A motor grounding carbon brush device
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-08-22
- Publication Date
- 2026-08-14
AI Technical Summary
[0004]目前，针对风力发电机轴电流的主流抑制方法是采用在转轴传动端或非传动端设置接地碳刷，常见的接地碳刷主要有碳块和导电毛刷两种类型：第一种碳块刷头，存在磨损问题，在使用过程中需要定期查和更换，更换碳块后还需进行预磨以保证电刷与转轴之间有效接触，并且在使用过程中会因磨损产生导电的碳粉，需要设置收集盒对碳粉进行收集，并对剩余碳粉进行定期清理，以防止碳粉累计发生短路或爬电故障，因此不适用于高转速电机上；第二种碳纤维碳刷采用毛刷结构，毛刷与主轴点接触，接触面积小，导电接触面小，且刷头的结构导致恢复刚度差，悬臂式的毛刷结构，接触转轴受力后刷头结构刚度不够容易倒伏，不能及时反弹恢复接触力，受力后刷头容易分散，导致接触状态不稳定，导电性能差，毛刷刷头与转轴的接触力无法调节，不能确保良好的导电接触状态
[0020]在本申请实施例中，本申请提供的电机接地碳刷装置，采用由若干碳纤维丝整体折弯形成周向分布于转子主轴外圈的碳纤维束环状刷头，代替传统碳块，碳纤维束环，实现碳纤维与转子主轴周向相切接触，实现转子主轴外周局部或者全部区域范围内主轴电流的导通，可以保证与接地装置的稳定接触，呈整体环状的碳纤维束刷头与旋转件接触阻力小，接触受力时反弹能力强，接触状态稳定可靠。另外，本申请不会产生碳粉，无需设置收集装置或定期清理碳粉。此外，该电机接地碳刷装置，结构更加简单，零部件少，工艺简单，安装方便，维护便捷，可以适用于各类型风电发电机，应用范围广泛。
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Figure CN224637909U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of wind power technology, and more specifically, to a motor grounding carbon brush device. Background Technology
[0002] The development and utilization of green, environmentally friendly, and clean energy has become an inevitable trend for future development. As a clean and renewable energy source, wind power has been vigorously developed in recent years.
[0003] As a core component of generator sets, wind turbines inevitably generate shaft currents during operation. The presence of shaft currents can damage the generator, such as causing bearing erosion, leading to premature bearing failure. Therefore, measures need to be taken to suppress shaft currents during the generator design phase.
[0004] Currently, the mainstream method for suppressing shaft current in wind turbines is to install grounding carbon brushes at either the driven or non-driven end of the shaft. Common grounding carbon brushes mainly come in two types: carbon blocks and conductive brushes. The first type, carbon block brushes, suffers from wear and requires regular inspection and replacement. After replacing the carbon block, pre-grinding is necessary to ensure effective contact between the brush and the shaft. Furthermore, conductive carbon powder is generated during use due to wear, requiring a collection box to collect the powder and regular cleaning of any remaining powder to prevent short circuits or creepage faults. Therefore, it is not suitable for high-speed motors. The second type, carbon fiber brushes, uses a brush structure with point contact between the brush and the main shaft. This results in a small contact area and a small conductive contact surface. The brush head structure also leads to poor recovery stiffness. The cantilevered brush structure is prone to collapse under stress on the shaft, failing to rebound and recover the contact force in time. Under stress, the brush head tends to disperse, leading to unstable contact and poor conductivity. The contact force between the brush head and the shaft cannot be adjusted, failing to ensure a good conductive contact state. Utility Model Content
[0005] This application provides a motor grounding carbon brush device, which enables the conduction of main shaft current in a local or all area of the outer periphery of the rotor main shaft, can stably contact and conduct electricity with the rotor main shaft, and can reduce shaft voltage to achieve the function of preventing shaft electrolytic corrosion.
