Miniature two-phase claw pole type motor based on LDS technology and fan thereof

Abstract

The invention discloses a miniature two-phase claw pole type motor based on an LDS technology and a fan thereof, the motor comprises an outer frame, a rotor unit and a stator unit, the stator unit comprises two stator assemblage, the two stator assemblage are coaxially arranged on the outer frame in a stacked mode and staggered by a certain mechanical angle in the circumferential direction, and the two stator assemblage are coaxially arranged on the outer frame in a staggered mode. The stator assembly is a claw pole type motor stator. The motor is reasonable in structural design, the scheme that the two stators are assembled to form a two-phase motor is ingeniously adopted, and the phase difference of torque waveforms is reasonably distributed, so that torque fluctuation is effectively reduced, and vibration and noise are reduced; meanwhile, the stator assemblage adopts a claw pole type motor stator structure, so that compared with an axial magnetic flux motor, the magnetic leakage phenomenon can be obviously reduced; in addition, the three-dimensional conducting circuit is manufactured on the outer frame through the LDS technology, electronic elements can be integrated on the surface of the outer frame, space is effectively saved, the size is reduced, the size is further reduced, and the overall structure of the fan can be more compact and ultra-thin.

Description

Technical Field

[0001] The present invention relates to the technical field of fans, and in particular to a micro two-phase claw-pole motor based on an LDS process and a fan thereof. Background Art

[0002] As smart terminals such as laptops, tablets, and mobile phones tend to be thinner and lighter, the fans used to dissipate heat in terminal products are also becoming thinner and thinner, and the requirements for the sound quality of micro fans are becoming more and more stringent. How to further improve the sound quality of micro fans has posed a great challenge to the fan industry.

[0003] According to research, the sound quality of the micro fan is not only related to the residual imbalance of the rotor, but also closely related to the vibration of the motor. From the source of vibration, the vibration source of the motor is divided into torque fluctuation and axial force fluctuation. Torque fluctuation is the main cause of vibration and noise in the motor. The torque fluctuation of the motor and its suppression technology have always been one of the research hotspots of brushless DC motors. Therefore, it is of great significance to study methods to reduce or suppress torque fluctuation.

[0004] For micro fans, due to limited space, the motor solutions currently used are relatively limited. The motor solutions for commercial micro fans are mainly the following:

[0005] 1. Radial flux motor. Due to limited size and space, a 4-slot 4-pole radial motor solution is generally used - Solution 1.

[0006] 2. Axial flux motor, also called disc motor. Due to the limited size and space, the ironless motor structure is often used. For the slot-pole matching of the stator and rotor, a 4-slot 4-pole single-phase motor - Scheme 2, or a 3-slot 4-pole three-phase motor - Scheme 3, or a 4-slot 6-pole two-phase motor - Scheme 4 is often used.

[0007] For Solution 1, this driving mode is a typical square wave voltage drive, which has fundamental torque fluctuations, and it is very difficult to suppress this torque fluctuation.

[0008] For solution 2, this driving mode is still a typical square wave voltage drive. In addition to the principle of torque fluctuation, this driving mode also has the problem of difficulty in starting. To solve this problem, a pre-eccentric positioning solution is often used, that is, a high magnetic permeability material is used to attract the rotor to a position that is easy to start. However, the introduction of high magnetic permeability materials will lead to additional problems. The presence of high magnetic permeability materials will produce additional cogging effects, causing cogging torque pulsation, which will further worsen the torque fluctuation.

[0009] For Solution 3, the motor with an odd number of slots (or an odd number of coils) in the stator naturally has unbalanced radial electromagnetic force, which will cause additional vibration and noise. Therefore, this solution is still not the best solution.

