Mechanical seal device, outer rotor brushless DC motor, wheel hub motor

Abstract

This invention provides a mechanical sealing device, an external rotor brushless DC motor, and a hub motor, including a first sealing ring, a second sealing ring, and an elastic support assembly fitted onto the motor shaft. A first sealing ring is fitted around the outer circumference of the first sealing ring, with its outer ring interfering with the inner wall of an end cover and its inner ring interfering with the outer side of the first sealing ring, thus sealing the first sealing ring and the end cover. A second sealing ring is fitted around the outer circumference of the second sealing ring and is also fitted onto the motor shaft, with its inner ring interfering with both the second sealing ring and the motor shaft, thus sealing the second sealing ring and the motor shaft. The elastic support assembly is in a compressed state, with one end connected to the second sealing ring. Through elastic force, it presses the second sealing ring against the first sealing ring, sealing the contact surfaces of the second and first sealing rings. This invention has a robust structure, strong sealing performance, and can adapt to various media and operating conditions, improving the sealing performance and service life of the motor.

Description

Technical Field

[0001] This utility model relates to the field of motor technology, specifically to a mechanical sealing device, an external rotor brushless DC motor, and a hub motor. Background Technology

[0002] External rotor brushless DC motors control the current direction via an electronic commutator. As the external rotor rotates, the magnetic field changes accordingly. The electronic commutator controls the current based on this magnetic field change, ensuring the armature on the armature shaft remains in a rotating state. Because of the magnetic force between the armature on the armature shaft and the external rotor, the armature drives the external rotor to rotate together. External rotor brushless DC motors are widely used in the electric two-wheeled bicycle industry due to their advantages such as high efficiency, energy saving, and low noise.

[0003] However, due to the complex operating environment of motors, including factors such as particulate matter, humidity, temperature fluctuations, and ultraviolet radiation, the internal sealing of motors has always been a technical challenge. Traditional sealing methods include oil seals. During operation, the sealing performance deteriorates due to aging and wear of the oil seal lip, as well as aging and failure due to ultraviolet radiation. This leads to internal media leakage, shortened service life, and other defects, failing to meet the high performance requirements of the public for motors. Utility Model Content

[0004] In view of the deficiencies in the prior art, the purpose of this utility model is to provide a mechanical sealing device, an external rotor brushless DC motor, and a hub motor.

[0005] According to the present invention, a mechanical sealing device is provided for sealing the gap between the motor shaft and the motor end cover;

[0006] The mechanical seal device includes a first sealing ring, a second sealing ring, and an elastic support assembly sleeved on the motor shaft;

[0007] A first sealing ring is fitted around the outer periphery of the first sealing ring. The outer ring of the first sealing ring is press-fitted with the inner wall of the end cap, and the inner ring of the first sealing ring is press-fitted with the outer side of the first sealing ring, so that the first sealing ring and the end cap are sealed.

[0008] The outer circumference of the second sealing ring is fitted with a second sealing ring, which is also fitted on the motor shaft. The inner ring of the second sealing ring is interference-fitted with the second sealing ring and the motor shaft respectively, so that the second sealing ring and the motor shaft are sealed.

[0009] The elastic support component is in a compressed state, with one end connected to the second sealing ring. The elastic force presses the second sealing ring against the first sealing ring, thereby sealing the contact surfaces of the second sealing ring and the first sealing ring.

[0010] Furthermore, the elastic support assembly includes: a second sealing ring support, a spring, and a spring base sleeved on the motor shaft;

[0011] The second sealing ring support is connected to the outer periphery of the second sealing ring, and one end of the spring is connected to the second sealing ring support and the other end is connected to the spring base.

[0012] Furthermore, a bearing is connected between the motor shaft and the end cover, and the spring base abuts against one side of the bearing.

[0013] Furthermore, the spring base and the end cap are interference-fitted, fastened with screws, or secured with glue.

[0014] Furthermore, the spring is made of spring steel.

[0015] Furthermore, the spring is fixedly connected to the spring base.

[0016] Furthermore, the first sealing ring and the second sealing ring are made of elastic material;

[0017] The first sealing ring is made of silicon carbide or ceramic;

[0018] The second sealing ring is made of resin-impregnated graphite or bronze.

[0019] Furthermore, the roughness of the contact surfaces of both the second sealing ring and the first sealing ring is ≤Ra0.8.

[0020] The present invention provides an external rotor brushless DC motor, including the aforementioned mechanical seal device.