[0006] This application provides a motor grounding carbon brush device, comprising:
[0007] Rotor spindle;
[0008] A grounding ring is disposed on the outside of the rotor main shaft, and the grounding ring has multiple mounting holes at least along the circumferential direction of the rotor main shaft;
[0009] A carbon fiber bundle ring is circumferentially distributed around the outer ring of the rotor spindle. The carbon fiber bundle ring includes multiple carbon fiber bundle units and a carbon fiber bundle connector that connects two adjacent carbon fiber bundle units end to end. Each carbon fiber bundle unit includes two fixing parts and a bent part formed by bending the two fixing parts towards each other. The two fixing parts are fixed to the mounting hole. The bent part is disposed between the rotor spindle and the grounding ring. At least a portion of the bent part is used to make contact with the rotor spindle for conductive connection. The carbon fiber bundle connector is used to connect an external grounding terminal.
[0010] In some embodiments, the extension direction of the carbon fiber bundle monomer intersects the axial direction of the rotor spindle.
[0011] In some embodiments, the carbon fiber bundle monomers are in contact with and connected to the rotor main shaft along the radial direction of the rotor main shaft.
[0012] In some embodiments, the center angle of the grounding ring ranges from 30° to 360°.
[0013] In some embodiments, the plurality of mounting holes are distributed along the circumferential direction and the axial direction; there are multiple carbon fiber bundle rings, which are spaced apart from the grounding ring along the axial direction.
[0014] In some embodiments, the bending portion includes a bending sub-part and two connecting parts, the bending sub-part being used to elastically abut against the rotor main shaft, and the connecting parts connecting the bending sub-part and the fixing part.
[0015] In some embodiments, the bending portion is convex, and the bending portion bends and protrudes toward one side of the rotor spindle.
[0016] In some embodiments, the opening width of the bent portion is less than or equal to the opening width of the two connecting portions.
[0017] In some embodiments, the carbon fiber bundle rings surround the outer circumferential surface of the rotor main shaft at a 360° angle relative to the axis of the rotor main shaft;
[0018] The carbon fiber bundle ring includes multiple carbon fiber bundle units and multiple carbon fiber bundle connectors. The carbon fiber bundle units are disposed inside the grounding ring, and the carbon fiber bundle connectors are disposed outside the grounding ring. All the carbon fiber bundle connectors are sequentially connected to adjacent carbon fiber bundle units to form a circumferentially closed carbon fiber bundle ring.
[0019] In some embodiments, the mounting hole is provided with an internal thread; the motor grounding carbon brush device further includes a fixing member, the fixing member is provided with an inner hole and an external thread, the inner hole is sleeved on the fixing part, and the fixing member is connected to the internal thread through the external thread.
[0020] In this embodiment, the motor grounding carbon brush device provided uses a carbon fiber bundle annular brush head formed by bending several carbon fiber filaments as a whole and distributing them circumferentially around the outer ring of the rotor main shaft, replacing the traditional carbon block and carbon fiber bundle ring. This achieves tangential contact between the carbon fiber and the rotor main shaft circumferentially, enabling the conduction of main shaft current in a local or all area of the outer circumference of the rotor main shaft. This ensures stable contact with the grounding device. The integral annular carbon fiber bundle brush head has low contact resistance with rotating parts, strong rebound ability under contact force, and stable and reliable contact. In addition, this application does not generate carbon dust, eliminating the need for a collection device or regular cleaning of carbon dust. Furthermore, this motor grounding carbon brush device has a simpler structure, fewer parts, simpler manufacturing process, convenient installation, and convenient maintenance. It can be applied to various types of wind turbine generators and has a wide range of applications. Attached Figure Description
[0021] 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 embodiments of this application. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.
[0022] Figure 1 This is a schematic diagram of the structure of a motor grounding carbon brush device provided in some embodiments of this application;
[0023] Figure 2 A front view of a motor grounding carbon brush device provided in some embodiments of this application;
[0024] Figure 3 This is a schematic diagram of the structure of the motor grounding carbon brush device provided in some embodiments of this application, excluding the rotor spindle;
[0025] Figure 4 This is a schematic diagram of the structure of the carbon fiber bundle and fixing element in the motor grounding carbon brush device provided in some embodiments of this application.
