Split heat expansion prevention motor for robot

Abstract

This invention relates to the field of robot component technology, and particularly to a split-type thermal expansion-resistant motor for robots. It includes a stator base, with a concentric annular stator mounting ring at the center of the stator base. Several winding modules are arranged in a circular array on the outer wall of the stator mounting ring. Each winding module includes a back plate, with isolation teeth on the side of the back plate away from the central axis of the stator mounting ring. A set of winding stiffeners is horizontally arranged at both the upper and lower edges of the back plate. This invention allows for bidirectional heat exchange between the winding body, making the heat exchange more three-dimensional. Simultaneously, the heat dissipation inlet and outlet are funnel-shaped structures, allowing cold air to enter quickly and hot air to exit rapidly, thereby improving heat exchange efficiency. This solves the problem of thermal expansion caused by poor heat dissipation in traditional motors.

Description

Technical Field

[0001] This invention belongs to the field of robot component technology, and specifically relates to a split-type thermal expansion-resistant motor for robots. Background Technology

[0002] In current technology, due to the increasingly precise control of robots, brushless motors are widely used to minimize malfunctions in moving parts during operation. Brushless motors are typically designed as separate units, meaning the motor itself and the electronic controller are separate for unified control.

[0003] A search revealed that the cited publication number is CN120834682A, published on October 24, 2025, entitled "A Brushless Motor for an Underwater Robot," comprising a housing; the housing has a front end and a rear end, the rear end of the housing being open, and a cover plate that can be inserted and fixed to the rear end of the housing; a stator sleeve is concentrically arranged inside the housing, extending along the extension direction of the housing, forming a stator mounting space between the stator sleeve and the housing, and a stator assembly is fitted within the stator mounting space; one end of the stator sleeve is integrally injection molded with the front end of the housing, and the other end of the stator sleeve extends toward the cover plate. The stator bushing has a rotating rotor assembly inside. The rotor assembly includes a rotating shaft and a rotor assembly fixedly mounted in the middle of the rotating shaft. A first bearing is fixedly mounted on the front end of the housing, and a second bearing is fixedly mounted on the cover plate. The front end of the housing has a through hole for the rotating shaft to pass through. One end of the rotating shaft is fixedly connected to the second bearing, and the other end of the rotating shaft is fixedly connected to the first bearing and extends out of the through hole. The rotating shaft is rotatably mounted inside the stator bushing through the first and second bearings. An air gap is formed between the rotor assembly and the stator bushing. The cover plate has multiple connecting parts that connect the inner wall of the housing to the outside. The connecting parts are set corresponding to the second bearing.

[0004] However, the above embodiments still have the following drawbacks:

[0005] The above embodiments can only dissipate heat in one direction from the outside of the winding, and cannot perform bidirectional heat exchange from the inside. After long-term continuous operation, the motor will still experience thermal expansion due to poor heat dissipation. Summary of the Invention

[0006] To address the above problems, the present invention provides a split-type thermal expansion-resistant motor for robots, including a stator base, wherein a stator mounting ring with a circular structure is concentrically arranged at the center of the stator base, and several sets of winding modules are distributed in a circular array on the outer wall of the stator mounting ring.

[0007] The winding module includes a back plate, on the side of the back plate away from the central axis of the stator mounting ring, an isolation tooth is provided, and a set of winding ribs are horizontally provided at both the upper and lower edges of the back plate, with the other ends of the two sets of winding ribs mounted on the isolation tooth; an internal cooling mechanism is provided between the two sets of winding ribs, and the outer shell of the internal cooling mechanism is made of insulating material;

[0008] The internal cooling mechanism is a three-dimensional tubular structure, including several sets of horizontal pipes arranged horizontally, with the sets of horizontal pipes arranged at equal intervals along the vertical direction; a set of U-shaped pipes connects each adjacent set of horizontal pipes, and a set of intermediate pipes connects each set of U-shaped pipes at the same height.

[0009] Furthermore, a first bearing seat is fixedly installed at the top periphery of the stator base, and the central axis of the first bearing seat coincides with the central axis of the stator base; an outer rotor ring with a circular structure is rotatably connected to the first bearing seat, and an outer rotor head with a trumpet-shaped structure is fixedly installed on the top of the outer rotor ring, and several sets of heat dissipation air inlets are distributed in a circular array on the side walls of the outer rotor head.

