Permanent magnet type brushless motor and washing machine

Abstract

The utility model relates to the technical field of washing machines, and particularly discloses a permanent magnet type brushless motor and a washing machine, the permanent magnet type brushless motor comprises a rotor core, a stator core and a plugging assembly, the stator core sleeves the outer side of the rotor core, the rotor core is provided with permanent magnets at intervals along the circumferential direction, and the stator core is provided with windings at intervals along the circumferential direction; the plugging assembly is connected with the winding so as to electrify the winding; the stator iron core is provided with a plurality of installation parts, each installation part protrudes out of the outer side wall of the stator iron core in the direction away from the rotor iron core, the outer side wall of the stator iron core comprises a linear part and an arc-shaped part, and the arc-shaped part is connected between the installation parts and the linear part. By adjusting the shape of the outer side wall of the stator iron core, the outer side wall of the stator iron core can adapt to the trend of the magnetic induction line, the magnetic induction line cannot be expanded to the mounting part so as to prevent components such as screws at the mounting part from interfering with the magnetic induction line, and meanwhile, compared with a traditional stator iron core structure, the stator iron core is less in material consumption, and the cost is reduced. And weight reduction is realized.

Description

Technical Field

[0001] The present application relates to the technical field of washing machines, and in particular to a permanent magnet brushless motor and a washing machine. Background Art

[0002] With the introduction of new energy consumption standards and the increasing requirements for lightweight machines, it is urgent to innovate washing machine motors. At present, the application of three-phase permanent magnet synchronous motors in washing machines has good advantages. In order to maintain their advantages in the fierce market, manufacturers need to continuously optimize the performance of three-phase permanent magnet synchronous motors.

[0003] In the production process, the stator punchings or rotor punchings are processed by stamping technology. Due to the large number, from an economic point of view, one of the research directions is to design a reasonable shape to save materials to the greatest extent. The biggest problem encountered at present is to design a motor with a structure and weight that meet the requirements without affecting the magnetic flux. However, due to the limitations of factors such as the magnetic flux area requirement, structural strength, and installation requirements, it is difficult to meet the requirements for the design of the stator structure. Summary of the invention

[0004] Based on this, it is necessary to provide a permanent magnet brushless motor and a washing machine to address the above problems.

[0005] According to a first aspect of an embodiment of the present application, a permanent magnet brushless motor is provided, comprising a rotor core, a stator core and a plug-in assembly, wherein the stator core is sleeved on the outer side of the rotor core, the rotor core is provided with at least one permanent magnet at intervals along the circumferential direction, the stator core is provided with at least one winding at intervals along the circumferential direction, and the plug-in assembly connects each of the windings to energize each of the windings;

[0006] The stator core comprises a main body and a plurality of mounting portions, each of the mounting portions protruding from an outer wall of the main body in a direction away from the rotor core, the outer wall of the main body comprising a straight portion and an arcuate portion, the arcuate portion being connected between the mounting portion and the straight portion, and a maximum distance of the arcuate portion from a center point of the rotor core in a radial direction being less than or equal to a minimum distance of a locking portion on the mounting portion from a center point of the rotor core.

[0007] In one of the embodiments, the winding generates magnetic induction lines distributed in the stator core after being energized, and the curvature of the arc-shaped portion is adapted to the trajectory of the outermost magnetic induction lines located in the stator core.

[0008] In one embodiment, the thickness of the arc portion is greater than the thickness of the straight portion, the thickness of the arc portion is the distance from the outer wall to the inner wall of the stator core at the arc portion, and the thickness of the straight portion is the distance from the outer wall to the inner wall of the stator core at the straight portion.

[0009] In one embodiment, the ratio of the thickness of the arc portion to the thickness of the straight portion is between 1.58 and 1.6.

[0010] In one embodiment, a plurality of winding grooves are formed on the inner wall of the stator core along the circumferential direction, and stator teeth are formed between two adjacent winding grooves. The winding is wound around the outer periphery of the stator teeth and accommodated in the winding grooves.

