Motors and household appliances

Abstract

The present invention discloses a motor and household appliances, and relates to the technical field of motors, wherein the motor comprises a stator assembly, a rotor assembly and a magnetic field induction device, the rotor assembly comprises a rotor core, a rotor end ring and a magnetic field generating component, the rotor end ring is connected to one axial end of the rotor core, and the magnetic field generating component is arranged in a groove of the rotor end ring; the magnetic field induction device and the magnetic field generating component are arranged at intervals along the axial direction of the rotor core; the rotor end ring is also provided with a first protrusion and a second protrusion, and the first protrusion and the second protrusion are located at both ends of the groove. The present invention makes the magnetic flux of the magnetic field of the first protrusion and the magnetic field of the second protrusion entering the magnetic field induction device cancel each other, and reduces the interference of the magnetic field of the motor on the magnetic field generating component.

Description

Technical Field

[0001] The present invention relates to the technical field of motors, and in particular to a motor and a household appliance. Background Art

[0002] In the related art, an AC motor with PG (Pulse Generator) speed regulation is usually provided with a magnetic ring on the rotor, and a Hall sensor is arranged above the magnetic ring. The Hall sensor obtains the speed signal of the rotor by sensing the change of the magnetic field of the magnetic ring, and then feeds the signal back to the motor to realize speed regulation. The magnetic ring of the traditional PG motor is installed at the bearing position of the rotating shaft, occupying the axial space of the motor. Therefore, under the limitation of the installation size of the motor, the power density of the motor cannot be improved. However, the existing PG motor also has a design of installing the magnetic ring on the rotor core, which can save the axial space of the motor, but the magnetic field of the motor will affect the magnetic field distribution of the magnetic ring, thereby causing the speed signal of the rotor obtained by the Hall sensor to be distorted. Summary of the invention

[0003] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, the present invention provides a motor that can solve the problem of limited axial space of the motor and effectively reduce the interference of the magnetic field of the motor on the magnetic field generating component.

[0004] The present invention also provides a household appliance having the motor.

[0005] According to an embodiment of the first aspect of the present invention, the motor comprises: a stator assembly having an accommodating cavity; a rotor assembly rotatably disposed in the accommodating cavity, the rotor assembly comprising a rotor core, a rotor end ring and a magnetic field generating component, the rotor end ring being connected to one axial end of the rotor core, the end of the rotor end ring away from the rotor core being provided with a groove, the magnetic field generating component being arranged in the groove; a magnetic field sensing device, the magnetic field sensing device comprising a magnetic field sensing device and a circuit board connected to the magnetic field sensing device, the magnetic field sensing device and the magnetic field generating component being spaced apart along the axial direction of the rotor core; wherein the rotor end ring is further provided with a first protrusion and a second protrusion, the first protrusion being located on a side of the groove away from the center of the rotor core, and the second protrusion being located on a side of the groove toward the center of the rotor core.

[0006] The motor according to the embodiment of the present invention has at least the following beneficial effects:

[0007] By arranging the magnetic field generating component in the groove of the rotor end ring, and arranging the magnetic field sensing device in the axial direction of the rotor core at intervals from the magnetic field generating component, the occupation of the axial space of the motor by the magnetic field generating component is reduced, and under the condition of the motor shell size limitation, the axial space of the motor is saved, the output power of the motor is increased, and thus the load capacity of the motor is increased. The rotor end ring is provided with a first protrusion and a second protrusion located on both sides of the groove along the radial direction of the rotor core, and the magnetic flux generated by the magnetic field of the first protrusion and the magnetic flux generated by the magnetic field of the second protrusion are in opposite directions, so that the magnetic flux of the magnetic field of the first protrusion and the magnetic field of the second protrusion respectively entering the magnetic field sensing device cancel each other, effectively reducing the interference of the magnetic field of the motor on the magnetic field generating component, and ensuring the accuracy of the speed signal of the motor.

[0008] According to some embodiments of the present invention, the width of the surface of the first protrusion along the radial direction of the rotor core is d12, and the width of the surface of the second protrusion along the radial direction of the rotor core is d32, satisfying: |d12-d32|≤6mm.

[0009] According to some embodiments of the present invention, the plane where the surface of the first protrusion lies is perpendicular to the axial direction of the rotor core, and the surface of the first protrusion includes a first outer contour line and a first inner contour line that are spaced apart, and the first outer contour line and the first inner contour line enclose a closed annular plane.

[0010] According to some embodiments of the present invention, the plane where the surface of the second protrusion lies is perpendicular to the axial direction of the rotor core, and the surface of the second protrusion includes a second outer contour line and a second inner contour line that are spaced apart, and the second outer contour line and the second inner contour line together form a closed annular plane.

[0011] According to some embodiments of the present invention, along the axial direction of the rotor core, the distance between the magnetic field generating component and the magnetic field sensing device is d1; the surface of the magnetic field generating component includes a third outer contour line and a third inner contour line arranged at intervals, and along the radial direction of the rotor core, the distance between the midline of the third outer contour line and the third inner contour line and the geometric center of the magnetic field sensing device is d2, satisfying:

[0012]

[0013] According to some embodiments of the present invention, along the axial direction of the rotor core, the distance between the magnetic field generating component and the magnetic field sensing device is d1, which satisfies: <d1≤3mm。

[0014] According to some embodiments of the present invention, the surface of the magnetic field generating component includes a third outer contour line and a third inner contour line that are spaced apart, and along the radial direction of the rotor core, the distance between the midline of the third outer contour line and the third inner contour line and the geometric center of the magnetic field sensing device is d2; the width of the surface of the magnetic field generating component along the radial direction of the rotor core is d3, satisfying: 0≤d2≤1 / 4·d3.