[0026] The attached figures are labeled as follows:
[0027] 1-Rotor spindle; 2-Grounding ring; 3-Carbon fiber bundle ring; 4-Fixed component;
[0028] 31-Carbon fiber bundle monomer; 32-Carbon fiber bundle connector;
[0029] 311-Bending part; 312-Fixing part; 3111-Bending part; 3112-Connecting part. Detailed Implementation
[0030] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.
[0031] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used in the description of this application is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion. The terms "first," "second," etc., are used to distinguish different objects, not to describe a particular order or hierarchy.
[0032] In this application, the reference to "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment that is mutually exclusive with other embodiments.
[0033] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "attachment" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.
[0034] In this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, in this application, the character " / " generally indicates that the preceding and following related objects have an "or" relationship.
[0035] In the embodiments of this application, the same reference numerals denote the same components, and for the sake of brevity, detailed descriptions of the same components are omitted in different embodiments. It should be understood that the thickness, length, width, and other dimensions of various components in the embodiments of this application shown in the accompanying drawings, as well as the overall thickness, length, width, and other dimensions of the integrated device, are merely illustrative and should not constitute any limitation on this application.
[0036] In this application, "multiple" means two or more (including two).
[0037] Please refer to Figure 1 and Figure 2 , Figure 1 This is a schematic diagram of the structure of a motor grounding carbon brush device provided in some embodiments of this application; Figure 2 This is a front view of a motor grounding carbon brush device provided in some embodiments of this application.
[0038] This application provides a motor grounding carbon brush device, including a rotor main shaft 1, a grounding ring 2, and a carbon fiber bundle ring 3. The rotor main shaft 1 is disposed in the inner ring of the grounding ring 2. The grounding ring 2 has a ring-shaped structure and is disposed on the outer side of the rotor main shaft 1. The grounding ring 2 has a plurality of mounting holes, which are distributed at least along the circumferential direction of the rotor main shaft 1. The mounting holes can be through holes that penetrate along the wall thickness direction of the grounding ring 2 to facilitate the installation of the carbon fiber bundle ring 3.
[0039] refer to Figure 3 The carbon fiber bundle ring 3 is circumferentially distributed around the outer ring of the rotor main shaft 1. The carbon fiber bundle ring 3 includes multiple carbon fiber bundle units 31 and at least one carbon fiber bundle connector 32. Two adjacent carbon fiber bundle units 31 are connected end to end by the carbon fiber bundle connector 32 to form the carbon fiber bundle ring 3. The carbon fiber bundle unit 31 includes two fixing parts 312 and a bending part 311. The two fixing parts 312 are fixed to the mounting hole. The bending part 311 is formed by bending the two fixing parts 312 towards each other. The bending part 311 is disposed between the rotor main shaft 1 and the grounding ring 2 so that at least a part of the bending part 311 is in contact with the rotor main shaft 1 for conductive connection. The carbon fiber bundle connector 32 can connect adjacent carbon fiber bundle units 31 and is externally grounded, thereby avoiding damage to bearings and other components caused by the main shaft current.
[0040] The carbon fiber bundle ring 3 may include one or more carbon fiber bundle units 31. Each carbon fiber bundle unit 31 is composed of carbon fiber filaments. The two ends of each carbon fiber bundle unit 31 are separated from each other and form fixed ends, which are fixed in their respective mounting holes in the grounding ring 2. In this way, the carbon fiber bundle ring 3 can wrap around the outer wall of the rotor shaft 1 and form a stable contact with the rotor shaft 1 to achieve a conductive effect. The carbon fiber bundle brush head is grounded, eliminating the potential difference between the inner and outer rings of the bearing, preventing electro-corrosion damage to bearings and other components, reducing shaft voltage, and achieving the function of preventing shaft electro-corrosion.
[0041] Furthermore, the carbon fiber bundle monomer 31 and the carbon fiber bundle connector 32 in this application can be integrally formed by bending carbon fiber filaments to improve the connection strength.