[0011] In one embodiment, the stator tooth includes a tooth portion and a pole shoe portion, one end of the tooth portion is connected to the inner wall of the stator core, the other end of the tooth portion is connected to the pole shoe portion, and the width of the pole shoe portion in the circumferential direction of the stator core is greater than the width of the tooth portion in the circumferential direction of the stator core.

[0012] In one embodiment, the stator teeth are T-shaped.

[0013] In one of the embodiments, the stator core includes a plurality of axially stacked stator punching sheets, and each of the stator punching sheets is stacked according to a preset horizontal rotation angle.

[0014] In one embodiment, each of the stator punching sheets has a riveted structure, and two adjacent stator punching sheets are connected by the riveted structure.

[0015] In one of the embodiments, the rotor core is provided with magnetic steel slots for accommodating the permanent magnets at intervals along the circumferential direction, and a magnetic isolation area is formed between each of the magnetic steel slots.

[0016] In one embodiment, the rotor core includes a plurality of first rotor punchings and second rotor punchings stacked in the axial direction, wherein the outermost edges of the magnetic steel slots in the first rotor punchings in the radial direction have magnetic isolation grooves, and the magnetic isolation grooves are communicated with the magnetic steel slots, and the outermost edges of the magnetic steel slots in the second rotor punchings in the radial direction have magnetic isolation bridges, and the magnetic isolation bridges connect the magnetic isolation areas on both sides of the magnetic steel slots.

[0017] In one of the embodiments, along the axial direction of the rotor core, the orthographic projection of the magnetic isolation bridge on the magnetic isolation groove falls into the magnetic isolation groove.

[0018] In one of the embodiments, along the radial direction of the rotor core, the outermost edge of the magnetic isolation bridge coincides with the outermost edge of the magnetic isolation groove.

[0019] In one of the embodiments, the thickness of the magnetic isolation bridge in the radial direction is between 0.4 mm and 0.6 mm.

[0020] In one of the embodiments, the ratio of the outer edge slot diameter of the magnetic steel slot to the outer edge slot diameter of the magnetic isolation slot is between 1.57 and 1.61.

[0021] In one embodiment, a plurality of the first rotor punchings are stacked between two adjacent second rotor punchings.

[0022] In one embodiment, the first rotor punching sheet and the second rotor punching sheet are stacked according to a preset horizontal rotation angle.

[0023] In one embodiment, the first rotor punching and the second rotor punching are both provided with a riveted structure, and adjacent first rotor punchings or adjacent first rotor punchings and second rotor punchings are connected by the riveted structure.

[0024] In one of the embodiments, a protrusion is provided at the radial innermost edge of the magnetic steel slot in the second rotor punching sheet, and the protrusion protrudes toward the inside of the magnetic steel slot. When the permanent magnet is inserted into the magnetic steel slot along the axial direction of the rotor core, the protrusion is bent by the permanent magnet so that the protrusion applies a radial abutment force to the permanent magnet.

[0025] In one of the embodiments, the permanent magnet brushless motor further includes a front end cover and a rear end cover, and the front end cover and the rear end cover are respectively connected to two sides of the stator core through the mounting portion.

[0026] In one embodiment, the front end cover and the rear end cover are made of aluminum alloy.

[0027] According to a second aspect of an embodiment of the present application, a washing machine is provided, comprising the above-mentioned permanent magnet brushless motor.

[0028] In the permanent magnet brushless motor and washing machine provided in the embodiments of the present application, each mounting portion of the stator core protrudes from the outer wall of the main body of the stator core in a direction away from the rotor core, and the outer wall of the main body of the stator core includes a straight portion and an arc portion, the arc portion is connected between the mounting portion and the straight portion, and the maximum distance of the arc portion from the center point of the rotor core is radially less than or equal to the minimum distance of the locking portion on the mounting portion from the center point of the rotor core, that is, by adjusting the shape of the outer wall of the stator core, the outer wall of the stator core can adapt to the direction of the magnetic induction lines, and the magnetic induction lines will not extend to the mounting portion to avoid interference with the magnetic induction lines by components such as screws at the mounting portion. At the same time, compared with the structure of the traditional stator core, the stator core in the present application uses less material, thereby achieving weight reduction. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 A schematic diagram of the structure of a permanent magnet brushless motor provided in one embodiment of the present application;