[0010] Furthermore, an air intake funnel is movably installed at one end of the heat dissipation air intake hole near the inner cavity of the outer rotor head. The bottom of the air intake funnel extends obliquely towards the central axis of the outer rotor head. The air intake funnel has a trumpet-shaped structure and the entire air intake funnel has a mesh-like structure.

[0011] Furthermore, the inner wall of the outer rotor ring has several groups of neodymium magnets arranged in a ring array, the number of neodymium magnets is even, and the magnetic poles of two adjacent groups of neodymium magnets are set oppositely; the number of winding modules is less than the number of neodymium magnets; the winding modules are electromagnetically connected to the neodymium magnets.

[0012] Furthermore, an electronic speed controller is provided on one side of the stator base, and each winding module is electrically connected to the electronic speed controller.

[0013] Furthermore, the stator base has several sets of heat dissipation vents arranged in a ring array at its bottom, and the inner diameter of the top of the heat dissipation vent is larger than the inner diameter of its bottom; the inner wall of the heat dissipation vent is provided with a threaded vortex groove, and the threaded vortex groove has a spiral structure.

[0014] Furthermore, a Hall sensor is fixedly installed on the stator base, and the Hall sensor is electromagnetically connected to each group of neodymium magnets.

[0015] Furthermore, an electronic speed controller is provided on one side of the stator base, and the winding module also includes a winding body, with both ends of the winding body wound around two sets of winding backbones respectively.

[0016] The winding directions of two adjacent sets of winding bodies are opposite, and they are connected in pairs to form a winding mechanism. Each set of windings is connected to the opposite set of windings to form a working unit. The working unit is electrically connected to the electronic speed controller through a set of wires.

[0017] Furthermore, an inner rotor portion is rotatably connected to the central axis of the stator mounting ring. The bottom of the inner rotor portion is rotatably connected to the stator base, and the top extends directly above the outer rotor head. The inner rotor portion is fixedly connected to the outer rotor head.

[0018] Furthermore, the inner rotor section includes a snap-fit ​​part, which is rotatably connected to the stator base. A snap-fit ​​head is movably installed at the top center of the snap-fit ​​part. A rotating shaft is fixedly installed at the top center of the snap-fit ​​head. The rotating shaft is fixedly connected to the outer rotor head. The top of the rotating shaft extends to directly above the outer rotor head, and an annular top groove is concentrically provided at the top port. Several sets of side through grooves are distributed in an annular array around the top edge of the rotating shaft. The top of the side through grooves has an open structure, and the side through grooves communicate with the annular top grooves.

[0019] The beneficial effects of this invention are:

[0020] 1. The traditional one-piece winding frame is replaced with two symmetrical sets of winding rods, and an internal cooling mechanism is installed between the two sets of winding rods. During operation, external coolant storage components supply coolant to each set of horizontal tubes, U-shaped tubes, and intermediate tubes, facilitating heat exchange within the winding body. Simultaneously, external cool air is introduced through the heat dissipation inlet and exhausted through the heat dissipation outlet, further cooling the winding modules from the outside. This makes the heat exchange more comprehensive. Furthermore, the heat dissipation inlet and outlet are funnel-shaped, allowing cool air to enter quickly and hot air to exit rapidly, thus improving heat exchange efficiency. This solves the problem of thermal expansion caused by poor heat dissipation in traditional motors.

[0021] 2. The heat dissipation vent has a trumpet-shaped structure, with a larger inner diameter on the side closer to the inner cavity of the outer rotor ring. This causes the hot air to gradually accelerate as it is discharged. Due to the influence of the threaded vortex groove, the hot air forms a vortex while accelerating and is discharged in a concentrated manner, which facilitates heat energy collection and the treatment of hot air.

[0022] 3. An annular top groove is provided at the top end of the shaft, and multiple sets of side through grooves are distributed in a circular array around it. This allows the workpiece to be fixed on the shaft from multiple directions, including inside, outside, and sides. Even if the workpiece slips or shifts due to aging and wear caused by the high-speed rotation of the shaft. Compared with the traditional design where only one direction is set as a plane, this improves the service life and wear resistance of the shaft.