[0015] According to some embodiments of the present invention, the surface of the magnetic field generating component includes a third outer contour line and a third inner contour line arranged at intervals, the third outer contour line and the third inner contour line are both circular, and the third outer contour line and the third inner contour line enclose each other to form a closed circular plane.

[0016] According to some embodiments of the present invention, the magnetic field sensing device is a Hall sensor.

[0017] According to some embodiments of the present invention, the rotor assembly further includes a conductive component, two rotor end rings are provided and respectively connected to two axial ends of the rotor core, and the conductive component is connected between the two rotor end rings.

[0018] According to some embodiments of the present invention, the rotor end ring and the conductive component are integrally manufactured.

[0019] According to some embodiments of the present invention, the stator assembly and the magnetic field sensing device are plastic-encapsulated.

[0020] According to some embodiments of the present invention, the motor further comprises an end cover positioned and mounted with the stator assembly, and the end cover and the magnetic field generating component are respectively located at two ends of the rotor assembly along the axial direction of the rotor core.

[0021] According to some embodiments of the present invention, a surface of the magnetic field generating component protrudes from a surface of the first protrusion and a surface of the second protrusion.

[0022] A household appliance according to an embodiment of the second aspect of the present invention comprises the motor described in the above embodiment.

[0023] The household appliance according to the embodiment of the present invention has at least the following beneficial effects:

[0024] The motor using the first embodiment of the present invention reduces the occupation of the axial space of the motor by the magnetic field generating component by arranging the magnetic field generating component in the groove of the rotor end ring, and arranging the magnetic field sensing device in the axial direction of the rotor core at intervals from the magnetic field generating component, thereby saving the axial space of the motor under the condition of the motor shell size limitation, improving the output power of the motor, and thus improving the load capacity of the motor. The rotor end ring is provided with a first protrusion and a second protrusion located on both sides of the groove along the radial direction of the rotor core, and the magnetic flux generated by the magnetic field of the first protrusion and the magnetic flux generated by the magnetic field of the second protrusion are in opposite directions, so that the magnetic flux of the magnetic field of the first protrusion and the magnetic field of the second protrusion respectively entering the magnetic field sensing device cancel each other, effectively reducing the interference of the magnetic field of the motor on the magnetic field generating component, and ensuring the accuracy of the speed signal of the motor.

[0025] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The present invention will be further described below with reference to the accompanying drawings and embodiments, wherein:

[0027] Figure 1 A schematic diagram of a partial structure of a motor according to an embodiment of the present invention;

[0028] Figure 2 for Figure 1 A partial cross-sectional view of

[0029] Figure 3 for Figure 2 The enlarged view of point A in the middle;

[0030] Figure 4 for Figure 1 Schematic diagram of the structure of the middle rotor assembly, in which the magnetic ring is removed;

[0031] Figure 5 for Figure 1 Schematic diagram of the structure of the middle magnetic ring;

[0032] Figure 6 for Figure 5 Schematic diagram of top view;

[0033] Figure 7 A coordinate diagram showing a change in frequency fluctuation of a magnetic field sensed by a Hall sensor of a motor according to an embodiment of the present invention;

[0034] Figure 8 A coordinate diagram showing a change in frequency fluctuation of a magnetic field sensed by a Hall sensor of a motor according to another embodiment of the present invention;

[0035] Fig. 9 A schematic diagram of the structure of a motor according to an embodiment of the present invention;

[0036] Fig.10 for Fig. 9 A partial cross-sectional schematic diagram of .

[0037] Figure Number:

[0038] Rotor assembly 100; shaft 110; rotor core 120; conductive component 130; first end ring 140; second end ring 150; groove 160; magnetic ring 170; upper surface 171; third outer contour line S111; third inner contour line S112; center line S113; first protrusion 180; first surface 181; first outer contour line A111; first inner contour line A112; second protrusion 190; second surface 191; second outer contour line A311; second inner contour line A312;

[0039] Magnetic field sensing device 200; Hall sensor 210; sensing surface 211; circuit board 220;

[0040] Plastic-sealed stator 300; inner side surface 310;

[0041] A first end cap 400;

[0042] The second end cover 500 . DETAILED DESCRIPTION

[0043] Embodiments of the present invention are described in detail below, examples of which 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 invention, and cannot be understood as limiting the present invention.

[0044] In the description of the present invention, it should be understood that descriptions involving orientation, such as orientation or positional relationship indicated as up, down, etc., are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to 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 invention.

[0045] In the description of the present invention, "a plurality" means more than two. If there is a description of "first" or "second", it is only used for the purpose of distinguishing technical features, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features or implicitly indicating the order of the indicated technical features.

[0046] In the description of the present invention, unless otherwise clearly defined, terms such as setting, installing, connecting, etc. should be understood in a broad sense, and technicians in the relevant technical field can reasonably determine the specific meanings of the above terms in the present invention based on the specific content of the technical solution.

