Single-phase axial magnetic circuit brushless DC motor stator and actuator

Abstract

Disclosed is a single-phase axial magnetic circuit brushless DC motor stator, comprising two fan columns, a core, a stator base and a single coil, wherein the fan columns and the core each have an expanded fan-shaped crown at one end and a body with a reduced cross section relative to the crown at the other end, the single coil is held on the body of the core, and the stator base is combined with the bodies of the two fan columns and the core to form a closed magnetic circuit; the two fan columns are arranged on both sides of the core; the crown of each fan column and the crown of the core are respectively combined as constituent parts of a circle to form a substantially circular shape. A corresponding actuator is also disclosed. According to certain embodiments of the present application, the winding process is greatly simplified, the slot fill factor is increased, the efficiency is improved, the cost is reduced, etc.

Description

Technical Field

[0001] This invention relates to a stator and actuator for a single-phase axial magnetic circuit brushless DC motor, belonging to the field of brushless DC motors, and particularly to a single-winding axial magnetic circuit stator structure and an actuator having the corresponding structure. Background Technology

[0002] In a typical axial magnetic circuit motor, the stator and rotor have opposite circular surfaces. The stator usually includes an iron core, coil windings wound around the iron core, and a base for closing the magnetic circuit of the iron core. The rotor usually also includes discs for closing the magnetic circuit and structures for positioning and rotating relative to the stator, such as a shaft. The stator structure typically contains 2N iron cores, where N is at least 1. Each iron core usually has 2N windings formed by winding wires after mounting a bobbin. Adjacent windings have opposite winding directions, and the last 2N windings are connected end to end to form a single-phase structure. For a four-phase structure with N=2, there are 4 windings. To ensure product reliability, such windings usually need to be continuously wound. At the same time, to make full use of space and increase slot fill factor, the gap between each winding should be as small as possible. This process is very challenging, difficult, and costly. Summary of the Invention

[0003] The purpose of this invention, based on the above background, is to propose a stator and actuator for a single-phase axial magnetic circuit brushless DC motor. The stator comprises: two fan columns; a core; a stator base; and a single coil. Each fan column and the core has an extended fan-shaped crown at one end and a body with a reduced cross-section relative to the crown at the other end. The single coil is held on the core. The stator base, the bodies of the two fan columns, and the core body are joined to form a closed magnetic circuit. The fan columns are arranged on both sides of the core. The crowns of the two fan columns and the crown of the core are each part of a circle.

[0004] According to an alternative embodiment, the two fan column crowns and the one core crown are assembled into a generally circular shape; the outer side of the core and the inner side of the fan column are radially recessed relative to their crowns.

[0005] According to an alternative embodiment, the stator of the single-phase axial magnetic circuit brushless DC motor further includes a frame, the core body is fitted inside the frame, and the single coil is wound on the frame.

[0006] According to an alternative embodiment, the stator base is configured such that the two sector columns and the one core are in contact with the plane of the stator base on the bottom surface of their respective bodies.

[0007] According to an alternative embodiment, the iron core, the sector column, and the stator base are made of soft magnetic material.

[0008] According to an optional embodiment, the stator of the single-phase axial magnetic circuit brushless DC motor is overmolded into an integral structure; the overmolding of the stator simultaneously forms multiple stator flange protrusions for fixing with corresponding assembly interfaces.

[0009] According to an alternative embodiment, a bushing for receiving the mover shaft is embedded in the center of the stator of the single-phase axial magnetic circuit brushless DC motor.

[0010] A single-phase axial magnetic circuit brushless DC actuator includes the stator of a single-phase axial magnetic circuit brushless DC motor. It also includes a rotor, a thrust bearing, and a cover. The rotor comprises a shaft, rotor discs, magnets, and a transmitter. The shaft is coaxially fixed to the rotor discs. An annular magnet is fixed to the side of the rotor discs opposite to the stator. The transmitter is coaxially positioned with the shaft and fixed to the side of the rotor discs opposite to the stator. After the rotor is fitted with the thrust bearing, it is inserted into the central through-hole of the stator for positioning. The cover is connected to the stator and is used to close the stator opening where the rotor is inserted. A receiver is arranged inside the cover. The detection center of the receiver is arranged on the coaxial line of the rotor shaft and spaced a certain distance from the transmitter, used to detect the angular signal of the rotor's rotation relative to the stator.

[0011] The beneficial effects of this invention are as follows: The actuator stator structure, through a special design of the iron core, sector column, coil, frame, and stator base, achieves a magnetic field effect of four adjacent iron core crowns alternating N / S poles using a single coil winding, eliminating the need for an independent coil winding for each pole. Instead, a series of four coil windings are combined to form an N / S alternating four-pole stator structure. This greatly simplifies the coil winding process and improves efficiency. Furthermore, since there is no need to consider the gap between the four windings and sacrifice actual winding space, the slot fill factor can be increased, improving the space utilization of the actuator.