[0023] Other features and advantages of the invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention. The objects and other advantages of the invention may be realized and obtained by means of the structures pointed out in the description, claims and drawings. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0025] Figure 1 A schematic diagram of the structure of a motor according to an embodiment of the present invention is shown.

[0026] Figure 2 A schematic diagram showing the separation of the stator base and the outer rotor ring according to an embodiment of the present invention is shown.

[0027] Figure 3 A cross-sectional schematic diagram of the outer rotor head according to an embodiment of the present invention is shown.

[0028] Figure 4 A bottom cross-sectional view of the outer rotor ring according to an embodiment of the present invention is shown.

[0029] Figure 5 A cross-sectional schematic diagram of the stator base according to an embodiment of the present invention is shown.

[0030] Figure 6 A schematic diagram showing the connection between the winding module and the stator mounting ring according to an embodiment of the present invention is shown.

[0031] Figure 7 A cross-sectional schematic diagram of a winding module according to an embodiment of the present invention is shown.

[0032] Figure 8 A schematic diagram of the internal cooling mechanism according to an embodiment of the present invention is shown.

[0033] Figure 9 A bottom view schematic diagram of the outer rotor head according to an embodiment of the present invention is shown.

[0034] Figure 10 A schematic diagram of the structure of the inner rotor section according to an embodiment of the present invention is shown.

[0035] In the diagram: 100, stator base; 110, first bearing housing; 120, stator mounting ring; 130, heat dissipation vent; 131, threaded eddy groove; 140, Hall sensor; 200, neodymium magnet; 210, back plate; 220, winding backbone; 230, isolation tooth; 240, internal cooling mechanism; 241, horizontal tube; 242, U-shaped tube; 243, intermediate tube; 250, winding body; 300, outer rotor ring; 310, outer rotor head; 320, heat dissipation inlet; 330, suction funnel; 400, inner rotor section; 410, snap-fit ​​section; 420, snap-fit ​​head; 430, rotating shaft; 440, annular top groove; 450, side through groove; 500, electronic speed controller. Detailed Implementation

[0036] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0037] This invention provides a split-type thermal expansion-resistant motor for robots, as exemplified by... Figure 1 , Figure 2 and Figure 3 As shown, a stator base 100 with a disc-shaped structure is included. A first bearing seat 110 is fixedly installed at the top periphery of the stator base 100, and the central axis of the first bearing seat 110 coincides with the central axis of the stator base 100.

[0038] For example, an outer rotor ring 300 with a circular structure is rotatably connected to the first bearing housing 110. An outer rotor head 310 with a horn-shaped structure is fixedly installed on the top of the outer rotor ring 300. Several sets of heat dissipation air inlets 320 are distributed in a circular array on the side walls of the outer rotor head 310.

[0039] For example, a number of neodymium magnet blocks 200 are arranged in a ring array on the inner wall of the outer rotor ring 300. The number of neodymium magnet blocks 200 is even, and the magnetic poles of two adjacent groups of neodymium magnet blocks 200 are set oppositely.

[0040] For example, a stator mounting ring 120 with a circular structure is concentrically arranged at the center of the stator base 100, and several sets of winding modules are distributed in a circular array on the outer wall of the stator mounting ring 120. The number of winding modules is preferably 12 sets, which is less than the number of neodymium magnets 200. The winding modules are electromagnetically connected to the neodymium magnets 200.

[0041] For example, an electronic speed controller 500 is provided on one side of the stator base 100, and each winding module is electrically connected to the electronic speed controller 500.

[0042] For example, an inner rotor portion 400 is rotatably connected to the central axis of the stator mounting ring 120. The bottom of the inner rotor portion 400 is rotatably connected to the stator base 100, and the top extends directly above the outer rotor head 310. The inner rotor portion 400 is fixedly connected to the outer rotor head 310.

[0043] By supplying power to each group of winding modules, electromagnetic force is generated. Utilizing the electromagnetic connection between the winding modules and the neodymium magnets 200, alternating attraction and repulsion are generated sequentially on each group of neodymium magnets 200 with opposite magnetic poles, thereby driving the outer rotor ring 300, outer rotor head 310, and inner rotor section 400 to rotate.