[0021] According to the present invention, a hub motor includes the aforementioned external rotor brushless DC motor.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] This invention achieves effective sealing of the gap between the motor shaft and the housing through the design of sealing rings and sealing rings, reducing leakage and improving the operating efficiency of the motor.

[0024] The mechanical seal device of this invention is made of wear-resistant and corrosion-resistant materials, which can adapt to various media and working conditions and improve the service life of the motor. Attached Figure Description

[0025] Other features, objects, and advantages of this invention will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings:

[0026] Figure 1 This is a schematic diagram of the structure of this utility model;

[0027] Figure 2 This is a schematic diagram of the actual structure of this utility model;

[0028] Figure 3 This is a schematic diagram of the structure of the first sealing ring of the component of this utility model;

[0029] Figure 4 This is a schematic diagram of the structure of the second sealing ring of the component of this utility model;

[0030] Figure 5 This is a schematic diagram of the spring structure of the component of this utility model. Detailed Implementation

[0031] The present invention will now be described in detail with reference to specific embodiments. These embodiments will help those skilled in the art to further understand the present invention, but do not limit the present invention in any way. It should be noted that those skilled in the art can make several changes and improvements without departing from the concept of the present invention. These all fall within the protection scope of the present invention.

[0032] like Figure 1 As shown, a mechanical seal device is used to seal the gap between the motor shaft 1 and the motor end cover 2. The mechanical seal device is positioned on the motor as follows. Figure 2 As shown, the end caps 2 are located at the junction of motor shaft 1 and both sides of the motor. Figure 2 Only one side is shown.

[0033] The mechanical seal device includes: a first sealing ring 3, a first sealing ring 4, a second sealing ring 5, a second sealing ring 6, and an elastic support assembly. The first sealing ring 4, the second sealing ring 5, and the elastic support assembly are fitted onto the motor shaft 1. The first sealing ring 3 is fitted around the outer circumference of the first sealing ring 4, with its outer ring interfering with the inner wall of the end cover 2, and its inner ring interfering with the outer side of the first sealing ring 4, thus sealing the first sealing ring 4 with the end cover 2. The second sealing ring 6 is fitted around the outer circumference of the second sealing ring 5 and is also fitted onto the motor shaft 1. Its inner ring interfering with both the second sealing ring 5 and the motor shaft 1, thus sealing the second sealing ring 5 with the motor shaft 1. The elastic support assembly is in a compressed state, with one end connected to the second sealing ring 6. Through its elasticity, it presses the second sealing ring 5 against the first sealing ring 4, ensuring a tight seal between the contact surfaces of the second sealing ring 5 and the first sealing ring 4. Thus, the three sealing structures effectively seal the gap between the motor shaft 1 and the motor end cover 2, and the sealing structure is reliable.

[0034] It should be noted that in this embodiment, the motor is an external rotor motor, meaning the motor shaft 1 is a relatively stationary component, while the end cover 2 is connected to the rotor, making the end cover 2 a rotating component. Since the first sealing ring 4 and the first sealing ring 3 are interference-fitted with the end cover 2, they will rotate with the end cover 2, hence they are called "moving rings". Because the motor shaft 1 is a relatively stationary component, the interference-fitted second sealing ring 6 and the second sealing ring 5 will not rotate with the motor shaft 1, hence they are called "stationary rings". However, those skilled in the art know that if the motor is replaced with an internal rotor motor, the moving ring will become the stationary ring, and vice versa.

[0035] In this embodiment, the first sealing ring 3 and the second sealing ring 6 are made of elastic materials, such as rubber or silicone, to ensure a tight fit with the sealing ring and the fixing seat. The rotating first sealing ring 4 is made of wear-resistant and corrosion-resistant materials, such as silicon carbide or ceramic, while the second sealing ring 5 is made of resin-impregnated graphite or bronze. The roughness of the contact surfaces of the second sealing ring 5 and the first sealing ring 4 is ≤Ra0.8.

[0036] Considering that the end cap 2 is a rotating component in this embodiment, the first sealing ring 3 needs to move with it. Therefore, the structure of the first sealing ring 3 is as follows: Figure 3 As shown, an L-shaped structure is adopted, connecting the outer peripheral surface of the first sealing ring 4 and the corner of the end face away from the second sealing ring 5, and located at the corresponding corner of the end cap 2, achieving simultaneous sealing on both surfaces, increasing the sealing area, improving sealing reliability, and increasing the friction between the end cap 2, the first sealing ring 3, and the first sealing ring 4. In this embodiment, the structure of the second sealing ring 6 is as follows: Figure 4 As shown, the shape of its inner wall forms an interference fit with the outer wall of the motor shaft 1 and the second sealing ring 5.

