Single-phase permanent magnet motor and vacuum cleaner having the same

Abstract

The present invention provides a single-phase permanent magnet motor and a vacuum cleaner having the same. The single-phase permanent magnet motor includes a first type of stator teeth; a second type of stator teeth, the first type of stator teeth and the second type of stator teeth are arranged to form an accommodating cavity for accommodating a rotor portion; a gradient air gap thickness is formed between one of the first type of stator teeth and the second type of stator teeth and the rotor portion, and a uniform air gap thickness is formed between the other of the first type of stator teeth and the second type of stator teeth and the rotor portion. By providing two types of stator tooth structures and forming different air gap structures between the two types of stator teeth and the rotor portion, the electromagnetic torque and the cogging torque of the motor are staggered, thereby solving the problem of the starting dead point of the single-phase motor. Compared with a simple asymmetric tooth structure, this structure can greatly improve the starting ability of the motor, reduce the starting current of the motor, and eliminate the problem of the dead point of the motor starting in the prior art.

Description

Technical Field

[0001] The present invention relates to the technical field of motor equipment, and in particular to a single-phase permanent magnet motor and a vacuum cleaner having the same. Background Art

[0002] Single-phase permanent magnet motors have single-phase windings, requiring fewer switching devices to drive the main circuit, resulting in lower control system hardware costs. However, single-phase permanent magnet motors suffer from a starting dead point problem. The armature magnetic field generated by the stator core of a single-phase permanent magnet motor is a pulsating field, and the resulting electromagnetic torque has a zero point. Without special motor construction, the motor's rest position (where the cogging torque is zero) coincides with the zero electromagnetic torque point. At this point, regardless of the current flowing through the armature winding, the motor only generates force in the direction of the rotor diameter, with the tangential force being zero. Consequently, the motor cannot start, resulting in a starting dead point problem.

[0003] To address the starting dead point issue, existing technologies employ a misaligned tooth structure, staggering the zero point of the motor's cogging torque and the zero point of the electromagnetic torque. This allows tangential torque to be generated even when the motor is parked, addressing the starting issues of single-phase permanent magnet motors. For example, by designing an asymmetrical stator tooth structure, the air gap structure of the stator teeth is uniform, resulting in lower cogging torque and significantly reducing the motor's output torque pulsation. However, this structure also has drawbacks: the motor's starting torque is low, requiring a higher starting current. Summary of the Invention

[0004] The main purpose of the present invention is to provide a single-phase permanent magnet motor and a vacuum cleaner having the same, so as to solve the problem of dead point during motor starting in the prior art.

[0005] To achieve the above-mentioned objective, according to one aspect of the present invention, a single-phase permanent magnet motor is provided, comprising: first-class stator teeth; second-class stator teeth, wherein the first-class stator teeth and the second-class stator teeth are arranged to form an accommodating cavity for accommodating a rotor portion; a gradient air gap thickness is formed between one of the first-class stator teeth and the second-class stator teeth and the rotor portion, and a uniform air gap thickness is formed between the other of the first-class stator teeth and the rotor portion, wherein there are a plurality of first-class stator teeth and a plurality of second-class stator teeth, and in any arrangement, among any two adjacent stator teeth, there is at least one group of two adjacent stator teeth whose geometric center lines along the radial direction of the rotor portion form a central angle not equal to 2π / s when connected to the geometric center line of the rotor portion, where s is the total number of the first-class stator teeth and the second-class stator teeth.

[0006] Furthermore, a central angle corresponding to a first contour line of the end surface of the first type of stator tooth facing the rotor part is smaller than a central angle corresponding to a second contour line of the end surface of the second type of stator tooth facing the rotor part.

[0007] Furthermore, a gradually varying air gap thickness is formed between the first type of stator teeth and the rotor portion, and a uniform air gap thickness is formed between the second type of stator teeth and the rotor portion.

[0008] Furthermore, there are multiple first-class stator teeth and multiple second-class stator teeth, and the central angle formed by the connection between the geometric center line of any two adjacent stator teeth along the radial direction of the rotor part and the geometric center of the rotor part is not equal to 2π / s, where s is the total number of first-class stator teeth and second-class stator teeth.

