Outer rotor structure, brushless motor and unmanned aerial vehicle

Abstract

This utility model belongs to the field of UAV power motor technology, and discloses an external rotor structure, a brushless motor, and a UAV. The external rotor structure is composed of a shaft, a fan, a housing, a cage, and magnets. The cage is ring-shaped and fixed inside the housing, with multiple protrusions extending downwards on its lower side to hold the magnets in place. The fan has a top plate on its upper side and fan blades on its lower side. The top plate of the fan is fixed to the top surface of the housing, and the shaft is fixed inside the housing via a shaft mounting part. This external rotor structure achieves the installation of the shaft and magnets through the assembly structure of the fan, housing, and cage. Furthermore, the structure of the fan, housing, and cage is relatively simple, allowing the cage and fan to be manufactured using injection molding, and the housing to be manufactured using deep drawing, effectively reducing manufacturing costs and improving the production efficiency of the UAV. At the same time, the fan structure is retained to ensure the motor's heat dissipation performance.

Description

Technical Field

[0001] This utility model belongs to the field of drone power motor technology, specifically relating to an external rotor structure, a brushless motor, and a drone. Background Technology

[0002] The outer rotor of a drone rotor motor consists of a shell, rotor support, and magnets, or a combination of a shell, rotor support, magnets, and a fan. In existing technologies, the outer shell and rotor support are made of different materials and both require machining. Furthermore, the rotor support is designed with multiple magnet positioning teeth and centrifugal fan blades, resulting in a complex shape. These structural components all require machining from solid raw materials, leading to long turning and milling times, low production efficiency, significant raw material waste, and high costs. Utility Model Content

[0003] The technical problem to be solved by this utility model is to overcome the shortcomings of the existing technology, which requires complex machining processes for the outer shell and rotor support of the drone power motor, resulting in high costs. In this way, an outer rotor structure, a brushless motor and a drone are provided.

[0004] An external rotor structure includes a shaft, a fan, a housing, a cage, and a magnet. A shaft mounting portion is formed in the center of the top surface of the housing, through which the shaft passes and is fixed to the housing. The cage is annular and fixed to the inner side of the housing, with multiple protrusions extending downwards on its lower side to hold the position of the magnet. The magnet is fixed to the inner side of the housing. The shaft is fixed inside the housing via the shaft mounting portion. A top plate is formed on the upper side of the fan, and the top plate is fixed to the top surface of the housing. Fan blades are formed on the lower side of the fan, and these blades form an axial stepped structure. The stepped structure engages with a slot formed on the top surface of the housing, creating a gap between the top plate of the fan and the top surface of the housing.

[0005] Furthermore, the rotating shaft is fixed to the rotating shaft mounting part of the housing by an interference fit.

[0006] Furthermore, a positioning post is formed on the upper side of the top surface of the housing, and the positioning post is tapped; a positioning hole is formed on the top plate of the fan; a screw passes through the positioning hole and cooperates with the positioning post to lock the fan onto the housing.

[0007] Furthermore, a pivot positioning part is formed at the center of the top plate of the fan; the fan blades extend circumferentially from the pivot positioning part to the edge of the top plate, and a stepped structure is formed in the middle section of the fan blades; the fan-shaped annular groove formed on the top surface of the outer casing cooperates with the stepped structure.

[0008] Furthermore, it also includes a bushing, through which the rotating shaft passes and is fixed, and the bushing is fixed to the housing via a rotating shaft mounting portion.

[0009] Furthermore, the bushing is fixed to the rotating shaft with an interference fit, and the bushing is fixed to the rotating shaft mounting part of the housing by screws.

[0010] Furthermore, a stop is provided on the top surface of the housing, and the stop is interference-fitted with the bushing.

[0011] Furthermore, the cage and the fan are injection molded structures, while the outer shell is formed by deep drawing.

[0012] A brushless motor, wherein the outer rotor structure of the brushless motor is as described above.

