility of the injection molding process and the strength of the exposed part 52, and can keep pressing the end face of the silicon steel sheet 12 even under the action of oil fluid scouring and high-speed centrifugal force, and is not easy to fail; among them, the cross-section of the exposed part 52 is parallel to the end face of the rotor core 1. Further, H can be any value among 0.8 mm, 1 mm, 1.5 mm, 2.3 mm, etc.

[0051] Optionally, refer to Figure 9 , the contact width between the exposed part 52 and the end face of the rotor core 1 is W, and 0.2 mm ≤ W ≤ 1.5 mm. That is to say, the contact width between the exposed part 52 and the end face of the silicon steel sheet 12 at the end is W, which is beneficial to ensuring that the exposed part 52 fully presses on the end face of the silicon steel sheet 12, thereby preventing the silicon steel sheet 12 from warping. Further, W can be any value among 0.3 mm, 0.5 mm, 1 mm, 1.2 mm, etc.

[0052] Optionally, the installation groove 11 axially penetrates through the end faces of both ends of the rotor core 1 along the axial direction of the rotor core 1, that is to say, the installation groove 11 axially penetrates through a plurality of silicon steel sheets 12 along the axial direction of the rotor core 1, which is convenient for the integral injection molding of the injection molded part 5, with simple processing, enabling the embedded parts 51 in each slot 111 of the same installation groove 11 to be connected as a whole.

[0053] Specifically, during the production and assembly process, the magnet 411 is installed in the installation section 112 of the corresponding slot 111. A plurality of silicon steel sheets 12 are stacked and arranged such that a plurality of corresponding slots 111 communicate axially to form the installation groove 11. The thermosetting material filling body is injected through the gate of the injection mold. The thermosetting material filling body first reaches the end face of the first end of the rotor core 1, enters the installation section 112 from the injection plastic channel section 113 on the silicon steel sheet 12 at the first end of the rotor core 1, and sequentially flows into the slots 111 of each silicon steel sheet 12 until it reaches the installation section 112 on the silicon steel sheet 12 at the second end of the rotor core 1 and flows out from the injection plastic channel section 113 to the end face of the second end of the rotor core 1. After the thermosetting material filling body is cured, the embedded part 51 and the exposed part 52 are formed at the corresponding positions. The rotor core 1 designed with this structure is simple and convenient for processing, production, and assembly, which is beneficial to reducing costs in terms of materials and production processes.

[0054] For the motor rotor assembly of the above embodiment, the injection molded part 5 is simple to manufacture and has low cost. The injection molded part 5 is integrally formed, ensuring the reliability of the injection molded part 5 in a high-speed oil-cooled environment, thereby effectively preventing the end face of the rotor core 1 from warping, and further ensuring the balance of the rotor core 1.

[0055] See Figures 1 to 4 、 Figure 10 and Figure 11 , in some alternative embodiments, the installation groove 11 has a proximal end close to the center of the rotor core 1 and a distal end far from the center of the rotor core 1 along its length direction. The length direction of the installation groove 11 may be the same as the length direction of the slot 111, and the exposed part 52 is arranged at the distal end of the installation groove 11; or, the exposed part 52 is arranged at the distal end and the proximal end of the installation groove 11. Among them, the exposed part 52 corresponds to the injection plastic channel section 113.

[0056] Optionally, the exposed part 52 arranged at the distal end of the installation groove 11 extends along the end face of the rotor core 1 and is connected as a whole with another exposed part 52 at the distal end of the adjacent installation groove 11. Specifically, see Figure 2 and Figure 4, the multiple exposed parts 52 provided at the telecentric ends of the multiple mounting grooves 11 are respectively a first exposed part 521, a second exposed part 522, and a third exposed part 523. The adjacent first exposed part 521 and second exposed part 522 are connected as a whole or disconnected. The adjacent second exposed part 522 and third exposed part 523 are connected as a whole or disconnected. Or rather, only two adjacent ones, three adjacent ones, or all three of the first exposed part 521, the second exposed part 522, and the third exposed part 523 are connected, or all three are disconnected. It can be understood that the multiple exposed parts 52 are not limited to the quantity and connection modes exemplified above, and can be flexibly set according to requirements or the quantity and distribution of the mounting grooves 11. When two adjacent ones or all three of the first exposed part 521, the second exposed part 522, and the third exposed part 523 are connected, the layout is compact, and the connected exposed parts 52 can share the gate. For example, if the first exposed part 521 and the second exposed part 522 are connected, the gate can be shared, which is beneficial to saving the gate of the injection mold, improving the service life of the injection mold, and reducing costs. The risk of warping of the silicon steel sheet 12 at the position close to the center of the rotor core 1 is relatively lower than that at the position far from the center of the rotor core 1. The multiple exposed parts 52 provided at the centric ends of the multiple mounting grooves 11 are respectively fourth exposed parts 524. The fourth exposed parts 524 can be reduced or cancelled according to requirements, and the setting is flexible, so as to reduce costs while effectively preventing the silicon steel sheet 12 from warping.

