Rotor core, rotor assembly, and motor

Abstract

The application discloses a rotor core, a rotor assembly and a motor, wherein the rotor core comprises a plurality of core units arranged around a rotation axis of the rotor core, one of the core units is a first core unit, and the first core unit is disconnected with other core units in the circumferential direction of the rotation axis; the first core unit comprises a plurality of laminated laminations arranged in the direction parallel to the rotation axis, one of the laminations is a first lamination, and the first lamination comprises a first side edge arranged towards the rotation axis; the first lamination is provided with a first through hole penetrating through the first side edge, and the first through hole is arranged without affecting the distribution of a rotor permanent magnetic field and can suppress an armature magnetic field. The suppression of the armature magnetic field can suppress high-frequency electromagnetic radial force and further suppress high-frequency noise. Moreover, the above-mentioned noise suppression process will not excessively affect the rotor permanent magnetic field, so that the performance of the motor will not be excessively weakened.

Description

Technical Field

[0001] This invention relates to the technical field of electric motors, and particularly to a rotor core, rotor assembly, and electric motor. Background Technology

[0002] Permanent magnet synchronous motors (PMSMs) have high power and torque densities and are widely used in household appliances. Motor performance and noise levels are crucial factors determining product quality. In PSMs, the interaction between the armature magnetic field and the rotor's permanent magnet magnetic field generates a high electromagnetic radial force. This causes radial vibration in the rotor during rotation, leading to high-frequency noise under high harmonic currents. Summary of the Invention

[0003] The main objective of this invention is to provide a rotor core, rotor assembly, and motor that can alleviate the high-frequency noise generated during motor operation.

[0004] To achieve the above objectives, an embodiment of the first aspect of the present invention provides a rotor core comprising a plurality of core units arranged around the rotation axis of the rotor core, wherein one of the core units is a first core unit, and the first core unit is disconnected from the other core units along the circumferential direction of the rotation axis.

[0005] The first core unit includes a plurality of stacked laminations arranged in a direction parallel to the rotation axis, one of which is a first stacked lamination, and the first stacked lamination includes a first side facing the rotation axis.

[0006] The first stacked sheet is provided with a first through hole, which penetrates the first side.

[0007] In some embodiments, along the radial direction perpendicular to the rotation axis, the maximum size L1 of the first stack and the maximum size L2 of the first through hole satisfy: 0.6 ≤ L2 / L1 < 1.

[0008] In some embodiments, the first stack includes a second side disposed away from the axis of rotation, and the minimum distance H1 between the inner wall of the first through hole and the second side satisfies: H1≥0.5mm.

[0009] In some embodiments, the first stacked plates are arranged symmetrically about a first plane, the rotation axis is located in the first plane, and the first through hole is arranged symmetrically about the first plane.

[0010] In some embodiments, the first through hole includes a first hole segment and a second hole segment connecting the first hole segment. The first hole segment is located on the side of the second hole segment away from the rotation axis, and the second hole segment passes through the first side. With the rotation axis as the center, the central angle α corresponding to the first hole segment and the central angle β corresponding to the second hole segment satisfy: 0.05≤β / α≤1.

[0011] Along the radial direction perpendicular to the rotation axis, the maximum size L1 of the first stack and the maximum size L3 of the first hole segment satisfy: 0.15≤L3 / L1≤0.45; or, along the radial direction perpendicular to the rotation axis, the maximum size L1 of the first stack and the maximum size L4 of the second hole segment satisfy: 0.2≤L4 / L1≤0.7.

[0012] In some embodiments, with the rotation axis as the center, the central angle γ corresponding to the first stacked sheet satisfies: 0.2≤α / γ≤0.5.

[0013] In some embodiments, the first side is provided with a first opening, and the first through hole penetrates the first side at the first opening along a direction perpendicular to the rotation axis. The minimum size H2 of the first opening satisfies: H2≥0.5mm.

[0014] In some embodiments, the laminations of the first core unit have the same shape and structure.

[0015] In some embodiments, the number of laminations in the first core unit is an even number N, and at least N / 2 of the laminations have the same shape as the first lamination.

[0016] In some embodiments, the number of laminations in the first core unit is an odd number M, and at least (M-1) / 2 of the laminations have the same shape as the first lamination.

[0017] In some embodiments, each of the core units is disconnected from each other, each of the core units has the same shape and structure, and each of the core units is arranged in a circular array with the rotation axis as the central axis.

[0018] In some embodiments, the other of each of the core units is a second core unit, the second core unit including a second lamination, the second lamination including a third side and a fourth side arranged circumferentially opposite each other along the rotation axis;

[0019] The third side is provided with a second opening at one end near the rotation axis, and the second stacked plate is provided with a second through hole, which penetrates the third side at the second opening.

[0020] In some embodiments, the second stack includes a fifth side facing the rotation axis, and along a radial direction perpendicular to the rotation axis, the maximum dimension L5 of the first stack and the maximum dimension L6 of the distance between the second opening and the fifth side satisfy: 0.02≤L6 / L5≤0.35.