[0013] A drone includes the brushless motor described above, which provides flight power to the drone.

[0014] Beneficial Effects: This utility model discloses an external rotor structure, a brushless motor, and a drone. The external rotor structure is composed of a shaft, a fan, a housing, a cage, and magnets. The cage is ring-shaped and fixed inside the housing, with multiple protrusions extending downwards on its lower side to hold the magnets in place. The fan has a top plate on its upper side and fan blades on its lower side. The top plate of the fan is fixed to the top surface of the housing, and the shaft is fixed inside the housing via a shaft mounting part. This external rotor structure achieves the installation of the shaft and magnets through the assembly structure of the fan, housing, and cage. Furthermore, the structure of the fan, housing, and cage is relatively simple, allowing the cage and fan to be manufactured using injection molding, and the housing to be manufactured using deep drawing, effectively reducing manufacturing costs and improving the production efficiency of the drone. Simultaneously, the fan structure is retained, ensuring the motor's heat dissipation performance. Attached Figure Description

[0015] To more clearly illustrate the technical solutions in the embodiments of this application 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 only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0016] Figure 1 This is a schematic diagram of the exploded structure of the outer rotor of this utility model;

[0017] Figure 2 This is a schematic diagram of the external rotor assembly structure of this utility model;

[0018] Figure 3 This is a schematic diagram of the outer shell structure of this utility model;

[0019] Figure 4 This is a schematic diagram of the fan structure of this utility model;

[0020] Figure 5 This is a schematic diagram of the fan structure from another angle of this utility model;

[0021] Figure 6 This is a schematic diagram of the cage structure of this utility model;

[0022] Figure 7 This is a schematic diagram of the exploded structure of the motor according to this utility model;

[0023] Figure 8 This is a schematic diagram of the motor assembly structure of this utility model.

[0024] Explanation of reference numerals in the attached drawings: 1. Outer shell; 11. Top surface; 111. Shaft mounting part; 112. Positioning post; 113. Slot; 2. Fan; 21. Top plate; 211. Shaft positioning part; 212. Positioning hole; 22. Fan blade; 221. Stepped structure; 3. Shaft; 4. Cage; 5. Magnet. Detailed Implementation

[0025] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application are described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of this application. However, this application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this application. Therefore, this application is not limited to the specific embodiments disclosed below.

[0026] In the description of this application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0027] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0028] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0029] Example 1:

[0030] Reference Figures 1-6 As shown, an external rotor structure includes a rotating shaft 3, a fan 2, a housing 1, a retainer 4, and a magnet 5. A rotating shaft mounting portion 111 is formed in the middle of the top surface 11 of the housing 1. The rotating shaft 3 passes through the rotating shaft mounting portion and is fixed to the housing 1. The retainer 4 is annular and fixed to the inner side of the housing 1, with multiple protrusions extending downwards on its lower side to hold the position of the magnet 5. The magnet 5 is fixed to the inner side of the housing 1. The rotating shaft 3 is fixed inside the housing 1 via the rotating shaft mounting portion 111. A top plate 21 is formed on the upper side of the fan 2, and the top plate 21 of the fan 2 is fixed to the top surface 11 of the housing 1. A fan blade 22 is formed on the lower side of the fan 2, and the fan blade 22 forms an axial stepped structure 221. The stepped structure 221 is engaged with a slot 113 formed on the top surface 11 of the housing 1, creating a gap between the top plate 21 of the fan 2 and the top surface 11 of the housing 1.

[0031] In this embodiment, the rotating shaft 3 is fixed to the rotating shaft mounting part 111 of the outer casing 1 by an interference fit.

