Rotor core body of motor, rotor assembly, motor and electric appliance

Abstract

The invention discloses a rotor core of a motor, a rotor assembly, a motor and an electric appliance, and belongs to the field of electrical equipment. The rotor core body of the motor comprises a supporting part; the plurality of tooth parts are distributed around the circumferential direction of the supporting part at intervals, rotor slots for mounting permanent magnets are formed between the adjacent tooth parts, and the tooth parts extend along the radial direction of the rotor core body; and the outer peripheral surface, along the radial direction of the rotor core body, of each tooth part comprises a plurality of wall surface sections which are sequentially connected in the circumferential direction of the rotor core body. According to the rotor core body of the motor provided by the invention, the plurality of wall surface sections are arranged on the outer peripheral surface of the tooth part of the rotor core body, so that the harmonic content of the motor can be reduced, the torque pulsation of the motor can be reduced, and the performance of the motor can be improved.

Description

Technical Field

[0001] The present application belongs to the technical field of electrical equipment, and in particular relates to a rotor core, a rotor assembly, a motor and an electrical appliance of a motor. Background Art

[0002] In current motor products, a rotor core is usually formed by a support portion and a plurality of teeth in a fan-shaped structure. However, this type of rotor core has a high harmonic content during operation, and the torque pulsation of the motor is high. Summary of the invention

[0003] The present application aims to solve at least one of the technical problems existing in the prior art. To this end, the present application proposes a rotor core, a rotor assembly, a motor and an electrical appliance of a motor, which can help reduce the harmonic content of the motor, help reduce the torque pulsation of the motor, and thus help improve the performance of the motor.

[0004] In a first aspect, the present application provides a rotor core of a motor, comprising:

[0005] Supporting part;

[0006] A plurality of tooth portions are spaced apart and distributed around the circumference of the support portion, rotor slots for mounting permanent magnets are formed between adjacent tooth portions, the tooth portions extend radially along the rotor core, and the radial outer peripheral surface of the tooth portions along the rotor core includes a plurality of wall segments connected sequentially around the circumference of the rotor core.

[0007] According to the rotor core of the motor provided in the embodiment of the present application, by providing a plurality of wall segments on the outer peripheral surface of the tooth portion of the rotor core, it can help reduce the harmonic content of the motor, help reduce the torque pulsation of the motor, and thus help improve the performance of the motor.

[0008] According to one embodiment of the present application, the support portion is connected to the tooth portion via a connecting portion, and an end of the connecting portion close to the tooth portion is provided with a positioning protrusion protruding circumferentially toward the rotor core, and the positioning protrusion defines the radial inner end of the rotor slot.

[0009] According to an embodiment of the present application, the outer peripheral wall of the support portion is provided with reinforcing ribs, and the reinforcing ribs protrude toward the rotor slots.

[0010] According to one embodiment of the present application, the distance between the reinforcing rib and the radial inner end of the rotor slot is A, satisfying: A ≥ 0.8 mm.

[0011] According to an embodiment of the present application, the support portion is connected to the tooth portion via a connecting portion, and a width of the connecting portion along the circumferential direction of the rotor core is H3, satisfying: 0.6 mm ≤ H3 ≤ 0.9 mm.

[0012] According to one embodiment of the present application, it further includes: a connecting bridge, through which the radial outer ends of two adjacent teeth are connected.

[0013] According to one embodiment of the present application, the thickness of the connecting bridge along the axial direction of the rotor core is H2, satisfying: 0.5mm≤H2≤3mm.

[0014] According to one embodiment of the present application, the outer circumferential surface of the support portion includes a first wall segment, a second wall segment and a third wall segment, and the first wall segment, the second wall segment and the third wall segment are all arcs with the center of curvature facing the inside of the rotor core.

[0015] According to one embodiment of the present application, the following conditions are met:

[0016] Wherein R1 is the radius of the second wall segment, and R2 is the radius of the first wall segment and the third wall segment.

[0017] According to one embodiment of the present application, the following conditions are met:

[0018] C1 is the circumferential length of the outer circumference of the tooth portion around the rotor core, S1 is the distance from the center of the first wall segment and the third wall segment to the symmetry plane of the tooth portion, S2 is the distance from the center of the first wall segment and the third wall segment to the first center plane, the axis of the rotor core is located on the first center plane, and the first center plane is perpendicular to the symmetry plane of the tooth portion.

[0019] According to one embodiment of the present application, the outer circumferential surface of the support portion includes a first straight line segment, a second arc segment, a third arc segment, a fourth arc segment and a fifth straight line segment, and the second arc segment, the third arc segment and the fourth arc segment are all circular arcs with the center of curvature facing the inside of the rotor core.

[0020] According to one embodiment of the present application, the following conditions are met:

[0021] 0.5mm≤H1≤1.5mm, wherein r1 is the radius of the third arc segment, R3 is the radius of the second arc segment and the fourth arc segment, H1 is the radial distance between the first straight line segment and the fifth straight line segment and the vertex of the third arc segment, C2 is the circumferential length of the outer circumferential surface of the support portion around the rotor core, S3 is the distance from the center of the second arc segment and the fourth arc segment to the symmetry plane of the tooth portion, S4 is the distance from the center of the second arc segment and the fourth arc segment to the first center plane, the axis of the rotor core is located on the first center plane, and the first center plane is perpendicular to the symmetry plane of the tooth portion.

[0022] According to one embodiment of the present application, the axial height of the rotor core is H4, which satisfies: 9mm≤H4≤21mm.