[0010] For scheme 4, the motor can be considered to be two 6-slot 6-pole single-phase disc motors connected in parallel. For each single-phase motor, due to space limitations, 2 coils are used to simulate the effect of 6 coils. In order to achieve the best torque fluctuation suppression effect and avoid causing unbalanced electromagnetic force, the two motors are staggered by 270° electrical angle. This scheme is the driving scheme for commercial 4-slot 6-pole motors. In theory, this scheme has a good torque fluctuation suppression effect. However, due to the unevenness of the magnetic field waveform, the torque fluctuation generated by replacing 6 coils with 2 coils is still relatively large. After the two phases are superimposed, the torque fluctuation suppression effect will be weakened to a considerable extent.

[0011] In addition, schemes 2, 3, and 4 also have a common disadvantage - magnetic leakage. Specifically, for the disc motor scheme, its magnets are often made of sintered NdFeB, which has a high magnetic energy product. In addition, the air gap flux itself is mainly distributed along the axial direction during operation (this feature is the origin of the name of the axial magnet motor). Therefore, when the fan frame is made of a plastic frame, there is a more obvious magnetic leakage phenomenon, which may cause electromagnetic interference to the equipment using this fan.

[0012] Therefore, none of the above solutions are the best. In addition, for ultra-thin fans, the space that can be reduced in the axial dimension is extremely limited. Multiple fans are connected using FPC solutions. However, FPC itself is flexible and generally requires a reinforcement plate, which results in a limited reduction in the axial dimension of the fan solution using FPC. Secondly, the FPC is generally fixed to the fan frame using adhesive, which has limited strength.

[0013] To this end, it is necessary to develop a micro two-phase claw-pole motor and fan based on LDS technology that meets the requirements of ultra-thinness, low torque fluctuation, and low leakage flux. Summary of the invention

[0014] In view of the above-mentioned deficiencies, the object of the present invention is to provide a micro two-phase claw-pole motor based on LDS technology which has a reasonable structural design and meets the requirements of ultra-thinness, low torque fluctuation and low leakage flux.

[0015] To achieve the above purpose, the technical solution provided by the present invention is:

[0016] A micro two-phase claw-pole motor based on LDS technology includes an outer frame, a rotor unit and a stator unit. The stator unit includes two stator assemblies. The two stator assemblies are coaxially stacked on the outer frame and staggered at a certain mechanical angle along the circumferential position. The stator assembly is a claw-pole motor stator. A three-dimensional conductive circuit is formed on the surface of the outer frame by the LDS process. Electronic components are welded on the three-dimensional conductive circuit. Both stator assemblies are connected to the three-dimensional conductive circuit. The rotor unit is rotatably arranged on the outer frame and is compatible with the two stator assemblies. Two stator assemblies are used to form a two-phase motor solution. The torque fluctuation is reduced by reasonably allocating the phase difference of the torque waveform. The stator assembly adopts a claw-pole motor stator structure instead of an axial flux motor to reduce magnetic leakage.

[0017] As a preferred solution of the present invention, the rotor unit is a rotor assembly, which includes a motor housing and an annular magnet disposed on the inner wall of the motor housing. The uniformity of the magnetic field waveform of the annular magnet is significantly improved compared with the magnetic field of the axial magnetic disk.

[0018] As a preferred embodiment of the present invention, the two stator assemblies are claw-pole motor stators with an eight-slot eight-pole structure, and the two stator assemblies are staggered along the circumferential position by the following theoretical mechanical angles: 22.5°, 67.5°, 112.5 or 157.5°.

[0019] As a preferred solution of the present invention, the two stator assemblies are claw-pole motor stators with a six-slot six-pole structure, and the two stator assemblies are staggered along the circumferential position by the following theoretical mechanical angles: 30°, 90°, and 150°.

[0020] As a preferred solution of the present invention, the two stator assemblies are claw-pole motor stators with a four-slot four-pole structure, and the two stator assemblies are staggered along the circumferential position by the following theoretical mechanical angles: 45° and 135°.