[0030] Figure 2 A cross-sectional view of a permanent magnet brushless motor provided in one embodiment of the present application;

[0031] Figure 3 A schematic structural diagram of a stator core in a permanent magnet brushless motor provided in an embodiment of the present application;

[0032] Figure 4 It is the magnetic induction line distribution diagram corresponding to the permanent magnet brushless motor in the traditional technology;

[0033] Figure 5 A distribution diagram of magnetic induction lines corresponding to a permanent magnet brushless motor provided in one embodiment of the present application;

[0034] Figure 6 A three-dimensional structural diagram of a stator core in a permanent magnet brushless motor provided in an embodiment of the present application;

[0035] Figure 7 A schematic diagram of the structure of a riveted structure in a permanent magnet brushless motor provided in an embodiment of the present application;

[0036] Figure 8 A schematic diagram of the structure of a riveted structure in a permanent magnet brushless motor provided in an embodiment of the present application;

[0037] Fig. 9 A schematic diagram of the three-dimensional structure of a rotor core in a permanent magnet brushless motor provided in an embodiment of the present application;

[0038] Fig.10 A schematic diagram of the structure of a first rotor punching sheet in a permanent magnet brushless motor provided in an embodiment of the present application;

[0039] Fig.11 A schematic diagram of the structure of a second rotor punching sheet in a permanent magnet brushless motor provided in an embodiment of the present application;

[0040] Fig.12 A schematic diagram of the three-dimensional structure of a rotor core in a permanent magnet brushless motor provided in one embodiment of the present application.

[0041] Description of reference numerals:

[0042] 100, rotor core; 110, magnetic steel slot; 120, magnetic isolation area; 130, first rotor punching sheet; 131, magnetic isolation slot; 140, second rotor punching sheet; 141, magnetic isolation bridge; 142, raised portion; 200, stator core; 211, mounting portion; 212, straight portion; 213, arc portion; 220, winding slot; 230, stator tooth; 231, tooth portion; 232, pole shoe portion; 240, stator punching sheet; 250, riveted structure; 251, protrusion; 252, slot body; 300, permanent magnet; 400, winding; 500, magnetic induction line; 600, front end cover; 700, rear end cover. DETAILED DESCRIPTION

[0043] In order to facilitate the understanding of the present application, the present application will be described more fully below with reference to the relevant drawings. The preferred embodiments of the present application are given in the drawings. However, the present application can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to understand the disclosure of the present application more thoroughly and comprehensively.

[0044] In this application, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0045] The terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of this application, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0046] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used herein in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0047] Reference Figure 1 , 2, 6 and 9, in one embodiment, a permanent magnet brushless motor is provided, including a rotor core 100, a stator core 200 and a plug-in assembly. The stator core 200 is sleeved outside the rotor core 100. The rotor core 100 is provided with a plurality of permanent magnets 300 at circumferential intervals. The stator core 200 is provided with a plurality of windings 400 at circumferential intervals. The plug-in assembly connects each winding 400 to energize each winding 400.

[0048] Among them, the plug-in assembly can be connected to an external control component. The external control component can provide three-phase alternating current. The three-phase alternating current is provided to the winding 400 through the plug-in assembly, thereby generating a stator rotating magnetic field. The rotor core 100 forms a rotor magnetic field by relying on the permanent magnets 300. The two magnetic fields are coupled to make the motor rotate, that is, the rotor core 100 rotates at a high speed relative to the stator core 200.

[0049] Referring to Figure 3 , the stator core 200 has a body portion and a plurality of mounting portions 211 connecting the body portion. Each mounting portion 211 protrudes from the outer side wall of the body portion of the stator core 200 in a direction away from the rotor core 100. The outer side wall of the body portion of the stator core 200 includes a straight portion 212 and an arc portion 213. The arc portion 213 is connected between the mounting portion 211 and the straight portion 212.

