Brushless direct current motor

Abstract

The invention relates to the technical field of motors, in particular to a brushless direct current motor which comprises a machine shell, a tire is fixedly connected to the outer surface of the machine shell, a rotating shaft is installed on the surface of the tire, a magnet fixing frame is arranged in the machine shell, and a magnet is fixedly connected to the surface of the magnet fixing frame. The steel sleeve and the insulating framework are integrally formed, the machining precision and the structural stability of the steel sleeve are guaranteed, the concentricity of the first bearing and the second bearing during installation is guaranteed, noise caused by installation deflection is reduced, meanwhile, the containing cavity for fixing the bearing seat is formed in the insulating framework, the steel sleeve is embedded into the containing cavity, and therefore the bearing seat can be fixed conveniently. The installation precision and stability of the first bearing and the second bearing are improved, meanwhile, the isolation gasket is arranged between the first bearing and the second bearing, mutual interference between the first bearing and the second bearing is prevented, and noise is reduced.

Description

Technical Field

[0001] This invention relates to the field of motor technology, specifically to a brushless DC motor. Background Technology

[0002] Small or micro motors, such as a permanent magnet brushless DC motor, have a series of advantages such as high power density, small geometric size, fast dynamic response and high operating efficiency. They have broad application prospects in mobile applications, such as the use of a permanent magnet brushless motor in wheel hubs.

[0003] In operation, hub brushless DC motors require higher precision in component installation. Existing hub brushless DC motors are usually designed with bearings in two separate cavities, resulting in low installation precision. This leads to bearing clearance after installation, and large clearance causes eccentricity during motor operation, resulting in noise resonance and other problems. Furthermore, the motor's waterproof performance is insufficient when operating in humid environments, which can easily lead to water ingress and short circuits. Summary of the Invention

[0004] The purpose of this invention is to provide a brushless DC motor to solve the problems mentioned in the background art, such as excessive bearing clearance causing eccentricity and noise resonance during motor operation, and insufficient waterproof performance when the motor is running in a humid environment, which can easily lead to water ingress and short circuits.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a brushless DC motor comprising a housing, a tire fixedly connected to the outer surface of the housing, a rotating shaft mounted on the surface of the tire, a magnet mounting bracket disposed inside the housing, a magnet fixedly connected to the surface of the magnet mounting bracket, a magnetic ring disposed inside the magnet mounting bracket, a PCBA disposed inside the housing, an insulating frame fixedly connected inside the housing, a stator core fixedly connected to the surface of the insulating frame, a coil wound around the surface of the stator core, a steel sleeve fixedly connected to the surface of the insulating frame, a first bearing disposed inside the steel sleeve, a second bearing disposed inside the steel sleeve, an isolation washer disposed between the first and second bearings, a nut washer disposed on the top of the steel sleeve, a nut threadedly connected to the top of the rotating shaft, a first sealing ring disposed inside the housing, a sealing cap covering the top of the first sealing ring, a second sealing ring disposed outside the housing, a side cover disposed on the side of the housing, and lead wires disposed on the surface of the housing.

[0006] Preferably, the insulating frame is integrally formed with the stator core.

[0007] Preferably, the insulating frame is provided with a cavity for fixing the bearing seat, and the cavity has a built-in steel sleeve.

[0008] Preferably, the steel sleeve is integrally formed, and the first bearing and the second bearing are concentric.

[0009] Preferably, the tire has several stripes evenly distributed and arranged in a staggered manner on its outer perimeter.

[0010] Preferably, the side cover and the housing are positioned and fixed by a number of fasteners 20-1.

[0011] Preferably, the first sealing ring and the second sealing ring are placed at a 90-degree angle to form an L-shaped waterproof structure.

[0012] Compared with the prior art, the beneficial effects of the present invention are:

[0013] 1. This brushless DC motor is integrally formed with a steel sleeve and an insulating frame, ensuring the machining accuracy and structural stability of the steel sleeve. This guarantees the concentricity of the first and second bearings during installation, reducing noise caused by installation misalignment. At the same time, a cavity for fixing the bearing seat is set on the insulating frame, and the steel sleeve is embedded in the cavity, improving the installation accuracy and stability of the first and second bearings. In addition, an isolation washer is set between the first and second bearings to prevent mutual interference between them and reduce noise generation.