[0023] In a second aspect, the present application provides a rotor assembly of a motor, the rotor assembly of the motor comprising:

[0024] The rotor core of the motor as described in any one of the above, wherein the support portion has a central hole;

[0025] A permanent magnet, the permanent magnet being mounted on the rotor core;

[0026] A motor shaft is mounted in the center hole.

[0027] According to the rotor assembly of the motor provided in the embodiment of the present application, by adopting the rotor core of any of the above embodiments, the harmonic content of the motor can be reduced, the torque pulsation of the motor can be reduced, and thus the performance of the motor can be improved.

[0028] In a third aspect, the present application provides a motor, comprising:

[0029] A rotor assembly of a motor as described in any one of the above;

[0030] The stator assembly is installed outside the rotor assembly.

[0031] According to the motor of the embodiment of the present application, by leading the lead wires of the stator assembly out from the lower end surface of the stator assembly, the motor can be installed in a designated installation position when the radial space is small, thereby expanding the application range of the motor.

[0032] In a fourth aspect, the present application provides an electrical appliance, the electrical appliance comprising:

[0033] power supply;

[0034] For the motor as described in any one of the above, the input end of the motor is electrically connected to the power supply.

[0035] According to the electrical appliance of the embodiments of the present application, by adopting the motor of any of the above embodiments, the motor can be installed in a designated installation position when the radial space is small, thereby reducing the overall volume and occupied space of the electrical appliance.

[0036] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0038] Figure 1 It is one of the structural schematic diagrams of the rotor core of the motor provided in the embodiment of the present application;

[0039] Figure 2 This is the second structural schematic diagram of the rotor core of the motor provided in the embodiment of the present application;

[0040] Figure 3 This is the third structural schematic diagram of the rotor core of the motor provided in the embodiment of the present application;

[0041] Figure 4 This is the fourth structural schematic diagram of the rotor core of the motor provided in the embodiment of the present application;

[0042] Figure 5 yes Figure 4 A partial enlarged view in FIG.

[0043] Figure 6 This is the fifth structural schematic diagram of the rotor core of the motor provided in the embodiment of the present application;

[0044] Figure 7 yes Figure 6 A partial enlarged view of B;

[0045] Figure 8 is a schematic diagram of the structure of the motor provided in an embodiment of the present application;

[0046] Fig. 9 is a schematic diagram of a partial structure of a motor provided in an embodiment of the present application;

[0047] Fig.10 is a schematic structural diagram of a stator assembly of a motor provided in an embodiment of the present application;

[0048] Fig.11 is a schematic structural diagram of an end cover of a motor provided in an embodiment of the present application;

[0049] Fig.12 is a back electromotive force data diagram of a comparative example;

[0050] Fig.13 is one of the back electromotive force data diagrams of the motor having the rotor assembly provided by the embodiment of the present application;

[0051] Fig.14 This is the second back-electromotive force data diagram of the motor having the rotor assembly provided in the embodiment of the present application.

[0052] Reference numerals:

[0053] Rotor core 100, support portion 110, reinforcing rib 111, center hole 112, connection portion 120, positioning protrusion 121, tooth portion 130, rotor slot 131, first wall segment 132, second wall segment 133, third wall segment 134, first straight segment 135, second arc segment 136, third arc segment 137, fourth arc segment 138, fifth straight segment 139, connection bridge 140, motor shaft 150, and retaining pin 151;

[0054] Stator assembly 200, stator core 210, winding slot 211, inner circumferential wall 220, notch 221, lead wire 230;

[0055] End cover 300, cover body 310, first section 311, second section 312, bearing chamber 320, tube body 321, first flange 322, second flange 323;

[0056] Bearing 400 and gasket 500 . DETAILED DESCRIPTION

[0057] The embodiments of the present application are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present application, and cannot be understood as limiting the present application.

[0058] Reference below Figure 1-Figure 11 The rotor core 100 , the rotor assembly, the motor, and the electrical machine according to the embodiments of the present application are described.

[0059] The present application provides a rotor core 100 of a motor, such as Figure 1-Figure 7 As shown, the rotor core 100 of the motor includes a support portion 110 and a plurality of teeth portions 130 .

[0060] Among them, Figure 1-Figure 4 , Figure 6 As shown, the support portion 110 may be a columnar structure, the cross section of the support portion 110 may be circular, and the end surface of the support portion 110 may be uniformly provided with a plurality of openings spaced apart along the circumferential direction. For example, the end surface of the support portion 110 may be uniformly provided with 10 openings spaced apart along the circumferential direction.

[0061] like Figure 1-Figure 4 , Figure 6 As shown, a plurality of teeth 130 are distributed around the circumference of the support portion 110 at intervals. The teeth 130 may be in a fan-shaped structure. The number of teeth 130 may be 20, 16 or any other number of teeth 130.

[0062] like Figure 1-Figure 4 , Figure 6As shown, rotor slots 131 for mounting permanent magnets are formed between adjacent tooth portions 130, the tooth portions 130 extend radially along the rotor core 100, and tooth boots protruding along the circumferential direction are provided on both sides of the radial outer ends of the tooth portions 130, and rotor slots 131 for mounting permanent magnets are formed on the opposite sides of two adjacent tooth portions 130 and on the inner wall surfaces of the tooth boots on the opposite sides of two adjacent tooth portions 130.

[0063] like Figure 1-Figure 4 , Figure 6 As shown, when there are 20 teeth 130, 20 rotor slots 131 are formed between adjacent teeth 130, that is, 20 permanent magnets are installed in the 20 rotor slots 131 in a one-to-one correspondence; when there are 16 teeth 130, 16 rotor slots 131 are formed between adjacent teeth 130, that is, 16 permanent magnets are installed in the 16 rotor slots 131 in a one-to-one correspondence, which can form better magnetic potential and electric potential waveforms to improve the performance of the motor.