[0009] Furthermore, the number of the first type of stator teeth is the same as the number of the second type of stator teeth, wherein s=2n, and the plurality of first type of stator teeth and the plurality of second type of stator teeth are alternately arranged.

[0010] Furthermore, s=4, and a central angle formed by connecting the geometric center line of the first type of stator teeth, the geometric center line of the second type of stator teeth, and the geometric center of the rotor portion is not equal to 2π / s.

[0011] Furthermore, the geometric center line of the first contour line along the radial direction of the rotor part is used as a reference line, and the angle of 2π / s along the rotation direction of the rotor part is used as an offset baseline. An offset angle θ is formed between the geometric center line of the second contour line along the radial direction of the rotor part and the offset baseline, wherein θ=2 / (ab), 0<θ<π / 2-α2, α2 is the center angle formed by the line connecting the two ends of the first contour line and the geometric center of the rotor part (30), b is the center angle formed by the line connecting the offset baseline, the front end of the stator tooth where the offset baseline is located, and the geometric center of the rotor part, and a is the center angle formed by the line connecting the rear end of the stator tooth where the offset baseline is located, the offset baseline, and the geometric center of the rotor part.

[0012] Furthermore, along the rotation direction of the rotor part, the thickness of the air gap formed between the first type of stator teeth and the rotor part is set to gradually decrease.

[0013] Furthermore, the minimum air gap thickness formed between the first type of stator teeth and the rotor portion is g1, and the maximum air gap thickness formed between the first type of stator teeth and the rotor portion is g2, wherein 1.2g1<g2<2.2g1.

[0014] Furthermore, the single-phase permanent magnet motor also includes: third-type stator teeth, the third-type stator teeth, the first-type stator teeth and the second-type stator teeth are alternately arranged in sequence along the circumference of the rotor part, and a uniform air gap thickness is formed between the third-type stator teeth and the rotor part, and the air gap thickness formed between the third-type stator teeth and the rotor part is greater than or less than the air gap thickness formed between the second-type stator teeth and the rotor part.

[0015] Furthermore, multiple first-class stator teeth are arranged adjacent to each other, multiple second-class stator teeth are arranged adjacent to each other, or at least two second-class stator teeth among the multiple second-class stator teeth form a stator teeth group, and at least one stator teeth group is arranged between two first-class stator teeth.

[0016] Furthermore, the central angle formed by the geometric center lines of adjacent first-type stator teeth is 2π / s.

[0017] Furthermore, based on the geometric center line of the first type of stator teeth, a central angle formed by a geometric center line of an adjacent second type of stator teeth along the rotation direction of the rotor portion and the geometric center line of the rotor portion is less than 2π / s.

[0018] Furthermore, based on the geometric center line of the second type of stator teeth, a central angle formed by a geometric center line of the adjacent first type of stator teeth along the rotation direction of the rotor portion and the geometric center line of the rotor portion is greater than 2π / s.

[0019] Furthermore, the number of the first type of stator teeth and the number of the second type of stator teeth are an even number, and the number of the first type of stator teeth is different from the number of the second type of stator teeth.

[0020] According to another aspect of the present invention, a vacuum cleaner is provided, comprising a single-phase permanent magnet motor, wherein the single-phase permanent magnet motor is the single-phase permanent magnet motor described above.

[0021] The technical solution of the present invention addresses the starting dead point problem of single-phase motors by providing two types of stator tooth structures, each with different air gap structures between the two types of stator teeth and the rotor. This staggers the electromagnetic torque and cogging torque of the motor. Furthermore, the central angle formed by the connection between the radial geometric centerline of at least one pair of adjacent stator teeth in the second type of stator teeth and the geometric center of the rotor is set to be unequal to 2π / s. Compared to a simple asymmetric tooth structure, this structure significantly improves the motor's starting capability, reduces the starting current, and eliminates the dead point problem of motor starting in the prior art. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The accompanying drawings, which constitute part of this application, are intended to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are intended to explain the present invention and do not constitute an undue limitation of the present invention. In the accompanying drawings:

[0023] Figure 1 It shows a structural schematic diagram of a first embodiment of a single-phase permanent magnet motor according to the present invention;

[0024] Figure 2 It shows a structural schematic diagram of a second embodiment of a single-phase permanent magnet motor according to the present invention;

[0025] Figure 3 shows a structural schematic diagram of a third embodiment of a single-phase permanent magnet motor according to the present invention;

[0026] Figure 4 shows a structural schematic diagram of a fourth embodiment of a single-phase permanent magnet motor according to the present invention;

[0027] Figure 5 shows a structural schematic diagram of a fifth embodiment of a single-phase permanent magnet motor according to the present invention;

[0028] Figure 6 FIG. 1 is a structural schematic diagram of a sixth embodiment of a single-phase permanent magnet motor according to the present invention.

