High-speed brushless dc planetary reducer motor

Abstract

This invention discloses a high-speed brushless DC planetary geared motor, including a housing assembly and a motor front end cover. A rotor assembly is housed within the housing assembly, and an intermediate shaft is rotatably mounted on the motor front end cover. A gap space is formed between the rotor assembly and the motor front end cover, and a heat dissipation assembly is disposed within this gap space. The heat dissipation assembly includes a first-stage heat dissipation component and a second-stage heat dissipation component arranged sequentially along the axial direction of the intermediate shaft. The first-stage heat dissipation component has heat dissipation fins radially distributed along the intermediate shaft with a preset rotation direction to provide the main thrust of the airflow. Multiple guide vanes are disposed on the outer periphery of the second-stage heat dissipation component. These guide vanes have curved surfaces with a preset curvature, which guide the lateral flow rotation of the airflow. By generating and stabilizing the main airflow in the first stage and guiding and redirecting the flow direction in the second stage, the generation and directional guidance of the airflow are combined, greatly reducing airflow convection, lowering motor noise, and improving motor performance.

Description

Technical Field

[0001] This invention relates to the field of motor technology, and in particular to a high-speed brushless DC planetary geared motor. Background Technology

[0002] Brushless motors, due to their small size, high efficiency, and good control precision, are widely used in automated equipment and small household appliances, such as floor scrubbers and washer-dryer combos. However, during high-speed operation and prolonged continuous work, these motors can experience excessive temperature rise due to heat generated in the stator windings and rotor assembly, leading to performance degradation, shortened lifespan, and even component damage. Therefore, effectively designing efficient and low-noise heat dissipation for brushless motors within limited structural space and weight constraints has been a crucial and long-standing issue of concern in the industry.

[0003] In existing technologies, the common approach to heat dissipation in brushless motors is to install fan-blade-like heat sinks on the rotor. This utilizes the centrifugal force generated by the rotor's rotation to drive airflow, thereby conducting and expelling heat from the motor cavity. The core focus of this type of structure is "how to generate airflow," typically increasing air volume by increasing the blade angle, number, or shape. However, this method of relying solely on rotor heat sinks to generate airflow leads to significant airflow convection and turbulence within the cavity during high-speed operation, generating substantial aerodynamic noise. Simultaneously, the high-speed jet of air impacts the housing's heat dissipation vents, further causing aerodynamic noise and vibration, thus reducing the overall performance of the motor and making it difficult to simultaneously achieve efficient heat dissipation and low-noise operation.

[0004] Therefore, it is necessary to improve and optimize the existing brushless motor structure to solve the technical problem of high noise during heat dissipation. Summary of the Invention

[0005] The purpose of this invention is to provide a high-speed brushless DC planetary geared motor to solve the above-mentioned technical problems.

[0006] To achieve this objective, the present invention adopts the following technical solution: A high-speed brushless DC planetary geared motor includes a housing assembly and a motor front cover. The housing assembly houses a rotor assembly, and an intermediate shaft is rotatably mounted on the motor front cover. A gap space is formed between the rotor assembly and the front end cover of the motor, and a heat dissipation component is provided in the gap space. The heat dissipation assembly includes a first-stage heat dissipation component and a second-stage heat dissipation component arranged sequentially along the axial direction of the intermediate shaft. The first-stage heat dissipation component is provided with heat dissipation fins that are radially distributed along the intermediate shaft and have a preset rotation direction to provide the main thrust of airflow. The outer periphery of the second-stage heat sink is provided with multiple guide vanes, each guide vane having a curved surface with a preset curvature, the curved surface being used to guide the lateral flow direction of the airflow.

[0007] Optionally, a heat dissipation part is provided at a preset position of the housing assembly, and the second-stage heat dissipation component is disposed on one end of the intermediate shaft near the heat dissipation part; The heat dissipation part includes at least one heat dissipation through hole, the length direction of the heat dissipation through hole is extended in a spiral manner, and the heat dissipation through hole has a preset spiral angle so that the airflow direction of the curved surface is close to parallel to the length direction of the heat dissipation through hole.

[0008] Optionally, the inner diameter of the rotor assembly is larger than the outer diameter of the intermediate shaft, so that a gap is formed between the rotor assembly and the intermediate shaft, and the first-stage heat sink is installed in the gap; wherein, the first-stage heat sink is connected to the intermediate shaft, or is integrally formed with the rotor assembly.

[0009] Optionally, the first-stage heat dissipation component includes an inner ring and an outer ring spaced apart, with heat dissipation fins disposed between the inner ring and the outer ring. The inner ring is fixedly connected to the intermediate shaft, and the outer ring is fixedly connected to the inner wall of the rotor assembly.

[0010] Optionally, the heat dissipation fins include a first curved surface and a second curved surface, and the first curved surface and the second curved surface are connected by a wedge-shaped surface; The first curved surface is a concave curved surface, and the second curved surface is a convex curved surface, and both the first curved surface and the second curved surface extend along the axial direction of the intermediate axis; the wedge-shaped surface gradually narrows from the first curved surface to the second curved surface to form a guide channel inside the heat dissipation fins, which is used to guide the airflow along the guide channel.