[0064] like Figure 1-Figure 4 , Figure 6 As shown, the tooth portion 130 along the radial outer peripheral surface of the rotor core 100 includes a plurality of wall segments connected sequentially around the circumference of the rotor core 100. For example, the tooth portion 130 along the radial outer peripheral surface of the rotor core 100 includes 3, 5 or other number of wall segments. The plurality of wall segments may include one or more combinations of arc segments, straight line segments or other shapes of wall segments. When the plurality of wall segments are all arc segments, the diameters and center positions of the plurality of arc segments may be different.

[0065] According to the rotor core 100 of the motor provided in the embodiment of the present application, by providing a plurality of wall segments on the outer peripheral surface of the tooth portion 130 of the rotor core 100, it can help reduce the harmonic content of the motor, help reduce the torque pulsation of the motor, and thus help improve the performance of the motor.

[0066] In some embodiments, Figure 1-Figure 4 , Figure 6 As shown, the support portion 110 is connected to the tooth portion 130 via the connecting portion 120 , and one end of the connecting portion 120 close to the tooth portion 130 is provided with a positioning protrusion 121 protruding toward the circumferential direction of the rotor core 100 , and the positioning protrusion 121 defines the radial inner end of the rotor slot 131 .

[0067] like Figure 1-Figure 4 , Figure 6 As shown, the cross-section of the connecting portion 120 may be rectangular, elliptical or other shaped structures, one end of the connecting portion 120 is connected to the radial outer side of the supporting portion 110 , and the other end of the connecting portion 120 is connected to the radial inner side of the tooth portion 130 .

[0068] like Figure 1-Figure 4 , Figure 6As shown, the support portion 110, the connection portion 120 and the tooth portion 130 can be made in an integrated manner, or the support portion 110, the connection portion 120 and the tooth portion 130 can be made separately and then connected together by bonding, threading or other means.

[0069] like Figure 1-Figure 4 , Figure 6 As shown, one end of the connecting portion 120 connected to the tooth portion 130 is provided with a positioning protrusion 121 protruding outward in the circumferential direction. The connecting portion 120 can be provided with the positioning protrusion 121 on both circumferential sides of the rotor core 100, or can be provided with the positioning protrusion 121 on one side of the rotor core 100 in the circumferential direction.

[0070] like Figure 1-Figure 4 , Figure 6 As shown, the radial outer side surface of the positioning protrusion 121 on the rotor core 100, the opposite sides of two adjacent teeth 130 and the radial inner side surface of the tooth shoe on the rotor core 100 cooperate to form a rotor slot 131, and the permanent magnet is set to a shape structure matching the rotor slot 131.

[0071] In actual implementation, when assembling the permanent magnet, since the positioning protrusion 121 is provided, the permanent magnet can be directly inserted into the rotor slot 131 for installation and fixation.

[0072] In the related art, since a gap needs to be set between the permanent magnet and the support part 110, when installing the permanent magnet, the position of the permanent magnet is usually limited by a three-point positioning method. However, the error of the three-point positioning method is large, which can easily lead to a large difference between the actual installation position of the permanent magnet and the target installation position. The rotor core 100 provided in the embodiment of the present application limits the position of the permanent magnet by a positioning protrusion 121, that is, the distance between each permanent magnet and the support part 110 is fixed under the action of the positioning protrusion 121.

[0073] By disposing the positioning protrusion 121, the permanent magnet can be positioned to avoid the influence on the magnetic field caused by excessive deviation of the installation positions of multiple permanent magnets.

[0074] In some embodiments, Figure 1-Figure 4 , Figure 6 As shown, the outer peripheral wall of the support portion 110 is provided with a reinforcing rib 111 , and the reinforcing rib 111 protrudes toward the rotor slot 131 .

[0075] Among them, Figure 1-Figure 4 , Figure 6 As shown, the cross-section of the reinforcing rib 111 can be rectangular, elliptical or other shapes. One end of the reinforcing rib 111 is connected to the support portion 110 , and the other end of the reinforcing rib 111 protrudes outward along the radial direction of the support portion 110 .

[0076] like Figure 1-Figure 4 , Figure 6 As shown, there may be one or more reinforcing ribs 111 , and the plurality of reinforcing ribs 111 are evenly arranged on the outer peripheral wall of the supporting portion 110 along the circumference of the supporting portion 110 to ensure the balance of the supporting portion 110 .

[0077] like Figure 1-Figure 4 , Figure 6 As shown, the number of the reinforcing ribs 111 may be equal to the number of the rotor slots 131 , and the plurality of reinforcing ribs 111 are located in the plurality of rotor slots 131 in a one-to-one correspondence, so as to set a maximum number of reinforcing ribs 111 without affecting the magnetic field.

[0078] By disposing the reinforcing ribs 111 , the strength of the rotor core 100 during subsequent overmolding can be enhanced, so as to reduce shrinkage and deformation of the rotor core 100 during overmolding.

[0079] In some embodiments, the distance between the reinforcing rib 111 and the radial inner end of the rotor slot 131 is A, satisfying: A ≥ 0.8 mm.