[0047] Reference Figure 1 As shown, Figure 1 The figure is a partial structural diagram of a motor according to an embodiment of the present invention. The motor according to an embodiment of the present invention is a PG motor, that is, an AC motor with a pulse generator for speed regulation. PG motors are widely used in household appliances such as air conditioners. The speed regulation of the PG motor is achieved by setting a magnet on the rotor and setting a Hall element above the magnet. The Hall element senses the change in the magnetic field of the magnet and obtains the rotation speed signal of the rotor, thereby feeding back the rotation speed signal to the motor.

[0048] The motor of the embodiment of the present invention includes a stator assembly (not shown in the figure) and a rotor assembly 100. The stator assembly has a receiving cavity, and the rotor assembly 100 is rotatably arranged in the receiving cavity. The stator assembly includes a stator core, and the stator core includes stator teeth evenly distributed along the circumferential direction and a stator yoke connected to the stator teeth, and coils are wound on the stator teeth to form a winding. The rotor assembly 100 includes a rotating shaft 110 and a rotor core 120 mounted on the rotating shaft 110, and the rotating shaft 110 is located at the center of the rotor core 120. The stator core is arranged around the outer periphery of the rotor core 120, and the stator core and the rotor core 120 are coaxially arranged, and an air gap is formed between the stator core and the rotor core 120. Among them, the air gap is the gap between the stator core and the rotor core 120, and the size of the air gap is set according to the actual use requirements of the motor.

[0049] Continue to refer to Figure 1 As shown, the rotor assembly 100 further includes a conductive component 130, a first end ring 140 and a second end ring 150, and the first end ring 140 and the second end ring 150 are respectively arranged at two ends of the axial direction of the rotor core 120. The conductive component 130 is a plurality of conductive bars, and the plurality of conductive bars are arranged at intervals along the circumferential direction of the rotor core 120, and the two ends of the conductive bars are respectively connected to the first end ring 140 and the second end ring 150. As another embodiment, the conductive component 130 can be replaced by a permanent magnet, which is arranged in the rotor core 120 and between the first end ring 140 and the second end ring 150.

[0050] Reference Figure 2 As shown, Figure 2 The figure is a partial cross-sectional view of a motor according to an embodiment of the present invention. The motor further comprises a magnetic field sensing device 200, which comprises a Hall sensor 210 and a circuit board 220. The Hall sensor 210 is connected to the circuit board 220, and the circuit board 220 can be installed on the housing of the motor. It should be noted that the Hall sensor 210 can also be replaced by other magnetic field sensing devices, which is not specifically limited here.

[0051] Reference Figure 4 and Figure 5 As shown, Figure 4It is a schematic structural diagram of a rotor assembly 100 in a motor of the present invention, wherein the magnetic ring 170 is removed. Figure 5 This is a schematic diagram of the structure of a magnetic ring 170 in a motor according to an embodiment of the present invention. The rotor assembly 100 also includes a magnetic ring 170. It should be noted that the magnetic ring 170 can also be replaced by other magnetic field generating components, which are not specifically limited here. The first end ring 140 is located above the rotor core 120. The surface of the first end ring 140 is provided with a groove 160. The groove 160 is annular and is located on the surface of the end of the first end ring 140 away from the rotor core 120. The magnetic ring 170 is installed in the groove 160. It should be noted that the upper surface 171 of the magnetic ring 170 (i.e., the surface away from the groove 160) is an annular plane, but is not limited to a circular annular plane, such as an elliptical annular plane, a petal annular plane, etc.

[0052] Reference Figure 3 As shown, Figure 3 for Figure 2 Enlarged view of point A in the middle. The Hall sensor 210 is located above the magnetic ring 170 along the axial direction of the rotor core 120, that is, it is spaced apart from the magnetic ring 170 along the axial direction of the rotor core 120. The magnetic field direction of the magnetic ring 170 of this embodiment is an axial magnetic field, and the installation position of the Hall sensor 210 can facilitate accurate sensing of the change of the magnetic field of the magnetic ring 170, obtain the speed signal of the rotor, and then feed the signal back to the motor to achieve speed regulation. Moreover, the magnetic ring 170 is installed in the first end ring 140, which can reduce the axial space occupied by the traditional installation position of the magnetic ring 170 on the rotating shaft 110, save the axial space of the motor, and increase the length of the rotor core 120 under the condition of the motor shell size limit. According to the basic principle of motor design, while ensuring that the motor speed remains unchanged, increasing the length of the rotor core 120 can increase the output power of the motor, thereby increasing the load capacity of the motor. It is understandable that the first end ring 140 may also be disposed below the rotor core 120 , and the Hall sensor 210 is then located below the magnetic ring 170 along the axial direction of the rotor core 120 .

[0053] Continue to refer to Figure 3 As shown, the Hall sensor 210 is provided with a sensing surface 211 for detecting magnetic field changes. The sensing surface 211 faces the magnetic ring 170 and is perpendicular to the axial direction of the rotor core 120, so that the sensing surface 211 detects the magnetic field of the magnetic ring 170 along the axial direction of the rotor core 120. As the magnetic ring 170 rotates with the rotor core 120, the magnetic field of the magnetic ring 170 is perpendicular to the sensing surface 211. The magnetic field change signal of the magnetic ring 170 can be sensed by the sensing surface 211, and the signal is sent to the control circuit of the motor, and then the operating voltage supplied to the motor is adjusted by the conduction angle of the thyristor, thereby realizing automatic control of the speed. The Hall sensor 210 has the advantages of firm structure, small size, light weight, long life, and easy installation.