[0021] A second aspect of the present invention also provides a rotor assembly, comprising:

[0022] The rotor core described in any of the above items;

[0023] Multiple permanent magnets, with a accommodating space defined between each two adjacent core units, and at least one permanent magnet is provided in each accommodating space;

[0024] A rotating shaft is disposed at the middle of the rotor core, and the axis of the rotating shaft coincides with the axis of rotation; and,

[0025] A cladding layer is applied to the outside of the rotor core and fills the gap between the rotor core and the shaft. The cladding layer connects the shaft and the rotor core respectively.

[0026] A third aspect of the present invention also provides a motor, comprising:

[0027] The rotor assembly of claim 12; and,

[0028] Stator assembly.

[0029] Compared with the prior art, the beneficial effects of the present invention are:

[0030] In the technical solution of this invention, the rotor core includes multiple core units, one of which is a first core unit. Along the circumferential direction of the rotation axis, the first core unit is disconnected from the other core units. At least one lamination of the first core unit (i.e., the first lamination) is provided with a first through hole, which penetrates the side of the first lamination near the rotation axis (i.e., the first side). Since the permanent magnet magnetic field of the rotor is distributed along the D-axis of the motor, and the armature magnetic field is distributed along the D-axis and Q-axis of the motor (the D-axis and Q-axis are perpendicular), when the first through hole penetrates the first side of the first lamination near the rotation axis, the first through hole can extend substantially towards the direction of the rotation axis. This ensures that the arrangement of the first through hole does not affect the distribution of the rotor's permanent magnet magnetic field and can suppress the armature magnetic field. The high-frequency radial force is generated by the interaction between the rotor's permanent magnet magnetic field and the armature magnetic field; therefore, suppressing the armature magnetic field can suppress the high-frequency electromagnetic radial force, thereby suppressing high-frequency noise. Furthermore, the above-mentioned noise suppression process does not significantly affect the rotor's permanent magnet magnetic field, thus not excessively weakening the motor's performance. Attached Figure Description

[0031] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0032] Figure 1 This is a cross-sectional view of the assembly of the rotor core and permanent magnet combined in one embodiment of the present invention, cut along a direction perpendicular to the rotation axis.

[0033] Figure 2 for Figure 1 A magnified view of a portion of point A in the middle;

[0034] Figure 3 This is a side view of the rotor core in the first embodiment of the present invention, viewed in a direction parallel to the axis of rotation;

[0035] Figure 4 This is a first side view schematic diagram of the first stack of sheets in the first embodiment of the present invention;

[0036] Figure 5 This is a second side view schematic diagram of the first stack of sheets in the first embodiment of the present invention;

[0037] Figure 6 This is a third side view schematic diagram of the first stack of sheets in the first embodiment of the present invention;

[0038] Figure 7 This is a side view of the first stack of sheets in the second embodiment of the present invention;

[0039] Figure 8 This is a side view of the first stack of sheets in the third embodiment of the present invention;

[0040] Figure 9 This is a side view of the first stack of sheets in the fourth embodiment of the present invention;

[0041] Figure 10 This is a side view of the first stack of sheets in the fifth embodiment of the present invention;

[0042] Figure 11 This is a side view of the first stack of sheets in the sixth embodiment of the present invention;

[0043] Figure 12 This is a side view of the first stack of sheets in the seventh embodiment of the present invention;

[0044] Figure 13 This is a side view of the first stack of sheets in the eighth embodiment of the present invention;

[0045] Figure 14This is a three-dimensional schematic diagram of the first iron core unit in the first embodiment of the present invention;

[0046] Figure 15 This is a three-dimensional schematic diagram of the first iron core unit in the second embodiment of the present invention;

[0047] Figure 16 This is a three-dimensional schematic diagram of the first iron core unit in the third embodiment of the present invention;

[0048] Figure 17 This is a first side view schematic diagram of the second stack of sheets in the first embodiment of the present invention;

[0049] Figure 18 This is a second side view schematic diagram of the second stack of sheets in the first embodiment of the present invention;

[0050] Figure 19 This is a side view of the rotor core in the second embodiment of the present invention, viewed in a direction parallel to the axis of rotation;

[0051] Figure 20 This is a side view of the rotor core in the third embodiment of the present invention, viewed in a direction parallel to the axis of rotation;

[0052] Figure 21 This is a side view of the rotor core in the fourth embodiment of the present invention, viewed in a direction parallel to the axis of rotation.

[0053] Explanation of icon numbers:

[0054] 10 - Rotor core;

[0055] 100 - Core unit; 100a - First core unit; 100b - Second core unit;

[0056] 110 - stacked film; 110a - first stacked film; 110b - second stacked film;

[0057] 111a - First side; 112a - Second side; 113a - First opening; 114a - First through hole;

[0058] 1141a - First borehole section; 1142a - Second borehole section;

[0059] 111b - Third side; 112b - Fourth side; 113b - Fifth side; 114b - Sixth side;

[0060] 115b - Second opening; 116b - Second through hole;

[0061] P1 - First plane;

[0062] 200-Permanent magnet;

[0063] 300-accommodation space.