[0050] The mounting portion 211 of the stator core 200 is mainly used for the installation and fixation of the stator core 200. Specifically, the stator core 200 can be connected to the corresponding end cover through the mounting portion 211.

[0051] In the traditional technology, the contour of the stator core 200 is generally rectangular. Among them, the mounting portions 211 are located at the four top corners of the rectangular stator core 200. This design has the following disadvantages: large weight and high cost; at the same time, referring to Figure 4 , the magnetic induction lines 500 generated after the winding 400 is energized will extend to the mounting portion 211. Since locking portions such as screws are usually arranged at the mounting portion 211, it will interfere with the magnetic induction lines 500, and then cause the phenomenon that the magnetic induction lines 500 are unevenly distributed and interfere with other magnetic induction lines 500.

[0052] In this application, each mounting portion 211 protrudes from the outer side wall of the body portion of the stator core 200 in a direction away from the rotor core 100, that is, it is equivalent to chamfering the two sides of the mounting portion 211 in the traditional technology. Thereby, the weight of the stator core 200 is reduced and the cost is lowered. At the same time, referring to Figure 5, wherein the maximum distance between the arc portion 213 and the center point of the rotor core 100 is less than or equal to the minimum distance between the locking portion on the mounting portion 211 and the center point of the rotor core 100, thereby ensuring that the magnetic induction lines 500 generated after the winding 400 is energized will not extend to the mounting portion 211, thereby preventing the screws and other components at the mounting portion 211 from affecting the magnetic induction lines 500 and preventing the magnetic induction lines 500 from being uneven. At the same time, in the solution of the present application, the shape of the outer wall of the stator core 200 is set to a straight portion 212 and an arc portion 213, and the arc portion 213 is connected between the mounting portion 211 and the straight portion 212, thereby making the shape of the outer wall of the stator core 200 adapt to the direction of the magnetic induction lines 500, so as to maximize the amount of magnetic induction lines 500 entering. In the above solution, a straight line segment area may be provided between the mounting portion 211 and the straight line portion 212, for example, a straight line segment area is provided at the connection between the arc portion 213 and the mounting portion 211, and the arc segment can be used to more smoothly connect the rounded corners. No absolute limitation is made here.

[0053] In this embodiment, after the winding 400 is energized, the magnetic induction lines 500 distributed in the stator core 200 are generated, and the arc shape of the arc portion 213 is set to adapt to the trajectory of the outermost magnetic induction lines 500 located in the stator core 200, so as to further ensure that the magnetic induction lines 500 can pass through to the maximum extent.

[0054] In one embodiment, the stator core 200 may have four mounting portions 211, and the four mounting portions 211 are respectively distributed at four corners of the stator core 200. In other embodiments, the stator core 200 may also have two or three mounting portions 211, etc. The number of mounting portions 211 may be set according to actual needs, and no absolute limitation is made here.

[0055] Reference Figure 3 In this embodiment, the thickness of the arc portion 213 is greater than the thickness of the straight portion 212, wherein the thickness of the arc portion 213 is the distance D from the outer wall to the inner wall of the stator core 200 at the arc portion 213, and the thickness of the straight portion 212 is the distance E from the outer wall to the inner wall of the stator core 200 at the straight portion 212. After the mounting portion 211 is chamfered, the magnetic induction line 500 that can originally extend to the mounting portion 211 cannot pass through the arc portion 213, but because in this embodiment, the thickness of the arc portion 213 is set to be greater than the thickness of the straight portion 212, the magnetic induction parameter passing through the arc portion 213 still meets the requirements, effectively ensuring the magnetic flux and improving the motor performance.

[0056] In one embodiment, the ratio between the thickness of the arc portion 213 and the thickness of the straight portion 212 is between 1.58 and 1.6. Specifically, it can be 1.58, 1.59, 1.6, etc. The ratio between the thickness of the arc portion 213 and the thickness of the straight portion 212 is set between 1.58 and 1.6. In the above-mentioned setting, the magnetic induction lines 500 are denser at the straight portion 212 and relatively sparse at the arc portion 213. Therefore, a relatively thicker arc portion 213 is required to ensure the magnetic flux, thereby ensuring that the performance of the motor will not be reduced; in addition, the arc portion 213 obtained by the chamfering process can better reflect the advantages of weight reduction and reduced material loss in the structure of the stator core 200 having multiple stator punchings 240.