[0011] Optionally, a rear end cover of the motor is provided at one end of the housing assembly away from the front end cover of the motor, and a plurality of air inlets are provided on the rear end cover of the motor, and the plurality of air inlets are arranged around the intermediate shaft; The air inlet is positioned toward the spacer to form an airflow channel that flows sequentially from the air inlet, the spacer, to the gap space.

[0012] Optionally, the intermediate shaft is connected to the rear end cover of the motor via a first bearing, and a spring is provided between the first bearing and the rotor assembly. The spring is used to extend the first bearing to provide preload to the first bearing.

[0013] Optionally, the second-stage heat dissipation component includes a connecting sleeve, which is fixedly sleeved on the intermediate shaft. The outer side wall of the connecting sleeve is provided with a plurality of support ribs along its circumferential direction, and one end of the support rib is connected to a connecting ring. The guide vanes are evenly distributed on the connecting ring and extend along the axial direction of the intermediate shaft. The curved surface extends obliquely from one end of the guide vane to form a spiral air guiding structure around the intermediate shaft.

[0014] Optionally, it also includes a stator assembly and a PCB board disposed at one end of the stator assembly, wherein a cutout groove is provided at a preset position on the PCB board; The stator assembly has a positioning buckle on its outer side wall, and the housing assembly has a slot that engages with the positioning buckle. The positioning buckle and the slot cooperate to achieve a fixed connection between the stator assembly and the housing assembly.

[0015] Optionally, it also includes a reduction gear assembly disposed on the front end cover of the motor, wherein a first gear is disposed at one end of the intermediate shaft; The deceleration assembly includes a main wheel, which has a first inner cavity. An internal gear portion is provided on the side wall of the first inner cavity. The internal gear portion is meshed with a plurality of second gears, and the plurality of second gears mesh with the first gear respectively. The first inner cavity is rotatably connected to a connecting plate, and a plurality of second gears are respectively mounted on the connecting plate. The connecting plate is provided with an output shaft for power output.

[0016] Compared with the prior art, the present invention has the following beneficial effects: When the motor is working, when the intermediate shaft rotates synchronously with the rotor, the first-stage heat sink first drives the air with rotation, generating radial and tangential momentum components on the heat sink fins, forming a main airflow with a main thrust along the axial direction and a preset vortex direction; this main airflow enters the gap area near the front end cover along the axial direction and reaches the second-stage heat sink. The outer peripheral guide vanes of the second-stage heat sink capture and gradually change the flow direction of the main airflow with their arc-shaped curved surfaces, smoothly guiding the originally axial airflow into a lateral / vortex flow, so that the airflow flows along the direction matching the heat sink holes on the side wall of the housing and is discharged through the heat sink holes, thereby realizing the circulation exchange and continuous convective heat transfer of the air inside and outside the motor cavity, while avoiding the generation of strong turbulence and violent wakes. The multi-stage heat dissipation structure of this solution, through the synergistic work of the first stage generating and stabilizing the main airflow and the second stage guiding and changing the flow direction, greatly reduces the generation of airflow convection, significantly improves the heat transfer efficiency, and reduces motor noise and improves motor performance. Attached Figure Description

[0017] 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 only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] The structures, proportions, sizes, etc., shown in the accompanying drawings of this specification are only for the purpose of assisting those skilled in the art in understanding and reading the content disclosed in the specification, and are not intended to limit the conditions under which the present invention can be implemented. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in the proportions, or adjustments to the size, without affecting the effects and objectives that the present invention can produce, should still fall within the scope of the technical content disclosed in the present invention.

[0019] Figure 1 This is a schematic diagram of the overall structure of the high-speed brushless DC planetary geared motor in this embodiment. Figure 2 This is a cross-sectional structural diagram of the high-speed brushless DC planetary geared motor in this embodiment 1; Figure 3 This is a schematic diagram of the airflow channel in the cross-section of the high-speed brushless DC planetary geared motor of this embodiment 1; Figure 4 This is an exploded structural diagram of the components of the high-speed brushless DC planetary geared motor in this embodiment. Figure 5 This is a schematic diagram of the heat dissipation assembly of the high-speed brushless DC planetary geared motor in this embodiment 1; Figure 6 This is a schematic diagram of the first-stage heat sink of the high-speed brushless DC planetary geared motor in this embodiment. Figure 7 This is a partial cross-sectional view of the heat sink of the first stage of the high-speed brushless DC planetary gear motor in this embodiment. Figure 8 This is a schematic diagram of the second-stage heat sink of the high-speed brushless DC planetary geared motor in this embodiment 1; Figure 9 This is a schematic diagram of the housing assembly of the high-speed brushless DC planetary geared motor in this embodiment. Figure 10 This is a schematic diagram of the reduction assembly of the high-speed brushless DC planetary geared motor in this embodiment 1; Figure 11 This is a schematic diagram of the 9-slot 8-pole stator winding structure used in the high-speed brushless DC planetary geared motor of this embodiment 1. Figure 12This is a schematic diagram of the Halbach magnetic field distribution of the high-speed brushless DC planetary geared motor in this embodiment. Figure 13 This is a motor efficiency map of the high-speed brushless DC planetary geared motor in this embodiment 1; Figure 14 This is a schematic diagram of the rotor structure of the high-speed brushless DC planetary geared motor in Embodiment 1 of this invention. Figure 15 This is a schematic diagram of the stator and rotor magnetic pole distribution of the high-speed brushless DC planetary geared motor in this embodiment.