[0080] Among them, there is a certain gap between the positioning protrusions 121 on opposite sides of two adjacent connecting parts 120, and the reinforcing rib 111 is arranged toward the gap between the two positioning protrusions 121. At this time, the reinforcing rib 111 has a certain distance from the radial inner end of the rotor slot 131, that is, the end of the reinforcing rib 111 away from the supporting part 110 has a certain distance from the radial inner end surface of the permanent magnet installed in the rotor slot 131, and the distance is A, and A≥0.8mm.

[0081] By setting the distance between the reinforcing rib 111 and the radial inner end of the rotor slot 131, it is possible to avoid excessive magnetic leakage caused by the permanent magnet installed in the rotor slot 131 contacting the reinforcing rib 111. At the same time, injection molding space can be reserved for the injection molded parts when the permanent magnet and the rotor core 100 are subsequently injection molded and fixed.

[0082] In some embodiments, Figure 1 As shown, the support portion 110 is connected to the tooth portion 130 via the connecting portion 120 , and the width of the connecting portion 120 along the circumferential direction of the rotor core 100 is H3 , satisfying: 0.6 mm ≤ H3 ≤ 0.9 mm.

[0083] like Figure 1 As shown, the connection portion 120 connects the support portion 110 and the tooth portion 130 into a whole having sufficient mechanical strength, and can limit the leakage magnetic flux of the permanent magnet by saturating the leakage magnetic flux of the connection portion 120 .

[0084] By limiting the circumferential width of the connecting portion 120 along the rotor core 100 to between 0.6 mm and 0.9 mm, the effect of the connecting portion 120 in limiting the leakage flux of the permanent magnet can be ensured, while avoiding the connection portion 120 being too small, which would lead to a reduction in the mechanical strength of the tooth portion 130 and thus a reduction in service life, so as to further reduce leakage flux and improve motor efficiency.

[0085] In some embodiments, Figure 1-Figure 4 , Figure 6 As shown, the rotor core 100 of the motor further includes a connecting bridge 140 , and radial outer ends of two adjacent tooth portions 130 are connected via the connecting bridge 140 .

[0086] Among them, Figure 1-Figure 4 , Figure 6 As shown, the tooth boots of two adjacent tooth portions 130 located on opposite sides are connected via a connecting bridge 140 , and the connecting bridge 140 may be a rectangular structure, an arc structure or other shapes.

[0087] like Figure 1-Figure 4 , Figure 6 As shown, the connection bridges 140 are provided at two axial ends of the rotor core 100 , that is, each tooth shoe is connected to adjacent tooth shoes at two axial ends of the rotor core 100 through two connection bridges 140 .

[0088] By disposing the connecting bridge 140 , two adjacent teeth 130 can be connected as a whole, thereby improving the mechanical strength of the teeth 130 and reducing the deformation of the teeth 130 in subsequent processes.

[0089] In some embodiments, Figure 3 As shown, the thickness of the connecting bridge 140 along the axial direction of the rotor core 100 is H2, which satisfies: 0.5 mm≤H2≤3 mm.

[0090] If the axial thickness H2 of the connecting bridge 140 along the rotor core 100 is too large, it will easily lead to waste of magnetic flux and waste of material of the connecting bridge 140; if the axial thickness H2 of the connecting bridge 140 along the rotor core 100 is too small, the generated magnetic flux is insufficient, which will easily lead to the magnetic performance of the motor not meeting the standards.

[0091] Therefore, by setting the thickness H2 of the connecting bridge 140 along the axial direction of the rotor core 100 to satisfy 0.5 mm ≤ H2 ≤ 3 mm, it is possible to avoid waste of magnetic flux and material of the connecting bridge 140 while ensuring sufficient magnetic flux of the connecting bridge 140 .

[0092] In some embodiments, Figure 4 and Figure 5As shown, the outer circumference of the support portion 110 includes a first wall segment 132 , a second wall segment 133 and a third wall segment 134 , and the first wall segment 132 , the second wall segment 133 and the third wall segment 134 are all arcs with the center of curvature facing the inside of the rotor core 100 .

[0093] Among them, Figure 4 and Figure 5 As shown, the center of the second wall segment 133 can be the same as the center of the support portion 110, the second wall segment 133 can be symmetrical with respect to the symmetry plane of the tooth portion 130, the first wall segment 132 and the third wall segment 134 are respectively located on both sides of the second wall segment 133 in the circumferential direction of the rotor core 100, that is, the first wall segment 132 and the third wall segment 134 are also symmetrical with respect to the symmetry plane of the tooth portion 130, and the center of the first wall segment 132 and the third wall segment 134 is different from the center of the second wall segment 133.

[0094] By configuring the outer circumferential surface of the support portion 110 to include the first wall segment 132 , the second wall segment 133 , and the third wall segment 134 , the harmonic content can be reduced and the torque pulsation can be lowered.

[0095] In some embodiments, Figure 4 and Figure 5 As shown, it satisfies: R1 is the radius of the second wall segment 133 , and R2 is the radius of the first wall segment 132 and the third wall segment 134 .

[0096] The radii of the first wall segment 132 and the third wall segment 134 are equal, and the centers of the first wall segment 132 and the third wall segment 134 are symmetrically arranged with respect to the symmetry plane of the tooth portion 130 .

[0097] By setting the radius of the first wall segment 132, the second wall segment 133 and the third wall segment 134 to satisfy The influence of the large difference between R1 and R2 on the magnetic field can be avoided, so as to further reduce the harmonic content and further reduce the torque pulsation.