[0044] For example, such as Figure 4 and Figure 5 As shown, the stator base 100 has several sets of heat dissipation vents 130 arranged in a ring array at its bottom. The inner diameter of the top of each heat dissipation vent 130 is larger than its inner diameter at the bottom. Threaded vortex grooves 131 are formed on the inner wall of each heat dissipation vent 130, and the threaded vortex grooves 131 have a spiral structure.

[0045] The heat dissipation vent 130 has a trumpet-shaped structure, with a larger inner diameter on the side closer to the inner cavity of the outer rotor ring 300. This causes the hot air to gradually accelerate as it is discharged. Due to the influence of the threaded vortex groove 131, the hot air forms a vortex while accelerating and is discharged in a concentrated manner, which facilitates heat energy collection and the treatment of hot air.

[0046] For example, a Hall sensor 140 is fixedly mounted on the stator base 100, and the Hall sensor 140 is electromagnetically connected to each set of neodymium magnets 200. The Hall sensor 140 is used to sense the positive and negative polarity of the set of neodymium magnets 200 directly above it to map the rotational position of the inner rotor section 400, the outer rotor ring 300, and the outer rotor head 310, so as to accurately control the rotation angle of the inner rotor section 400.

[0047] For example, such as Figure 6 and Figure 7As shown, the winding module includes a back plate 210. Isolation teeth 230 are provided on the side of the back plate 210 away from the central axis of the stator mounting ring 120. A set of winding support rods 220 are horizontally arranged at both the upper and lower edges of the back plate 210, and the other ends of both sets of winding support rods 220 are mounted on the isolation teeth 230. An internal cooling mechanism 240 is provided between the two sets of winding support rods 220. The outer shell of the internal cooling mechanism 240 is made of insulating material. Both the input and output ends of the internal cooling mechanism 240 extend to the outside of the stator base 100 and are connected to a coolant storage component.

[0048] For example, the winding module further includes a winding body 250, the two ends of which are respectively wound around two sets of winding core rods 220.

[0049] Specifically, the winding directions of the two adjacent winding bodies 250 are opposite, and they are connected in pairs to form a winding mechanism. Each winding is connected to the opposite winding to form a working unit. The working unit is electrically connected to the electronic speed controller 500 through a set of wires.

[0050] First, the electronic speed controller 500 supplies power to one group of working units. After the working unit is powered on, its windings generate electromagnetic force. Since each group of windings consists of two winding bodies 250 with opposite winding directions, the electromagnetic force acts in opposite directions. It uses the repulsive and attractive forces of the neodymium magnet 200 closest to the two sets of magnetic poles opposite to the windings to drive the inner rotor 400, outer rotor ring 300 and outer rotor head 310 to rotate. Then, the Hall sensor 140 senses the direction of the magnetic poles of the neodymium magnet 200 passing directly above it, thereby sending a signal to the electronic speed controller 500 and causing the electronic speed controller 500 to supply power to each group of working units in the same direction in sequence, so that each group of neodymium magnet 200 is always affected by repulsive and attractive forces. Furthermore, since the number of neodymium magnets 200 is greater than the number of winding modules, the neodymium magnets 200 cannot correspond one-to-one with the winding modules of the same pole. Therefore, when energized, the rotor will always maintain its rotation state.

[0051] Compared with traditional brushed motors, this embodiment uses a brushless motor, which reduces the use of carbon brushes and commutators, thereby reducing component wear and increasing the motor's service life. Furthermore, the non-contact conductive design also reduces noise generation.

[0052] For example, such as Figure 8 As shown, the internal cooling mechanism 240 is a three-dimensional tubular structure, including several sets of horizontally arranged horizontal pipes 241, which are equally spaced along the vertical direction. A U-shaped pipe 242 connects each adjacent set of horizontal pipes 241, and an intermediate pipe 243 connects each set of U-shaped pipes 242 at the same height.

[0053] The traditional one-piece winding frame is replaced with two sets of winding skeletons 220 that are symmetrically arranged on the top and bottom. An internal cooling mechanism 240 is installed between the two sets of winding skeletons 220. When working, the external coolant storage component is used to supply coolant to each set of horizontal pipes 241, U-shaped pipes 242 and intermediate pipes 243 to exchange heat with the winding body 250 from the inside.