[0054] Continue to refer to Figure 3 and Figure 4 As shown, it can be understood that the first protrusion 180 and the second protrusion 190 are respectively formed at both ends of the groove 160 along the radial direction of the first end ring 140. The first protrusion 180 is located on the side of the groove 160 away from the rotating shaft 110, and the second protrusion 190 is located on the side of the groove 160 facing the rotating shaft 110. It should be noted that the surface of the first protrusion 180 and the surface of the second protrusion 190 are both annular planes, but are not limited to circular annular planes, such as elliptical annular planes, petal annular planes, etc.

[0055] Reference Figure 2 and Figure 3 As shown, the magnetic ring 170 is arranged in the first end ring 140, and the magnetic field of the motor coincides with the magnetic field direction of the first end ring 140, causing the magnetic field of the motor to affect the magnetic field of the magnetic ring 170, so that the magnetic field entering the Hall sensor 210 is a synthetic magnetic field. Moreover, when the number of poles of the motor is not equal to the number of poles of the magnetic ring 170, the Hall sensor 210 will introduce magnetic field harmonics, causing the frequency to fluctuate and the speed signal to be distorted. It is further explained that according to Maxwell's law, when there is current in the first end ring 140, there is a magnetic field around it. Therefore, when the first end ring 140 is provided with a first protrusion 180 and a second protrusion 190, the direction of the magnetic flux lines of the magnetic field of the first protrusion 180 entering the Hall sensor 210 is opposite to the direction of the magnetic flux lines of the magnetic field of the second protrusion 190 entering the Hall sensor 210, so the magnetic flux of the magnetic field of the first protrusion 180 and the magnetic field of the second protrusion 190 entering the Hall sensor 210 cancel each other out, thereby reducing the interference of the magnetic field of the first end ring 140 on the magnetic field of the magnetic ring 170, reducing the influence of the magnetic field harmonics of the motor on the magnetic field entering the Hall sensor 210, and reducing the magnetic field frequency fluctuation of the Hall sensor 210.

[0056] Continue to refer to Figure 3 As shown, in order to solve the above problem, the surface width d12 of the first protrusion 180 and the surface d32 of the second protrusion 190 are set to be substantially the same, for example, satisfying the following definition: |d12-d32|≤6mm. Among them, the surface width of the first protrusion 180 along the radial direction of the rotor core 120 is d12, and the surface width of the second protrusion 190 along the radial direction of the rotor core 120 is d32. When the magnetic flux lines generated by the magnetic field of the first protrusion 180 and the magnetic flux lines generated by the magnetic field of the second protrusion 190 are in opposite directions, the magnetic fluxes of the magnetic field of the first protrusion 180 and the magnetic field of the second protrusion 190 respectively entering the Hall sensor 210 cancel each other, reducing the interference of the magnetic field of the motor on the magnetic ring 170.

[0057] Reference Figure 7 As shown, Figure 7The frequency fluctuation of the magnetic field sensed by the Hall sensor 210 of the motor of an embodiment of the present invention and the change of the value of |d32-d12| are shown in the coordinate diagram. It can be understood that this embodiment optimizes the value of |d32-d12|, combined with a large number of optimization calculations and a large number of experiments, so that the surface width d12 of the first protrusion 180 and the surface d32 of the second protrusion 190 satisfy the range of |d12-d32|≤6mm, and the frequency fluctuation of the magnetic field sensed by the Hall sensor 210 is minimized. Therefore, the motor of this embodiment is limited by the above parameters, so that the surface width d12 of the first protrusion 180 and the surface d32 of the second protrusion 190 are basically equal, so that the magnetic flux on the surface of the first protrusion 180 is basically equal to the magnetic flux on the surface of the second protrusion 190. The motor of this embodiment makes the magnetic flux of the magnetic field of the first protrusion 180 entering the Hall sensor 210 equal to the magnetic flux of the magnetic field of the second protrusion 190 entering the Hall sensor 210, and the magnetic flux lines generated by the magnetic field of the first protrusion 180 and the magnetic flux lines generated by the magnetic field of the second protrusion 190 are in opposite directions, so that the magnetic fluxes of the magnetic field of the first protrusion 180 and the magnetic field of the second protrusion 190 entering the Hall sensor 210 respectively cancel each other, avoiding the magnetic field of the first protrusion 180 and the magnetic field of the second protrusion 190 interfering with the detection of the magnetic field of the magnetic ring 170 by the Hall sensor 210, thereby achieving the effect of avoiding the magnetic field of the motor interfering with the magnetic field of the magnetic ring 170, and further achieving the purpose of stabilizing the magnetic field frequency of the Hall sensor 210. The motor of this embodiment makes the signal fluctuation of the Hall sensor 210 at a relatively small level, ensuring the accuracy of the speed signal of the motor.

[0058] In addition, the motor of this embodiment changes the frequency of the magnetic ring 170 by limiting the shape of the magnetic ring 170, thereby causing the magnetic field of the motor to coincide with the magnetic field frequency of the magnetic ring 170, thereby making the frequency of the magnetic field entering the Hall sensor 210 a constant value, thereby limiting the frequency fluctuation of the magnetic field sensed by the Hall sensor 210, and further ensuring the accuracy of the motor's speed signal.