[0057] It can ensure the magnetic flux while ensuring that the motor performance will not be reduced.

[0058] In one embodiment, the inner wall of the stator core 200 is provided with a plurality of winding slots 220 along the circumferential direction, and a stator tooth 230 is formed between two adjacent winding slots 220 . The winding 400 is wound around the outer periphery of the stator tooth 230 and accommodated in the winding slots 220 .

[0059] The tooth width of each stator tooth 230 may be the same, and the tooth width refers to the width of the stator tooth 230 along the circumference of the stator core 200. The stator tooth 230 provides a winding position for the winding 400, and the winding 400 is wound around the outer periphery of the stator tooth 230 and received by the winding slots 220 on both sides of the stator tooth 230.

[0060] In this embodiment, the stator tooth 230 includes a tooth portion 231 and a pole shoe portion 232, one end of the tooth portion 231 is connected to the inner wall of the stator core 200, the other end of the tooth portion 231 is connected to the pole shoe portion 232, and the width of the pole shoe portion 232 in the circumferential direction of the stator core 200 is greater than the width of the tooth portion 231 in the circumferential direction of the stator core 200. Since one end of the tooth portion 231 is connected to the inner wall of the stator core 200 and the other end is connected to the pole shoe portion 232, and the width of the pole shoe portion 232 in the circumferential direction of the stator core 200 is greater than the width of the tooth portion 231 in the circumferential direction of the stator core 200, the winding 400 can be more reliably wound on the stator tooth 230 and is not easy to fall off the stator tooth 230. A certain distance is maintained between the pole shoe portions 232 of two adjacent stator teeth 230.

[0061] Furthermore, the stator tooth 230 is in a T-shape, the pole shoe portion 232 is the horizontal portion of the upper half of the T, and the tooth portion 231 is the vertical portion of the lower half of the T.

[0062] In one embodiment, referring to Figure 6The stator core 200 includes a plurality of stator punching sheets 240 stacked in the axial direction, and each of the stator punching sheets 240 is stacked at a preset horizontal rotation angle. That is, the stator core 200 may be formed by stacking a plurality of stator punching sheets 240, and during the stacking process, each of the stator punching sheets 240 may be stacked at a preset horizontal rotation angle. In this embodiment, the preset horizontal rotation angle may be set to 90°.

[0063] In the conventional technology, due to processing errors, the surface of the punching sheet often becomes uneven, especially the punching sheet processed by the production process of the assembly line, the errors of which are usually concentrated, for example, concentrated in one or more places. If the punching sheets are stacked at a fixed angle, the surface of the stator core 200 after forming may be lower on one side and higher on the other side. In view of this phenomenon, in this embodiment, each stator punching sheet 240 is stacked at a preset horizontal rotation angle, thereby avoiding the problem of inconsistent surface height of the stator core 200 after forming due to stacking the punching sheets at a fixed angle, thereby effectively improving the balance during the rotation of the motor and achieving the effect of high speed and low noise.

[0064] In one embodiment, referring to Figure 6-Figure 8 , each of the stator punching sheets 240 has a riveted structure 250, and two adjacent stator punching sheets 240 are connected by the riveted structure 250. Specifically, each stator punching sheet 240 may be provided with a riveted structure 250, and the riveted structure 250 may be a protrusion 251 and a groove 252 corresponding to the protrusion 251, that is, the protrusion 251 and the groove 252 are respectively distributed on both sides of the stator punching sheet 240. When two stator punching sheets 240 are superimposed on each other, the protrusion 251 of one stator punching sheet 240 is riveted into the groove 252 of the other stator punching sheet 240, and so on. Multiple stator punching sheets 240 can be superimposed together by the riveted structure 250 to form a stator core 200, thereby ensuring the compactness and stability of the structure of the stator core 200 after forming.