[0042] The motor grounding carbon brush device provided in this application replaces the traditional carbon brush structure. Compared with the dispersed contact of the traditional carbon brush head and the point contact of the carbon fiber bundle individual 31, the continuous annular carbon fiber bundle ring 3 structure in this application forms a continuous annular contact conductivity with the rotor main shaft 1. The contact area is an arc-shaped area. Compared with the point contact conductivity structure of the traditional brush head, the contact of this application is smooth, with low friction and strong recovery stiffness. After the contact rotor shaft is subjected to force, the brush head is not easy to fall over and can rebound in time to restore the contact force. The contact state is stable and the conductivity is strong.
[0043] Continue to refer to Figure 3 In one specific embodiment, the extension direction of the carbon fiber bundle monomer 31 intersects the axial direction of the rotor main shaft 1. The grounding ring 2 can be a ring structure. The extension direction of the carbon fiber bundle monomer 31 can be along the radial direction of the rotor main shaft 1, or the extension direction of the carbon fiber bundle monomer 31 can be generally along the radial direction of the rotor main shaft 1. For example, the carbon fiber bundle monomer 31 and the axial direction of the rotor main shaft 1 are distributed at a certain angle. This application does not limit this, but it is necessary to ensure that the bent part 311 of the carbon fiber bundle monomer 31 is in contact with the rotor main shaft 1, and the fixing part 312 is fixedly connected to the grounding ring 2.
[0044] Optionally, the carbon fiber bundle monomers 31 are in contact with the rotor main shaft 1 in the radial direction, that is, the extension direction of the carbon fiber bundle monomers 31 is perpendicular to the axial direction of the rotor main shaft 1, and the carbon fiber bundle monomers 31 are in contact with the rotor main shaft 1 in the radial direction. In this way, each carbon fiber bundle monomer 31 is in elastic contact with the rotor main shaft 1 to form radial conduction, thereby enabling the carbon fiber bundle monomers 31 to have a large deformation capacity in both the axial and radial directions. During operation, the contact state can be automatically adjusted, and a stable contact conductivity effect can be easily obtained.
[0045] In one specific embodiment, the carbon fiber bundle ring 3 formed by connecting multiple carbon fiber bundle monomers 31 and multiple carbon fiber bundle connectors 32 can be distributed in the corresponding half, one-third, one-quarter, one-fifth, one-sixth, one-seventh, and one-eighth regions of the rotor main shaft 1. The grounding ring 2 has multiple mounting holes. The number of mounting holes for the carbon fiber brush assembly can be designed according to the magnitude of the motor shaft current. It should be ensured that each mounting hole on the grounding ring 2 is equipped with a corresponding carbon fiber bundle, and that the shaft current is quickly and timely discharged.
[0046] Correspondingly, the central angle of the grounding ring 2 ranges from 30° to 360°. The curvature and height of the grounding ring 2 can be designed according to the number and distribution area of the carbon fiber bundle rings 3. The grounding ring 2 can be a complete circular structure or a partial circular structure, such as a half-circle ring, a third-circle ring, a quarter-circle ring, a fifth-circle ring, a sixth-circle ring, a seventh-circle ring, an eighth-circle ring, etc. The size of the grounding ring 2 can be various, and this application does not limit it.
[0047] refer to Figure 4 and combined Figure 1 In one optional embodiment, the grounding ring 2 has a circular structure, and correspondingly, the carbon fiber bundle rings 3 are distributed in a circular shape, surrounding the outer circumferential surface of the rotor main shaft 1 at a 360° angle relative to the axis of the rotor main shaft 1. The carbon fiber bundle ring 3 includes multiple carbon fiber bundle units 31 and multiple carbon fiber bundle connectors 32. The carbon fiber bundle units 31 are disposed inside the grounding ring 2, and the carbon fiber bundle connectors 32 are disposed outside the grounding ring 2. All the carbon fiber bundle connectors 32 are sequentially connected end to end to adjacent carbon fiber bundle units 31, thereby forming a circumferentially closed carbon fiber bundle ring 3.
