An axial flux PCB motor

Abstract

This application discloses an axial flux PCB motor, relating to the field of motor technology, comprising a rotor, a stator core, and a winding structure. The winding structure forms multiple oblique channels distributed along its circumference. The stator core includes multiple oblique stator teeth arranged along its circumference, which are adapted to the oblique channels. Each oblique stator tooth passes through a corresponding oblique channel to magnetically couple with the rotor. The technical solution of this application, through the cooperation of multiple oblique channels arranged along the circumference of the winding structure and multiple oblique stator teeth arranged along the circumference of the stator core, forms an oblique pole structure. This causes the spatial phases of the harmonic magnetic fields of each layer of teeth to be misaligned and superimposed and canceled in the air gap, significantly reducing the amplitude of tooth harmonics and effectively suppressing torque pulsation and periodic electromagnetic excitation. This not only helps reduce the mechanical vibration and operating noise of the motor but also improves the motor's running stability and control accuracy.

Description

Technical Field

[0001] This application relates to the field of motor technology, and in particular to an axial flux PCB motor. Background Technology

[0002] Axial flux motors are widely used in fields with stringent requirements for space, lightweighting, and energy efficiency, such as new energy vehicles, electric aviation, and high-precision transmission, due to their advantages of short axial dimensions, high power and torque density, high efficiency, and excellent heat dissipation.

[0003] However, this type of motor uses an axial magnetic circuit coupling structure, which is prone to generating large torque pulsations. This not only reduces the smoothness of motor operation and control accuracy, but also causes periodic electromagnetic excitation, increases mechanical vibration and leads to high operating noise. Summary of the Invention

[0004] The purpose of this application is to provide an axial flux PCB motor, which aims to solve the technical problems of low control accuracy and high noise in existing axial flux motors.

[0005] To achieve the above objectives, this application provides an axial flux PCB motor, including a rotor, a stator core, and a winding structure. The winding structure forms a plurality of oblique channels distributed along its circumference. The stator core includes a plurality of oblique stator teeth arranged along its circumference. The oblique stator teeth are adapted to the oblique channels, and each oblique stator tooth passes through the corresponding oblique channel to magnetically couple with the rotor.

[0006] In one embodiment, the winding structure includes a plurality of PCB winding layers stacked along the axial direction of the stator core. Each PCB winding layer has a plurality of mating holes along its circumference, and adjacent PCB winding layers are staggered so that the mating holes of each PCB winding layer are staggered. For each oblique channel, it is formed by stacking the corresponding mating holes on each PCB winding layer.

[0007] In one embodiment, all the inclined stator teeth are inclined along the circumference of the stator core, and all the inclined stator teeth have the same inclination angle.

[0008] In one embodiment, the stator core includes a first stator core and a second stator core, and the winding structure includes a first winding structure and a second winding structure. The first stator core and the second stator core are respectively located on both sides of the rotor, and the first winding structure and the second winding structure are respectively located on both sides of the rotor. The first winding structure is located between the first stator core and the rotor, and the second winding structure is located between the second stator core and the rotor. Each of the oblique stator teeth of the first stator core passes through the corresponding oblique channel on the first winding structure and is magnetically coupled to one side of the rotor, and each of the oblique stator teeth of the second stator core passes through the corresponding oblique channel on the second winding structure and is magnetically coupled to the other side of the rotor.

[0009] In one embodiment, the inclined stator teeth on the first stator core and the inclined stator teeth on the second stator core, which are on the same axial direction, have the same inclination direction.

[0010] In one embodiment, the inclined stator teeth on the first stator core and the inclined stator teeth on the second stator core, which are on the same axial direction, have opposite inclination directions.

[0011] In one embodiment, the number of PCB winding layers in the first winding structure is the same as the number of PCB winding layers in the second winding structure.

[0012] In one embodiment, the PCB winding layers of the first winding structure have the same structure as the PCB winding layers of the second winding structure.

[0013] In one embodiment, each of the PCB winding layers is a fractional-slot concentrated winding structure, and the conductive lines of each of the PCB winding layers are wound around the outer periphery of the corresponding mating holes, and each conductive line independently corresponds to one mating hole, so that the conductive line and the oblique stator tooth passing through the corresponding mating hole form a magnetic coupling circuit.