[0029] The above drawings include the following reference numerals:

[0030] 10. First type stator teeth;

[0031] 20. Second type of stator teeth;

[0032] 30. Rotor; 31. Rotating shaft; 32. Permanent magnet;

[0033] 40. Third type of stator teeth. DETAILED DESCRIPTION

[0034] It should be noted that, in the absence of conflict, the embodiments and features of the embodiments in this application can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0035] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, they indicate the presence of features, steps, operations, devices, components and / or combinations thereof.

[0036] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that the terms used in this way are interchangeable where appropriate, so that the embodiments of the present application described herein can, for example, be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0037] Now, exemplary embodiments according to the present application will be described in more detail with reference to the accompanying drawings. However, these exemplary embodiments can be implemented in a variety of different forms and should not be interpreted as being limited to the embodiments described herein. It should be understood that these embodiments are provided to make the disclosure of this application thorough and complete, and to fully convey the concepts of these exemplary embodiments to those of ordinary skill in the art. In the accompanying drawings, for the sake of clarity, the thickness of layers and regions may be exaggerated, and the same reference numerals are used to represent the same devices, and thus their descriptions will be omitted.

[0038] Combine Figures 1 to 6 As shown, according to a specific embodiment of the present application, a single-phase permanent magnet motor is provided.

[0039] Specifically, if Figure 1 As shown, the single-phase permanent magnet motor includes first-type stator teeth 10 and second-type stator teeth 20. The first-type stator teeth 10 and the second-type stator teeth 20 enclose a cavity for accommodating a rotor portion 30. A gradient air gap thickness is formed between one of the first-type stator teeth 10 and the second-type stator teeth 20 and the rotor portion 30, while a uniform air gap thickness is formed between the other of the first-type stator teeth 10 and the second-type stator teeth 20 and the rotor portion 30. There are multiple first-type stator teeth 10 and multiple second-type stator teeth 20. In any arrangement, among any two adjacent stator teeth, there is at least one set of two adjacent stator teeth whose geometric center lines along the radial direction of the rotor portion 30 form a central angle with the geometric center of the rotor portion 30 that is not equal to 2π / s, where s is the total number of first-type stator teeth 10 and second-type stator teeth 20.

[0040] In this embodiment, two types of stator teeth are provided, each forming a different air gap between the two types of stator teeth and the rotor. This staggers the electromagnetic torque and cogging torque of the motor. Furthermore, regardless of the arrangement of the plurality of first-type stator teeth 10 and the plurality of second-type stator teeth 20, the central angle formed by the connection of the geometric centerline of at least one pair of adjacent stator teeth along the radial direction of the rotor 30 and the geometric center of the rotor 30 is ensured to be unequal to 2π / s. This solves the problem of a dead point during starting in a single-phase motor. Compared to a simple asymmetric tooth structure, this structure significantly improves the motor's starting capability, reduces the motor's starting current, and eliminates the dead point problem encountered in conventional motor starting techniques.

[0041] The central angle corresponding to the first contour line of the end surface of the first-type stator tooth 10 facing the rotor portion 30 is smaller than the central angle corresponding to the second contour line of the end surface of the second-type stator tooth 20 facing the rotor portion 30. A gradual air gap thickness is formed between the first-type stator tooth 10 and the rotor portion 30, while a uniform air gap thickness is formed between the second-type stator tooth 20 and the rotor portion 30. This arrangement improves the motor's output torque and enhances its starting capability.

[0042] There are multiple first-type stator teeth 10 and multiple second-type stator teeth 20. The central angle formed by the connection between the geometric centerline of any two adjacent stator teeth along the radial direction of the rotor portion 30 and the geometric center of the rotor portion 30 is not equal to 2π / s, where s is the total number of first-type stator teeth 10 and second-type stator teeth 20. This arrangement can further increase the output torque of the motor and improve the starting capability of the motor.