[0065] There may be multiple riveted structures 250 on the same stator punching sheet 240 , and they are evenly distributed around the axial direction.

[0066] In one embodiment, the rotor core 100 is provided with magnetic steel slots 110 for placing the permanent magnets 300 at intervals along the circumferential direction, and a magnetic isolation area 120 is formed between each of the magnetic steel slots 110. In practical applications, eight magnetic steel slots 110 may be provided on the rotor core 100, and the eight magnetic steel slots 110 are evenly distributed along the circumferential direction of the rotor core 100.

[0067] In one embodiment, referring to Fig. 9The rotor core 100 includes a plurality of first rotor punchings 130 and second rotor punchings 140 stacked in sequence along the axial direction. In this embodiment, the rotor core 100 may be formed by alternately stacking the first rotor punchings 130 and the second rotor punchings 140. Specifically, a plurality of the first rotor punchings 130 may be stacked between two adjacent second rotor punchings 140, that is, a plurality of the first rotor punchings 130 are stacked and then a second rotor punching 140 is stacked.

[0068] Reference Fig.10 and Fig.11 The outermost edge of the magnetic steel slot 110 in the first rotor punching 130 in the radial direction has a magnetic isolation groove 131, and the magnetic isolation groove 131 is connected to the magnetic steel slot 110. The outermost edge of the magnetic steel slot 110 in the radial direction in the second rotor punching 140 has a magnetic isolation bridge 141, and the magnetic isolation bridge 141 connects the magnetic isolation areas 120 on both sides of the magnetic steel slot 110. Among them, the magnetic isolation groove 131 is an open structure, which can minimize magnetic leakage, which is conducive to improving electromagnetic utilization, and can also reduce consumables and reduce costs.

[0069] Among them, along the axial direction of the rotor core 100, the orthographic projection of the magnetic isolation bridge 141 on the magnetic isolation slot 131 falls into the magnetic isolation slot 131. Along the radial direction of the rotor core 100, the outermost edge of the magnetic isolation bridge 141 coincides with the outermost edge of the magnetic isolation slot 131. In one of the embodiments, the thickness of the magnetic isolation bridge 141 in the radial direction is between 0.4 mm and 0.6 mm, specifically 0.4 mm, 0.5 mm, or 0.6 mm, etc., thereby effectively improving the magnetic flux rate while meeting the structural strength requirements.

[0070] In one embodiment, the ratio of the outer edge slot diameter of the magnetic steel slot 110 to the outer edge slot diameter of the magnetic isolation slot 131 is between 1.57 and 1.61, and can be specifically 1.57, 1.58, 1.59, 1.60, 1.61, etc.

[0071] In this embodiment, the first rotor punching 130 and the second rotor punching 140 are stacked at a preset horizontal rotation angle. Similar to the stacking method of the stator punching 240, the rotor punchings are also stacked at a preset horizontal rotation angle, which may refer to the stacking between the first rotor punching 130 and the first rotor punching 130, or the stacking between the first rotor punching 130 and the second rotor punching 140. The preset horizontal rotation angle may be set to 90°.

[0072] Stacking the first rotor punching sheet 130 and the second rotor punching sheet 140 at a preset horizontal rotation angle can avoid the problem of inconsistent surface height of the formed rotor core 100 due to stacking the rotor punching sheets at a fixed angle. Therefore, during the rotation of the motor, the balance can be effectively improved and the effect of high speed and low noise can be achieved.

[0073] Similar to the stator punching 240, the first rotor punching 130 and the second rotor punching 140 are both provided with a rivet structure 250, and adjacent first rotor punchings 130 or adjacent first rotor punchings 130 and second rotor punchings 140 are connected by the rivet structure 250. For the specific content of the rivet structure 250, please refer to the previous description, which will not be repeated here.

[0074] In one embodiment, referring to Fig.12 A protrusion 142 is provided at the radial innermost edge of the magnetic steel slot 110 in the second rotor punching sheet 140, and the protrusion 142 protrudes toward the inside of the magnetic steel slot 110. When the permanent magnet 300 is inserted into the magnetic steel slot 110 along the axial direction of the rotor core 100, the protrusion 142 is bent by the permanent magnet 300 so that the protrusion 142 applies a radial abutment force to the permanent magnet 300.

