Ground brush, ground brush unit and device
By using a combination of conductive carbon fiber, graphene, and pitch-based carbon fiber in the grounding brush, the problems of high friction and wear between the shaft and bearing in the grounding brush are solved, achieving low noise, low wear, and efficient cooling, while reducing costs.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-09-18
- Publication Date
- 2026-03-27
AI Technical Summary
Existing grounding brushes have high friction between the shaft and bearing, leading to shaft wear and reduced conductivity, and lack effective lubrication and cooling methods.
Different types of filaments, including conductive carbon fiber, graphene, and pitch-based carbon fiber, are combined with polytetrafluoroethylene (PTFE) to form a grounding brush with low friction, low noise, good lubrication, and efficient cooling. The brush is then fixed to the device housing by press fitting.
It achieves low friction, low noise, and low wear, improves shaft life and electrical conductivity, and eliminates the need for liquid lubricant, thus reducing costs.
Smart Images
Figure CN121748897A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to a grounding brush, a grounding brush unit, and an apparatus having a grounding brush unit. Background Technology
[0002] Grounding brushes with graphite filaments are known. Furthermore, grounding brushes are known to be used on coated areas of the shaft and on coated bushes located on the shaft. Summary of the Invention
[0003] The problem of this invention is particularly how to achieve high efficiency. According to the invention, this problem is solved by the features of technical solution 1, while advantageous embodiments of the invention are the subject of the dependent claims.
[0004] The present invention starts with a grounding brush having a first set of filaments of a first type and at least a second set of filaments.
[0005] The second group of filaments is proposed to belong to a second type, different from the first type. Under the phrase "belongs to a type," it should be specifically understood that: the filament is composed of a material specific to (or dedicated to) that type, and / or has a mass that deviates less than 20% (by weight) from that specific type, and / or has a conductivity that deviates less than 20% from that specific type. Under the phrase "different from the first type," it should be specifically understood that: the material specific to the first type is different from the material specific to the second type, and / or the mass specific to the first type deviates more than 5% from that specific type, and / or the conductivity specific to the first type deviates more than 5% from that specific type. Under "set," it should be specifically understood as a mathematical group. Thus, high efficiency can be achieved. In particular, a good formation of characteristics in the grounding brush that differ from the conductivity can be achieved.
[0006] Specifically, the filament can be a fiber and / or bristle and / or a piece of wire. In particular, the filaments in the first group can be conductive. For example, the filaments in the first group can be carbon fiber.
[0007] Advantageously, at least a majority of the filaments in the second group are composed of one or more solid lubricants. Under the phrase "a majority" of the filaments are composed of a certain material, it should be specifically understood that the portion of the filaments comprising more than fifty percent of their weight is composed of that material. This allows for good lubrication of the relative motion between the filaments in the first group and the shaft during operation, especially when the area around the filaments in the first group is dry and therefore without liquid lubricant. In particular, the friction between the filaments in the first group and the shaft can be very low, and wear and oxidation of the shaft, as well as a reduction in the electrical conductivity between the filaments in the first group and the shaft, can be largely avoided.
[0008] Furthermore, it is proposed that the filaments of the second group are at least partially composed of polytetrafluoroethylene and / or graphene. This enables low noise during operation, low wear on the shaft in contact with the filaments of the second group during operation, and good ability to maintain contact with the shaft during operation.
[0009] Advantageously, the grounding brush includes a third group of filaments belonging to the third type, and this third type differs from the first and second types. This allows for high efficiency. In particular, it enables the formation of several properties of the grounding brush that differ from its electrical conductivity. Specifically, the filaments of the third group can have better thermal conductivity than those of the filaments of the first and second groups.
[0010] Furthermore, a second group of filaments was proposed to have a higher thermal conductivity than the first group of filaments. This allows for better cooling and lower wear of the material in contact with the grounding brush during operation.
[0011] In particular, the thermal conductivity of filaments specific to the second type can be at least 15% higher than that of filaments specific to the first type.
[0012] Advantageously, the filaments in the second group are pitch-based carbon fibers. This allows for the achievement of particularly high thermal conductivity in the second group of filaments.