[0012] The actuator's stator is integrally molded, which not only securely positions all stator components but also allows the covering material to fill the coil gaps during the molding process. This effectively and quickly conducts the coil's heat through the core and covering material to the outside for heat dissipation. Improved heat dissipation not only enhances the actuator's performance but also improves its reliability, especially in high-temperature applications.

[0013] The actuator stator of this invention uses fewer components and a simpler and more reliable assembly process, making it easier to achieve large-scale stable industrialization. It also greatly reduces the cost of product components and assembly processes, making it extremely valuable for mass applications. Attached Figure Description

[0014] Figure 1This is an isometric view of the actuator according to an embodiment of the present invention.

[0015] Figure 2 This is a front view of the actuator according to an embodiment of the present invention.

[0016] Figure 3 This is a left view of the actuator in an embodiment of the present invention.

[0017] Figure 4 The actuator of the embodiment of the present invention Figure 2 The cross-sectional view of AA in the diagram.

[0018] Figure 5 The actuator of the embodiment of the present invention Figure 3 A cross-sectional view of BB in the diagram.

[0019] Figure 6 This is an isometric view of the actuator stator of an embodiment of the present invention (for clarity, only the sector column, core, coil, and stator base are shown).

[0020] Figure 7 This is a front view of the stator structure of an actuator in the prior art (for clarity, only the sector column, core, coil, and stator base are retained).

[0021] Figure 8 It is the stator section structure of the actuator in the prior art Figure 7 A cross-sectional view of CC in the diagram.

[0022] List of reference numerals in the attached diagram: 1-Stator, 112-Sector column, 1121-Sector column crown, 1122-Sector column body, 113-Core, 1131-Core crown, 1132-Core body, 122-Frame, 132-Coil, 142-Stator base, 1421-Flange protrusion structure of stator base, 15-Covering material, 16-Flange protrusion structure of stator, 17-Bushing, 18-Claw, 19-Glue groove, 21-Shaft, 22-Rotor disc, 23-Magnet, 24-Transmitter, 3-Cover, 31-Connector, 32-Snap-on, 33-PCB positioning post, 4-PCB, 41-Receiver, 5-Bearing. Detailed Implementation

[0023] To provide a detailed explanation of the stator of the single-phase axial magnetic circuit brushless DC motor of the present invention and to facilitate better understanding, the stator of the actuator and the overall actuator implementation method of the present invention will first be described. Figure 1 , Figure 2 , Figure 3 These are, respectively, the isometric view, the front view, and the left view of the actuator according to an embodiment of the present invention. Figure 4 , Figure 5These are the actuator edges of embodiments of the present invention. Figure 2 The cross-sectional view of AA and along Figure 3 The cross-sectional view of BB in the figure is shown. Its specific implementation is as follows: The actuator includes a stator 1, a rotor (not labeled in the figure), a cover 3, a PCB 4, and a bearing 5. The stator 1 includes an iron core 113 and a pair of sector columns 112 (see [reference needed]). Figure 8 The rotor includes a frame 122, a coil 132, a stator base 142, a bushing 17, and a covering material 15; the rotor includes a shaft 21, a rotor disc 22, a magnet 23, and a transmitter 24.

[0024] The iron core 113 has a crown 1131 and a body 1132, the crown 1131 being opposite to the magnet 23 of the rotor. A frame 122 is fitted around the body 1132 of the iron core 113, and the coil 132 is arranged within the frame 122. The aforementioned components of the stator (and possibly other components) are further integrally covered by a covering material 15, and the covering process simultaneously embeds the bushing 17 into the center of the stator 1, making it part of the stator as a whole. The covering can be injection molding, epoxy potting, or any similar process. After covering, the stator 1 simultaneously forms several flange protrusions 16 for connecting the actuator to the mounting structure to which the actuator is to be installed, with at least two flange protrusions 16; the stator 1 also forms several claws 18 for connecting with the latches 32 of the cover 3. Of course, for those skilled in the art, the stator 1 and the cover 3 can be connected in many other ways, such as bolting, gluing, laser welding, or any structural design and process that achieves a close fit.

[0025] The shaft 21 is coaxially and fixedly connected to the rotor disc 22. The magnet 23 is coaxially and fixedly connected to one side of the rotor disc 22. The transmitter 24 is coaxially fixed to the shaft 21 and located on the other side of the rotor disc 22. Preferably, the transmitter 24 can be fitted and fixed to the rotor disc 22. The transmitter 24 can be cylindrical or annular. In the rotor arrangement described above, after the bearing 5 is fitted on one side of the magnet 23, it is inserted into the inner hole of the bushing 17 of the stator 1, opposite to the fan column and the core crown.