[0057] Optionally, every two symmetrically arranged magnet pairs 411 mounted on the same silicon steel sheet 12 form a magnet pair 41. The magnet 411 has a centric end close to the center of the rotor core 1 and a telecentric end far from the center of the rotor core 1 along its length direction. The centric end of the magnet 411 corresponds to the centric end of the mounting groove 11, and the telecentric end of the magnet 411 corresponds to the telecentric end of the mounting groove 11. The distance D1 between the centric ends of the two magnets 411 of the same magnet pair 41 is less than the distance D2 between the telecentric ends of the two magnets 411. Specifically, the two magnets 411 of the same magnet pair 41 can be in an "eight" shape. Further, one magnet pair 41 or multiple magnet pairs 41 distributed radially along the rotor core 1 form a magnet group 4. That is to say, each magnet group 4 can include one magnet pair 41 or multiple magnet pairs 41. The number of magnet groups 4 is multiple, and the multiple magnet groups 4 are evenly distributed circumferentially along the rotor core 1, with a symmetrical structure. Moreover, the magnet groups 4 and the exposed parts 52 are both located on the outer periphery of the balance disk 3, which is beneficial to improving the balance of the rotor core 1.

[0058] For the motor rotor assembly of the above embodiment, at least the telecentric end of the mounting groove 11 is provided with an exposed part 52, with a stable structure, ensuring that the silicon steel sheet 12 at the end of the rotor core 1 is not prone to warping, thereby ensuring the balance of the motor rotor assembly.

[0059] See Figure 1 , Figure 3, Figures 11 to 14 , in some alternative embodiments, every two symmetrically arranged mounting grooves 11 form a mounting groove pair 13, and one mounting groove pair 13 or multiple mounting groove pairs 13 radially distributed along the rotor core 1 form a mounting groove group 14. That is to say, each mounting groove group 14 includes one mounting groove pair 13 or multiple mounting groove pairs 13. When including multiple mounting groove pairs 13, the multiple mounting groove pairs 13 are radially distributed along the rotor core 1. The number of mounting groove groups 14 is multiple, and the multiple mounting groove groups 14 are evenly distributed along the circumferential direction of the rotor core 1 and are located on the outer periphery of the balance disk 3. Among them, the number of mounting groove pairs 13 included in each mounting groove group 14 can be set according to requirements, and the distribution positions of the two magnets 411 of each magnet pair 41 correspond to the distribution positions of the two mounting grooves 11 of each mounting groove pair 13.

[0060] Optionally, the distance D3 between the proximal ends of the two mounting grooves 11 of the same mounting groove pair 13 is less than the distance D4 between the distal ends of the two mounting grooves 11. For example, the two mounting grooves 11 of the same mounting groove pair 13 can be in an "eight" shape. Further, the cross-sections of the two mounting grooves 11 of the same mounting groove pair 13 are the same, which is beneficial to improving the balance. It can be understood that the cross-section of the mounting section 112 of the mounting groove 11 can be square, fan-shaped or other shapes, and the specific shape can be flexibly set according to requirements; the shape of the cross-section of the injection molding channel section 113 can be flexibly set according to requirements. The cross-sections of the injection molding channel sections 113 at the proximal end and the distal end of the same mounting groove 11 can be the same or different, and the cross-sections of the injection molding channel sections 113 of the mounting grooves 11 of different mounting groove pairs 13 can be the same or different.

[0061] Optionally, referring to Figure 12 , each mounting groove group includes 1 mounting groove pair 13. Correspondingly, each magnet group includes 1 magnet pair.

[0062] Optionally, referring to Figure 13 , each mounting groove group 14 includes 2 mounting groove pairs 13. Correspondingly, each magnet group includes 2 magnet pairs.

[0063] Optionally, referring to Figure 3 , Figure 11 and Figure 14 , each mounting groove group includes 3 mounting groove pairs 13, and each magnet group 4 includes 3 magnet pairs 41.

[0064] For the motor rotor assembly of the above embodiment, the mounting grooves 11 are symmetrically arranged on the rotor core 1, with a symmetric structure and flexible settings. It can not only be flexibly adjusted according to requirements, but also improve the balance of the overall structure of the motor rotor assembly.

[0065] Referring to Figures 1 to 11, in some alternative embodiments, the present application further provides a motor, including the motor rotor assembly of any one of the above embodiments. Wherein, in addition to the motor rotor assembly, the motor further includes a stator.

[0066] For the motor rotor assembly and the motor of the present invention, by arranging the exposed portion 52 to press on the end face of the rotor core 1, it is beneficial to prevent the end face of the rotor core 1 from warping while reducing costs. Moreover, the exposed portion 52 is integrally connected to the embedded portion 51 that can fix the permanent magnet 411, which not only improves the structural strength of the exposed portion 52, but also facilitates integral injection molding, simplifies the production and assembly process, and reduces costs.