[0064] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0065] 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 a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0066] It should be noted that if the embodiments of the present invention involve directional indications (such as up, down, left, right, front, back, etc.), the directional indications are only used to explain the relative positional relationship and movement of the components in a specific posture. If the specific posture changes, the directional indications will also change accordingly.

[0067] Furthermore, if the embodiments of this invention involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the use of "and / or," "and / or," or "and / or" throughout the text implies three parallel solutions. For example, "A and / or B" includes solution A, solution B, or a solution where both A and B are satisfied simultaneously. Furthermore, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this invention.

[0068] Permanent magnet synchronous motors (PMSMs) have high power and torque densities and are widely used in household appliances. Motor performance and noise levels are crucial factors determining product quality. In PSMs, the interaction between the armature magnetic field and the rotor's permanent magnet magnetic field generates a high electromagnetic radial force. This causes radial vibration in the rotor during rotation, leading to high-frequency noise under high harmonic currents.

[0069] In view of this, see Figures 1-21 One embodiment of this application provides a rotor core 10, which is used in a rotor assembly, and the rotor assembly is used in a motor. See also Figures 1-6In this embodiment, the rotor core 10 includes multiple core units 100, which are circumferentially distributed along the rotation axis (specifically, they can be arranged at equal intervals). A receiving space 300 for accommodating a permanent magnet 200 is defined between each two adjacent core units 100, and at least one permanent magnet 200 can be arranged in each receiving space 300. The rotation axis is the central axis of the rotor core 10. As the rotor core 10 within the rotor assembly, the rotation axis of the rotor core 10 coincides with the axis of rotation of the rotor assembly. When the rotor assembly rotates, the rotor core 10 rotates around the rotation axis.

[0070] For example, see Figures 1-3 In this embodiment, the rotor core 10 has eight core units 100, which together define eight accommodating spaces 300. This requires the rotor assembly with the rotor core 10 to have eight permanent magnets 200, each corresponding to one of the eight accommodating spaces 300. When each permanent magnet 200 is positioned within its respective accommodating space 300, two core units 100 can be tightly fitted to both sides of each permanent magnet 200, and two permanent magnets 200 can be tightly fitted to both sides of each core unit 100. This allows the permanent magnets 200 to position the relative positions of two adjacent core units 100, and the core units 100 to position the relative positions of two adjacent permanent magnets 200. In another embodiment, the permanent magnets 200 and core units 100 can be spaced apart, with other materials filling the space between them. This fixes the relative positions of both the permanent magnets 200 and the core units 100. In another embodiment, each accommodating space 300 may also contain a plurality of permanent magnets 200.

[0071] It should be noted that the boundary of the "accommodating space 300" in this application is defined by the arrangement position of the permanent magnet 200. In other words, when the permanent magnet 200 is arranged between two core units 100, the boundary of the permanent magnet 200 is the boundary of the accommodating space 300. For example, when the permanent magnet 200 is arranged between two core units 100, the end face of the permanent magnet 200 facing the rotation axis is the end face of the accommodating space 300 facing the rotation axis, the end face of the permanent magnet 200 away from the rotation axis is the end face of the accommodating space 300 away from the rotation axis, and the maximum radial dimension of the permanent magnet 200 along the rotor assembly is the maximum radial dimension of the accommodating space 300 along the rotor assembly.

[0072] The core units 100 in the rotor core 10 can be connected to or disconnected from each other. In this embodiment of the invention, at least one core unit 100 is disconnected from other core units 100. For example, see... Figures 1-3In this embodiment, each core unit 100 is arranged disconnected from each other. See also Figures 19-21 In this embodiment, some core units 100 are connected to each other, while each core unit 100 in another part is disconnected from all other core units 100. For ease of description, the core unit 100 that is disconnected from all other core units 100 is referred to as the first core unit 100a.

[0073] The first core unit 100a includes a plurality of laminations 110 stacked in a direction parallel to the rotation axis. Similarly, other core units 100 may also have a plurality of laminations 110 stacked in a direction parallel to the rotation axis, and the number of laminations 110 in each core unit 100 may be exactly the same. For ease of description, one of the laminations 110 in the first core unit 100a will be referred to as the first lamination 110a.