[0098] In some embodiments, Figure 4 and Figure 5 As shown, it satisfies: C1 is the circumferential length of the outer circumference of the support portion 110 around the rotor core 100, S1 is the distance from the center of the first wall segment 132 and the third wall segment 134 to the symmetry plane of the tooth portion 130, S2 is the distance from the center of the first wall segment 132 and the third wall segment 134 to the first center plane, the axis of the rotor core 100 is located on the first center plane, and the first center plane is perpendicular to the symmetry plane of the tooth portion 130.

[0099] By limiting the range of the above two ratios and the range of the ratio of R1 to R2, the center position range of the first wall segment 132 and the third wall segment 134 can be limited to ensure that the center of the first wall segment 132 and the third wall segment 134 are within a suitable position range, and avoid the center position of the first wall segment 132 and the third wall segment 134 being too remote relative to the center position of the second wall segment 133, so as to ensure the effect of the first wall segment 132, the second wall segment 133 and the third wall segment 134 on reducing harmonic content and torque pulsation.

[0100] like Fig.12 and Fig.13 As shown, Fig.12 is a back electromotive force data diagram of a comparative example; Fig.13 is a back electromotive force data diagram of a motor having a rotor core 100 provided in an embodiment of the present application; it can be seen that the motor having the rotor core 100 provided in this embodiment is compared with the motor provided in the comparative embodiment, Fig.13 The ratio of m2 and m3 to m1 Fig.12 The ratios of m2 and m3 to m1 are respectively small, and the back electromotive force value of the motor having the rotor core 100 provided in this embodiment is smaller than the back electromotive force value of the motor provided in the comparative embodiment, which can help reduce harmonic vibration and harmonic loss, and at the same time help reduce the torque pulsation of the motor.

[0101] In some embodiments, Figure 6 and Figure 7 As shown, the outer circumferential surface of the support portion 110 includes a first straight segment 135, a second arc segment 136, a third arc segment 137, a fourth arc segment 138 and a fifth straight segment 139, and the second arc segment 136, the third arc segment 137 and the fourth arc segment 138 are all arcs with the center of curvature facing the inside of the rotor core 100.

[0102] Among them, Figure 6 and Figure 7 As shown, the first straight line segment 135 and the fifth straight line segment 139 are both L4, the center of the third arc segment 137 can be the same as the center of the support portion 110, and the third arc segment 137 is symmetrical with respect to the symmetry plane of the tooth portion 130, the second arc segment 136 and the fourth arc segment 138 are also symmetrical with respect to the symmetry plane of the tooth portion 130, and the centers of the second arc segment 136 and the fourth arc segment 138 are different from the center of the third arc segment 137, and the first straight line segment 135 and the fifth straight line segment 139 are also symmetrical with respect to the symmetry plane of the tooth portion 130.

[0103] By configuring the outer circumferential surface of the support portion 110 to include a first straight segment 135 , a second arc segment 136 , a third arc segment 137 , a fourth arc segment 138 and a fifth straight segment 139 , the harmonic content can be reduced and the torque pulsation can be lowered.

[0104] In some embodiments, Figure 6 and Figure 7 As shown, it satisfies:

[0105] 0.5mm≤H1≤1.5mm, wherein r1 is the radius of the third arc segment 137, H1 is the radial distance between the vertices of the first straight segment 135 and the fifth straight segment 139 and the third arc segment 137, R3 is the radius of the second arc segment 136 and the fourth arc segment 138, C2 is the circumferential length of the outer circumference of the support portion 110 around the rotor core 100, S3 is the distance from the center of the second arc segment 136 and the fourth arc segment 138 to the symmetry plane of the tooth portion 130, S4 is the distance from the center of the second arc segment 136 and the fourth arc segment 138 to the first center plane, the axis of the rotor core 100 is located on the first center plane, and the first center plane is perpendicular to the symmetry plane of the tooth portion 130.

[0106] Among them, the first straight line segment 135 and the fifth straight line segment 139 are respectively located at the tooth boots on both sides of the circumferential direction of the tooth portion 130 of the rotor core 100, that is, the first straight line segment 135 and the fifth straight line segment 139 are respectively the radial outer side surfaces of the two tooth boots on the same tooth portion 130, and the first straight line segment 135 and the fifth straight line segment 139 are both parallel to the radial inner side surfaces of the tooth boots.

[0107] By limiting the ranges of the above three ratios and the range of H1, and setting the first straight line segment 135 and the fifth straight line segment 139 to be parallel to the radial inner side surface of the tooth shoe, the center position range of the second arc segment 136 and the fourth arc segment 138 can be limited, and the position relationship of the first straight line segment 135 and the fifth straight line segment 139 relative to the second arc segment 136 and the fourth arc segment 138 can be limited, respectively, to ensure that the center of the second arc segment 136 and the fourth arc segment 138 are within a suitable position range, to avoid the center position of the second arc segment 136 and the fourth arc segment 138 being too remote relative to the center position of the third arc segment 137, and to avoid the first straight line segment 135 and the fifth straight line segment 139 being too inclined relative to the second arc segment 136 and the fourth arc segment 138, so as to ensure the effect of the first straight line segment 135, the second arc segment 136, the third arc segment 137, the fourth arc segment 138 and the fifth straight line segment 139 on reducing harmonic content and torque pulsation.

[0108] like Fig.12 and Fig.14 As shown, Fig.12 is a back electromotive force data diagram of a comparative example; Fig.14 is a back electromotive force data diagram of a motor having a rotor core 100 provided in an embodiment of the present application; it can be seen that the motor having the rotor core 100 provided in this embodiment is compared with the motor provided in the comparative embodiment, Fig.14The ratio of m2 and m3 to m1 Fig.12 The ratios of m2 and m3 to m1 are respectively small, and the back electromotive force value of the motor having the rotor core 100 provided in this embodiment is smaller than the back electromotive force value of the motor provided in the comparative embodiment, which can help reduce harmonic vibration and harmonic loss, and at the same time help reduce the torque pulsation of the motor.