[0075] When the permanent magnet 300 is inserted into the magnetic steel slot 110 along the axial direction, its two side walls in the circumferential direction are gap-fitted with the magnetic steel slot 110. In the radial direction, the outer end of the permanent magnet 300 is limited, and the inner end of the permanent magnet 300 can bend the protrusion 142, thereby causing the protrusion 142 to deform, and then the protrusion 142 applies abutment force to the permanent magnet 300 radially outward, thereby ensuring that the positions of multiple permanent magnets 300 after installation remain consistent, and the thrust of the protrusion 142 will stably fix each permanent magnet 300 in the same position, effectively reducing the micro-deformation of the permanent magnet 300 in the magnetic steel slot 110, and also significantly improving the vibration and high-frequency noise of the motor.

[0076] In one embodiment, referring to Figure 1, the permanent magnet brushless motor also includes a front end cover 600 and a rear end cover 700, and the front end cover 600 and the rear end cover 700 are respectively connected to the two sides of the stator core 200 through the mounting portion 211. Among them, the front end cover 600 and the rear end cover 700 are made of aluminum alloy, which are smaller in size and lighter in weight than the existing end covers, thereby reducing the cost, and there is no need to change the assembly method, and the assembly cost will not be increased. First of all, it is worth noting that the selection of the above-mentioned materials can also conduct the heat on the stator core 200 in a contact-type connection manner to ensure the heat dissipation efficiency; secondly, it is worth noting that the above-mentioned installation method makes the side wall of the stator core 200 exposed and directly placed in the air, so that the heat generated can be dissipated to the air without hindrance, thereby further improving the heat dissipation efficiency.

[0077] In one embodiment, a washing machine is provided, comprising the permanent magnet brushless motor provided in the above embodiment. Specifically, the washing machine has an inner drum, and the permanent magnet brushless motor drives the inner drum to rotate via an output shaft.

[0078] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0079] The above-described embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be construed as limiting the scope of the patent. It should be noted that, for a person of ordinary skill in the art, several modifications and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the attached claims.

Claims

1. A permanent magnet brushless motor, characterized in that: The invention comprises a rotor core, a stator core and a plug-in assembly, wherein the stator core is sleeved on the outer side of the rotor core, the rotor core is provided with at least one permanent magnet at intervals along the circumferential direction, the stator core is provided with at least one winding at intervals along the circumferential direction, and the plug-in assembly connects each of the windings to energize each of the windings; The stator core comprises a main body and a plurality of mounting portions, each of the mounting portions protruding from an outer wall of the main body in a direction away from the rotor core, the outer wall of the main body comprising a straight portion and an arcuate portion, the arcuate portion being connected between the mounting portion and the straight portion, and a maximum distance of the arcuate portion from a center point of the rotor core in a radial direction being less than or equal to a minimum distance of a locking portion on the mounting portion from a center point of the rotor core.

2. The permanent magnet brushless motor according to claim 1, characterized in that: The winding generates magnetic induction lines distributed in the stator core after being energized, and the curvature of the arc-shaped portion is adapted to the trajectory of the outermost magnetic induction lines located in the stator core.

3. The permanent magnet brushless motor according to claim 1, characterized in that: The thickness of the arc portion is greater than that of the straight portion. The thickness of the arc portion is the distance from the outer wall to the inner wall of the stator core at the arc portion, and the thickness of the straight portion is the distance from the outer wall to the inner wall of the stator core at the straight portion.

4. The permanent magnet brushless motor according to claim 3, characterized in that: The ratio of the thickness of the arc portion to the thickness of the straight portion is between 1.58 and 1.

6.

5. The permanent magnet brushless motor according to claim 1, characterized in that: The inner wall of the stator core is provided with a plurality of winding grooves along the circumferential direction, and a stator tooth is formed between two adjacent winding grooves. The winding is wound around the outer periphery of the stator tooth and is accommodated in the winding grooves.