[0014] In one embodiment, the rotor includes a plurality of rotor blocks arranged circumferentially, the number of rotor blocks being less than the number of oblique stator teeth of the stator core.

[0015] The above-mentioned technical solution of this application has at least the following beneficial technical effects: The technical solution of this application forms a slanted pole structure by cooperating with multiple slanted channels arranged along the circumference of the winding structure and multiple slanted stator teeth arranged along the circumference of the stator core. This causes the spatial phase of the harmonic magnetic field of each layer of teeth to be misaligned and superimposed and canceled in the air gap, which greatly reduces the amplitude of tooth harmonics and effectively suppresses torque pulsation and periodic electromagnetic excitation. This not only helps to reduce the mechanical vibration and operating noise of the motor, but also improves the running stability and control accuracy of the motor. Attached Figure Description

[0016] Figure 1 This is an exploded structural diagram of an embodiment of the axial flux PCB motor provided in this application; Figure 2This is a schematic diagram of the overall assembly structure of an embodiment of the axial flux PCB motor provided in this application; Figure 3 This is a schematic diagram of the winding structure of an embodiment of the axial flux PCB motor provided in this application; Figure 4 This is a schematic diagram of the structure of an embodiment of the inclined stator teeth on the first stator core and the inclined stator teeth on the second stator core provided in this application, showing their respective inclination directions. Figure 5 This is a schematic diagram of another embodiment of the inclined stator teeth on the first stator core and the inclined stator teeth on the second stator core provided in this application.

[0017] Figure label: 1. Rotor; 11. Rotor block; 2. Stator core; 201. Oblique stator teeth; 21. First stator core; 22. Second stator core; 3. Winding structure; 301. Oblique channel; 302. PCB winding layer; 303. Mating hole; 31. First winding structure; 32. Second winding structure. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of this application clearer, the application will be further described in detail below with reference to specific embodiments and accompanying drawings. It should be understood that these descriptions are merely exemplary and not intended to limit the scope of this application. Furthermore, descriptions of well-known structures and technologies are omitted in the following description to avoid unnecessarily obscuring the concepts of this application.

[0019] The embodiments described in this application are only some, not all, of the embodiments described herein. All other embodiments obtained by those skilled in the art based on the embodiments described herein without inventive effort are within the scope of protection of this application.

[0020] In the description of this application, it should be noted that the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0021] Axial flux motors are widely used in fields with stringent requirements for space, lightweighting, and energy efficiency, such as new energy vehicles, electric aviation, and high-precision transmissions, due to their advantages of short axial dimensions, high power and torque density, high efficiency, and excellent heat dissipation. However, these motors employ an axial magnetic circuit coupling structure, which is prone to generating large torque ripples. This not only reduces the smoothness of motor operation and control accuracy but also induces periodic electromagnetic excitation, increasing mechanical vibration and leading to higher operating noise.

[0022] The root cause is that the periodic distribution of stator teeth creates a spatially wavy harmonic magnetic field in the air gap. In conventional stator structures, the peak values ​​of the magnetic fields formed by each tooth overlap and superimpose at the same axial position, directly leading to a significant increase in the amplitude of the harmonic magnetic field, which becomes the core cause of torque pulsation. At the same time, the inherent problems of uneven axial magnetic field distribution and large end leakage flux further aggravate the periodic fluctuations of electromagnetic harmonic distortion and radial magnetic pull. Under the superposition of multiple factors, significant torque pulsation is finally triggered, which not only greatly reduces the running stability and control accuracy of the motor, but also generates periodic electromagnetic excitation, further increasing mechanical vibration, and ultimately leading to high motor operating noise.