[0109] In some embodiments, the axial height of the rotor core 100 is H4, which satisfies: 9 mm ≤ H4 ≤ 21 mm.

[0110] During actual use, when the rotor core 100 is installed in the motor, it needs to be installed in coordination with other components in the motor, that is, the size of the rotor core 100 will affect the size of some components in the motor that cooperate with the rotor core 100. For example, the larger the size of the rotor core 100, the larger the size of some components; the smaller the size of the rotor core 100, the smaller the size of some components.

[0111] By limiting the axial height H4 of the rotor core 100 to satisfy: 9mm≤H4≤21mm, the thickness of the rotor core 100 can be reduced, thereby reducing the thickness of some components that cooperate with the rotor core 100, and further helping to reduce the overall thickness of the motor, so as to help the motor adapt to narrower or shorter usage scenarios, and at the same time avoid the rotor core 100 being too thin, resulting in low strength and easy damage.

[0112] The embodiment of the present application further provides a rotor assembly of a motor, the rotor assembly of the motor comprising: a rotor core 100 of the motor as in any of the above embodiments, a permanent magnet and a motor shaft 150.

[0113] The support portion 110 of the rotor core 100 has a center hole 112, the motor shaft 150 is installed in the center hole 112, the permanent magnet is installed on the rotor core 100, and one end of the motor shaft 150 is arranged through the center hole 112 of the support portion 110, serving as the output end of the rotor assembly. The motor shaft 150 is used for power coupling connection with the input end of subsequent equipment.

[0114] According to the rotor assembly of the motor provided in the embodiment of the present application, by adopting the rotor core 100 of any of the above embodiments, the harmonic content of the motor can be reduced, the torque pulsation of the motor can be reduced, and thus the performance of the motor can be improved.

[0115] The present application also provides a motor, such as Figure 8-Figure 11 As shown, the motor includes a rotor assembly, an end cover 300 and a stator assembly 200 of the motor as in any of the above embodiments.

[0116] Among them, Fig. 9As shown, the stator assembly 200 includes a stator core 210 and a winding arranged on the stator core 210. The stator core 210 can be a circular ring structure. The stator core 210 is provided with a plurality of winding grooves 211 spaced apart along the circumferential direction. The cross-section of the winding grooves 211 can be rectangular, circular or other shaped structures. The inner wall surface of the stator core 210 is provided with openings at positions corresponding to the winding grooves 211.

[0117] like Fig. 9 As shown, the number of the winding grooves 211 can be 18, or other numbers of the winding grooves 211 can be set.

[0118] like Figure 8 and Fig.10 As shown, the stator assembly 200 has a receiving cavity opened at a first end face, and the lead 230 of the stator assembly 200 is led out from a second end face opposite to the first end face, the first end face of the stator assembly 200 can be the upper end face of the stator assembly 200, and the second end face can be the lower end face of the stator assembly 200, that is, the upper end of the stator assembly 200 is provided with a receiving cavity recessed downward relative to the upper end face, and the lead 230 of the stator assembly 200 is led out from the lower end face of the stator assembly 200.

[0119] like Figure 8 As shown, Figure 8 and Fig.10 As shown, the end cover 300 is installed on the first end surface to close the accommodating cavity, at least a portion of the rotor assembly is installed in the accommodating cavity, and the motor shaft 150 of the rotor assembly passes through the end cover 300, the rotor core 100 and the permanent magnet of the rotor assembly are installed in the accommodating cavity of the stator assembly 200, the end cover 300 is installed on the upper ends of the rotor core 100 and the permanent magnet, and cooperates with the stator assembly 200, one end of the motor shaft 150 of the rotor assembly passes through the center hole 112 of the rotor core 100 and the shaft hole on the end cover 300 in sequence, and the outer periphery of the motor shaft 150 extending out of the end cover 300 is provided with a retaining pin 151.

[0120] According to the motor of the embodiment of the present application, by leading out the lead wire 230 of the stator assembly 200 from the lower end surface of the stator assembly 200, the motor can be installed in a designated installation position when the radial space is small, thereby expanding the application range of the motor.

[0121] In some embodiments, Figure 8 , Fig.10 and Fig.11 As shown, the end cover 300 is interference-fitted with the inner peripheral wall 220 of the stator assembly 200 .

[0122] Among them, Figure 8 , Fig.10 and Fig.11As shown, the end cover 300 as a whole can be presented as a stepped shaft structure, the first section 311 of the end cover 300 extends into the accommodating cavity, and the outer peripheral surface of the first section 311 of the end cover 300 is interference fit with the inner peripheral wall 220 of the stator assembly 200, the upper end diameter of the accommodating cavity is larger than the lower end diameter of the accommodating cavity, that is, a step surface is formed between the upper end and the lower end of the accommodating cavity, the lower end surface of the second section 312 of the end cover 300 is supported on the step surface of the accommodating cavity, and the upper end surface of the second section 312 of the end cover 300 can be flush with the first end surface of the stator assembly 200.

[0123] By interference fitting the end cover 300 with the inner circumferential wall 220 of the stator assembly 200 , the connection stability between the end cover 300 and the stator assembly 200 can be improved, and the number of parts connected between the end cover 300 and the stator assembly 200 can be reduced, thereby reducing costs.

[0124] In some embodiments, Fig.10 As shown, a notch 221 is provided at one end of the inner circumferential wall 220 of the stator assembly 200 facing the first end surface.