[0074] See Figures 2-4 In this embodiment, the first lamination 110a includes a first side 111a facing the rotation axis, and the first lamination 110a is provided with a first through hole 114a, which penetrates the first side 111a. Specifically, the first side 111a is provided with a first opening 113a, and the first through hole 114a penetrates the first side 111a at the first opening 113a. In this scheme, since the permanent magnet magnetic field of the rotor is distributed along the D-axis of the motor, and the armature magnetic field is distributed along the D-axis and Q-axis of the motor, with the D-axis and Q-axis perpendicular, when the first through hole 114a penetrates the first side 111a of the first lamination 110a near the rotation axis, the first through hole 114a can extend substantially towards the direction of the rotation axis. This allows the setting of the first through hole 114a to neither affect the distribution of the rotor's permanent magnet magnetic field nor suppress the armature magnetic field. The high-frequency radial force is generated by the interaction between the rotor's permanent magnet magnetic field and the armature magnetic field; therefore, suppressing the armature magnetic field can suppress the high-frequency electromagnetic radial force, thereby suppressing high-frequency noise. Furthermore, the aforementioned noise suppression process will not have too much impact on the rotor's permanent magnet magnetic field, thus not excessively weakening the motor's performance.

[0075] See Figures 4-6In some embodiments, the maximum size of the first lamination 110a is defined as L1 along the radial direction perpendicular to the rotation axis, and the maximum size of the first through hole 114a is defined as L2. The applicant considers that the maximum size L2 of the first through hole 114a is related to its effect on suppressing the armature magnetic field; when the maximum size L2 of the first through hole 114a is larger, the effect of the first through hole 114a in suppressing the armature magnetic field is better. Therefore, in order to improve the suppression effect of the first through hole 114a on the armature magnetic field, in this embodiment, the maximum size L1 of the first lamination 110a and the maximum size L2 of the first through hole 114a satisfy: 0.6 ≤ L2 / L1 < 1. For example, L2 / L1 can specifically be 0.6, 0.7, 0.8, 0.9, 0.92, or 0.95, etc. It has been demonstrated that when 0.6 ≤ L2 / L1 < 1, the suppression effect of the first through hole 114a on the armature magnetic field is better, thereby resulting in better noise suppression.

[0076] When the length of the first through-hole 114a is large along the radial direction perpendicular to the rotation axis, the overall integrity of the first lamination 110a is weak, and the integrity of the two parts of the first lamination 110a located on both sides of the first through-hole 114a is not high. When the length of the first through-hole 114a is small, the suppression effect of the first through-hole 114a on the armature magnetic field is poor. Therefore, it is necessary to increase the length of the first through-hole 114a while ensuring high integrity of the first lamination 110a. In view of this, see... Figures 3-4 In some embodiments, the first stack 110a includes a second side 112a disposed opposite to the rotation axis, and the second side 112a is arranged opposite to the first side 111a. The minimum distance H1 between the inner wall of the first through hole 114a and the second side 112a satisfies: H1 ≥ 0.5 mm. For example, H1 can be 0.5 mm, 0.6 mm, 1 mm, 1.5 mm, or 2 mm, etc. When H1 ≥ 0.5 mm, the first stack 110a can be guaranteed to have a certain degree of integrity, and the portions of the first stack 110a located on both sides of the first through hole 114a will not separate from each other. At the same time, it can also facilitate the processing of the first through hole 114a, reduce the processing accuracy requirements of the processing equipment, and reduce equipment costs and processing difficulty.

[0077] The specific shape, structure, and arrangement of the first through hole 114a depend on actual requirements. See [link / reference] Figure 7 In some embodiments, the first through hole 114a may be a straight hole, extending along a straight direction and perpendicular to the aforementioned straight direction, and the first through hole 114a is configured with a substantially uniform width. See also Figure 8 In some embodiments, the first through hole 114a is arranged in an inclined direction, and the axis of the first through hole 114a parallel to the direction of the first lamination 110a is not in the same plane as the rotation axis. See also Figures 6-7 In some embodiments, the axis of the first through hole 114a, parallel to the direction of the first stack 110a, intersects the rotation axis. See also Figure 6 -as well as Figure 7 In some embodiments, the first lamination 110a is arranged symmetrically about the first plane, the axis of rotation is located within the first plane P1, and the first through hole 114a is arranged symmetrically about the first plane P1. When the first through hole 114a is arranged symmetrically about the first plane P1, it is easier to design and manufacture the first lamination 110a, and the design and manufacturing costs of the first lamination 110a are reduced.

[0078] The first lamination 110a may have one first through hole 114a and one first opening 113a, or it may have multiple first through holes 114a and multiple first openings 113a. See also Figure 9 In some embodiments, the first side 111a is provided with a plurality of first openings 113a, and the first laminate 110a is provided with a plurality of first through holes 114a, each first through hole 114a corresponding to and communicating with each first opening 113a. See also Figures 6-8 In some embodiments, the first side 111a is provided with a first opening 113a, and the first stack 110a is provided with a first through hole 114a, the first through hole 114a communicating with the first opening 113a.