[0059] Reference Figure 4 As shown, it can be understood that the plane where the first surface 181 of the first protrusion 180 (i.e., the surface facing one end of the Hall sensor 210) is located is parallel to the plane where the sensing surface 211 of the Hall sensor 210 is located, thereby ensuring that the Hall sensor 210 can more accurately sense the magnetic field of the magnetic ring 170, and improving the detection accuracy of the Hall sensor 210. The first surface 181 and the sensing surface 211 are both perpendicular to the axial direction of the rotor core 120, reducing the frequency fluctuation of the magnetic field sensed by the Hall sensor 210 during the rotation of the rotor assembly 100, and further ensuring the accuracy of the speed signal of the motor.

[0060] It is understood that the first surface 181 includes a first outer contour line A111 and a first inner contour line A112 that are spaced apart. The first outer contour line A111 can be circular, elliptical, a closed wavy line, a closed tooth shape, etc. The first inner contour line A112 can be circular, elliptical, a closed wavy line, a closed tooth shape, etc.

[0061] The first surface 181 is an annular plane formed by the first outer contour line A111 and the first inner contour line A112. The first surface 181 can be designed according to the parameter requirements of the motor, so that the motor can meet the actual use requirements.

[0062] Reference Figure 4 As shown, it can be understood that the plane where the second surface 191 of the second protrusion 190 (i.e., the surface facing one end of the Hall sensor 210) is located is parallel to the plane where the sensing surface 211 of the Hall sensor 210 is located, thereby ensuring that the Hall sensor 210 can more accurately sense the magnetic field of the magnetic ring 170, and improving the detection accuracy of the Hall sensor 210. The second surface 191 and the sensing surface 211 are both perpendicular to the axial direction of the rotor core 120, reducing the frequency fluctuation of the magnetic field sensed by the Hall sensor 210 during the rotation of the rotor assembly 100, and further ensuring the accuracy of the speed signal of the motor.

[0063] It is understandable that the second surface 191 includes a second outer contour line A311 and a second inner contour line A312 that are arranged at intervals. The second outer contour line A311 can be circular, elliptical, a closed wavy line, a closed tooth shape, etc. The second inner contour line A312 can be circular, elliptical, a closed wavy line, a closed tooth shape, etc.

[0064] The second surface 191 is an annular plane formed by the second outer contour line A311 and the second inner contour line A312. The second surface 191 can be designed according to the parameter requirements of the motor, so that the motor can meet the actual use requirements.

[0065] It can be understood that according to the working principle of the Hall sensor 210, the Hall sensor 210 is triggered only when the magnetic flux entering the sensing surface 211 is large enough. The distance between the sensing surface 211 and the magnetic ring 170 is closely related to the frequency fluctuation of the magnetic ring 170. When the distance is larger, the magnetic flux density is weaker. When there is a certain interference in the magnetic field, the influence of harmonics is more obvious, further increasing the frequency fluctuation of the magnetic ring 170. Among them, the magnetic field of the magnetic ring 170 has the highest magnetic induction intensity at the upper surface 171 of the magnetic ring 170. At a position close to the upper surface 171, the magnetic flux lines of each magnetic pole of the magnetic ring 170 are perpendicular to the upper surface 171. The magnetic induction intensity gradually weakens as it is farther away from the upper surface 171. The magnetic flux lines will also diverge in different directions. The magnetic flux lines far away from the upper surface 171 are not all perpendicular to the upper surface 171.

[0066] Referring to Figure 3 as shown, it can be understood that, as another implementation manner, the upper surface 171 of the magnetic ring 170 protrudes from the first end ring 140. That is, along the axial direction of the rotor core 120, the distance between the upper surface 171 of the magnetic ring 170 and the sensing surface 211 of the Hall sensor 210 is less than the distance between the first surface 181 of the first protrusion 180 and the sensing surface 211, and is also less than the distance between the second surface 191 of the second protrusion 190 and the sensing surface 211. Therefore, the magnetic field intensity of the magnetic ring 170 sensed by the Hall sensor 210 is large, enabling the Hall sensor 210 to detect more accurately. Moreover, the magnetic fields of the first protrusion 180 and the second protrusion 190 sensed by the Hall sensor 210 are small, so that the influence of the magnetic fields of the first protrusion 180 and the second protrusion 190 on the magnetic field of the magnetic ring 170 can be reduced, and the magnetic field of the motor can be prevented from interfering with the magnetic field of the magnetic ring 170, further improving the detection accuracy of the Hall sensor 210. Of course, in actual production, the upper surface 171 of the magnetic ring 170 can also be flush with the first end ring 140.

[0067] See Figure 3 as shown, it can be understood that in the embodiment of the present invention, the distance d1 between the upper surface 171 of the magnetic ring 170 and the sensing surface 211 of the Hall sensor 210 is optimized so that d1 satisfies: 0 < d1 ≤ 3 mm, that is, the distance between the sensing surface 211 and the upper surface 171 is not greater than 3 mm. Therefore, when d1 satisfies the above range, the magnetic field of the magnetic ring 170 is generally distributed along the axial direction and perpendicular to the sensing surface 211, which is beneficial to reducing the influence of harmonics and reducing the frequency fluctuation of the magnetic field sensed by the Hall sensor 210, thereby improving the detection accuracy of the Hall sensor 210. When d1 is greater than 3 mm, the magnetic induction lines will diverge along the direction of the magnetic field, the sensitivity of the sensing surface 211 to the magnetic field not perpendicular to the sensing surface 211 will decrease, and the magnetic induction intensity will also decrease, and the influence of harmonics will be greater, increasing the frequency fluctuation of the magnetic ring 170.