[0014] 2. The brushless DC motor forms an L-shaped waterproof structure by placing the first sealing ring and the sealing cover at a 90-degree angle, which ensures the comprehensiveness and reliability of the seal. When the rotor sub-assembly is running, the first sealing ring and the second sealing ring can form a dynamic waterproof barrier to prevent water from entering the motor from the side and avoid short circuits and malfunctions. Attached Figure Description

[0015] Figure 1 This is a frontal three-dimensional exploded view of the structure of the present invention;

[0016] Figure 2 This is a front sectional view of the structure of the present invention;

[0017] Figure 3 This is a side sectional view of the structure of the present invention;

[0018] Figure 4 For the present invention Figure 3 Enlarged structural diagram at point K;

[0019] Figure 5 For the present invention Figure 3 Enlarged structural diagram at point J;

[0020] Figure 6 For the present invention Figure 3 Enlarged structural diagram at point L;

[0021] Figure 7This is a partial cross-sectional view of the structure of the present invention.

[0022] Figure 8 For the present invention Figure 7 A magnified structural diagram at point F in the middle.

[0023] In the diagram: 1. Shaft; 2. Tire; 3. Housing; 4. Magnet holder; 5. Magnet; 6. Magnetic ring; 7. PCBA; 8. Stator core; 9. Insulating frame; 10. Coil; 11. Steel sleeve; 12. First bearing; 13. Isolation washer; 14. Second bearing; 15. Nut washer; 16. Nut; 17. First sealing ring; 18. Sealing cover; 19. Second sealing ring; 20. Side cover; 21. Lead wire assembly. Detailed Implementation

[0024] 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, and 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.

[0025] Please see Figure 1-8 One embodiment provided by the present invention:

[0026] A brushless DC motor includes a housing 3, a tire 2 fixedly connected to the outer surface of the housing 3, a shaft 1 mounted on the surface of the tire 2, a magnet mounting bracket 4 inside the housing 3, and a magnet 5 fixedly connected to the surface of the magnet mounting bracket 4. The magnet 5 uses high-performance rare-earth permanent magnet material, improving the magnetic performance and efficiency of the motor. A magnetic ring 6 is provided inside the magnet mounting bracket 4. A PCBA 7 is installed inside the housing 3, and the PCBA 7 is equipped with an overcurrent protection circuit. When the motor current exceeds a set value, the power supply is automatically cut off to prevent the motor from overheating and being damaged. An insulating frame 9 is fixedly connected inside the housing 3, a stator core 8 is fixedly connected to the surface of the insulating frame 9, and a coil 10 is wound around the surface of the stator core 8. A steel sleeve 11 is fixedly connected, and a first bearing 12 and a second bearing 14 are installed inside the steel sleeve 11. An isolation washer 13 is provided between the first bearing 12 and the second bearing 14. A nut washer 15 is provided on the top of the steel sleeve 11. A nut 16 is threadedly connected to the top of the rotating shaft 1. A first sealing ring 17 is provided inside the housing 3. A sealing cover 18 is provided on the top of the first sealing ring 17. A second sealing ring 19 is provided on the outside of the housing 3. A side cover 20 is installed on the side of the housing 3. A lead wire 21 is provided on the surface of the housing 3. The lead wire 21 is used to connect to a power supply or an external circuit. The lead wire 21 adopts a double-layer insulation design, with the outer layer being high-temperature resistant silicone and the inner layer being high-strength fiber, to ensure the durability and safety of the lead wire.

[0027] Furthermore, the insulating frame 9 is integrally formed with the stator core 8, which improves the structural stability of the motor.

[0028] Furthermore, the insulating frame 9 is provided with a cavity for fixing the bearing seat, and the cavity has a built-in steel sleeve, which improves the installation accuracy and stability of the first bearing 12 and the second bearing 14.

[0029] Furthermore, the steel sleeve 11 is integrally machined, and the first bearing 12 and the second bearing 14 are concentric, which reduces the noise caused by installation misalignment.