[0020] Illustrations: Housing assembly 100, motor front end cover 200, rotor assembly 300, intermediate shaft 400, clearance space 201, heat dissipation assembly 500, first-stage heat dissipation component 510, second-stage heat dissipation component 520, heat dissipation fins 511, guide vanes 521, curved surface 522, heat dissipation section 101, heat dissipation through hole 1011, spacer 301, inner ring body 512, outer ring body 513, first curved surface 5111, second curved surface 5112, wedge shape Surface 5113, flow guide channel 5114, motor rear end cover 600, air inlet 601, first bearing 602, spring 603, connecting sleeve 523, support rib 524, connecting ring 525, stator assembly 700, PCB board 800, positioning buckle 710, reduction assembly 900, first gear 410, main wheel 910, first inner cavity 911, internal gear part 912, second gear 920, connecting plate 930, output shaft 940. Detailed Implementation

[0021] To make the objectives, features, and advantages of this invention more apparent and understandable, the technical solutions of the embodiments of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the embodiments described below are only some embodiments of this invention, and not all embodiments. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0022] In the description of this invention, it should be understood that the terms "upper," "lower," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the invention 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 the invention. It should be noted that when a component is considered to be "connected" to another component, it can be directly connected to the other component or there may be a component positioned centrally in the connection.

[0023] The technical solution of the present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0024] Example 1: Combination Figures 1 to 15 As shown, an embodiment of the present invention provides a high-speed brushless DC planetary geared motor including a housing assembly 100 and a motor front end cover 200. The housing assembly 100 houses a rotor assembly 300, and an intermediate shaft 400 is rotatably mounted on the motor front end cover 200. A gap space 201 is formed between the rotor assembly 300 and the motor front end cover 200, and a heat dissipation assembly 500 is disposed in the gap space 201.

[0025] It should be noted that, through the above structural arrangement, the rotor assembly 300 can rotate stably around the intermediate shaft 400, thereby achieving high-speed output. A gap space 201 is formed between the rotor assembly 300 and the motor front end cover 200. This gap space 201 not only serves as a flow channel for airflow exchange during high-speed rotor rotation but also provides space for the installation of the heat dissipation assembly 500. Since this gap space 201 is directly located at the intersection of the airflow between the internal heat-generating area of ​​the motor and the external environment, it provides an effective airflow channel foundation for the subsequent multi-stage heat dissipation structure, enabling efficient heat dissipation while ensuring the compactness of the motor structure.

[0026] Combination Figure 2 and Figure 3 As shown, the heat dissipation assembly 500 includes a first-stage heat dissipation component 510 and a second-stage heat dissipation component 520 arranged sequentially along the axial direction of the intermediate shaft 400. The first-stage heat dissipation component 510 is provided with heat dissipation fins 511 radially distributed along the intermediate shaft 400 and having a preset rotation direction to provide the main thrust of airflow.

[0027] Within the aforementioned gap space 201, a first-stage heat sink 510 and a second-stage heat sink 520 are sequentially arranged along the axial direction of the intermediate shaft 400. The first-stage heat sink 510 has heat sink fins 511 radially distributed along the intermediate shaft 400 and having a predetermined rotation direction. These heat sink fins 511 can generate a strong radial airflow thrust when the rotor rotates at high speed, quickly carrying heat from inside the motor to the external flow channel. Through the predetermined rotation direction design, the airflow can be efficiently guided into the second-stage heat sink structure, avoiding a decrease in heat dissipation efficiency caused by disordered airflow diffusion.

[0028] Combination Figure 5 and Figure 6 As shown, the outer periphery of the second-stage heat sink 520 is provided with multiple guide vanes 521. The guide vanes 521 have a curved surface 522 with a preset curvature. The curved surface 522 is used to guide the lateral flow direction of the airflow.

[0029] It should be noted that this design, based on the radial airflow generated by the first-stage heat sink 510, further adjusts the airflow direction, directing it to flow along the outer periphery of the motor and discharge into the heat dissipation channels of the housing. This secondary guided airflow path not only helps to extend the coverage area of ​​the airflow in the high-temperature region, thereby increasing the heat exchange area, but also reduces the turbulence noise caused by the direct impact of airflow on the housing in traditional radial heat dissipation structures. By matching the angle of the curved surface 522 with the external heat dissipation channels, smooth airflow discharge can be achieved, improving overall heat dissipation efficiency and effectively reducing aerodynamic noise while maintaining high-speed operation stability.