[0023] To address the aforementioned technical problems, this application provides an axial flux PCB motor. It should be noted that PCB refers to a printed circuit board. In one embodiment, please refer to... Figures 1 to 3 The axial flux PCB motor includes a rotor 1, a stator core 2, and a winding structure 3. The winding structure 3 has multiple oblique channels 301 distributed along its circumference. In a first embodiment, the oblique channels 301 are multiple inclined through-holes arranged along the circumference of the winding structure 3, each extending obliquely along the axial direction of the winding structure 3 and penetrating the entire thickness of the winding. In a second embodiment, the winding structure 3 includes multiple PCB winding layers 302 stacked along the axial direction of the stator core 2. Each PCB winding layer 302 has multiple mating holes 303 opened along its circumference, and adjacent PCB winding layers 302 are staggered so that the corresponding mating holes 303 of each PCB winding layer 302 are staggered. Each oblique channel 301 is formed by stacking corresponding mating holes 303 on each PCB winding layer 302. The tilt angle of the oblique channel 301 can be flexibly changed by adjusting the circumferential misalignment angle of the PCB winding layer 302. This results in stronger adaptability of the oblique pole parameters, more precise harmonic suppression and torque ripple optimization, and the multi-layer misalignment can further weaken the amplitude of the tooth harmonic magnetic field. The stator core 2 includes multiple oblique stator teeth 201 arranged along its own circumference. The oblique stator teeth 201 are adapted to the oblique channels 301, and each oblique stator tooth 201 passes through the corresponding oblique channel 301 to magnetically couple with the rotor 1.

[0024] The technical solution of this application will be described in detail below with reference to two specific embodiments in the first embodiment. In the first embodiment, please refer to... Figure 3 , Figure 3The diagram shows multiple PCB winding layers 302 stacked clockwise along the axial direction of the stator core 2. The total number of PCB winding layers 302 is n, and the total tilt angle of the oblique channel 301 is θ. The total tilt angle θ is achieved by accumulating the circumferential misalignment angles of the n PCB winding layers 302. That is, when the total tilt angle is θ, the interlayer misalignment angle ensures that after all layers are misaligned and stacked, the oblique channel 301 with a total tilt angle of θ is formed by the hole 303. At the same time, the oblique stator tooth 201 is also tilted clockwise along the axial direction of the stator core 2, and the tilt angle is θ, ensuring precise matching with the oblique channel 301. The specific formation process of the oblique channel 301 is as follows: The first PCB winding layer 302 is fixedly positioned along the axial direction of the stator core 2, with its mating hole 303 as the 0° reference position. The second PCB winding layer 302 is offset θ / n relative to the first one circumferentially, the third is offset θ / n relative to the second, and so on, with the kth (1≤k≤n) offset (k−1)×(θ / n) relative to the first, ultimately forming an oblique channel 301 with a total tilt angle of θ. Specifically, the total tilt angle θ can be 3°, 5°, or 8°, etc., and the total number of PCB winding layers n can be 6, 8, or 10, etc. The values ​​of the total tilt angle θ and the total number of layers n can be designed according to the actual needs of the motor and are not limited here.

[0025] Furthermore, in the second embodiment, multiple PCB winding layers 302 can also be stacked counterclockwise along the axial direction of the stator core 2 to form an oblique channel 301. Simultaneously, the oblique stator teeth 201 are also tilted counterclockwise along the axial direction of the stator core 2, and the tilt angle of the oblique stator teeth 201 is the same as the total tilt angle of the oblique channel 301, ensuring precise engagement between the oblique stator teeth 201 and the oblique channel 301. It should be noted that the formation principle of the oblique channel 301 in this embodiment is the same as that in the first embodiment, and will not be repeated here.

[0026] The technical solution of this application uses multiple oblique channels 301 arranged along the circumference of the winding structure 3 and multiple oblique stator teeth 201 arranged along the circumference of the stator core 2 to form an oblique pole structure, so that the spatial phase of the harmonic magnetic field of each layer of teeth is misaligned and superimposed and canceled in the air gap, which greatly reduces the amplitude of tooth harmonics and effectively suppresses torque pulsation and periodic electromagnetic excitation. This is beneficial to reducing the mechanical vibration and operating noise of the motor, and can also improve the running stability and control accuracy of the motor.

[0027] In one embodiment, all oblique stator teeth 201 are inclined around the stator core 2, and the inclination angle is the same as that of the oblique channel 301, thereby ensuring precise engagement between the oblique stator teeth 201 and the oblique channel 301. This embodiment, by inclining the oblique stator teeth 201 around the stator core 2 and ensuring that their inclination angle matches that of the oblique channel 301, achieves high-precision assembly between the stator teeth and the winding channel. This helps reduce the risk of assembly interference, improves magnetic circuit coupling stability, ensures uniform phase misalignment of the magnetic field of each PCB winding layer, effectively cancels tooth harmonics, further suppresses torque pulsation and operating noise, and improves motor control accuracy and operational smoothness.