[0021] As a preferred solution of the present invention, the surface of the outer frame has recesses for accommodating the electronic components, which can fully utilize the thickness of the outer frame, reduce the occupied space, ensure the flatness of the surface, improve the smoothness of the flow channel, and reduce the noise of the fan.

[0022] As a preferred solution of the present invention, the electronic components include two ICs, and the staggered angle of the two ICs is any one of the theoretical mechanical angles of the staggered positions of the two stator assemblies along the circumferential direction. Both ICs are integrated with Hall effect sensors, which can sense the position of the rotor magnet to control the timely phase change of the two stator assemblies to ensure that the coordination of the two stator assemblies achieves the best effect.

[0023] As a preferred solution of the present invention, the three-dimensional conductive circuit is located on the upper surface and / or lower surface of the outer frame, and the outer frame is provided with a gold finger connected to the three-dimensional conductive circuit, which reduces the occupied space and can provide reliable electrical connection and signal transmission.

[0024] As a preferred solution of the present invention, the outer frame comprises a top plate, a bottom plate and side walls arranged at the edge of the bottom plate, and the top plate is arranged on the side walls. The structure is reasonably designed and easy to assemble and produce.

[0025] A micro fan comprises blades and the micro two-phase claw-pole motor based on the LDS process, wherein the blade cover is arranged on the rotor unit of the micro two-phase claw-pole motor based on the LDS process.

[0026] The beneficial effects of the present invention are as follows: the present invention has a reasonable structural design, and cleverly adopts two stator assemblies to form a two-phase motor solution. By reasonably allocating the phase difference of the torque waveform, the torque fluctuation is effectively reduced, and the vibration and noise are reduced; at the same time, the stator assembly adopts a claw-pole motor stator structure, which can significantly reduce the leakage magnetic phenomenon and reduce the electromagnetic interference to peripheral equipment compared with the axial flux motor; in addition, the LDS process is used to make a three-dimensional conductive circuit on the outer frame, and electronic components can be integrated on the surface of the outer frame, which effectively saves space, reduces the volume, and further reduces the size, so that the overall structure of the fan can be more compact and ultra-thin.

[0027] The present invention is further described below in conjunction with the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a three-dimensional structural schematic diagram of the present invention.

[0029] Figure 2 It is a cross-sectional structural schematic diagram of the present invention.

[0030] Figure 3 It is a schematic diagram of the decomposition structure of the present invention.

[0031] Figure 4 It is a structural schematic diagram of the stator unit in the present invention.

[0032] Figure 5 It is a harmonic component diagram of the present invention.

[0033] Figure 6 It is the torque fluctuation diagram of the present invention.

[0034] Figure 7 It is the phase voltage waveform diagram of the present invention. DETAILED DESCRIPTION

[0035] For example, see Figures 1 to 7, a micro fan provided in this embodiment includes a fan blade 1 and a micro two-phase claw-pole motor based on the LDS process, wherein the micro two-phase claw-pole motor based on the LDS process includes an outer frame 2, a rotor unit and a stator unit 5. The rotor unit is a rotor assembly, and the rotor assembly includes a motor housing 3 and an annular magnet 4 arranged on the inner wall of the motor housing 3. The fan blade 1 is covered on the motor housing 3 of the micro two-phase claw-pole motor based on the LDS process. The outer frame 2 includes a top plate 21, a bottom plate 22 and a side wall 23 arranged on the edge of the bottom plate 22, and the top plate 21 is arranged on the side wall 23. A magnetic conductive middle tube 24 is provided on the bottom plate 22, and a bearing 26 is provided in the magnetic conductive middle tube 24, and a shaft core 25 compatible with the bearing 26 is provided on the motor housing 3. The bearing 26 is installed in the shaft core 25, so that the motor housing 3 is assembled on the magnetic conductive middle tube 24.