[0026] The cover 3 is fastened to one end of the stator 1 by a snap fastener 32, which engages with the stator 1's claw 18. A sealing ring or adhesive is arranged in the glue groove 19 to achieve a sealed connection between the cover 3 and the stator 1. A PCB 4 is also arranged inside the cover 3, and a receiver 41 is arranged on the PCB. The receiver 41 is typically a Hall effect sensor used to detect and calculate the angle of the rotor relative to the stator 1. The receiver 41 is positioned on the side opposite to the transmitter 24 and maintains a certain distance. The detection center of the receiver 41 is located on the symmetrical central axis of the transmitter 24, i.e., coaxial with axis 21. The receiver 41 calculates the angle of the rotor relative to the stator 1 by detecting two perpendicular components in a plane parallel to the plane of the transmitter 24 emitted from the detection point of the receiver 41.

[0027] The following will further describe the implementation of the stator core structure of the single-phase axial magnetic circuit brushless DC motor of the present invention. Figure 6 , Figure 7 , Figure 8 These are, respectively, isometric views, front views, and along the axis of the actuator stator of the embodiment of the present invention, which retain only the sector column, iron core, coil, and stator base. Figure 7 The cross-sectional view of CC is shown. The fan column 112 is arranged on both sides of the iron core 113. The coil 132 is arranged around the outer periphery of the body portion of the iron core 113 and passes between the iron core 113 and the fan column 112. For ease of explanation, the skeleton is not shown in the figure. The iron core 113 has a through hole in the center for accommodating the bushing 17. The bottom surface of the body of the iron core 113 and the fan column 112 is completely in contact with the plane of one side of the stator base 142. The stator base 142 has four flange protrusions 1421, which will serve as embedded parts for the flange protrusion structure 16 of the stator during the stator encapsulation process.

[0028] The beneficial effects of this invention are as follows: The actuator stator structure, through a special design of the iron core, sector column, coil, frame, and stator base, achieves a magnetic field effect of four adjacent iron core crowns alternating N / S poles using a single coil winding, eliminating the need for an independent coil winding for each pole. Instead, a series of four coil windings are combined to form an N / S alternating four-pole stator structure. This greatly simplifies the coil winding process and improves efficiency. Furthermore, since there is no need to consider the gap between the four windings and sacrifice actual winding space, the slot fill factor can be increased, improving the space utilization of the actuator.

[0029] The actuator's stator is integrally molded, which not only securely positions all stator components but also allows the covering material to fill the coil gaps during the molding process. This effectively and quickly conducts the coil's heat through the core and covering material to the outside for heat dissipation. Improved heat dissipation not only enhances the actuator's performance but also improves its reliability, especially in high-temperature applications.

[0030] The actuator stator of this invention uses fewer components and a simpler and more reliable assembly process, making it easier to achieve large-scale stable industrialization. It also greatly reduces the cost of product components and assembly processes, making it extremely valuable for mass applications.

[0031] The above description is merely a preferred embodiment of the present invention. The single-phase axial magnetic circuit brushless DC motor stator and actuator of the present invention are not limited to the above-described embodiments, nor do they limit the patent scope of the present invention. Any structural modifications made based on the above inventive concept and the description and drawings of the present invention, whether directly or indirectly applied to other technical fields, are included within the patent protection scope of the present invention.

Claims

1. A stator for a single-phase axial magnetic circuit brushless DC motor, characterized in that, The stator of the single-phase axial magnetic circuit brushless DC motor includes: two fan columns, one iron core, one frame, a stator base, and a single coil. Each fan column and the iron core has an extended fan-shaped crown at one end and a body with a reduced cross-section relative to the crown at the other end. The iron core body is fitted inside the frame, and the single coil is wound around the frame. The stator base, the bodies of the two fan columns, and the iron core body are joined together to form a closed magnetic circuit. The two fan columns are arranged on both sides of the iron core. The fan column crown and the iron core crown are each part of a circle, joined together to form an approximately circular shape.

2. The stator of a single-phase axial magnetic circuit brushless DC motor according to claim 1, characterized in that, The stator base is configured such that the bottom surfaces of the corresponding bodies of the two sector columns and the one core are in contact with the plane of the stator base.

3. The stator of a single-phase axial magnetic circuit brushless DC motor according to claim 1 or 2, characterized in that, The iron core, the sector column, and the stator base are made of soft magnetic material.

4. The stator of a single-phase axial magnetic circuit brushless DC motor according to claim 1 or 2, characterized in that, The stator of the single-phase axial magnetic circuit brushless DC motor is encapsulated and molded into an integral structure.

5. The stator of a single-phase axial magnetic circuit brushless DC motor according to claim 4, characterized in that, The stator overmolding process simultaneously forms multiple stator flange protrusions for fixing to the corresponding assembly interfaces.

6. The stator of a single-phase axial magnetic circuit brushless DC motor according to claim 4, characterized in that, The single-phase axial magnetic circuit brushless DC motor has a bushing at the center of the stator, which is embedded to receive the shaft of the mover.

7. An actuator, characterized in that, The actuator includes a single-phase axial magnetic circuit brushless DC motor stator according to any one of claims 1-6.

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