[0028] In one embodiment, all the inclined stator teeth 201 have the same tilt angle, which facilitates precise matching with the inclined channel 301. By setting all the inclined stator teeth 201 to the same tilt angle, this embodiment can achieve unified adaptation and precise assembly between the inclined stator teeth 201 and the inclined channel 301. This simplifies the processing and assembly process, reduces manufacturing errors and assembly difficulty, and ensures that the magnetic circuit parameters corresponding to each stator tooth are uniform and consistent, improving the symmetry of the air gap magnetic field distribution and further enhancing the harmonic suppression effect and the stability of motor operation.

[0029] In one implementation, please refer to Figure 1 The stator core 2 includes a first stator core 21 and a second stator core 22, and the winding structure 3 includes a first winding structure 31 and a second winding structure 32. The first stator core 21 and the second stator core 22 are located on opposite sides of the rotor 1, and the first winding structure 31 and the second winding structure 32 are located on opposite sides of the rotor 1. The first winding structure 31 is located between the first stator core 21 and the rotor 1, and the second winding structure 32 is located between the second stator core 22 and the rotor 1. Each oblique stator tooth 201 of the first stator core 21 passes through a corresponding oblique channel 301 on the first winding structure 31 and is magnetically coupled to one side of the rotor 1. Each oblique stator tooth 201 of the second stator core 22 passes through a corresponding oblique channel 301 on the second winding structure 32 and is magnetically coupled to the other side of the rotor 1. This implementation method can form a bilaterally symmetrical axial magnetic circuit structure, which is beneficial to improve the power density and torque output capability of the motor, ensure a balanced magnetic field distribution, reduce vibration caused by unilateral magnetic pull, enhance the harmonic cancellation effect, further reduce operating noise, and improve the reliability and stability of the motor in long-term operation.

[0030] In one implementation, please refer to Figure 4For the oblique stator teeth 201 on the first stator core 21 and the second stator core 22, which are on the same axial direction, their inclination directions are the same. Specifically, looking along the axial direction of the stator core 2 towards the rotor 1, the oblique stator teeth 201 on the first stator core 21 are all inclined counterclockwise along the circumference of the stator core 2, and the oblique stator teeth 201 on the second stator core 22 are all inclined counterclockwise along the circumference of the stator core 2, that is, their inclination directions are the same. This implementation allows the dual magnetic circuits to form a coordinated oblique pole magnetic field distribution, which is beneficial to significantly reduce the harmonic amplitude of the air gap teeth, reduce torque pulsation and electromagnetic excitation, reduce mechanical vibration and operating noise, and at the same time improve the air gap magnetic field coupling efficiency, ensure the smooth operation and control accuracy of the motor, and adapt to the low-noise operating conditions such as high-precision transmission.

[0031] In one implementation, please refer to Figure 5 For the oblique stator teeth 201 on the first stator core 21 and the second stator core 22, which are on the same axial direction, their inclination directions are opposite. Specifically, looking along the axial direction of the stator core 2 towards the rotor 1, the oblique stator teeth 201 on the first stator core 21 are all inclined counterclockwise along the circumference of the stator core 2, and the oblique stator teeth 201 on the second stator core 22 are all inclined clockwise along the circumference of the stator core 2, that is, their inclination directions are opposite. This embodiment can increase the total misalignment angle between the two windings, which is beneficial to further disperse the air gap tooth harmonic magnetic field, enhance the harmonic cancellation effect, significantly reduce torque pulsation and electromagnetic excitation, reduce mechanical vibration and operating noise, and improve the operating performance of the motor under specific pole slot combinations, making it suitable for low-noise and high-precision application conditions.

[0032] In one embodiment, the number of PCB winding layers 302 in the first winding structure 31 is the same as the number of PCB winding layers 302 in the second winding structure 32. This allows the magnetic circuit structure and electromagnetic parameters on both sides of the rotor 1 to form a symmetrical match, which is beneficial to balance the distribution of the air gap magnetic field on both sides, reduce the fluctuation of magnetic pull on one side, enhance the harmonic suppression synergy effect of the multi-layer skew pole, improve the stability of torque output, and at the same time reduce electromagnetic vibration and operating noise, ensuring the overall smoothness and reliability of the motor operation.