[0030] The working principle of this invention is as follows: When the motor is working, the intermediate shaft 400 rotates synchronously with the rotor. The first-stage heat sink 510 first drives the air to generate radial and tangential momentum components on the heat sink fins 511, forming a main airflow with a main thrust along the axial direction and a preset vortex direction. This main airflow enters the gap area near the front cover along the axial direction and reaches the second-stage heat sink 520. The outer peripheral guide vanes 521 of the second-stage heat sink 520 capture and gradually change the flow direction of the main airflow with their arc-shaped curved surfaces, smoothly guiding the originally axial airflow into a lateral / vortex flow, so that the airflow flows along the direction matching the heat sink holes on the side wall of the housing and is discharged through the heat sink holes, thereby realizing the circulation exchange and continuous convective heat transfer of the air inside and outside the motor cavity, while avoiding the generation of strong turbulence and violent wakes. The multi-stage heat dissipation structure of this solution, through the coordinated work of the first stage generating and stabilizing the main airflow and the second stage guiding and changing the flow direction, greatly reduces the generation of airflow convection, significantly improves the heat transfer efficiency, reduces motor noise, and improves motor performance.

[0031] As a preferred embodiment, combined with Figure 1 , Figure 3 and Figure 9 As shown, a heat dissipation part 101 is provided at a preset position in the housing assembly 100, and a second-stage heat dissipation component 520 is disposed on the intermediate shaft 400 near one end of the heat dissipation part 101. The heat dissipation part 101 includes at least one heat dissipation through hole 1011, which extends in a spiral manner along its length direction and has a preset helical angle so that the airflow direction of the curved surface 522 is close to parallel with the length direction of the heat dissipation through hole 1011.

[0032] It should be noted that the spiral angle design makes the airflow direction formed by the curved surface 522 of the guide vane 521 on the second-stage heat sink 520 nearly parallel to the length direction of the heat dissipation through-hole 1011, thereby aligning the airflow direction with the through-hole direction and reducing turbulence losses caused by airflow impact. Compared with conventional straight through-holes, this spiral through-hole structure can effectively reduce noise when airflow passes through the housing while ensuring ventilation volume, and forms a synergistic heat dissipation effect with the first and second-stage heat sinks 520, significantly improving the overall heat dissipation efficiency and operational stability.

[0033] In this embodiment, combined with Figure 2 and Figure 3 As shown, the inner diameter of the rotor assembly 300 is larger than the outer diameter of the intermediate shaft 400, so that a spacer 301 is formed between the rotor assembly 300 and the intermediate shaft 400. The first-stage heat sink 510 is installed in the spacer 301. The first-stage heat sink 510 is connected to the intermediate shaft 400 or is integrally formed with the rotor assembly 300. That is, the first-stage heat sink 510 can be set as a separate part and fixed between the rotor assembly 300 and the intermediate shaft 400 by welding or other connection methods, or it can be integrally formed with the rotor assembly 300. The magnetic ring and the shaft are integrally formed, which reduces the installation steps, reduces the rotor imbalance, and reduces vibration and noise.

[0034] Combination Figure 8 As shown, the first-stage heat sink 510 includes an inner ring body 512 and an outer ring body 513 spaced apart, and heat sink fins 511 are disposed between the inner ring body 512 and the outer ring body 513. The inner ring body 512 is fixedly connected to the intermediate shaft 400, and the outer ring body 513 is fixedly connected to the inner wall of the rotor assembly 300.

[0035] The first-stage heat sink 510 is installed inside the rotor. This installation structure ensures that the first-stage heat sink 510 rotates synchronously with the rotor assembly 300, avoiding additional friction and air resistance caused by relative motion, thereby reducing the generation of additional heat. At the same time, this layout can form a relatively stable and smooth airflow channel inside the rotor center, which helps to quickly guide the heat generated during rotor operation to the gap space 201, and work with the second-stage heat sink 520 to further dissipate heat, achieving a highly efficient heat dissipation effect.

[0036] In this embodiment, combined with Figure 6 and Figure 7As shown, the heat dissipation fin 511 includes a first curved surface 5111 and a second curved surface 5112, which are connected by a wedge-shaped surface 5113. The first curved surface 5111 is a concave curved surface, and the second curved surface 5112 is a convex curved surface. Both the first curved surface 5111 and the second curved surface 5112 extend along the axial direction of the intermediate axis 400. The wedge-shaped surface 5113 gradually narrows from the first curved surface 5111 to the second curved surface 5112 to form a flow channel 5114 inside the heat dissipation fin 511, which is used to guide the airflow along the flow channel 5114.

[0037] It should be noted that the design of the heat dissipation fins 511 combines Bernoulli's principle with the principle of streamlined design. The concave curved surface (first curved surface 5111) provides a relatively large cross-sectional area when the airflow enters, so that the airflow velocity is relatively low and the pressure is relatively high in the initial stage, which helps to stabilize the incoming airflow and reduce the generation of turbulence at the inlet. This acceleration effect not only improves the heat exchange capacity of the airflow, but also promotes the airflow to be discharged more smoothly along the channel direction, reducing turbulent backflow.

[0038] The convex surface (second surface 5112) acts similarly to the diffusion and guiding effect of the trailing edge of an airfoil, causing the streamline to gradually expand outward as the airflow is discharged, reducing the flow resistance at the outlet and reducing noise caused by sudden pressure changes.