[0079] See Figures 4-6In some embodiments, the first through hole 114a includes a first hole segment 1141a and a second hole segment 1142a communicating with the first hole segment 1141a. The first hole segment 1141a is located on the side of the second hole segment 1142a away from the rotation axis, and the second hole segment 1142a communicates with the first opening 113a (i.e., the second hole segment 1142a penetrates the first side 111a). Furthermore, with the rotation axis as the center, the central angle corresponding to the first hole segment 1141a is defined as α, and the central angle corresponding to the second hole segment 1142a is defined as β. The central angle α corresponding to the first hole segment 1141a and the central angle β corresponding to the second hole segment 1142a satisfy: 0.05 ≤ β / α ≤ 1. For example, β / α can be 0.05, 0.1, 0.3, 0.5, 0.7, 0.9, or 1, etc. Along the radial direction perpendicular to the rotation axis, the maximum dimension of the first hole segment 1141a is defined as L3, and the maximum dimension of the second hole segment 1142a is defined as L4. In some embodiments, the maximum dimension L1 of the first stack 110a and the maximum dimension L3 of the first hole segment 1141a satisfy: 0.15 ≤ L3 / L1 ≤ 0.45. Exemplarily, L3 / L1 can be 0.15, 0.25, 0.35, or 0.45, etc. In other embodiments, the maximum dimension L1 of the first stack 110a and the maximum dimension L4 of the second hole segment 1142a satisfy: 0.2 ≤ L4 / L1 ≤ 0.7. Exemplarily, L4 / L1 can be 0.2, 0.3, 0.4, 0.5, 0.6, or 0.7, etc. In the above scheme, the circumferential width of the hole segment 114a away from the rotation axis (i.e., the second hole segment 1142a) is relatively large, and the circumferential width of the hole segment 114a close to the rotation axis (i.e., the first hole segment 1141a) is relatively small. This can match the actual size of the first lamination 110a, so that the first lamination 110a can have high strength and stiffness at all points along the radial direction, while not affecting the magnetic saturation of the permanent magnet magnetic field, and can better suppress the armature magnetic field.

[0080] The central angle α corresponding to the first hole segment 1141a is defined as follows (see below). Figures 3-5 Along the circumference of the rotation axis, the first hole segment 1141a has two opposite ends. Two straight lines passing through and perpendicular to the rotation axis are drawn, and each of these two lines is tangent to one of the aforementioned ends. The angle between the two lines is the central angle α corresponding to the first hole segment 1141a. Similarly, the definition of "the central angle β corresponding to the second hole segment 1142a" is the same as the definition of central angle α above, and will not be repeated here.

[0081] See Figures 3-5In some embodiments, with the rotation axis as the center, the central angle γ corresponding to the first lamination 110a satisfies: 0.2 ≤ α / γ ≤ 0.5. For example, α / γ can be 0.2, 0.3, 0.4, or 0.5, etc. This scheme can make reasonable use of the space of the first lamination 110a, without affecting the magnetic saturation of the permanent magnet magnetic field, and can better suppress the armature magnetic field. Similarly, the definition of "central angle γ corresponding to the first lamination 110a" is the same as the definition of the central angle α mentioned above, and will not be repeated here.

[0082] See Figure 2 as well as Figure 4 In some embodiments, the first side 111a is provided with a first opening 113a, and a first through hole 114a penetrates the first side 111a through the first opening 113a. Along a direction perpendicular to the rotation axis, the minimum dimension H2 of the first opening 113a satisfies: H2 ≥ 0.5 mm. For example, H2 can be 0.5 mm, 0.6 mm, 1 mm, 1.5 mm, or 2 mm, etc. This design facilitates the processing of the first opening 113a and reduces processing difficulty.

[0083] The shapes and structures of the laminations 110 within the first core unit 100a can be completely identical or partially identical. (See also...) Figure 1 , Figure 3 as well as Figure 14 In some embodiments, the laminations 110 of the first core unit 100a have the same shape and structure. That is, the shape of all laminations 110 within the first core unit 100a is the same as the shape of the first lamination 110a. This solution can reduce the processing difficulty of the laminations 110 and improve the processing efficiency of the laminations 110. Furthermore, when the shapes of all laminations 110 within the first core unit 100a are exactly the same, each first through hole 114a is aligned in a direction parallel to the rotation axis, and each first opening 113a is aligned in a direction parallel to the rotation axis, so that the first core unit 100a as a whole has a through groove extending in a direction parallel to the rotation axis. The integrity of the first core unit 100a is stronger, misalignment between the laminations 110 is less likely to occur, and assembly is also easier.

[0084] See Figures 15-16In other embodiments, the structures of the laminations 110 within the first core unit 100a are not entirely identical. Specifically, when the number of laminations 110 in the first core unit 100a is an even number N, at least N / a laminations 110 (including the first lamination 110a) have the same shape as the first lamination 110a. For example, when the first core unit 100a has twenty laminations 110, at least ten laminations 110 (including the first lamination 110a) have the same structure as the first lamination 110a. Alternatively, when the number of laminations 110 in the first core unit 100a is an odd number M, at least (M-1)² / a laminations 110 (including the first lamination 110a) have the same shape as the first lamination 110a. For example, when the first core unit 100a has twenty-one laminations 110, at least ten laminations 110 (including the first lamination 110a) have the same structure as the shape of the first lamination 110a.