[0043] Specifically, the number of the first type of stator teeth 10 is the same as the number of the second type of stator teeth 20, wherein s=2n, and the plurality of first type of stator teeth 10 and the plurality of second type of stator teeth 20 are alternately arranged. wherein s=4, and the central angle formed by the connection of the geometric center line of the first type of stator teeth 10, the geometric center line of the second type of stator teeth 20, and the geometric center of the rotor portion 30 is not equal to 2π / s. Figure 2 As shown, A is the geometric center line of the stator tooth contour line, B is the offset baseline of the stator tooth, F is the rotor rotation direction of the rotor part, the geometric center line of the first contour line along the radial direction of the rotor part 30 is used as the reference line, and the offset baseline is formed when the angle is 2π / s along the rotation direction of the rotor part 30. The geometric center line of the second contour line along the radial direction of the rotor part 30 and the offset baseline form an offset angle θ, wherein θ=2 / (ab), 0<θ<π / 2-α2, α2 is the center angle formed by the line connecting the two ends of the first contour line and the geometric center of the rotor part (30), b is the center angle formed by the line connecting the offset baseline, the front end of the stator tooth where the offset baseline is located, and the geometric center of the rotor part 30, and a is the center angle formed by the line connecting the rear end of the stator tooth where the offset baseline is located, the offset baseline, and the geometric center of the rotor part 30. Along the rotation direction F of the rotor part 30, the thickness of the air gap formed between the first type of stator tooth 10 and the rotor part 30 is gradually reduced. This setting can improve the efficiency of the motor.

[0044] Furthermore, the minimum air gap thickness between the first-type stator teeth 10 and the rotor portion 30 is g1, and the maximum air gap thickness between the first-type stator teeth 10 and the rotor portion 30 is g2, where 1.2g1 < g2 < 2.2g1. This configuration can further increase the motor's output torque and improve its starting capability.

[0045] According to another embodiment of the present application, Figure 3 As shown, a single-phase permanent magnet motor is provided, which also includes third-type stator teeth 40. The third-type stator teeth 40, the first-type stator teeth 10, and the second-type stator teeth 20 are alternately arranged along the circumference of the rotor portion 30. A uniform air gap thickness is formed between the third-type stator teeth 40 and the rotor portion 30, and the air gap thickness formed between the third-type stator teeth 40 and the rotor portion 30 is greater or less than the air gap thickness formed between the second-type stator teeth 20 and the rotor portion 30. The use of three different stator tooth structures results in different air gap thicknesses between the stator teeth and the rotor portion, which effectively improves the efficiency of the motor.

[0046] like Figure 4 As shown, a plurality of first-type stator teeth 10 are arranged adjacent to each other, and a plurality of second-type stator teeth 20 are arranged adjacent to each other. Alternatively, as shown Figure 5 As shown, at least two of the plurality of second-type stator teeth 20 form a stator teeth group, and at least one stator teeth group is provided between two first-type stator teeth 10. This arrangement can also increase the output torque of the motor and solve the problem of starting dead point in the motor in the prior art.

[0047] In this embodiment, the central angle formed by the geometric centerlines of adjacent first-class stator teeth 10 can be set to 2π / s. Taking the geometric centerline of the first-class stator teeth 10 as a reference, the central angle formed by the geometric centerline of the rotor portion 30 along the rotation direction of the rotor portion 30 to the adjacent second-class stator teeth 20 and the geometric centerline of the rotor portion 30 is less than 2π / s. Taking the geometric centerline of the second-class stator teeth 20 as a reference, the central angle formed by the geometric centerline of the rotor portion 30 along the rotation direction of the rotor portion 30 to the adjacent first-class stator teeth 10 and the geometric centerline of the rotor portion 30 is greater than 2π / s. This setting can also increase the output torque of the motor and improve the practicality of the motor. The number of first-class stator teeth 10 and the number of second-class stator teeth 20 are an even number, and the number of first-class stator teeth 10 is different from the number of second-class stator teeth 20.

[0048] The single-phase permanent magnet motor in the above embodiment can also be used in the technical field of vacuum cleaner equipment. That is, according to another aspect of the present invention, a vacuum cleaner is provided, including a single-phase permanent magnet motor, which is the single-phase permanent magnet motor in the above embodiment.