[0032] Specifically, a positioning post 112 is formed on the upper side of the top surface 11 of the outer casing 1, and the positioning post 112 is tapped; a positioning hole 212 is formed on the top plate 21 of the fan 2; a screw passes through the positioning hole 212 and engages with the positioning post 112 to lock the fan 2 onto the outer casing 1. In this embodiment, a circular mounting plate is formed in the middle of the top surface 11 of the outer casing 1, and a shaft mounting part 111 for mounting the shaft 3 is formed in the center of the mounting plate. Four positioning posts 112 are formed on the periphery of the mounting plate. The mounting plate is fixed to the edge of the top surface 11 by six spokes, and a positioning post 112 is formed in the middle section of each spoke. Six slots 113 are formed between the mounting plate, the spokes, and the edge of the top surface 11.

[0033] The top plate 21 of the fan 2 forms a pivot positioning part 211 at its center; the fan blades 22 extend circumferentially from the pivot positioning part 211 to the edge of the top plate 21, and the middle section of the fan blades 22 forms a stepped structure 221; the top surface 11 of the outer casing 1 forms a fan-shaped annular slot 113 that mates with the stepped structure 221. The top plate 21 of the fan 2 forms ten positioning holes 212 corresponding to the ten positioning posts 112 on the top surface 11 of the outer casing 1, and eighteen fan blades 22 extend from the edge of the pivot positioning part 211 of the top plate 21 to the edge of the top plate 21. The fan blades 22 extend axially, and the middle sections of twelve fan blades 22 extend axially to form stepped structures 221, with every two stepped structures 221 fitting into one slot 113.

[0034] In this embodiment, the cage 4 and the fan 2 are injection molded structures, while the outer shell 1 is manufactured using a deep-drawing process. These processes significantly reduce manufacturing costs and time, thereby effectively improving the production efficiency of the UAV's power motor.

[0035] As a preferred embodiment, the retainer 4 is provided with 28 protrusions, and 28 magnets 5 are fixed by the grooves formed between these protrusions.

[0036] In a preferred embodiment, during installation, the retainer 4 is fixed inside the housing 1, and the magnet 5 is positioned by the retainer 4 and fixed inside the housing 1. The stepped structure 221 of the fan blade 22 is engaged in the slot 113 on the top surface 11 of the housing 1. The fan 2 is locked onto the housing 1 by screws passing through the positioning hole 212 and engaging with the positioning post 112. The shaft 3 is then fixed to the shaft mounting part 111 on the top surface 11 of the housing 1 by interference fit through the shaft positioning part 211 of the fan 2, thus completing the assembly of the outer rotor structure.

[0037] Example 2:

[0038] In this embodiment, the rotating shaft 3 is not fixed to the rotating shaft mounting part 111 of the outer casing 1 by interference fit, and also includes a bushing. The rotating shaft 3 passes through the bushing and is fixed to the bushing. The bushing is fixed to the outer casing 1 through the rotating shaft mounting part 111.

[0039] Specifically, the top surface 11 of the outer casing 1 is provided with a stop, which is interference-fitted with the bushing. The stop ensures the coaxiality of the rotating shaft 3 and the outer casing 1. The bushing is fixed to the rotating shaft 3 by the interference fit, and the bushing is fixed to the rotating shaft mounting part 111 of the outer casing 1 by screws. In this embodiment, the rotating shaft mounting part 111 of the outer casing 1 has a threaded hole for fixing the bushing with screws.

[0040] Example 3:

[0041] Reference Figure 7 and Figure 8 As shown, this embodiment provides a brushless motor, the external rotor structure of which is the same as that described in Embodiment 1 or Embodiment 2. The brushless motor is formed by assembling a motor stator and the external rotor structure described in Embodiment 1 or Embodiment 2.

[0042] Example 4:

[0043] A drone includes the brushless motor described above, which provides flight power to the drone.