[0068] Referring to Figure 6 as shown Figure 61 is a schematic top view of a magnetic ring 170 in a motor according to an embodiment of the present invention. It is understood that in the radial direction of the rotor core 120, the upper surface 171 of the magnetic ring 170 has a certain width. The upper surface 171 of the magnetic ring 170 includes a third outer contour line S111 and a third inner contour line S112 that are spaced apart, and the third outer contour line S111 and the third inner contour line S112 enclose a closed annular plane. The width of the third outer contour line S111 and the third inner contour line S112 along the radial direction of the rotor core 120 can be understood as the width direction of the upper surface 171, and the curve formed by the set of midpoints between the third outer contour line S111 and the third inner contour line S112 can be understood as the center line S113 of the upper surface 171, and the center line S113 of the upper surface 171 can also be understood as the center line of the upper surface 171 along the width direction. The radial distance between the center line S113 and the geometric center of the sensing surface 211 is d2, the width of the upper surface 171 is d3, and d2 and d3 satisfy the following definition: 0≤d2≤1 / 4·d3. By defining the above parameters, the positional relationship and structure between the sensing surface 211 and the magnetic ring 170 can be optimized, and the frequency fluctuation of the magnetic field sensed by the Hall sensor 210 can be kept at a lower level. It can be understood that when the center line S113 of the upper surface 171 deviates greatly from the geometric center of the sensing surface 211, the magnetic field entering the sensing surface 211 is asymmetric, the magnetic field waveform is distorted, and the frequency fluctuation is more serious.

[0069] Reference Figure 5 and Figure 6 As shown, it can be understood that the magnetic ring 170 is an arc-shaped structure. The third outer contour line S111 is circular, and the third inner contour line S112 is also circular. Therefore, the upper surface 171 of the magnetic ring 170 is a circular plane formed by the third outer contour line S111 and the third inner contour line S112. When the positions of the Hall sensor 210 and the magnetic ring 170 are relatively fixed, the center line S113 of the upper surface 171 and the geometric center of the sensing surface 211 can coincide or have a small deviation, which can keep the frequency fluctuation of the magnetic field sensed by the Hall sensor 210 at a low level. Moreover, when d1 is greater than 0 and less than or equal to 3 mm, the influence of frequency fluctuation can be further reduced, making the motor more practical and reliable.

[0070] Reference Figure 3 As shown, it can be understood that the width of the surface of the first protrusion 180 along the radial direction of the rotor core 120 is d12. Along the axial direction of the rotor core 120, the distance between the upper surface 171 of the magnetic ring 170 and the sensing surface 211 of the Hall sensor 210 is d1. Along the radial direction of the rotor core 120, the distance between the center line S113 of the upper surface 171 of the magnetic ring 170 and the geometric center of the Hall sensor 210 is d2. By optimizing the product of d1 and d2, the following definition is met:

[0071]

[0072] Reference Figure 8 As shown, Figure 8 This is a coordinate diagram of the frequency fluctuation of the magnetic field sensed by the Hall sensor 210 of the motor according to an embodiment of the present invention and the change of the value of d1·d2. It can be understood that by optimizing the product of the axial distance d1 between the upper surface 171 of the magnetic ring 170 and the sensing surface 211 of the Hall sensor 210 and the radial distance d2 between the center line S113 of the upper surface 171 of the magnetic ring 170 and the geometric center of the Hall sensor 210, so that d1·d2 is within the range of the above parameters, combined with a large number of optimization calculations and a large number of experiments, it is shown that the frequency fluctuation of the magnetic field sensed by the Hall sensor 210 is at a relatively low level.

[0073] The motor of the embodiment of the present invention can reduce the asymmetric component of the magnetic field of the motor entering the Hall sensor 210, and further reduce the frequency fluctuation of the magnetic field sensed by the Hall sensor 210, thereby achieving the purpose of stabilizing the frequency of the magnetic field sensed by the Hall sensor 210. The magnetic field of the motor has little interference with the magnetic field of the magnetic ring 170, and the influence of the magnetic field of the motor can be ignored. The pulse signal output by the Hall sensor 210 has a high accuracy, which is conducive to more accurate adjustment of the motor speed.

[0074] According to the basic principle of the Hall sensor 210, when the magnetic flux entering the Hall sensor 210 is greater than the threshold, the Hall sensor 210 is in the on state. Therefore, the distance between the magnetic ring 170 and the Hall sensor 210 is closely related to the frequency fluctuation of the magnetic field sensed by the Hall sensor 210. When the axial distance between the upper surface 171 of the magnetic ring 170 and the sensing surface 211 of the Hall sensor 210 is larger, that is, the value of d1 is larger, the magnetic flux density is weaker, and when there is a certain interference in the magnetic field of the magnetic ring 170, the influence of harmonics is more obvious, further making the frequency fluctuation of the magnetic field sensed by the Hall sensor 210 larger. In addition, when the radial distance deviation between the center line S113 of the upper surface 171 of the magnetic ring 170 and the geometric center of the Hall sensor 210 is large, that is, the value of d2 is large, the magnetic field sensed by the Hall sensor 210 is asymmetric, and the magnetic field waveform is distorted, which further makes the frequency fluctuation of the magnetic field sensed by the Hall sensor 210 larger.