[0039] This combination of concave-wedge-convex shape effectively reduces flow separation and keeps the airflow attached to the fin surface, thereby reducing flow resistance and energy loss. At the same time, it avoids the pulsating airflow and high-frequency noise problems that are easily generated by traditional straight or single-curved fins under high-speed rotation.

[0040] In this embodiment, combined with Figure 3 and Figure 5 As shown, a rear end cover 600 of the motor is provided at one end of the housing assembly 100 away from the front end cover 200 of the motor. The rear end cover 600 has several air inlets 601 arranged around the intermediate shaft 400. The air inlets 601 are oriented towards the spacer 301 to form an airflow channel sequentially from the air inlets 601, the spacer 301, to the gap space 201. The intermediate shaft 400 and the rear end cover 600 are connected by a first bearing 602. A spring 603 is provided between the first bearing 602 and the rotor assembly 300. The spring 603 is used to extend the first bearing 602 to provide preload force to the first bearing 602. It should be noted that the two ends of the spring 603 are respectively connected to the inner rotor of the rotor assembly 300 and the first bearing 602, and it rotates synchronously with the intermediate shaft 400 to maintain relative stationary position with the rotor assembly 300 in the direction of rotation.

[0041] It should be noted that, specifically, several air inlets 601 are arranged around the intermediate shaft 400 and facing the spacer 301, allowing external cold air to directly enter the spacer 301 through the air inlets 601 and flow sequentially into the gap space 201, forming a continuous and directional airflow channel. The first bearing 602, located between the intermediate shaft 400 and the motor rear end cover 600, is preloaded by a spring 603. The design of the spring 603 avoids the frictional wear and additional vibrations generated by traditional independent spring structures under high-speed rotation, helping to maintain the stability and low noise characteristics of the bearing during high-speed operation. In addition, the preload of the bearing can effectively suppress axial movement caused by high-speed rotation, thereby improving the reliability and service life of the entire machine.

[0042] In this embodiment, it is specifically described that, in conjunction with Figure 8 As shown, the second-stage heat dissipation component 520 includes a connecting sleeve 523, which is fixedly sleeved on the intermediate shaft 400. The outer side wall of the connecting sleeve 523 is provided with a plurality of support ribs 524 along its circumferential direction, and one end of the support rib 524 is connected to a connecting ring 525. Among them, the guide vanes 521 are evenly arranged on the connecting ring 525, and the guide vanes 521 extend along the axial direction of the intermediate shaft 400. The curved surface 522 extends obliquely from one end of the guide vane 521 to form a spiral air guiding structure around the intermediate shaft 400.

[0043] It should be noted that the support rib 524 not only serves to fix and support the guide vane 521, but also acts as a mechanical support in the overall structure. The dimensions of the support rib 524 are optimized to ensure sufficient structural rigidity, preventing the guide vane 521 from shaking or swaying under high-speed rotation, and to avoid airflow obstruction caused by an excessively large cross-section, thereby reducing wind resistance. The guide vanes 521, which are evenly arranged on the connecting ring 525, extend axially along the intermediate axis 400. Their curved surfaces 522 extend at a certain angle to form a spiral air-guiding structure around the intermediate axis 400. This structure can actively guide the airflow along the spiral path during rotation, increase the axial component of the airflow, effectively improve the airflow speed and heat exchange effect, while maintaining the stability of the airflow and reducing the generation of turbulence and additional noise.

[0044] In this embodiment, combined with Figure 2 and Figure 4 As shown, the motor also includes a stator assembly 700 and a PCB board 800 disposed at one end of the stator assembly 700. A hollow groove is provided at a preset position on the PCB board 800 to form a groove that runs through the airflow channel.

[0045] A positioning buckle 710 is provided on the outer side wall of the stator assembly 700, and a slot is provided on the housing assembly 100 to engage with the positioning buckle 710. The positioning buckle 710 cooperates with the slot to achieve a fixed connection between the stator assembly 700 and the housing assembly 100.

[0046] Combination Figure 11 and Figure 12 As shown, this motor further adopts a 9-slot, 8-pole brushless DC motor design, featuring a fractional-slot concentrated winding structure. This results in short winding ends, high efficiency, high power density, a winding factor of 0.945, and high winding utilization. (See efficiency map). Figure 13 Analysis shows that the motor has high efficiency across a wide speed range and is suitable for applications requiring high speed and high torque output.

[0047] In addition, combined Figure 14 and Figure 15 As shown, the rotor employs a Halbach magnetic ring structure, utilizing a magnetic field focusing effect to enhance the magnetic field on one side and weaken it on the other, creating a near-ideal unilateral magnetic field. This design not only improves the operating point of the permanent magnet and the magnetic energy conversion efficiency but also achieves a near-sinusoidal air gap magnetic field, reducing harmonic losses and significantly lowering high-frequency electromagnetic noise. The rotor uses a non-ferrous core material, further reducing rotational inertia and improving dynamic response performance.

[0048] The rotor structure adopts an integrated molding design, with the magnetic ring and shaft integrally formed, resulting in low rotor imbalance, vibration, and noise. Fan guide vanes are integrated at the rotor end to enhance the overall heat dissipation capacity.