[0054] For example, such as Figure 9 As shown, an air intake 330 is movably installed at one end of the heat dissipation air intake 320 near the inner cavity of the outer rotor head 310. The bottom of the air intake 330 extends obliquely towards the central axis of the outer rotor head 310. The air intake 330 has a funnel-shaped structure and is a mesh structure as a whole.

[0055] While heat exchange occurs through the internal cooling mechanism 240, external cold air is introduced through the heat dissipation inlet 320 and hot air is discharged through the heat dissipation outlet 130, thus cooling each winding module from the outside. This makes the heat exchange more three-dimensional. Furthermore, both the heat dissipation inlet 320 and the heat dissipation outlet 130 are funnel-shaped structures, allowing cold air to enter quickly and hot air to exit rapidly, thereby improving heat exchange efficiency. This solves the problem of thermal expansion caused by poor heat dissipation in traditional motors.

[0056] For example, such as Figure 10 As shown, the inner rotor section 400 includes a snap-fit ​​section 410, which is rotatably connected to the stator base 100. A snap-fit ​​head 420 is movably installed at the top center of the snap-fit ​​section 410. A rotating shaft 430 is fixedly installed at the top center of the snap-fit ​​head 420. The rotating shaft 430 is fixedly connected to the outer rotor head 310. The top of the rotating shaft 430 extends directly above the outer rotor head 310, and an annular top groove 440 is concentrically arranged at its top port. Several sets of side through grooves 450 are distributed in a circular array around the top edge of the rotating shaft 430. The top of the side through grooves 450 is an open structure, and the side through grooves 450 communicate with the annular top grooves 440.

[0057] An annular top groove 440 is provided at the top port of the rotating shaft 430, and multiple sets of side through grooves 450 are distributed in a circular array around it. This allows the workpiece to be fixed on the rotating shaft 430 from multiple directions, including inside, outside, and sides. Even if the rotating shaft 430 experiences aging and wear due to high-speed rotation, the workpiece will not slip or shift. Compared with the traditional design where only one direction is set as a plane, this improves the service life and wear resistance of the rotating shaft.

[0058] The above embodiments have the following beneficial effects:

[0059] The traditional one-piece winding frame is replaced with two symmetrical sets of winding rods 220, and an internal cooling mechanism 240 is installed between the two sets of winding rods 220. During operation, external coolant storage components supply coolant to each set of horizontal pipes 241, U-shaped pipes 242, and intermediate pipes 243, facilitating heat exchange with the winding body 250 from within. Simultaneously, external cold air is introduced through the heat dissipation inlet 320 and hot air is discharged through the heat dissipation outlet 130, thus cooling each winding module from the outside and making the heat exchange more three-dimensional. Furthermore, both the heat dissipation inlet 320 and the heat dissipation outlet 130 are funnel-shaped structures, allowing cold air to enter quickly and hot air to exit quickly, thereby improving heat exchange efficiency. This solves the problem of thermal expansion caused by poor heat dissipation in traditional motors.

[0060] The heat dissipation vent 130 has a trumpet-shaped structure, with a larger inner diameter on the side closer to the inner cavity of the outer rotor ring 300. This causes the hot air to gradually accelerate as it is discharged. Due to the influence of the threaded vortex groove 131, the hot air forms a vortex while accelerating and is discharged in a concentrated manner, which facilitates heat energy collection and the treatment of hot air.

[0061] An annular top groove 440 is provided at the top port of the rotating shaft 430, and multiple sets of side through grooves 450 are distributed in a circular array around it. This allows the workpiece to be fixed on the rotating shaft 430 from multiple directions, including inside, outside, and sides. Even if the rotating shaft 430 experiences aging and wear due to high-speed rotation, the workpiece will not slip or shift. Compared with the traditional design where only one direction is set as a plane, this improves the service life and wear resistance of the rotating shaft.