[0075] Therefore, in an embodiment of the present invention, when the values ​​of d1 and d2 are controlled to be smaller, it is beneficial to reduce the interference of the magnetic field of the first protrusion 180 and the magnetic field of the second protrusion 190 on the magnetic field of the magnetic ring 170, thereby reducing the effect of the magnetic field of the motor interfering with the magnetic field of the magnetic ring 170, so that the signal fluctuation of the Hall sensor 210 is at a smaller level, thereby ensuring the accuracy of the motor's speed signal.

[0076] Reference Figure 4As shown, it can be understood that the first end ring 140, the second end ring 150 and the conductive component 130 are integrally manufactured and formed, so that the structure of the rotor assembly 100 is more stable, thereby improving the structural stability of the motor.

[0077] As one of the embodiments, the first end ring 140, the second end ring 150 and the conductive component 130 are all made of aluminum material. The conductive component 130 is a plurality of aluminum bars connected between the first end ring 140 and the second end ring 150. The first end ring 140, the second end ring 150 and the plurality of aluminum bars can be formed by integral casting, thereby forming a stable connection structure with the rotor core 120, further improving the stability of the rotor assembly 100 and reducing the difficulty of processing.

[0078] As another embodiment, the first end ring 140, the second end ring 150 and the conductive component 130 are all made of copper material. The conductive component 130 is a plurality of copper bars connected between the first end ring 140 and the second end ring 150. The first end ring 140, the second end ring 150 and the plurality of copper bars are fixed by welding or the like, thereby forming a structure stably connected to the rotor core 120.

[0079] Reference Fig. 9 and Fig.10 As shown, Fig. 9 is a schematic diagram of the structure of a motor according to an embodiment of the present invention, Fig.10 The figure is a partial cross-sectional schematic diagram of a motor according to an embodiment of the present invention. It is understandable that the motor of the present embodiment is a plastic-encapsulated motor, and the stator assembly is a plastic-encapsulated stator 300. By plastic-encapsulating the magnetic field sensing device 200 including the Hall sensor 210 and the circuit board 220 and the plastic-encapsulated stator 300 in one piece, the installation accuracy of the Hall sensor 210 can be higher and the installation structure can be more stable, thereby improving the detection accuracy of the Hall sensor 210 and the stability of the motor; and the axial size of the motor can be effectively reduced.

[0080] Continue to refer to Fig.10 As shown, it can be understood that the motor also includes a first end cover 400 and a second end cover 500, and the first end cover 400 and the second end cover 500 are respectively located at the two ends of the motor along the axial direction of the rotor core 120, and the first end cover 400 and the second end cover 500 are both installed with bearings, and the two ends of the rotating shaft 110 are respectively rotatably connected to the two bearings, so that the rotor assembly 100 can achieve stable rotation.

[0081] In this embodiment, the first end cover 400 is integrally molded with one end of the plastic-encapsulated stator 300. The other end of the plastic-encapsulated stator 300 is provided with an opening (not shown in the figure), and the rotor assembly 100 can be inserted and installed into the inner cavity of the plastic-encapsulated stator 300 through the opening. The second end cover 500 is used to cover the opening. For example, the second end cover 500 can be interference-fitted with the inner side surface 310 of the plastic-encapsulated stator 300, so as to achieve a stable connection between the second end cover 500 and the plastic-encapsulated stator 300. With the above structure, the second end cover 500 does not occupy the axial space of the plastic-encapsulated stator 300, which is conducive to increasing the stacking thickness of the stator core and improving the performance of the motor.

[0082] It can be understood that the second end cover 500 and the magnetic ring 170 are respectively located at the two ends of the rotor assembly 100 along the axial direction of the rotor core 120, so that the internal structure layout of the plastic-encapsulated motor of this embodiment is more reasonable, the structure is more reliable, and the assembly is more efficient.

[0083] It should be noted that the second end cover 500 can also be positioned and connected to the plastic-encapsulated stator 300 by bonding, clamping, etc., so that the second end cover 500 is fixedly connected to the plastic-encapsulated stator 300, and the specific method is not specifically limited here.

[0084] A household appliance according to an embodiment of the present invention comprises the motor of the above embodiment. The household appliance may be a wall mounted air conditioner, a cabinet air conditioner, a mobile air conditioner, a window air conditioner, etc., which are not specifically limited here. The present invention is a household appliance according to an embodiment, which adopts the motor of the first embodiment. The motor reduces the occupation of the axial space of the motor by the magnetic ring 170 by arranging the magnetic ring 170 in the groove 160 of the first end ring 140, and arranging the Hall sensor 210 along the axial direction of the rotor core 120 with the magnetic ring 170 at intervals, thereby saving the axial space of the motor under the condition that the size of the motor shell is limited, and improving the output power of the motor, thereby improving the load capacity of the motor.