[0049] In terms of control, the motor has three built-in Hall effect sensors that sense the real-time position of the rotor's magnetic poles. Combined with a sensor-based control algorithm, this enables efficient and high-torque output over a wide speed range. The built-in Hall effect sensor design effectively shortens the motor's axial length and increases power density.

[0050] The aforementioned electromagnetic and structural design features work in conjunction with the multi-stage heat dissipation structure described in this invention to achieve high-efficiency, low-temperature rise, and low-noise operation of the motor.

[0051] In this embodiment, combined with Figure 10 As shown, the motor also includes a reduction assembly 900 disposed on the front end cover 200 of the motor, and a first gear 410 disposed at one end of the intermediate shaft 400; the reduction assembly 900 includes a main wheel 910, the main wheel 910 is provided with a first inner cavity 911, an internal gear part 912 is provided on the side wall of the first inner cavity 911, the internal gear part 912 meshes with a plurality of second gears 920, and the plurality of second gears 920 respectively mesh with the first gear 410; a connecting plate 930 is rotatably connected to the first inner cavity 911, the plurality of second gears 920 are respectively mounted on the connecting plate 930, and the connecting plate 930 is provided with an output shaft 940 for power output.

[0052] The reduction gear assembly 900 is integrated into the front cover 200 of the motor, achieving power reduction and transmission through the meshing of the first gear 410 and multiple second gears 920. An internal gear section 912 on the side wall of the first inner cavity 911 of the main body wheel 910 meshes with multiple evenly distributed second gears 920. These second gears 920 simultaneously mesh with the first gear 410 on the intermediate shaft 400, forming a planetary gear transmission structure. The connecting plate 930 is rotatably connected to the first inner cavity 911 and serves as a mounting base for the multiple second gears 920, while also outputting power to the output shaft 940. This structure achieves a large transmission ratio while ensuring transmission efficiency, effectively reducing output speed and increasing torque to meet the application requirements of low-speed, high-torque operation, while maintaining a compact front-end structure layout, contributing to the miniaturization and high efficiency of the entire machine.

[0053] Example 2: This invention also provides an optimized design method for a high-speed brushless DC planetary geared motor, applicable to the design of a high-speed brushless DC planetary geared motor as described in Example 1. The optimized design method includes the following steps: S1, construct a parameterized model of the motor, define a set of adjustable variables and set the engineering constraint range of each adjustable variable; the set of adjustable variables includes the helix angle α and radial height H1 of the heat dissipation fins 511 of the first-stage heat dissipation component 510, the radius of curvature R of the guide vanes 521 of the second-stage heat dissipation component 520, the helix angle γ of the heat dissipation through hole 1011 and the width W of the spacer 301.

[0054] Among them, the engineering constraints are set based on: mechanical strength limits (such as the minimum thickness of the 511 heat sink fins to prevent breakage); and aerodynamic performance boundaries (such as excessive rotation angle leading to airflow separation). Assembly feasibility (e.g., the width of the 301 gap needs to accommodate bearing tolerances).

[0055] S2, sample the parameterized model of the motor to generate a sample set, perform automated CFD simulation on each sample, calculate the heat dissipation efficiency η and noise level dB of the airflow channel (inlet 601 → spacer 301 → first-stage heat sink 510 → second-stage heat sink 520 → heat dissipation through hole 1011), and output a simulation database containing variable parameters and performance response.

[0056] Automated CFD simulation focuses on the physical processes of the airflow channel (inlet 601 → spacer 301 → heat dissipation fins 511 → guide vanes 521 → heat dissipation through-holes 1011): Heat dissipation efficiency η: Calculated based on airflow Q and pressure drop ΔP (η=Q / ΔP), reflecting the heat dissipation energy consumption ratio; Noise level dB: obtained by A-weighted integration of the pressure pulsation spectrum on the surface of guide vane 521, characterizing aerodynamic noise.

[0057] For each sample design, the heat dissipation efficiency η and noise level dB in the airflow channel are calculated using automated CFD (Computational Fluid Dynamics) simulation, and the variable parameters and corresponding performance response values ​​are stored in the simulation database. This process can evaluate the influence trend of different structural parameters on heat dissipation and noise in advance without physical prototype manufacturing.

[0058] S3, based on a simulation database, trains a Gaussian process regression surrogate model to predict heat dissipation efficiency η and noise level dB. Sensitivity analysis identifies key parameters affecting η and dB, and generates a priority list of these key parameters (which are generated from the set of adjustable variables). This effectively narrows the range of optimization variables, focusing design optimization on the parameters that contribute most to performance improvement, thus increasing optimization efficiency while avoiding interference from invalid parameters.

[0059] The Gaussian process regression (GP) model was used to predict η and dB, and its advantages are: High-precision fitting of nonlinear responses with small sample sizes; outputting quantified values ​​of prediction uncertainty to guide active learning.

[0060] Sensitivity analysis (using the Sobol index method) identifies the priority of key parameters, such as: The heat dissipation efficiency η is mainly affected by the rotation angle α and the width W of the spacer 301 (the rotation angle controls the airflow angle of attack, and the width determines the flow rate); the noise dB is sensitive to the curvature radius R of the guide vane 521 (abrupt curvature causes vortex shedding noise).