6. The permanent magnet brushless motor according to claim 5, characterized in that: The stator tooth includes a tooth portion and a pole shoe portion, one end of the tooth portion is connected to the inner wall of the stator core, the other end of the tooth portion is connected to the pole shoe portion, and the width of the pole shoe portion in the circumferential direction of the stator core is greater than the width of the tooth portion in the circumferential direction of the stator core.

7. The permanent magnet brushless motor according to claim 5, characterized in that: The stator teeth are T-shaped.

8. The permanent magnet brushless motor according to claim 1, characterized in that: The stator core includes a plurality of stator punching sheets stacked in the axial direction, and each of the stator punching sheets is stacked according to a preset horizontal rotation angle.

9. The permanent magnet brushless motor according to claim 8, characterized in that: Each of the stator punching sheets has a riveted structure, and two adjacent stator punching sheets are connected by the riveted structure.

10. The permanent magnet brushless motor according to claim 1, characterized in that: The rotor core is provided with magnetic steel slots for accommodating the permanent magnets at intervals along the circumferential direction, and a magnetic isolation area is formed between each of the magnetic steel slots.

11. The permanent magnet brushless motor according to claim 10, characterized in that: The rotor core includes a plurality of first rotor punchings and second rotor punchings stacked in the axial direction, wherein the outermost edges of the magnetic steel slots in the first rotor punchings in the radial direction have magnetic isolation grooves, and the magnetic isolation grooves are communicated with the magnetic steel slots, and the outermost edges of the magnetic steel slots in the second rotor punchings in the radial direction have magnetic isolation bridges, and the magnetic isolation bridges connect the magnetic isolation areas on both sides of the magnetic steel slots.

12. The permanent magnet brushless motor according to claim 11, characterized in that: Along the axial direction of the rotor core, the orthographic projection of the magnetic isolation bridge on the magnetic isolation groove falls into the magnetic isolation groove.

13. The permanent magnet brushless motor according to claim 11, characterized in that: Along the radial direction of the rotor core, the outermost edge of the magnetic isolation bridge coincides with the outermost edge of the magnetic isolation groove.

14. The permanent magnet brushless motor according to claim 11, characterized in that: The thickness of the magnetic isolation bridge in the radial direction is between 0.4 mm and 0.6 mm.

15. The permanent magnet brushless motor according to claim 11, characterized in that: The ratio of the outer edge slot diameter of the magnetic steel slot to the outer edge slot diameter of the magnetic isolation slot is between 1.57 and 1.

61.

16. The permanent magnet brushless motor according to claim 11, characterized in that: A plurality of the first rotor punchings are stacked between two adjacent second rotor punchings.

17. The permanent magnet brushless motor according to claim 11, characterized in that: The first rotor punching sheet and the second rotor punching sheet are stacked according to a preset horizontal rotation angle.

18. The permanent magnet brushless motor according to claim 11, characterized in that: The first rotor punchings and the second rotor punchings are both provided with riveted structures, and adjacent first rotor punchings or adjacent first rotor punchings and second rotor punchings are connected via the riveted structures.

19. The permanent magnet brushless motor according to claim 11, characterized in that: The innermost edge of the magnetic steel slot in the second rotor punching sheet in the radial direction is provided with a protrusion, and the protrusion protrudes toward the inside of the magnetic steel slot. When the permanent magnet is inserted into the magnetic steel slot along the axial direction of the rotor core, the protrusion is bent by the permanent magnet so that the protrusion applies a radial abutment force to the permanent magnet.

20. The permanent magnet brushless motor according to claim 1, characterized in that: The permanent magnet brushless motor further comprises a front end cover and a rear end cover, wherein the front end cover and the rear end cover are respectively connected to two sides of the stator core through the mounting portion.

21. The permanent magnet brushless motor according to claim 20, characterized in that: The front end cover and the rear end cover are made of aluminum alloy.

22. A washing machine, characterized in that: It comprises a permanent magnet brushless motor as described in any one of claims 1-21.

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