[0048] In this embodiment, one or more carbon fiber bundle rings 3 can be arranged circumferentially, and the carbon fiber bundle rings 3 can be continuously distributed or spaced apart. At least a portion of the bent portion 311 of the carbon fiber bundle unit 31 abuts against the rotor main shaft 1, and the fixing portion 312 of the carbon fiber bundle unit 31 is fixedly connected to the mounting hole.
[0049] In addition, multiple carbon fiber bundle rings 3 can be arranged along the axial direction of the rotor main shaft 1, and the multiple carbon fiber bundle rings 3 are spaced apart along the axial direction on the grounding ring 2. Correspondingly, multiple mounting holes are spaced apart along the circumferential direction and the axial direction, and the two fixed ends of the carbon fiber bundle individual 31 and the two connecting ends of the carbon fiber bundle connector 32 are respectively fixedly installed in two adjacent mounting holes.
[0050] The conductive structure, forming a circumferential and axial distribution around the outer ring of the rotor main shaft 1, allows current from various points on the rotor main shaft 1 to be introduced into and discharged from the carbon fiber bundle ring 3. This achieves circumferential tangential contact between the carbon fiber and the rotor main shaft 1, ensuring stable contact with the grounding device, improving the stability and reliability of conductivity, and facilitating maintenance. It should be noted that the arrangement of the carbon fiber bundles on the grounding ring 2 can be designed with different distribution numbers, spacings, and positions, etc., as required; this application does not impose any limitations on this.
[0051] Furthermore, each carbon fiber bundle ring 3 is distributed at equal intervals along the circumferential and axial directions. This arrangement makes the conductivity more uniform and the conductivity more stable and reliable.
[0052] Continue to refer to Figure 4 Regarding the structure of the bending portion 311, in one specific embodiment, it includes a bending sub-portion 3111 and two connecting portions 3112. The bending sub-portion 3111 is used to elastically abut against the rotor main shaft 1, and the connecting portions 3112 connect the bending sub-portion 3111 and the fixing portion 312. The bending portion 311 mainly conducts electricity through contact with the rotor main shaft 1, and the fixing portion 312, connecting portion 3112, bending portion 3111, another connecting portion 3112, and another fixing portion 312 are sequentially connected to form a continuous carbon fiber bundle monomer 31.
[0053] Optionally, the opening width of the bent portion 3111 is less than or equal to the opening width of the two connecting portions 3112. Thus, the bent portion 3111 forms a U-shaped or semi-circular structure, resulting in low contact resistance between the carbon fiber bundle brush head and the rotating component. The carbon fiber bundle brush head forms a brush head with good elasticity and stable contact force, unlike distributed independent brush heads. It has strong rebound ability when subjected to contact force, and the contact state is stable and reliable. Its manufacturing process is simple and installation is convenient.
[0054] Continue to refer to Figure 4 The bending portion 3111 is convex outward, and the bending portion 3111 bends and protrudes towards the side of the rotor main shaft 1, which can further improve the contact elasticity of the carbon fiber bundle monomer 31, increase the radial free deformation performance, reduce the contact area between the carbon fiber bundle monomer 31 and the rotor main shaft 1, and improve the conductivity.
[0055] The carbon fiber bundle monomer 31 and carbon fiber bundle connector 32 in this application can be directly fixed in the mounting hole, or they can be fixed in the mounting hole of the grounding ring 2 by means of the fastener 4. For example, the mounting hole is provided with an internal thread, and the motor grounding carbon brush device also includes a fastener 4. The fastener 4 is provided with an inner hole and an external thread. The inner hole is fitted onto the fixing part 312 and ensures that the two are tightly connected. The fastener 4 is connected to the internal thread of the grounding ring 2 by the external thread. In addition, the fastener 4 can be threadedly connected by locking parts (e.g., nuts, bolts) to fix the axial position of the fastener 4. By adjusting the distance between the nut and the threaded bolt and the length of the carbon fiber, carbon fiber brush heads with different contact densities can be formed, so as to realize the setting and adjustment of the initial contact stiffness.