[0061] S4 uses key parameters as optimization variables, with the objectives of maximizing heat dissipation efficiency η and minimizing noise level dB, searches for the optimal solution set, performs thermal coupling simulation to verify the optimal solution set, and outputs a set of corrected candidate parameter schemes.

[0062] After obtaining the key optimization variables, they are input as design variables into a multi-objective optimization algorithm. With the optimization objectives of "improving heat dissipation efficiency and reducing noise levels," a set of optimal solutions is obtained. For these optimal solutions, thermal coupling simulations are performed again to verify their performance stability under actual heat flow and structural interaction conditions.

[0063] It should be noted that the simulation verification mechanism only performs transient thermo-acoustic coupling simulation on potential solutions (such as η>10% of the baseline value) to avoid full calculation; the parameter adaptive correction dynamically compensates for the errors of the simulation and surrogate model (such as the α compensation angle being linearly related to the η error).

[0064] S5, introduce manufacturing tolerance variables into the candidate parameter scheme set to simulate actual working conditions, and screen those that satisfy the temperature rise ΔT ≤ ΔT max And the noise dB≤dB max The target solution is to output engineering parameter tables and tolerance control specifications.

[0065] Manufacturing tolerance variables are introduced for robustness assessment, simulating the impact of deviations that may occur during actual production and assembly on performance. Target solutions are selected that simultaneously satisfy the conditions that the temperature rise ΔT does not exceed the set maximum allowable value ΔTmax and the noise level does not exceed the set upper limit dBmax.

[0066] In this embodiment, step S2 specifically includes the following steps: S21, generate M sample points within the defined engineering constraints, each sample point containing a preset logical combination of the adjustable variable set, and output the sample set of adjustable parameters.

[0067] Each sample point contains a logical combination of adjustable variables (α, H1, R, γ, W) to ensure uniform coverage of the parameter space; the sample size M is dynamically adjusted according to the design complexity to balance computational cost and model requirements. The output sample set provides a systematic input for subsequent simulations, covering various possibilities in the design space and providing representative and comparable structural schemes for subsequent simulation analysis.

[0068] S22, based on the sample set, generate the corresponding geometric models of the first-level heat sink 510, the second-level heat sink 520 and the heat dissipation through hole 1011 in batches in the simulation software, and implement boundary layer densification in the gap space 201, the heat dissipation fin 511 flow channel 5114 and the curved surface 522 area through the mesh generation tool, and output a standardized mesh file set.

[0069] Based on the generated sample set, three-dimensional geometric models of the first-stage heat sink 510, the second-stage heat sink 520, and the heat dissipation through-holes 1011 were created in batches using simulation software. To ensure the accuracy of the simulation results, a script-controlled mesh generation tool was used to implement boundary layer refinement in regions with significant flow and heat transfer characteristics, such as the gap space 201, the flow channel 5114 of the heat sink fins 511, and the curved surface 522 of the flow guide fins 521, thereby improving the ability to capture flow separation phenomena. Adaptive coarse meshes were used in other regions to optimize computational efficiency and output a standardized mesh file set to ensure the geometric consistency of the simulation model.

[0070] S23, calls the CFD solver to perform automated simulation on the mesh file set, specifically: Define the boundary conditions of the airflow channel, including setting the air inlet 601 as a pressure inlet (ambient pressure) and the heat dissipation through-hole 1011 as a pressure outlet (back pressure value). Calculate the flow path of airflow through inlet 601 → spacer 301 → heat dissipation fins 511 → guide channel 5114 → guide plate 521 curved surface 522 → heat dissipation through hole 1011. Simultaneously solve the convection heat transfer equation and output the heat dissipation efficiency η=Q / ΔP, where Q is the air flow rate and ΔP is the pressure drop; The noise level dB=10log is calculated based on the blade passage frequency noise model. 10 (P 2 / P0 2 P is the surface pressure amplitude of the guide vane 521.

[0071] It enables simultaneous evaluation of aerodynamic and acoustic performance, providing a reliable basis for the comprehensive optimization of multiple performance indicators.

[0072] S24, extract key response data from the simulation results, associate the key response data with the corresponding sample set, and generate a simulation database according to preset fields; the key response data includes heat dissipation efficiency η, noise level dB, flow velocity Vw of the interval 301 and flow velocity Vout of the heat dissipation through hole 1011.

[0073] A simulation database is generated by pre-defined field structures, enabling the performance results of different schemes to be systematically stored and retrieved.

[0074] The above-described embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. 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. Such 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 high-speed brushless DC planetary geared motor, characterized in that, It includes a housing assembly (100) and a motor front cover (200), wherein a rotor assembly (300) is housed inside the housing assembly (100), and an intermediate shaft (400) is rotatably mounted on the motor front cover (200). A gap space (201) is formed between the rotor assembly (300) and the front end cover (200) of the motor, and a heat dissipation assembly (500) is provided in the gap space (201). The heat dissipation assembly (500) includes a first-stage heat dissipation component (510) and a second-stage heat dissipation component (520) arranged sequentially along the axial direction of the intermediate shaft (400). The first-stage heat dissipation component (510) is provided with heat dissipation fins (511) that are radially distributed along the intermediate shaft (400) and have a preset rotation direction, so as to provide the main thrust of airflow. The outer periphery of the second-stage heat sink (520) is provided with a plurality of guide vanes (521), the guide vanes (521) having a curved surface (522) with a preset curvature, the curved surface (522) being used to guide the lateral flow direction of the airflow.