[0036] The stator unit 5 includes two stator assemblies 51, which are coaxially stacked and sleeved on the magnetic conductive middle tube 24, and are staggered at a certain mechanical angle along the circumferential position. The stator assembly 51 is a claw-pole motor stator. The rotor unit is a rotor assembly, that is, the two stator assemblies 51 share a rotor assembly, and the uniformity of the magnetic field waveform of the annular magnet 4 is significantly improved relative to the magnetic field of the axial magnetic disk. Each stator assembly 51 includes an upper claw pole 511, a coil 512 and a lower claw pole 513. The following is an example of two stator assemblies 51 staggered at a certain mechanical angle (based on an angle of <180°) along the circumferential position. The preferred mechanical angle scheme is as follows:

[0037] Solution 1: The two stator assemblies 51 can both be claw-pole motor stators with an eight-slot eight-pole structure, forming a two-phase motor. The two stator assemblies 51 are staggered along the circumferential position by the following four theoretical mechanical angles (with an angle of <180° as the standard): 22.5°, 67.5°, 112.5 or 157.5°. Considering the assembly error, the 157.5°*(1±10%) solution is preferred.

[0038] Solution 2: Both of the two stator assemblies 51 are claw-pole motor stators with a six-slot six-pole structure, forming a two-phase motor. The two stator assemblies 51 are staggered along the circumferential position by the following three theoretical mechanical angles (with an angle of <180° as the standard): 30°, 90°, and 150°. Considering the assembly error, the 90°*(1±10%) solution is preferred.

[0039] Solution 3: Both of the two stator assemblies 51 are claw-pole motor stators with a four-slot four-pole structure, forming a two-phase motor. The two stator assemblies 51 are staggered along the circumferential position by the following two theoretical mechanical angles (with an angle of <180° as the standard): 45° and 135°. Considering the assembly error, the 135°*(1±10%) solution is preferred.

[0040] A three-dimensional conductive circuit 6 is formed on the surface of the outer frame 2 by the LDS process, and an electronic component 7 is welded on the three-dimensional conductive circuit 6. Both stator assemblies 51 are connected to the three-dimensional conductive circuit 6. The electronic component 7 includes two ICs, capacitors and other related electronic components 7, wherein the staggered angle of the two ICs can take any one of the theoretical mechanical angles of the two stator assemblies 51 staggered along the circumferential position. Both ICs are integrated with Hall effect sensors, which can sense the position of the rotor magnet to control the timely phase change of the two stator assemblies to ensure that the cooperation of the two stator assemblies achieves the best effect. Preferably, there is a recessed position on the surface of the outer frame 2 for accommodating the electronic component 7. The thickness space of the outer frame 2 can be fully utilized to reduce the occupied space, and the flatness of the surface can also be ensured, the smoothness of the flow channel can be improved, and the noise of the fan can be reduced. For the convenience of connection, the three-dimensional conductive circuit 6 is located on the upper surface and / or lower surface of the outer frame 2, and the outer frame 2 is provided with a gold finger 8 connected to the three-dimensional conductive circuit 6, which reduces the occupied space and can provide reliable electrical connection and signal transmission.

[0041] In summary, the present invention has the following advantages:

[0042] 1. Reduced torque fluctuation. First, two stators are cleverly assembled 51 to form a two-phase motor solution. Take solution 2 as an example. Figure 7 As shown, the phase difference between the two motors is clearly shown, indicating that the two motors work alternately. By reasonably allocating the phase difference of the torque waveform of the two stator assemblies 51, the torque fluctuation is reduced by more than 80%. The torque fluctuation is effectively reduced, and the vibration and noise are reduced; secondly, each stator assembly 51 of the motor can independently constitute a complete motor, and the number of stator tooth poles is the same as the number of rotor poles, so the torque waveform caused by the uneven magnetic field is effectively improved. Compared with the conventional design, the high-order harmonic component of the new design is reduced by about 76%.