[0030] Furthermore, the tire 2 has several staggered stripes evenly distributed around its periphery, which increases the tire 2's movement stability.

[0031] Furthermore, the side cover 20 and the housing 3 are positioned and fixed by a number of fasteners 20-1, which improves the stability of the structure. The fasteners of the side cover 20-1 adopt a snap-on design, and each fastener is provided with an elastic snap to ensure that the connection between the side cover 20 and the housing 3 is more secure and not easy to loosen.

[0032] Furthermore, the first sealing ring 17 and the second sealing ring 19 are placed at a 90-degree angle to form an L-shaped waterproof structure, which plays a dynamic waterproof role when the rotor assembly is running, effectively preventing water from entering the motor. The first sealing ring 17 and the second sealing ring 19 are made of high-temperature resistant and wear-resistant rubber materials to ensure that they can maintain good sealing performance under high temperature and long-term operation conditions.

[0033] Working principle: The steel sleeve 11 and the insulating frame 9 are integrally formed, ensuring the processing accuracy and structural stability of the steel sleeve 11, guaranteeing the concentricity of the first bearing 12 and the second bearing 14 during installation, and reducing noise caused by installation misalignment. At the same time, a cavity for fixing the bearing seat is set on the insulating frame 9, and the steel sleeve 11 is embedded in the cavity, which improves the installation accuracy and stability of the first bearing 12 and the second bearing 14. Meanwhile, an isolation washer 13 is set between the first bearing 12 and the second bearing 14 to prevent mutual interference between the first bearing 12 and the second bearing 14 and reduce noise generation.

[0034] The first sealing ring 17 and the sealing cover 18 are placed at a 90-degree angle to form an L-shaped waterproof structure, which ensures the comprehensiveness and reliability of the seal. When the rotor sub-assembly is running, the first sealing ring 17 and the second sealing ring 19 can form a dynamic waterproof barrier to prevent water from entering the motor from the side and avoid short circuits and malfunctions.

[0035] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

Claims

1. A brushless DC motor, characterized in that: The system includes a housing (3), on the outer surface of which a tire (2) is fixedly connected, and a rotating shaft (1) is mounted on the surface of the tire (2). Inside the housing (3) is a magnet mounting bracket (4), on the surface of which a magnet (5) is fixedly connected, and inside the magnet mounting bracket (4) is a magnetic ring (6). Inside the housing (3) is a PCBA (7), and inside the housing (3) is an insulating frame (9). On the surface of the insulating frame (9) is a stator core (8), and on the surface of the stator core (8) are wound coils (10). On the surface of the insulating frame (9) is a steel sleeve (11). The steel sleeve (11) is equipped with a first bearing (12) and a second bearing (14). An isolation washer (13) is provided between the first bearing (12) and the second bearing (14). A nut washer (15) is provided on the top of the steel sleeve (11). A nut (16) is threadedly connected to the top of the rotating shaft (1). A first sealing ring (17) is provided inside the housing (3). A sealing cover (18) is provided on the top of the first sealing ring (17). A second sealing ring (19) is provided on the outside of the housing (3). A side cover (20) is installed on the side of the housing (3). A lead wire (21) is provided on the surface of the housing (3).

2. The brushless DC motor according to claim 1, characterized in that: The insulating frame (9) is integrally formed with the stator core (8).

3. The brushless DC motor according to claim 1, characterized in that: The insulating frame (9) is provided with a cavity for fixing the bearing seat, and a steel sleeve is placed inside the cavity.

4. A brushless DC motor according to claim 1, characterized in that: The steel sleeve (11) is integrally formed, and the first bearing (12) and the second bearing (14) are concentric.

5. A brushless DC motor according to claim 1, characterized in that: The tire (2) has several stripes evenly distributed and arranged around its periphery.

6. A brushless DC motor according to claim 1, characterized in that: The side cover (20) and the housing (3) are positioned and fixed by a number of fasteners 20-1.

7. A brushless DC motor according to claim 6, characterized in that: The first sealing ring (17) and the second sealing ring (19) are placed at a 90-degree angle to form an L-shaped waterproof structure.

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