[0037] In this embodiment, the elastic support assembly includes a second sealing ring support 7, a spring 8, and a spring base 9, all sleeved on the motor shaft 1. The second sealing ring support 7 is connected to the outer periphery of the second sealing ring 6, and one end of the spring 8 is connected to the second sealing ring support 7, while the other end is connected to the spring base 9. Figure 5 As shown, in this embodiment, one end of the spring 8 (upper part in the figure) is inserted into the spring base 9 and connected as a whole, with no relative movement between the two. The spring 8 is made of spring steel with high elasticity and corrosion resistance.

[0038] In order to provide support for the spring base 9, in this embodiment, the spring base 9 and the end cover 2 are interference-fitted, screwed or glued together. At the same time, a bearing 10 is connected between the motor shaft 1 and the end cover 2, and the spring base 9 abuts against one side of the bearing 10.

[0039] The mechanical seal device provided in the above embodiments can be applied to external rotor brushless DC motors, which can be used in hub motors. In addition, the mechanical seal device can also be applied to internal rotor motors.

[0040] In the description of this application, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They 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. Therefore, they should not be construed as limitations on this application.

[0041] The specific embodiments of this utility model have been described above. It should be understood that this utility model is not limited to the specific embodiments described above, and those skilled in the art can make various changes or modifications within the scope of the claims, which do not affect the substantive content of this utility model. Unless otherwise specified, the embodiments and features described in this application can be arbitrarily combined with each other.

Claims

1. A mechanical seal device, characterized in that, Used to seal the gap between the motor shaft (1) and the motor end cover (2); The mechanical seal device includes a first sealing ring (4), a second sealing ring (5), and an elastic support assembly sleeved on the motor shaft (1); The outer periphery of the first sealing ring (4) is fitted with a first sealing ring (3), the outer ring of the first sealing ring (3) is press-fitted with the inner wall of the end cap (2), and the inner ring of the first sealing ring (3) is press-fitted with the outer side of the first sealing ring (4), so that the first sealing ring (4) and the end cap (2) are sealed. The outer circumference of the second sealing ring (5) is fitted with a second sealing ring (6), and the second sealing ring (6) is also fitted on the motor shaft (1). The inner ring of the second sealing ring (6) is press-fitted with the second sealing ring (5) and the motor shaft (1) respectively, so that the second sealing ring (5) and the motor shaft (1) are sealed. The elastic support component is in a compressed state, with one end connected to the second sealing ring (6). The elastic force pushes the second sealing ring (5) against the first sealing ring (4), so that the contact surfaces of the second sealing ring (5) and the first sealing ring (4) are sealed.

2. The mechanical seal device according to claim 1, characterized in that, The elastic support assembly includes: a second sealing ring support seat (7), a spring (8), and a spring base (9) sleeved on the motor shaft (1); The second sealing ring support (7) is connected to the outer periphery of the second sealing ring (6), and one end of the spring (8) is connected to the second sealing ring support (7), and the other end is connected to the spring base (9).

3. The mechanical seal device according to claim 2, characterized in that, A bearing (10) is connected between the motor shaft (1) and the end cover (2), and the spring base (9) abuts against one side of the bearing (10).

4. The mechanical seal device according to claim 2, characterized in that, The spring base (9) and the end cap (2) are interference-fitted, screwed, or glued together.

5. The mechanical seal device according to claim 2, characterized in that, The spring (8) is made of spring steel.

6. The mechanical seal device according to claim 2, characterized in that, The spring (8) is fixedly connected to the spring base (9).

7. The mechanical seal device according to claim 1, characterized in that, The first sealing ring (3) and the second sealing ring (6) are made of elastic materials; The first sealing ring (4) is made of silicon carbide or ceramic; The second sealing ring (5) is made of resin-impregnated graphite or bronze.

8. The mechanical seal device according to claim 1, characterized in that, The roughness of the contact surfaces of the second sealing ring (5) and the first sealing ring (4) is ≤ Ra0.

8.

9. An external rotor brushless DC motor, characterized in that, Includes the mechanical seal device as described in any one of claims 1-8.

10. A hub motor, characterized in that, Including the external rotor brushless DC motor as described in claim 9.

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