[0044] This invention provides an external rotor structure, a brushless motor, and a drone. The external rotor structure is composed of a shaft 3, a fan 2, a housing 1, a cage 4, and a magnet 5. The cage 4 is ring-shaped and fixed inside the housing 1, with multiple protrusions extending downwards on its lower side to hold the position of the magnet 5. The fan 2 has a top plate 21 on its upper side and fan blades 22 on its lower side. The top plate 21 of the fan 2 is fixed to the top surface 11 of the housing 1. The shaft 3 is fixed inside the housing 1 via a shaft mounting part 111. This external rotor structure achieves the installation of the shaft 3 and the magnet 5 through the assembly structure of the fan 2, housing 1, and cage 4. The structure of the fan 2, housing 1, and cage 4 is relatively simple, allowing the cage 4 and fan 2 to be manufactured using injection molding, and the housing 1 to be manufactured using deep drawing, effectively reducing manufacturing costs and improving the production efficiency of the drone. At the same time, the fan 2 structure is retained, ensuring the motor's heat dissipation performance.

[0045] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0046] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. An external rotor structure, characterized in that, Includes a rotating shaft (3), a fan (2), a housing (1), a retainer (4), and a magnet (5); a rotating shaft mounting part (111) is formed in the middle of the top surface (11) of the housing (1), the rotating shaft (3) passes through the rotating shaft mounting part (111) and is fixed to the housing (1); the retainer (4) is annular and fixed to the inside of the housing (1), with multiple protrusions extending downwards on its lower side to hold the position of the magnet (5); the magnet (5) is fixed to the inside of the housing (1); the rotating shaft (3) passes through the rotating shaft mounting part (111) and is fixed to the housing (1); 111) Fixed inside the outer casing (1); a top plate (21) is formed on the upper side of the fan (2), and the top plate (21) of the fan (2) is fixed to the top surface (11) of the outer casing (1); a fan blade (22) is formed on the lower side of the fan (2), and the fan blade (22) forms an axial stepped structure (221), and the stepped structure (221) is engaged in the slot (113) formed on the top surface (11) of the outer casing (1), so that the top plate (21) of the fan (2) and the top surface (11) of the outer casing (1) form a gap.

2. The external rotor structure according to claim 1, characterized in that, The rotating shaft (3) is fixed to the rotating shaft mounting part (111) of the outer shell (1) by an interference fit.

3. The external rotor structure according to claim 1, characterized in that, A positioning post (112) is formed on the upper side of the top surface (11) of the outer casing (1), and the positioning post (112) is tapped; a positioning hole (212) is formed on the top plate (21) of the fan (2); a screw passes through the positioning hole (212) and cooperates with the positioning post (112) to lock the fan (2) onto the outer casing (1).

4. The external rotor structure according to claim 1, characterized in that, The top plate (21) of the fan (2) forms a pivot positioning part (211) at its center; the fan blade (22) extends circumferentially from the pivot positioning part (211) to the edge of the top plate (21), and the middle section of the fan blade (22) forms a stepped structure (221); the top surface (11) of the outer shell (1) forms a fan-shaped groove (113) that cooperates with the stepped structure (221).

5. An external rotor structure according to claim 1, characterized in that, It also includes a bushing, through which the rotating shaft (3) passes and is fixed, and the bushing is fixed to the housing (1) via the rotating shaft mounting part (111).

6. An external rotor structure according to claim 5, characterized in that, The bushing is fixed to the rotating shaft (3) by an interference fit, and the bushing is fixed to the rotating shaft mounting part (111) of the outer shell (1) by screws.

7. An external rotor structure according to claim 6, characterized in that, The top surface (11) of the outer casing (1) is provided with a stop, which is interference-fitted with the bushing.

8. An external rotor structure according to claim 1, characterized in that, The retainer (4) and the fan (2) are injection molding structures, and the outer shell (1) is a mold drawing structure.

9. A brushless motor, characterized in that, The external rotor structure of the brushless motor is as described in any one of claims 1 to 8.

10. A drone, characterized in that, The drone includes a brushless motor as described in claim 9, the brushless motor providing flight power to the drone.

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