2. The high-speed brushless DC planetary geared motor according to claim 1, characterized in that, The housing assembly (100) has a heat dissipation part (101) at a preset position, and the second-stage heat dissipation component (520) is disposed on the intermediate shaft (400) at one end near the heat dissipation part (101); The heat dissipation part (101) includes at least one heat dissipation through hole (1011), the heat dissipation through hole (1011) extends in a spiral manner along its length direction, and the heat dissipation through hole (1011) has a preset spiral angle so that the flow direction of the curved surface (522) is close to parallel to the length direction of the heat dissipation through hole (1011).

3. The high-speed brushless DC planetary geared motor according to claim 1, characterized in that, The inner diameter of the rotor assembly (300) is larger than the outer diameter of the intermediate shaft (400) so that a spacer (301) is formed between the rotor assembly (300) and the intermediate shaft (400), and the first-stage heat sink (510) is installed in the spacer (301); wherein the first-stage heat sink (510) is connected to the intermediate shaft (400) or is integrally formed with the rotor assembly (300).

4. The high-speed brushless DC planetary geared motor according to claim 3, characterized in that, The first-stage heat sink (510) includes an inner ring body (512) and an outer ring body (513) spaced apart. The heat sink fins (511) are disposed between the inner ring body (512) and the outer ring body (513). The inner ring body (512) is fixedly connected to the intermediate shaft (400), and the outer ring body (513) is fixedly connected to the inner wall of the rotor assembly (300).

5. The high-speed brushless DC planetary geared motor according to claim 4, characterized in that, The heat dissipation fins (511) include a first curved surface (5111) and a second curved surface (5112), and the first curved surface (5111) and the second curved surface (5112) are connected by a wedge-shaped surface (5113); The first curved surface (5111) is a concave curved surface, and the second curved surface (5112) is a convex curved surface. Both the first curved surface (5111) and the second curved surface (5112) extend along the axial direction of the intermediate axis (400). The wedge-shaped surface (5113) gradually narrows from the first curved surface (5111) to the second curved surface (5112) to form a flow channel (5114) inside the heat dissipation fins (511) to guide the airflow along the flow channel (5114).

6. The high-speed brushless DC planetary geared motor according to claim 4, characterized in that, The housing assembly (100) is provided with a motor rear end cover (600) at one end away from the motor front end cover (200). The motor rear end cover (600) is provided with a plurality of air inlets (601), and the plurality of air inlets (601) are arranged around the intermediate shaft (400). The air inlet (601) is disposed toward the spacer (301) to form an airflow channel from the air inlet (601), the spacer (301) to the gap space (201) in sequence.

7. The high-speed brushless DC planetary geared motor according to claim 6, characterized in that, The intermediate shaft (400) is connected to the motor rear end cover (600) via a first bearing (602). A spring (603) is provided between the first bearing (602) and the rotor assembly (300). The spring (603) is used to extend the first bearing (602) to provide preload to the first bearing (602).

8. The high-speed brushless DC planetary geared motor according to claim 1, characterized in that, The second-stage heat sink (520) includes a connecting sleeve (523), which is fixedly sleeved on the intermediate shaft (400). The outer side wall of the connecting sleeve (523) is provided with a plurality of support ribs (524) along its circumferential direction, and one end of the support rib (524) is connected to a connecting ring (525). The guide vanes (521) are uniformly disposed on the connecting ring (525), and the guide vanes (521) extend along the axial direction of the intermediate shaft (400). The curved surface (522) extends obliquely from one end of the guide vanes (521) to form a spiral air guiding structure around the intermediate shaft (400).

9. The high-speed brushless DC planetary geared motor according to claim 1, characterized in that, It also includes a stator assembly (700) and a PCB board (800) disposed at one end of the stator assembly (700), wherein a hollow groove is provided at a preset position of the PCB board (800); The stator assembly (700) has a positioning buckle (710) on its outer side wall, and the housing assembly (100) has a slot that engages with the positioning buckle (710). The positioning buckle (710) cooperates with the slot to achieve a fixed connection between the stator assembly (700) and the housing assembly (100).

10. The high-speed brushless DC planetary geared motor according to claim 1, characterized in that, It also includes a reduction gear assembly (900) disposed on the front end cover (200) of the motor, and a first gear (410) is disposed at one end of the intermediate shaft (400). The deceleration assembly (900) includes a main wheel (910), the main wheel (910) is provided with a first inner cavity (911), an internal gear part (912) is provided on the side wall of the first inner cavity (911), the internal gear part (912) is meshed with a plurality of second gears (920), and the plurality of second gears (920) respectively mesh with the first gear (410); The first inner cavity (911) is rotatably connected to a connecting plate (930), and a plurality of second gears (920) are respectively installed on the connecting plate (930). The connecting plate (930) is provided with an output shaft (940) for power output.

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