[0067] In the description of this specification, the descriptions referring to terms such as "this embodiment", "example", "specific example", etc. mean that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in a suitable manner in any one or more embodiments or examples.

[0068] The above embodiments are only illustrative of the principles and effects of the present invention, and are not used to limit the present invention. Any person familiar with this technology can modify or change the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or changes made by those with ordinary knowledge in the technical field without departing from the spirit and technical idea disclosed by the present invention should still be covered by the claims of the present invention.

Claims

1. A motor rotor assembly, characterized in that: include: A rotor core, wherein a plurality of mounting grooves are arranged on the rotor core along the circumferential direction; A motor shaft, the motor shaft passes through the rotor core and is fixed to the rotor core; A balancing disk, which is mounted on the motor shaft and pressed against end surfaces of both ends of the rotor core along the axial direction; A magnetic steel, the magnetic steel being installed in the installation groove; The injection molded part has an embedded part and an exposed part connected to each other, the embedded part is located in the mounting groove and fills the gap between the magnetic steel and the groove wall of the mounting groove, and the exposed part extends out of the mounting groove and is pressed on the end faces of the rotor core at both ends along the axial direction.

2. The motor rotor assembly according to claim 1, characterized in that: The rotor core comprises a plurality of silicon steel sheets stacked in an axial direction, each of the silicon steel sheets is provided with a slot and the magnetic steel is installed thereon, and the slots of each silicon steel sheet are axially connected to form the installation groove.

3. The motor rotor assembly according to claim 2, characterized in that: The embedded portion is located in the slot, and the exposed portion extends out of the slot and presses on the end surfaces of the silicon steel sheets located at both ends along the stacking direction of the plurality of silicon steel sheets.

4. The motor rotor assembly according to claim 2, characterized in that: In the stacking direction of the plurality of silicon steel sheets, the slots on the silicon steel sheets at both ends include an injection molded material channel section and an installation section on which the magnetic steel is installed, the installation section and the injection molded material channel section are distributed and connected along the length direction of the magnetic steel, the injection molded part includes a thermosetting material filling body, the first part of the injection molded part is filled in the installation section and solidified to form the embedded part, the second part of the injection molded part is filled in the injection molded material channel section and extends from the injection molded material channel section to the end face of the silicon steel sheet and solidified to form the exposed part.

5. The motor rotor assembly according to claim 4, characterized in that: The cross section of the exposed portion is similar to the cross section of the injection molding material channel section, and the height of the exposed portion extending out of the end surface of the silicon steel sheet is H, 0.5 mm≤H≤2.5 mm.

6. The motor rotor assembly according to claim 1, characterized in that: The mounting groove has a proximal end close to the center of the rotor core and a distal end away from the center of the rotor core, and the exposed portion is arranged at the distal end of the mounting groove; or, the exposed portion is arranged at the distal end of the mounting groove and the proximal end of the mounting groove.

7. The motor rotor assembly according to claim 6, characterized in that: The exposed portion disposed at the distal end of the mounting slot extends along the end surface of the rotor core and is integrally connected with another exposed portion located at the distal end of an adjacent mounting slot.

8. The motor rotor assembly according to claim 6, characterized in that: Every two symmetrically arranged mounting grooves form a mounting groove pair, one mounting groove pair or multiple mounting groove pairs distributed along the radial direction of the rotor core form a mounting groove group, the number of the mounting groove groups is multiple, and multiple mounting groove groups are evenly distributed along the circumference of the rotor core and located on the outer periphery of the balancing disk.

9. The motor rotor assembly according to claim 8, characterized in that: The distance between the proximal ends of the two mounting grooves of the same mounting groove pair is smaller than the distance between the distal ends of the two mounting grooves.

10. The motor rotor assembly according to claim 2, characterized in that: Every two symmetrically arranged magnetic steels mounted on the same silicon steel sheet form a magnetic steel pair, and the magnetic steel has a proximal end close to the center of the rotor core and a distal end far from the center of the rotor core along its length direction, and the distance between the proximal ends of the two magnetic steels of the same magnetic steel pair is smaller than the distance between the distal ends of the two magnetic steels.

11. The motor rotor assembly according to claim 10, characterized in that: One magnetic steel pair or multiple magnetic steel pairs distributed along the radial direction of the rotor core form a magnetic steel group. The number of the magnetic steel groups is multiple, and the multiple magnetic steel groups are evenly distributed along the circumference of the rotor core, and the magnetic steel groups and the exposed portions are located on the outer periphery of the balancing disk.

12. The motor rotor assembly according to claim 1, characterized in that: The contact width between the exposed portion and the end surface of the rotor core is W, and 0.2 mm ≤ W ≤ 1.5 mm.

13. A motor, characterized in that: The invention comprises a motor rotor assembly according to any one of claims 1 to 12.

Images