[0056] It should be noted that the carbon fiber bundle unit in this application can be fixed integrally with the grounding ring or be fixed in a detachable manner. The installation method of the carbon fiber bundle ring can be adjusted according to the actual use situation, and this application embodiment does not limit this.
[0057] The above provides a detailed description of the motor grounding carbon brush device provided in this application. Specific examples have been used to illustrate the principles and implementation methods of this application. The descriptions of the embodiments above are merely for the purpose of helping to understand the method and core ideas of this application. It should be noted that those skilled in the art can make various improvements and modifications to this application without departing from its principles, and these improvements and modifications also fall within the protection scope of this application.
Claims
1. An electric machine ground carbon brush apparatus, characterized by, include: Rotor spindle (1); A grounding ring (2) is provided on the outside of the rotor main shaft (1), and the grounding ring (2) has a plurality of mounting holes at least along the circumferential direction of the rotor main shaft (1); A carbon fiber bundle ring (3) is circumferentially distributed on the outer ring of the rotor main shaft (1). The carbon fiber bundle ring (3) includes a plurality of carbon fiber bundle units (31) and a carbon fiber bundle connector (32) that connects two adjacent carbon fiber bundle units (31) in sequence. The carbon fiber bundle unit (31) includes two fixing parts (312) and a bent part (311) formed by bending the two fixing parts (312) towards each other. The two fixing parts (312) are fixed to the mounting hole. The bent part (311) is disposed between the rotor main shaft (1) and the grounding ring (2). At least a portion of the bent part (311) is used to make contact and conductive connection with the rotor main shaft (1). The carbon fiber bundle connector (32) is used to connect to an external grounding terminal.
2. The motor ground carbon brush apparatus of claim 1, wherein, The extension direction of the carbon fiber bundle (31) is intersected with the axial direction of the rotor main shaft (1).
3. The motor ground carbon brush apparatus of claim 2, wherein, The carbon fiber bundle monomer (31) is in contact with the rotor main shaft (1) in the radial direction of the rotor main shaft (1).
4. The motor ground carbon brush apparatus of claim 2, wherein, The center angle of the grounding ring (2) ranges from 30° to 360°.
5. The motor ground carbon brush apparatus of claim 4, wherein, The plurality of mounting holes are distributed along the circumferential direction and the axial direction; There are multiple carbon fiber bundle rings (3), and the multiple carbon fiber bundle rings (3) are distributed at intervals along the axial direction on the grounding ring (2).
6. The motor ground carbon brush apparatus of any one of claims 1 to 5, wherein, The bending part (311) includes a bending sub-part (3111) and two connecting parts (3112). The bending sub-part (3111) is used to elastically abut against the rotor main shaft (1), and the connecting parts (3112) connect the bending sub-part (3111) and the fixing part (312).
7. The motor ground carbon brush apparatus of claim 6, wherein, The bending section (3111) is convex and bends outward toward the rotor main shaft (1).
8. The motor ground carbon brush apparatus of claim 7, wherein, The opening width of the bent portion (3111) is less than or equal to the opening width of the two connecting portions (3112).
9. The motor ground carbon brush apparatus of claim 1, wherein, The carbon fiber bundle ring (3) surrounds the outer circumferential surface of the rotor main shaft (1) at 360° relative to the axis of the rotor main shaft (1); The carbon fiber bundle ring (3) includes multiple carbon fiber bundle units (31) and multiple carbon fiber bundle connectors (32). The carbon fiber bundle units (31) are disposed on the inner side of the grounding ring (2), and the carbon fiber bundle connectors (32) are disposed on the outer side of the grounding ring (2). All the carbon fiber bundle connectors (32) are connected end to end to adjacent carbon fiber bundle units (31) to form a circumferentially closed carbon fiber bundle ring (3).
10. The motor ground carbon brush apparatus of claim 1, wherein, The mounting hole is provided with an internal thread; the motor grounding carbon brush device also includes a fixing member (4), the fixing member (4) is provided with an inner hole and an external thread, the inner hole is sleeved on the fixing part (312), and the fixing member (4) is connected to the internal thread through the external thread.