[0085] The first end ring 140 is provided with a first protrusion 180 and a second protrusion 190 located on both sides of the groove 160 along the radial direction of the rotor core 120. The width of the surface of the first protrusion 180 along the radial direction of the rotor core 120 is d12, and the width of the surface of the second protrusion 190 along the radial direction of the rotor core 120 is d32, satisfying: |d12-d32|≤6mm. For a motor that meets the above parameter range, the width of the surface of the first protrusion 180 and the width of the surface of the second protrusion 190 are set to be substantially equal, so that the magnetic flux of the magnetic field of the first protrusion 180 entering the Hall sensor 210 is equal to the magnetic flux of the magnetic field of the second protrusion 190 entering the Hall sensor 210, and the magnetic flux lines generated by the magnetic field of the first protrusion 180 and the magnetic flux lines generated by the magnetic field of the second protrusion 190 are in opposite directions, so that the magnetic flux of the magnetic field of the first protrusion 180 and the magnetic field of the second protrusion 190 entering the Hall sensor 210 respectively cancel each other, avoiding the magnetic field of the first protrusion 180 and the magnetic field of the second protrusion 190 interfering with the detection of the magnetic field of the magnetic ring 170 by the Hall sensor 210, thereby achieving the effect of avoiding the magnetic field of the motor interfering with the magnetic field of the magnetic ring 170, and further achieving the purpose of stabilizing the magnetic field frequency of the Hall sensor 210. The motor of this embodiment makes the signal fluctuation of the Hall sensor 210 at a relatively small level, ensuring the accuracy of the speed signal of the motor.

[0086] Since the air conditioner adopts all the technical solutions of the motor of the above embodiment, it has at least all the beneficial effects brought by the technical solutions of the above embodiment, which will not be described in detail here.

[0087] The embodiments of the present invention are described in detail above with reference to the accompanying drawings, but the present invention is not limited to the above embodiments, and various changes can be made within the knowledge scope of ordinary technicians in the relevant technical field without departing from the purpose of the present invention.

Claims

1. A motor, characterized in that include: A stator assembly having a receiving cavity; A rotor assembly is rotatably disposed in the accommodating cavity, the rotor assembly comprises a rotor core, a rotor end ring and a magnetic field generating component, the rotor end ring is connected to one axial end of the rotor core, an end of the rotor end ring away from the rotor core is provided with a groove, and the magnetic field generating component is disposed in the groove; A magnetic field induction device, the magnetic field induction device comprising a magnetic field induction device and a circuit board connected to the magnetic field induction device, the magnetic field induction device and the magnetic field generating component are arranged at intervals along the axial direction of the rotor core; Wherein, the rotor end ring is further provided with a first protrusion and a second protrusion, the first protrusion is located on a side of the groove away from the center of the rotor core, and the second protrusion is located on a side of the groove toward the center of the rotor core; The width of the surface of the first protrusion along the radial direction of the rotor core is d12, and the width of the surface of the second protrusion along the radial direction of the rotor core is d32; along the axial direction of the rotor core, the distance between the magnetic field generating component and the magnetic field sensing device is d1; the surface of the magnetic field generating component includes a third outer contour line and a third inner contour line arranged at intervals, and along the radial direction of the rotor core, the distance between the midline of the third outer contour line and the third inner contour line and the geometric center of the magnetic field sensing device is d2, satisfying:

2. The motor according to claim 1, characterized in that: The width d12 of the surface of the first protrusion along the radial direction of the rotor core and the width d32 of the surface of the second protrusion along the radial direction of the rotor core satisfy: |d12-d32|≤6mm.

3. The motor according to claim 1, characterized in that: The plane where the surface of the first protrusion lies is perpendicular to the axial direction of the rotor core. The surface of the first protrusion includes a first outer contour line and a first inner contour line that are spaced apart. The first outer contour line and the first inner contour line enclose a closed annular plane.

4. The motor according to claim 1, characterized in that: The plane where the surface of the second protrusion lies is perpendicular to the axial direction of the rotor core. The surface of the second protrusion includes a second outer contour line and a second inner contour line that are spaced apart. The second outer contour line and the second inner contour line enclose a closed annular plane.

5. The motor according to claim 1, characterized in that: Along the axial direction of the rotor core, the distance between the magnetic field generating component and the magnetic field sensing device is d1, which satisfies: <d1≤3mm。 6. The motor according to claim 1, characterized in that: The surface of the magnetic field generating component includes a third outer contour line and a third inner contour line arranged at intervals. Along the radial direction of the rotor core, the distance between the midline of the third outer contour line and the third inner contour line and the geometric center of the magnetic field sensing device is d2; the width of the surface of the magnetic field generating component along the radial direction of the rotor core is d3, satisfying: 0≤d2≤1 / 4·d3.

7. The motor according to claim 1, characterized in that: The surface of the magnetic field generating component includes a third outer contour line and a third inner contour line that are spaced apart, the third outer contour line and the third inner contour line are both circular, and the third outer contour line and the third inner contour line enclose each other to form a closed circular plane.

8. The motor according to claim 1, characterized in that: The magnetic field sensing device is a Hall sensor.

9. The motor according to claim 1, characterized in that: The rotor assembly further includes a conductive component. Two rotor end rings are provided and are respectively connected to two axial ends of the rotor core. The conductive component is connected between the two rotor end rings.

10. The motor according to claim 9, characterized in that: The rotor end ring and the conductive component are integrally manufactured and formed.

11. The motor according to claim 1, characterized in that: The stator assembly and the magnetic field induction device are plastic-sealed.

12. The motor according to claim 11, characterized in that: The motor further comprises an end cover positioned and mounted with the stator assembly, wherein the end cover and the magnetic field generating component are respectively located at two ends of the rotor assembly along the axial direction of the rotor core.

13. The motor according to claim 1, characterized in that: A surface of the magnetic field generating component protrudes from a surface of the first protrusion and a surface of the second protrusion.

14. A household appliance, characterized in that: A motor comprising any one of claims 1 to 13.

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