[0062] Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A split heat expansion-proof motor for robots, comprising a stator base, characterized in that: A stator mounting ring with a circular structure is concentrically arranged at the center of the stator base, and several sets of winding modules are distributed in a ring array on the outer wall of the stator mounting ring. The winding module includes a back plate, on the side of the back plate away from the central axis of the stator mounting ring, an isolation tooth is provided, and a set of winding ribs are horizontally provided at both the upper and lower edges of the back plate, with the other ends of the two sets of winding ribs mounted on the isolation tooth; an internal cooling mechanism is provided between the two sets of winding ribs, and the outer shell of the internal cooling mechanism is made of insulating material; The internal cooling mechanism is a three-dimensional tubular structure, including several sets of horizontal pipes arranged horizontally, with the sets of horizontal pipes arranged at equal intervals along the vertical direction; a set of U-shaped pipes connects each adjacent set of horizontal pipes, and a set of intermediate pipes connects each set of U-shaped pipes at the same height.

2. The split heat-proof expansion motor for robots according to claim 1, characterized in that: A first bearing seat is fixedly installed at the top periphery of the stator base, and the central axis of the first bearing seat coincides with the central axis of the stator base; an outer rotor ring with a circular structure is rotatably connected to the first bearing seat, and an outer rotor head with a trumpet-shaped structure is fixedly installed on the top of the outer rotor ring, and several sets of heat dissipation air inlets are distributed in a circular array on the side walls around the outer rotor head.

3. The split heat-expansion-proof motor for robots according to claim 2, characterized in that: An air intake funnel is movably installed at one end of the heat dissipation air intake hole near the inner cavity of the outer rotor head. The bottom of the air intake funnel extends at an inclination towards the central axis of the outer rotor head. The air intake funnel has a trumpet-shaped structure and the entire air intake funnel has a mesh-like structure.

4. The split heat-proof expansion motor for robots according to claim 2, characterized in that: The inner wall of the outer rotor ring has several groups of neodymium magnets arranged in a ring array. The number of neodymium magnets is even, and the magnetic poles of adjacent groups of neodymium magnets are set oppositely. The number of winding modules is 12, which is less than the number of neodymium magnets. The winding modules are electromagnetically connected to the neodymium magnets.

5. The split heat expansion prevention motor for robot according to claim 2, characterized in that: An electronic speed controller is provided on one side of the stator base, and each winding module is electrically connected to the electronic speed controller.

6. The split heat-expansion-proof motor for robots according to claim 1, characterized in that: The stator base has several sets of heat dissipation vents arranged in a ring array at its bottom. The inner diameter of the top of each heat dissipation vent is larger than its inner diameter at the bottom. Threaded vortex grooves are formed on the inner wall of each heat dissipation vent, and the threaded vortex grooves have a spiral structure.

7. The split heat-expansion-proof motor for robots according to claim 4, characterized in that: A Hall sensor is fixedly installed on the stator base, and the Hall sensor is electromagnetically connected to each group of neodymium magnets.

8. The split heat-expansion-proof motor for robots according to claim 1, characterized in that: An electronic speed controller is provided on one side of the stator base, and the winding module also includes a winding body, with both ends of the winding body wound around two sets of winding backbones respectively. The winding directions of two adjacent sets of winding bodies are opposite, and they are connected in pairs to form a winding mechanism. Each set of windings is connected to the opposite set of windings to form a working unit. The working unit is electrically connected to the electronic speed controller through a set of wires.

9. The split heat-expansion-proof motor for robots according to claim 1, characterized in that: An inner rotor is rotatably connected to the central axis of the stator mounting ring. The bottom of the inner rotor is rotatably connected to the stator base, and the top extends directly above the outer rotor head. The inner rotor is fixedly connected to the outer rotor head.

10. The split heat-expansion-proof motor for robots according to claim 9, characterized in that: The inner rotor part comprises a clamping part which is rotationally connected to the stator base, and a clamping head movably installed at the center of the top of the clamping part; a rotating shaft is fixedly installed at the center of the top of the clamping head, the rotating shaft is fixedly connected with the outer rotor head, the rotating shaft extends to the top of the outer rotor head, and an annular top groove is concentrically arranged at the top port of the rotating shaft; a plurality of groups of side through grooves are annularly arranged at the periphery of the top of the rotating shaft, the top of the side through groove is of an open structure, and the side through groove is communicated with the annular top groove.

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