[0033] In one embodiment, the PCB winding layers 302 of the first winding structure 31 have the same structure as the PCB winding layers 302 of the second winding structure 32. This embodiment allows the windings on both sides to adopt the same structure, with unified mold development and component processing, which helps to reduce mold opening and manufacturing costs. At the same time, it ensures precise matching of electromagnetic parameters of the magnetic circuits on both sides and balanced magnetic field distribution, further enhancing the harmonic suppression effect and improving the smoothness of motor operation.

[0034] In one embodiment, each PCB winding layer 302 is a fractional-slot concentrated winding structure 3. The conductive lines of each PCB winding layer 302 are wound around the outer periphery of the corresponding mating holes 303, and each conductive line independently corresponds to one mating hole 303, so that the conductive lines and the oblique stator teeth 201 passing through the corresponding mating holes 303 form a magnetic coupling circuit. Specifically, each PCB winding layer 302 has an integrated conductive line etched on its surface. The conductive line is wound around the outer periphery of each mating hole 303 distributed circumferentially, and the conductive line adopts a single-path independent corresponding layout, that is, a single complete conductive line only winds around the outer periphery of a single mating hole 303, without cross-hole winding or multiple lines sharing, so that each conductive line forms an independent winding unit. The center of the winding unit is coaxially set with the center of the corresponding mating hole 303, and the radial coverage of the winding unit matches the radial dimension of the mating hole 303, ensuring that the winding unit and the subsequently inserted oblique stator teeth 201 form an efficient magnetic coupling. When the oblique stator tooth 201 passes through the corresponding mating hole 303 on each PCB winding layer 302, the oblique stator tooth 201 will axially penetrate the conductive line winding unit on the outer periphery of the corresponding mating hole 303 in all PCB winding layers 302, so that the same oblique stator tooth 201 and the corresponding single conductive line in the axially stacked multi-layer PCB winding layers 302 form an integrated magnetic coupling circuit; and since each PCB winding layer 302 is a fractional slot concentrated winding structure 3, the conductive line winding unit on the outer periphery of adjacent mating holes 303 is distributed in fractional slot intervals. With the circumferential staggered arrangement of the multi-layer PCB winding layers 302, it can effectively shorten the winding end length, reduce winding copper loss, and improve the electromagnetic conversion efficiency of the motor. It can also further weaken the low-order harmonics in the air gap magnetic field through the slot pole matching characteristics of the fractional slots, forming a synergistic effect of harmonic suppression with the multi-layer oblique pole structure. Meanwhile, the winding direction, wire diameter, and number of turns of the conductive lines in each PCB winding layer 302 are kept consistent to ensure electromagnetic parameter matching of each layer of winding units in the same magnetic coupling circuit, avoiding magnetic circuit distortion caused by parameter differences. The conductive lines of adjacent PCB winding layers 302 are axially connected through pre-set vias in the PCB winding layers 302, so that multiple independent winding units form a continuous winding circuit, ensuring the continuity and stability of magnetic coupling. Ultimately, the oblique stator teeth 201 of the stator core 2, the fractional slot concentrated winding of the PCB winding layer 302, and the magnetic pole structure of the rotor 1 form an efficient and stable axial magnetic circuit coupling, which suppresses torque pulsation and vibration noise while ensuring the power density and torque density of the motor.

[0035] In one implementation, please refer to Figure 1The rotor 1 includes multiple rotor blocks 11 arranged circumferentially. The number of rotor blocks 11 is less than the number of oblique stator teeth 201 in the stator core 2. This can disperse low-order harmonics of the air gap magnetic field, suppress cogging torque, and help reduce periodic fluctuations in torque pulsation. Combined with the multi-layer oblique pole structure, it further weakens the amplitude of tooth harmonics, reduces electromagnetic vibration and operating noise, and improves motor control accuracy and operational stability. Specifically, this application... Figure 1 The image shows a 9-slot, 8-pole motor. In this motor, the stator has 9 teeth and the rotor 1 has 8 poles (i.e., 4 pairs of magnetic poles). There is also a 9-slot, 2-pole motor (not shown in the image). This motor has 9 stator teeth and the rotor 1 has 2 poles (i.e., 1 pair of magnetic poles).