[0049] Specifically, the single-phase permanent magnet motor provided by the present application has a stator core comprising at least two different tooth structures, and the difference in the tooth structure must simultaneously satisfy the difference in the air gap structure and the difference in the size of the central angle of the tooth contour line. The air gap structure corresponding to the different stator tooth structures includes at least one gradient air gap structure and at least one uniform air gap structure. For different stator tooth structures, the corresponding central angles have different sizes with the rotor center as the circle center reference. On the stator teeth of the motor, among all two adjacent stator teeth, there is at least one group of adjacent stator teeth, and the central angle between the geometric center lines of the contour lines of the two facing the rotor part is not equal to 2π / s. The central angle of the stator tooth corresponding to the gradient air gap structure is smaller, that is, the air gap structure of the small tooth is a gradient air gap, and the air gap structure of the large tooth is a uniform air gap, wherein the central angle of the small tooth contour line is a2, and the central angle of the large tooth contour is a1. The large and small teeth are arranged alternately in a pair along the rotation direction of the motor. The same stator teeth are obtained by a single stator tooth passing through a circular array around the center of the rotor.

[0050] The air gap of the gradient air gap structure changes as follows: along the rotation direction of the motor, the air gap thickness gradually decreases, that is, g1 < g2, the minimum air gap length on the air gap gradient tooth is g1, and the maximum air gap length is g2, where 1.2g1 < g2 < 2.2g1.

[0051] Because single-phase permanent magnet motors generate a pulsating magnetic field, they present starting problems. The motor's stop position is typically where the cogging torque is zero. If the motor's electromagnetic torque is also zero at this point, then regardless of the current flowing through the motor, the rotor will only generate radial force, failing to generate tangential starting torque. Consequently, the motor will fail to start.

[0052] This application proposes a new single-phase permanent magnet motor. By employing an asymmetric air gap structure and tooth offset, the motor's electromagnetic torque and cogging torque are offset by an angle, thereby resolving the problem of single-phase motor starting dead points. Compared to a simple asymmetric tooth structure, this structure significantly improves the motor's starting capability and reduces the starting current.

[0053] like Figure 2 As shown, the motor includes two different tooth structures, one of which is a uniform air gap structure and the other is a gradient air gap structure. The stator teeth of the two structures are alternately distributed in a 1-to-1 manner along the rotation direction of the motor.

[0054] Taking the gradient air gap stator teeth as a reference, adjacent stator teeth in the direction of motor rotation have a uniform air gap structure. The angle between the center point of the air gap and the rotor axis in both structures is γ, where γ is less than 2π / s. Both the gradient air gap structure and the uniform air gap structure with tooth offset can create a phase difference between the motor's cogging torque and electromagnetic torque, eliminating the motor's starting dead point. The combination of these two structures can produce a synergistic effect, significantly improving the motor's starting torque and reducing the starting current. Furthermore, the offset angle of the uniform air gap stator teeth needs to be appropriately set. Excessive offset angles reduce the distance between the two stator teeth, resulting in magnetic leakage and reduced motor output capacity. However, if the offset angle is too small, the effective starting torque generated per unit current is small, resulting in a higher starting current.

[0055] Taking the center line of the contour line of the tooth part (small tooth) where the gradual air gap is located as a reference, the straight line with an angle of 2π / s with the center line of the small tooth contour line is the tooth offset baseline of the large tooth. The offset angle of the uniform air gap stator tooth (large tooth) is θ=2 / (ab), as shown in Figure 2 As shown in the figure, the range of θ is 0<θ<π / 2-a2, where a2 is the central angle spanned by the motor tooth profile. The air gap thickness gradually decreases along the motor's rotation direction, i.e., g1<g2, and 1.2g1<g2<2.2g1.

[0056] Because the cogging torque and electromagnetic torque of the gradient air gap are both offset toward the smaller stator air gap, and the cogging torque offset angle is larger, in order to obtain a larger starting angle and reduce starting difficulty, the gradient air gap thickness gradually decreases along the direction of motor rotation.