[0085] When the shape of part of the stack 110 is the same as that of the first stack 110a, see Figure 15 In some embodiments, stacks 110 with the same shape as the first stack 110a can be stacked adjacent to each other, and stacks 110 with different shapes from the first stack 110a can be stacked adjacent to each other. See also Figure 16 In other embodiments, at least one stacked piece 110 with a different shape from the first stacked piece 110a may be provided between every two adjacent stacked pieces 110 with the same shape as the first stacked piece 110a, and the stacked pieces 110 with the same shape as the first stacked piece 110a and the stacked pieces 110 with a different shape from the first stacked piece 110a may be stacked alternately. Exemplarily, in some embodiments, the stacked pieces 110 with a different shape from the first stacked piece 110a are stacked with the first stacked piece 110a, and along a direction parallel to the rotation axis, the stacked pieces 110 with a different shape from the first stacked piece 110a cover the first through hole 114a. The stacked pieces 110 with a different shape from the first stacked piece 110a may not have the first through hole 114a, or the stacked pieces 110 with a different shape from the first stacked piece 110a may have the first through hole 114a, but their positions are staggered. In other embodiments, the stacked sheets 110 with the same shape as the first stacked sheet 110a and the stacked sheets 110 with different shapes from the first stacked sheet 110a may have other arrangements, which will not be elaborated here.

[0086] The structures of the multiple core units 100 in the rotor core 10 can be completely identical, partially identical, or completely different. See also Figures 1-3In some embodiments, all core units 100 have the same shape and structure, and are arranged in a circular array around the rotation axis. This arrangement facilitates the manufacturing of the rotor core 10 and reduces its manufacturing cost. In other embodiments, only some core units 100 may have the same shape as the first core unit 100a, while the other core units 100 may have different shapes.

[0087] In addition to the first through hole 114a, other through holes can also be provided on the first lamination 110a. See details... Figures 10-13 The end of the first laminate 110a facing away from the rotation axis is also provided with four through holes, and two of the aforementioned through holes are provided on each side of the first laminate 110a along the circumference around the rotation axis. See Figure 10 In some embodiments, all four through holes are isolated from the sides of the first stack 110a. See also Figure 11 In some embodiments, all four through holes extend through the second side 112a of the first laminate 110a. See also Figure 12 In some embodiments, the four through holes correspond to two opposing sides (the side between the first side 111a and the second side 112a) arranged circumferentially about the rotation axis of the first lamination 110a. See also Figure 13 In some embodiments, the four through holes both penetrate the second side 112a of the first stack 110a and correspondingly penetrate the two opposite sides of the first stack 110a arranged circumferentially around the rotation axis.

[0088] See Figures 17-21 In some embodiments, the other of each core unit 100 is a second core unit 100b, which is disconnected from the other core units 100. The second core unit 100b includes a second lamination 110b. The second lamination 110b includes a third side 111b and a fourth side 112b arranged circumferentially opposite each other along the rotation axis. The third side 111b has a second opening 115b at one end near the rotation axis, and the second lamination 110b has a second through hole 116b, which penetrates the third side 111b through the second opening 115b. In this scheme, since the second opening 115b of the second through hole 116b is located at the end of the third side 111b near the rotation axis, the second through hole 116b can also suppress the armature magnetic field without having too much influence on the rotor magnetic field, thereby suppressing the high-frequency noise of the rotor assembly without having too much influence on the rotor performance.

[0089] See Figures 17-18In some embodiments, the second lamination 110b includes a fifth side 113b facing the rotation axis. Along a radial direction perpendicular to the rotation axis, the maximum dimension L5 of the second lamination 110b and the maximum dimension L6 of the distance from the second opening 115b to the fifth side 113b satisfy: 0.02 ≤ L6 / L5 ≤ 0.35. Exemplarily, L6 / L5 can be 0.02, 0.05, 0.1, 0.2, 0.3, or 0.35, etc. When 0.02 ≤ L6 / L5 ≤ 0.35, the influence of the first through-hole 114a on the rotor magnetic field can be reduced, thereby reducing the impact on the performance of the rotor assembly.

[0090] Similarly, the shapes and structures of the laminations 110 within the second core unit 100b can be completely identical or partially identical. In some embodiments, the shapes and structures of the laminations 110 within the second core unit 100b are identical. That is, the shapes of all laminations 110 within the second core unit 100b are the same as the shape of the second lamination 110b. This approach reduces the processing difficulty of the second core unit 100b and improves its processing efficiency. Furthermore, when the shapes of all laminations 110 within the second core unit 100b are completely identical, each second through hole 116b is aligned in a direction parallel to the rotation axis, and each second opening 115b is aligned in a direction parallel to the rotation axis, resulting in the second core unit 100b having a through groove extending in a direction parallel to the rotation axis. This strengthens the integrity of the second core unit 100b, reduces the likelihood of misalignment between the laminations 110, and facilitates assembly.