[0036] This application aims to protect an axial flux PCB motor. Its technical solution uses multiple oblique channels 301 arranged along the circumference of the winding structure 3 and multiple oblique stator teeth 201 arranged along the circumference of the stator core 2 to form an oblique pole structure. This causes the spatial phase of the harmonic magnetic field of each layer of teeth to be misaligned and superimposed and canceled in the air gap, which greatly reduces the amplitude of tooth harmonics and effectively suppresses torque pulsation and periodic electromagnetic excitation. This is beneficial to reducing the mechanical vibration and operating noise of the motor, and can also improve the running stability and control accuracy of the motor.

[0037] It should be understood that the specific embodiments described above are merely illustrative or explanatory of the principles of this application and do not constitute a limitation thereof. Therefore, any modifications, equivalent substitutions, improvements, etc., made without departing from the spirit and scope of this application should be included within the protection scope of this application. Furthermore, the appended claims are intended to cover all variations and modifications falling within the scope and boundaries of the appended claims, or equivalent forms of such scope and boundaries.

Claims

1. An axial flux PCB motor, characterized in that, The device includes a rotor (1), a stator core (2), and a winding structure (3). The winding structure (3) forms a plurality of oblique channels (301) arranged along its circumference. The stator core (2) includes a plurality of oblique stator teeth (201) arranged along its circumference. The oblique stator teeth (201) are adapted to the oblique channels (301). Each oblique stator tooth (201) passes through the corresponding oblique channel (301) to magnetically couple with the rotor (1).

2. The axial flux PCB motor according to claim 1, characterized in that, The winding structure (3) includes multiple PCB winding layers (302) stacked along the axial direction of the stator core (2). Each PCB winding layer (302) has multiple mating holes (303) opened along its own circumference, and adjacent PCB winding layers (302) are staggered so that the mating holes (303) corresponding to each PCB winding layer (302) are staggered. Each of the oblique channels (301) is formed by stacking corresponding mating holes (303) on each of the PCB winding layers (302).

3. The axial flux PCB motor according to claim 2, characterized in that, All the inclined stator teeth (201) are inclined around the stator core (2), and all the inclined stator teeth (201) have the same inclination angle.

4. The axial flux PCB motor according to claim 3, characterized in that, The stator core (2) includes a first stator core (21) and a second stator core (22), and the winding structure (3) includes a first winding structure (31) and a second winding structure (32). The first stator core (21) and the second stator core (22) are located on both sides of the rotor (1), and the first winding structure (31) and the second winding structure (32) are located on both sides of the rotor (1). The first winding structure (31) is located between the first stator core (21) and the rotor (1), and the second winding structure (32) is located between the second stator core (22) and the rotor (1). Each of the oblique stator teeth (201) of the first stator core (21) passes through the corresponding oblique channel (301) on the first winding structure (31) and is magnetically coupled to one side of the rotor (1), and each of the oblique stator teeth (201) of the second stator core (22) passes through the corresponding oblique channel (301) on the second winding structure (32) and is magnetically coupled to the other side of the rotor (1).

5. The axial flux PCB motor according to claim 4, characterized in that, For the oblique stator teeth (201) on the first stator core (21) and the oblique stator teeth (201) on the second stator core (22) in the same axial direction, the oblique directions of the two are the same.

6. The axial flux PCB motor according to claim 4, characterized in that, The inclined stator teeth (201) on the first stator core (21) and the inclined stator teeth (201) on the second stator core (22) are in opposite directions along the same axis.

7. The axial flux PCB motor according to claim 4, characterized in that, The number of PCB winding layers (302) in the first winding structure (31) is the same as the number of PCB winding layers (302) in the second winding structure (32).

8. The axial flux PCB motor according to claim 7, characterized in that, The PCB winding layers (302) of the first winding structure (31) have the same structure as the PCB winding layers (302) of the second winding structure (32).

9. The axial flux PCB motor according to claim 8, characterized in that, Each of the PCB winding layers (302) is a fractional slot concentrated winding structure (3). The conductive lines of each of the PCB winding layers (302) are wound around the outer periphery of the corresponding mating hole (303), and each conductive line independently corresponds to one mating hole (303), so that the conductive line and the oblique stator tooth (201) passing through the corresponding mating hole (303) form a magnetic coupling circuit.

10. The axial flux PCB motor according to any one of claims 1-9, characterized in that, The rotor (1) includes a plurality of rotor blocks (11) arranged circumferentially, the number of rotor blocks (11) being less than the number of oblique stator teeth (201) of the stator core (2).

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