[0057] Furthermore, the motor can also include another air gap structure that is different from the previous two. In order to further improve the starting ability of the motor, a uniform air gap structure is added, but the air gap thickness is different from the previous uniform air gap thickness. In this case, the motor includes one gradient air gap and two uniform air gap structures with different air gap thicknesses. The three stator tooth structures are arranged alternately in a 1-to-1 manner along the rotation direction of the motor. Figure 3 As shown in the figure, the combination of these three tooth structures can enable the single-phase permanent magnet motor to obtain a larger starting torque and the motor has a better starting ability.

[0058] For the two stator tooth arrangements of the motor, for 4 or more stator teeth, the two stator teeth are not interlaced with each other. The motor stator teeth as a whole include two stator tooth sets, that is, each stator tooth set contains only the same type of stator teeth (1...1122...2 structure, 1 and 2 represent two different stator teeth). For example Figure 4 shown.

[0059] The centerline angle γ1 between the contours of two adjacent stator teeth of the same structure is 2π / s. Taking the contour centerline of the small tooth (the tooth with the smaller central angle) as a reference, the centerline angle γ2 between the contour centerline of the adjacent large tooth (the tooth with the larger central angle) in the direction of motor rotation and the centerline of the small tooth is less than 2π / s. Taking the centerline of the large tooth contour as a reference, the centerline angle γ3 between the contour centerline of the adjacent small tooth in the direction of motor rotation and the centerline of the large tooth contour is greater than 2π / s. This configuration results in a motor with reduced cogging torque ripple and a higher starting torque, thereby reducing starting current.

[0060] According to another embodiment of the present application, Figure 5 As shown, the arrangement of the two stator teeth can be set as follows: the two stator teeth are interspersed and there are also stator tooth sets, each stator tooth set contains only the same type of stator teeth, and the number of stator teeth in the stator tooth set is greater than or equal to 2, and the number of the two types of stator teeth is an even number.

[0061] The yoke of the motor stator core may include a closed ring, a closed frame or an open frame structure, such as a C-type and a U-type. Figure 6 shown.

[0062] For ease of description, spatially relative terms such as "above," "above," "on the upper surface of," and "upper" may be used herein to describe the spatial positional relationship of a device or feature to other devices or features as shown in the figures. It should be understood that spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if a device in a drawing is inverted, a device described as "above" or "on top of" another device or structure would then be positioned as "below" or "below" the other device or structure. Thus, the exemplary term "above" can include both the "above" and "below" orientations. The device may also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatially relative descriptions used herein should be interpreted accordingly.

[0063] In addition to the above, it should be noted that references to "one embodiment," "another embodiment," "an embodiment," and the like in this specification refer to specific features, structures, or characteristics described in conjunction with that embodiment as included in at least one embodiment generally described in this application. The appearance of the same expression in multiple places in the specification does not necessarily refer to the same embodiment. Furthermore, when a specific feature, structure, or characteristic is described in conjunction with any embodiment, it is intended that such feature, structure, or characteristic, when implemented in conjunction with other embodiments, also falls within the scope of the present invention.

[0064] In the above embodiments, the description of each embodiment has its own focus. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0065] The foregoing description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention.

Claims

1. A single-phase permanent magnet motor, characterized in that: include: First type stator teeth (10); Second-type stator teeth (20), wherein the first-type stator teeth (10) and the second-type stator teeth (20) are arranged to form an accommodating cavity for accommodating a rotor portion (30); A gradient air gap thickness is formed between one of the first type of stator teeth (10) and the second type of stator teeth (20) and the rotor portion (30), and a uniform air gap thickness is formed between the other of the first type of stator teeth (10) and the second type of stator teeth (20) and the rotor portion (30); wherein the first type of stator teeth (10) is a plurality, and the second type of stator teeth (20) is a plurality, and in any arrangement, among any two adjacent stator teeth, there is at least one group of two adjacent stator teeth whose geometric center lines along the radial direction of the rotor part (30) form a central angle not equal to 2π / s when connected to the geometric center of the rotor part (30), where s is the total number of the first type of stator teeth (10) and the second type of stator teeth (20); The angle of the central angle corresponding to the first contour line of the end surface of the first type of stator tooth (10) facing the rotor part (30) is smaller than the angle of the central angle corresponding to the second contour line of the end surface of the second type of stator tooth (20) facing the rotor part (30); The geometric center line of the first contour line along the radial direction of the rotor part (30) is used as a reference line, and the angle of 2π / s along the rotation direction of the rotor part (30) is used as an offset baseline. The geometric center line of the second contour line along the radial direction of the rotor part (30) and the offset baseline form an offset angle θ, wherein θ=(ab) / 2, 0<θ<π / 2-α2, α2 is the central angle formed by the line connecting the two ends of the first contour line and the geometric center of the rotor part (30), b is the central angle formed by the line connecting the offset baseline, the front end of the stator tooth where the offset baseline is located, and the geometric center of the rotor part (30), and a is the central angle formed by the line connecting the rear end of the stator tooth where the offset baseline is located, the offset baseline, and the geometric center of the rotor part (30); a plurality of the first-type stator teeth (10) are arranged adjacent to each other.