[0091] In other embodiments, the structures of the laminations 110 within the second core unit 100b are not entirely identical. Specifically, when the number of laminations 110 in the second core unit 100b is an even number N, at least N / a laminations 110 (including the second lamination 110b) have the same shape as the second lamination 110b. For example, when the second core unit 100b has twenty laminations 110, at least ten laminations 110 (including the second lamination 110b) have the same structure as the second lamination 110b. Alternatively, when the number of laminations 110 in the second core unit 100b is an odd number M, at least (M-1)² / a laminations 110 (including the second lamination 110b) have the same shape as the second lamination 110b. For example, when the second core unit 100b has twenty-one laminations 110, at least ten laminations 110 (including the second lamination 110b) have the same structure as the shape of the second lamination 110b.

[0092] See Figures 17-18In some embodiments, along the radial direction perpendicular to the rotation axis, the maximum dimension L5 of the second lamination 110b and the maximum dimension L7 of the second through hole 116b satisfy: 0.6 ≤ L7 / L5 < 1. For example, L7 / L5 can specifically be 0.6, 0.7, 0.8, 0.9, 0.92, or 0.95, etc. It has been demonstrated that when 0.6 ≤ L7 / L5 < 1, the second through hole 116b has a better suppression effect on the armature magnetic field, thereby resulting in a better noise suppression effect.

[0093] See Figures 17-18 In some embodiments, the second stack 110b includes a sixth side 114b disposed opposite to the rotation axis, and the sixth side 114b is arranged opposite to the fifth side 113b. The minimum distance H3 between the inner wall of the second through hole 116b and the sixth side 114b satisfies: H3 ≥ 0.5mm. For example, H3 can be 0.5mm, 0.6mm, 1mm, 1.5mm, or 2mm, etc. When H3 ≥ 0.5mm, the second stack 110b can be guaranteed to have a certain degree of integrity, and the portions of the second stack 110b located on both sides of the second through hole 116b will not separate from each other. At the same time, it also facilitates the processing of the second through hole 116b, reduces the processing accuracy requirements of the processing equipment, and reduces equipment costs and processing difficulty.

[0094] See Figures 17-18 In some embodiments, the minimum dimension H4 of the second opening 115b along the direction perpendicular to the rotation axis satisfies: H4 ≥ 0.5 mm. For example, H4 can be 0.5 mm, 0.6 mm, 1 mm, 1.5 mm, or 2 mm, etc. This design facilitates the processing of the first opening 113a and reduces processing difficulty.

[0095] In some embodiments, the core units 100 within the rotor core 10 may be disconnected from each other. Further, the core units 100 within the rotor core 10 may have identical shapes and structures, and the core units 100 may be arranged in a circular array around the rotation axis. See also Figure 3 In some embodiments, the shape of each core unit 100 within the rotor core 10 is the same as the shape of the first core unit 100a.

[0096] In some embodiments, each core unit 100 within the rotor core 10 may be disconnected from each other, and a portion of the rotor core 10 may have the same shape as the first core unit 100a, while another portion of the rotor core 10 may have the same shape as the second core unit 100b.

[0097] See Figures 19-21In some embodiments, only some of the core units 100 may be disconnected from each other, while the ends of other core units 100 near the axis of rotation may be connected to each other. Furthermore, in some embodiments, each disconnected core unit 100 may have the same shape as the first core unit 100a. In other embodiments, each disconnected core unit 100 may have the same shape as the second core unit 100b. In still other embodiments, each disconnected core unit 100 may have a portion with the same shape as the first core unit 100a and another portion with the same shape as the second core unit 100b. Further, see... Figure 20 Core units 100 with the same shape as the first core unit 100a and core units 100 with the same shape as the second core unit 100b can be arranged adjacent to each other, together defining a receiving space 300 for accommodating the permanent magnet 200. See also Figure 21 The core unit 100 with the same shape as the first core unit 100a and the core unit 100 with the same shape as the second core unit 100b can also be arranged separately, with other core units 100 of different shapes provided between them.

[0098] A second aspect of the present invention also provides a rotor assembly comprising the rotor core 10 of any of the above embodiments, and further comprising a plurality of permanent magnets 200, a shaft, and a cladding layer. A receiving space 300 is defined between each pair of adjacent core units 100, and at least one permanent magnet 200 is disposed in each receiving space 300. The shaft is located at the center of the rotor core 10, and the axis of the shaft coincides with the rotation axis. In some embodiments, when the rotor cores 10 are arranged separately from each other, the cladding layer covers the outside of the rotor core 10 and fills the gap between the rotor core 10 and the shaft, and the cladding layer connects the shaft and the rotor core 10 respectively. The shaft may not be directly connected to each core unit 100, but may be indirectly connected through the cladding layer. In the specific processing, the relative positions between the rotating shaft and the rotor core 10 can be determined first. Then, an injection molding process is performed on the assembly of the two to form a coating layer. This coating layer covers the outer wall of the rotor core 10 and fills the gap between the rotating shaft and the rotor core 10, thereby achieving the purpose of fixing the rotating shaft and the rotor core 10. The coating layer can also protect the rotor core 10 and extend its service life.