[0125] Among them, Fig.10 As shown, a plurality of notches 221 are circumferentially spaced apart at one end of the inner circumferential wall 220 of the stator assembly 200 facing the first end surface. The notches 221 may be rectangular, V-shaped or in other shapes.

[0126] In actual implementation, the first section 311 of the end cover 300 is installed in the accommodating cavity of the stator assembly 200 , and the portion of the inner circumferential wall 220 of the stator assembly 200 without the notch 221 is interference fit with the outer circumferential surface of the first section 311 of the end cover 300 .

[0127] By setting a notch 221 at one end of the inner circumferential wall 220 of the stator assembly 200 facing the first end surface, deformation space can be provided for the inner circumferential wall 220 of the stator assembly 200 on both sides of the notch 221, thereby increasing the interference space and reducing the fitting area to facilitate pressing the end cover 300.

[0128] In some embodiments, Fig.11 As shown, the end cover 300 includes a bearing chamber 320 and a cover body 310 .

[0129] Among them, Figure 8 As shown, a bearing 400 is provided on the outer sleeve of the motor shaft 150, and the bearing 400 is installed in the bearing chamber 320. A gasket 500 is provided between the upper end surface of the bearing 400 and the inner wall surface of the bearing chamber 320. The cover body 310 is covered on the outer peripheral surface of the bearing chamber 320, and a shaft hole is provided on the end surface of the cover body 310 corresponding to the bearing chamber 320.

[0130] like Fig.11As shown, the bearing housing 320 may be made of metal material, including but not limited to cast iron and cast aluminum.

[0131] A bearing groove is provided at the bottom of the accommodating cavity, and two bearings 400 are respectively installed in the bearing groove and the bearing chamber 320, and the rotor assembly is installed between the two bearings 400. One end of the motor shaft 150 is located in the bearing groove of the accommodating cavity, and the bearing 400 installed in the bearing groove is installed on the outer periphery of the motor shaft 150. The other end of the motor shaft 150 passes through the center hole 112 of the rotor assembly, the bearing 400 installed in the bearing chamber 320, and the cover body 310 in sequence.

[0132] By configuring the end cover 300 to include the bearing chamber 320 and the cover body 310 , the bearing chamber 320 can be used to provide an installation space for the bearing 400 , and the cover body 310 can be used to provide a certain strength for the bearing chamber 320 .

[0133] In some embodiments, the cover 310 is injection molded on the outer circumference of the bearing chamber 320 .

[0134] The cover body 310 may be made of a BMC (Bulk Molding Compound) material, that is, the outer peripheral surface of the bearing chamber 320 is made into the cover body 310 by a BMC injection molding process.

[0135] By setting the cover body 310 to be injection molded on the outer peripheral surface of the bearing chamber 320 using BMC, the molding cycle of the cover body 310 can be shortened, which is convenient for mass production, and the mold cost is low, which can reduce the production cost to a certain extent.

[0136] In some embodiments, Fig.11 As shown, the bearing chamber 320 includes a tube body 321, a first end of the tube body 321 is provided with a first flange 322 folded radially outward, the first flange 322 is embedded in the cover body 310, and a second end of the tube body 321 is provided with a second flange 323 folded radially inward, the surface of the second flange 323 away from the first flange 322 and the surface of the second flange 323 away from the tube body 321 are embedded in the cover body 310.

[0137] like Fig.11 As shown, the length of the first flange 322 may be smaller than the length of the second flange 323 . When the bearing 400 is installed in the bearing chamber 320 , the inner side surface of the second flange 323 abuts against the gasket 500 , providing a certain supporting force for the bearing 400 .

[0138] By providing the first flange 322 and the second flange 323 on the tube body 321 and embedding the first flange 322 and the second flange 323 into the cover body 310 , the connection stability and connection strength between the bearing chamber 320 and the cover body 310 can be improved, thereby extending the service life of the bearing chamber 320 .

[0139] In some embodiments, the stator assembly 200 includes an insulating frame wrapped around the stator core 210 , and the winding is wound outside the insulating frame.

[0140] The insulating frame is formed on the outside of the stator core 210 by injection molding, and the winding is wound on the outside of the insulating frame. After the winding is completed, the stator assembly 200 is formed by BMC injection molding.

[0141] By providing an insulating frame outside the stator core 210, short circuit between the winding and the stator core 210 or other components can be avoided. By forming the stator assembly 200 by BMC injection molding, the molding cycle of the stator assembly 200 can be shortened, which is convenient for mass production. The mold cost is low, which can reduce the production cost to a certain extent.

[0142] In some embodiments, the following conditions are met:

[0143] 0.65≤α≤0.75, wherein α=diameter of the accommodating cavity / outer diameter of the stator assembly 200 .

[0144] By limiting α to between 0.65 and 0.75, the area of ​​the winding slot 211 can be prevented from being too small while ensuring a large air gap diameter, thereby improving the motor output torque while preventing the winding slot 211 from being too small and affecting the magnetic field.

[0145] An embodiment of the present application further provides an electrical appliance, comprising a power supply and a motor as in any of the above embodiments, wherein an input end of the motor is electrically connected to the power supply.

[0146] Electrical appliances may include but are not limited to microwave ovens, induction cookers, electric ovens, dishwashers, etc.

[0147] According to the electrical appliance of the embodiments of the present application, by adopting the motor of any of the above embodiments, the motor can be installed in a designated installation position when the radial space is small, thereby reducing the overall volume and occupied space of the electrical appliance.