2. The single-phase permanent magnet motor according to claim 1, characterized in that: A gradient air gap thickness is formed between the first type of stator teeth (10) and the rotor portion (30), and a uniform air gap thickness is formed between the second type of stator teeth (20) and the rotor portion (30).

3. The single-phase permanent magnet motor according to claim 1, characterized in that: The number of the first type of stator teeth (10) is the same as the number of the second type of stator teeth (20), wherein s=2n, and a plurality of the first type of stator teeth (10) and a plurality of the second type of stator teeth (20) are alternately arranged.

4. The single-phase permanent magnet motor according to claim 2, characterized in that: s=4, and a central angle formed by connecting the geometric center line of the first type of stator teeth (10), the geometric center line of the second type of stator teeth (20), and the geometric center of the rotor part (30) is not equal to 2π / s.

5. The single-phase permanent magnet motor according to claim 1, characterized in that: Along the rotation direction of the rotor part (30), the thickness of the air gap formed between the first type of stator teeth (10) and the rotor part (30) is arranged to gradually decrease.

6. The single-phase permanent magnet motor according to claim 2 or 5, characterized in that: The minimum air gap thickness formed between the first type of stator teeth (10) and the rotor part (30) is g1, and the maximum air gap thickness formed between the first type of stator teeth (10) and the rotor part (30) is g2, wherein 1.2g1<g2<2.2g1.

7. The single-phase permanent magnet motor according to claim 2, characterized in that: The single-phase permanent magnet motor further comprises: A third type of stator teeth (40), wherein the third type of stator teeth (40), the first type of stator teeth (10) and the second type of stator teeth (20) are alternately arranged in sequence along the circumference of the rotor portion (30), a uniform air gap thickness is formed between the third type of stator teeth (40) and the rotor portion (30), and the air gap thickness formed between the third type of stator teeth (40) and the rotor portion (30) is greater than or less than the air gap thickness formed between the second type of stator teeth (20) and the rotor portion (30).

8. The single-phase permanent magnet motor according to claim 1, characterized in that: A plurality of the second-type stator teeth (20) are arranged adjacent to each other, or at least two of the second-type stator teeth (20) form a stator teeth group, and at least one of the stator teeth groups is arranged between two of the first-type stator teeth (10).

9. The single-phase permanent magnet motor according to claim 8, characterized in that: The central angle formed by the geometric center lines of adjacent first-type stator teeth (10) is 2π / s.

10. The single-phase permanent magnet motor according to claim 9, characterized in that: Taking the geometric center line of the first type of stator teeth (10) as a reference, a central angle formed by a geometric center line of the adjacent second type of stator teeth (20) along the rotation direction of the rotor part (30) and the geometric center line of the rotor part (30) is less than 2π / s.

11. The single-phase permanent magnet motor according to claim 10, characterized in that: With the geometric center line of the second type of stator teeth (20) as a reference, a central angle formed by the geometric center line of the first type of stator teeth (10) adjacent to the first type of stator teeth (10) along the rotation direction of the rotor part (30) and the geometric center line of the rotor part (30) is greater than 2π / s.

12. The single-phase permanent magnet motor according to claim 1, characterized in that: The number of the first type of stator teeth (10) and the number of the second type of stator teeth (20) are an even number, and the number of the first type of stator teeth (10) is different from the number of the second type of stator teeth (20).

13. A vacuum cleaner comprising a single-phase permanent magnet motor, characterized in that: The single-phase permanent magnet motor is the single-phase permanent magnet motor according to any one of claims 1 to 12.

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