[0043] 2. Reduced magnetic flux leakage. Since the stator assembly 51 adopts a claw-pole motor stator structure, its air gap magnetic circuit is similar to that of a conventional radial motor, so its magnetic flux leakage is very weak and can be basically ignored. In addition, the rotor assembly adopts an annular magnet, and the uniformity of its magnetic field waveform is significantly improved compared to the magnetic field of the axial magnetic disk.

[0044] 3. By adopting the claw-pole motor, the number of coils of the motor is effectively reduced, thereby reducing the manufacturing cost.

[0045] According to the disclosure and teaching of the above specification, technicians in the field to which the present invention belongs can also change and modify the above implementation. Therefore, the present invention is not limited to the specific implementations disclosed and described above, and some modifications and changes to the present invention should also fall within the protection scope of the claims of the present invention. In addition, although some specific terms are used in this specification, these terms are only for the convenience of explanation and do not constitute any limitation to the present invention. As described in the above embodiments of the present invention, other motor and fan structures obtained by using the same or similar structures are all within the protection scope of the present invention.

Claims

1. A micro two-phase claw-pole motor based on LDS technology, comprising an outer frame, a rotor unit and a stator unit, characterized in that: The stator unit includes two stator assemblies, which are coaxially stacked on the outer frame and staggered at a certain mechanical angle along the circumferential position. The stator assembly is a claw-pole motor stator; a three-dimensional conductive circuit is formed on the surface of the outer frame through the LDS process, and electronic components are welded on the three-dimensional conductive circuit. The two stator assemblies are connected to the three-dimensional conductive circuit. The rotor unit is rotatably arranged on the outer frame and is compatible with the two stator assemblies.

2. The micro two-phase claw-pole motor based on LDS technology according to claim 1 is characterized in that: The rotor unit is a rotor assembly, which includes a motor housing and an annular magnet arranged on the inner wall of the motor housing.

3. The micro two-phase claw-pole motor based on LDS technology according to claim 1 is characterized in that: The two stator assemblies are both claw-pole motor stators with an eight-slot eight-pole structure, and the two stator assemblies are staggered along the circumferential position by the following theoretical mechanical angles: 22.5°, 67.5°, 112.5° or 157.5°.

4. The micro two-phase claw-pole motor based on LDS technology according to claim 1 is characterized in that: The two stator assemblies are both claw-pole motor stators with a six-slot six-pole structure, and the two stator assemblies are staggered along the circumferential position by the following theoretical mechanical angles: 30°, 90°, and 150°.

5. The micro two-phase claw-pole motor based on LDS technology according to claim 1 is characterized in that: The two stator assemblies are both claw-pole motor stators with a four-slot four-pole structure, and the two stator assemblies are staggered along the circumferential position by the following theoretical mechanical angles: 45° and 135°.

6. The micro two-phase claw-pole motor based on LDS technology according to claim 1 is characterized in that: The surface of the outer frame is provided with recessed positions for accommodating the electronic components.

7. The micro two-phase claw-pole motor based on LDS technology according to any one of claims 3 to 5, characterized in that: The electronic component comprises two ICs, and the staggered angle of the two ICs is any one of the theoretical mechanical angles of the stator assemblies staggered along the circumferential direction.

8. The micro two-phase claw-pole motor based on LDS technology according to claim 1 is characterized in that: The three-dimensional conductive circuit is located on the upper surface and / or the lower surface of the outer frame, and the outer frame is provided with a gold finger connected to the three-dimensional conductive circuit.

9. The micro two-phase claw-pole motor based on LDS technology according to claim 1 is characterized in that: The outer frame comprises a top plate, a bottom plate and side walls arranged at the edge of the bottom plate, and the top plate is arranged on the side walls.

10. A miniature fan, characterized in that: It comprises a fan blade and a micro two-phase claw-pole motor based on the LDS process as claimed in any one of claims 1 to 9, wherein the fan blade cover is arranged on a rotor unit of the micro two-phase claw-pole motor based on the LDS process.

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