[0148] The terms "first", "second", etc. in the specification and claims of the present application are used to distinguish similar objects, and are not used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable under appropriate circumstances, so that the embodiments of the present application can be implemented in an order other than those illustrated or described here, and the objects distinguished by "first", "second", etc. are generally of one type, and the number of objects is not limited. For example, the first object can be one or more. In addition, "and / or" in the specification and claims represents at least one of the connected objects, and the character " / " generally indicates that the objects associated with each other are in an "or" relationship.

[0149] In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0150] In the description of this application, "first feature" or "second feature" may include one or more of the features.

[0151] In the description of the present application, “plurality” means two or more.

[0152] In the description of the present application, a first feature being “on” or “under” a second feature may include that the first and second features are directly in contact with each other, or may include that the first and second features are not in direct contact with each other but are in contact with each other via another feature therebetween.

[0153] In the description of the present application, “above”, “over” and “above” a first feature to a second feature includes the first feature being directly above and obliquely above the second feature, or simply means that the first feature is horizontally higher than the second feature.

[0154] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0155] Although the embodiments of the present application have been shown and described, those skilled in the art will appreciate that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present application, and that the scope of the present application is defined by the claims and their equivalents.

Claims

1. A rotor core of a motor, characterized in that: include: Supporting part; A plurality of tooth portions are spaced apart and distributed around the circumference of the support portion, rotor slots for mounting permanent magnets are formed between adjacent tooth portions, the tooth portions extend radially along the rotor core, and the radial outer peripheral surface of the tooth portions along the rotor core includes a plurality of wall segments connected sequentially around the circumference of the rotor core.

2. The rotor core of the motor according to claim 1, characterized in that: The support portion is connected to the tooth portion via a connecting portion, and one end of the connecting portion close to the tooth portion is provided with a positioning protrusion protruding toward the circumferential direction of the rotor core, and the positioning protrusion defines the radial inner end of the rotor slot.

3. The rotor core of the motor according to claim 1, characterized in that: The outer peripheral wall of the support portion is provided with a reinforcing rib, and the reinforcing rib protrudes toward the rotor slot.

4. The rotor core of the motor according to claim 3, characterized in that: The distance between the reinforcing rib and the radial inner end of the rotor slot is A, satisfying: A≥0.8mm.

5. The rotor core of the motor according to claim 1, characterized in that: The support portion is connected to the tooth portion via a connecting portion, and a width of the connecting portion along the circumferential direction of the rotor core is H3, satisfying: 0.6 mm ≤ H3 ≤ 0.9 mm.

6. The rotor core of the motor according to claim 1, characterized in that: Also includes: A connecting bridge, wherein the radial outer ends of two adjacent teeth are connected via the connecting bridge.

7. The rotor core of the motor according to claim 6, characterized in that: The thickness of the connecting bridge along the axial direction of the rotor core is H2, which satisfies: 0.5mm≤H2≤3mm.

8. The rotor core of the motor according to any one of claims 1 to 7, characterized in that: The outer circumferential surface of the support portion includes a first wall segment, a second wall segment and a third wall segment, and the first wall segment, the second wall segment and the third wall segment are all arcs with the center of curvature facing the inside of the rotor core.

9. The rotor core of the motor according to claim 8, characterized in that: satisfy: Wherein R1 is the radius of the second wall segment, and R2 is the radius of the first wall segment and the third wall segment.

10. The rotor core of the motor according to claim 9, characterized in that: satisfy: C1 is the circumferential length of the outer circumference of the tooth portion around the rotor core, S1 is the distance from the center of the first wall segment and the third wall segment to the symmetry plane of the tooth portion, S2 is the distance from the center of the first wall segment and the third wall segment to the first center plane, the axis of the rotor core is located on the first center plane, and the first center plane is perpendicular to the symmetry plane of the tooth portion.

11. The rotor core of the motor according to any one of claims 1 to 7, characterized in that: The outer circumferential surface of the support portion includes a first straight segment, a second arc segment, a third arc segment, a fourth arc segment and a fifth straight segment, and the second arc segment, the third arc segment and the fourth arc segment are all arcs with the center of curvature facing the inside of the rotor core.

12. The rotor core of the motor according to claim 11, characterized in that: satisfy: 0.5mm≤H1≤1.5mm, wherein r1 is the radius of the third arc segment, R3 is the radius of the second arc segment and the fourth arc segment, H1 is the radial distance between the first straight line segment and the fifth straight line segment and the vertex of the third arc segment, C2 is the circumferential length of the outer circumferential surface of the support portion around the rotor core, S3 is the distance from the center of the second arc segment and the fourth arc segment to the symmetry plane of the tooth portion, S4 is the distance from the center of the second arc segment and the fourth arc segment to the first center plane, the axis of the rotor core is located on the first center plane, and the first center plane is perpendicular to the symmetry plane of the tooth portion.

13. The rotor core of the motor according to any one of claims 1 to 7, characterized in that: The axial height of the rotor core is H4, which satisfies: 9mm≤H4≤21mm.

14. A rotor assembly of a motor, characterized in that: include: The rotor core of the motor according to any one of claims 1 to 13, wherein the support portion has a central hole; A permanent magnet, the permanent magnet being mounted on the rotor core; A motor shaft is mounted in the center hole.

15. A motor, characterized in that: include: The rotor assembly of the electric machine as claimed in claim 14; The stator assembly is installed outside the rotor assembly.

16. An electrical appliance, characterized in that: include: power supply; The motor according to claim 15, wherein an input terminal of the motor is electrically connected to the power supply.

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