[0099] A third aspect of the present invention provides an electric motor, which includes the rotor assembly and stator assembly of any of the above embodiments.

[0100] The above are merely preferred embodiments of the present invention and do not limit the patent scope of the present invention. All equivalent structural transformations made using the contents of the present invention specification and drawings under the inventive concept of the present invention, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present invention.

Claims

1. A rotor core, characterized in that, It includes multiple core units arranged around the rotation axis of the rotor core, one of which is a first core unit. Along the circumference of the rotation axis, the first core unit is disconnected from the other core units. The first core unit includes a plurality of stacked laminations arranged in a direction parallel to the rotation axis, one of which is a first stacked lamination, and the first stacked lamination includes a first side facing the rotation axis. The first stacked sheet is provided with a first through hole, which penetrates the first side; The other of each of the core units is a second core unit, which includes a second lamination, and the second lamination includes a third side and a fourth side arranged circumferentially opposite to each other along the rotation axis. The third side is provided with a second opening at one end near the rotation axis, and the second stacked plate is provided with a second through hole, which penetrates the third side at the second opening.

2. The rotor core as described in claim 1, characterized in that, Along the radial direction perpendicular to the axis of rotation, the maximum dimension L1 of the first stack and the maximum dimension L2 of the first through hole satisfy: 0.6 ≤ L2 / L1 < 1.

3. The rotor core as described in claim 1, characterized in that, The first stack includes a second side that is disposed away from the axis of rotation, and the minimum distance H1 between the inner wall of the first through hole and the second side satisfies: H1≥0.5mm.

4. The rotor core as described in claim 1, characterized in that, The first stacked plates are arranged symmetrically about the first plane, the rotation axis is located in the first plane, and the first through hole is arranged symmetrically about the first plane.

5. The rotor core as described in claim 1, characterized in that, The first through hole includes a first hole segment and a second hole segment connecting the first hole segment. The first hole segment is located on the side of the second hole segment away from the rotation axis. The second hole segment passes through the first side. With the rotation axis as the center, the central angle α corresponding to the first hole segment and the central angle β corresponding to the second hole segment satisfy: 0.05≤β / α≤1. Along the radial direction perpendicular to the rotation axis, the maximum size L1 of the first stack and the maximum size L3 of the first hole segment satisfy: 0.15≤L3 / L1≤0.45; or, along the radial direction perpendicular to the rotation axis, the maximum size L1 of the first stack and the maximum size L4 of the second hole segment satisfy: 0.2≤L4 / L1≤0.

7.

6. The rotor core as described in claim 5, characterized in that, With the rotation axis as the center, the central angle γ corresponding to the first stacked piece satisfies: 0.2≤α / γ≤0.

5.

7. The rotor core as described in claim 1, characterized in that, The first side has a first opening, and the first through hole penetrates the first side at the first opening. In a direction perpendicular to the rotation axis, the minimum size H2 of the first opening satisfies: H2≥0.5mm.

8. The rotor core as described in claim 1, characterized in that, The laminations of the first core unit have the same shape and structure; or, The number of laminations in the first core unit is an even number N, and at least N / 2 of the laminations have the same shape as the first lamination. or, The number of laminations in the first core unit is an odd number M, and at least (M-1) / 2 of the laminations have the same shape as the first lamination.

9. The rotor core as described in claim 1, characterized in that, Each of the core units is disconnected from each other, each of the core units has the same shape and structure, and each of the core units is arranged in a circular array with the rotation axis as the central axis.

10. The rotor core as described in claim 1, characterized in that, The second stack includes a fifth side facing the axis of rotation. Along a radial direction perpendicular to the axis of rotation, the maximum dimension L5 of the second stack and the maximum dimension L6 of the distance between the second opening and the fifth side satisfy: 0.02≤L6 / L5≤0.

35.

11. A rotor assembly, characterized in that, include: The rotor core according to any one of claims 1-10; Multiple permanent magnets, with a accommodating space defined between each two adjacent core units, and at least one permanent magnet is provided in each accommodating space; A rotating shaft is located in the middle of the rotor core, and the axis of the rotating shaft coincides with the axis of rotation. as well as, A cladding layer is applied to the outside of the rotor core and fills the gap between the rotor core and the shaft. The cladding layer connects the shaft and the rotor core respectively.

12. An electric motor, characterized in that, include: The rotor assembly as claimed in claim 11; as well as, Stator assembly.

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