[0013] Advantageously, the total number of filaments in the first group is between 40% and 75% of the total number of filaments in the grounding brush, and / or the total number of filaments in the second group is between 25% and 60% of the total number of filaments in the grounding brush. Thus, a good balance is achieved between the effectiveness of the first group of filaments and the effectiveness of the second group of filaments.
[0014] Furthermore, a grounding brush unit with the grounding brush described above is proposed, wherein a carrier unit is fixed to the grounding brush. This allows for efficient installation of the grounding brush onto the housing.
[0015] In addition, a device with a grounding brush unit is proposed.
[0016] Advantageously, the device includes a shaft with a contact ground brush and an uncoated surface area. This allows for a cost-effective construction.
[0017] Further advantages will become apparent in the following description of the accompanying drawings. Examples of embodiments of the invention are illustrated in the drawings. The drawings, description, and claims contain numerous combinations of features. Those skilled in the art will also readily consider these features individually and combine them to form other useful combinations. Attached Figure Description
[0018] Figure 1 A front view of a grounding brush unit with a grounding brush according to the present invention is shown.
[0019] Figure 2 It shows crossing according to Figure 1 The II-II section of the grounding brush unit,
[0020] Figure 3 It shows passing through with according to Figure 1 Section III-III of the grounding brush unit device, and
[0021] Figure 4 A perspective view of the grounding brush unit is shown.
[0022] Figure label:
[0023] Detailed Implementation
[0024] Figure 1 A front view of a grounding brush unit 20 having a grounding brush 10 according to the present invention is shown. The grounding brush unit 20 includes a one-piece metal carrier unit 18, which is fixed to the grounding brush in a form-fit manner. Figures 1 to 4 The grounding brush includes the first group of filaments belonging to the first type 12. Figure 3Furthermore, the grounding brush includes a second set of filaments 14 belonging to the second type. The first and second types differ. The filaments 12 of the first set are conductive carbon fibers. The filaments 14 of the second set are entirely composed of graphene. Alternatively, the filaments 14 of the second set are partially or entirely composed of polytetrafluoroethylene (PTFE). Alternatively, the second set may also include filaments wholly or partially composed of PTFE and filaments composed of graphene. Therefore, the filaments 14 are at least partially composed of a solid lubricant. During operation, the filaments 14 also have a cleaning effect.
[0025] Furthermore, the grounding brush includes a third group of filaments 16 belonging to the third type. The third type of filaments 16 are pitch-based carbon fibers. The third group of filaments 16 has a higher thermal conductivity than the first group of filaments. Therefore, they help cool the shaft 24 in the fully assembled state. In the fully assembled state, the grounding brush unit is device 22 ( Figure 3 Part of the device housing 28. In this state, the carrier unit 18 is fixed to the housing 28 of the device by means of a portion 30 of the ring segment shaped pieces 32 of the carrier unit 18, the portion 30 of the ring segment shaped pieces 32 extending in the axial direction of the grounding brush.
[0026] The grounding brush 10 has a ring segment shape. This ring segment is almost a ring. All the filaments of the grounding brush are secured to the bearing element 36 of the grounding brush by wire 34 (with the help of wire 34). The bearing element 36 also has a ring segment shape. Furthermore, the last mentioned ring segment is also almost a ring. In the axial section ( Figure 2 and Figure 3 In this structure, the carrier element is U-shaped, with its two ends bent toward each other, pressing the filaments of the grounding brush together, thus securing the filaments to the carrier element 36. Lugs 38 of the carrier unit are bent around the carrier element 36, securing the carrier element 36 to the carrier unit 18. Figure 2 In summary, the filaments of the grounding brush are electrically connected to the housing 28 via the carrier element and carrier unit. The housing 28 is also conductive.
[0027] The device 22 includes a shaft 24 that rotates relative to the housing 28 and relative to the grounding brush unit during operation. The shaft includes a surface area 26 that contacts the grounding brush 10 and is uncoated.
[0028] Shaft 24 is rotatably supported relative to housing 28 by bearings (not shown). Especially during operation, current can flow from shaft 24 through, in particular, the filaments 12 of the first set and through the bearing elements and support units to housing 28. This prevents current from flowing through the bearings to housing 28, thus protecting the bearings from damage.
[0029] This device can operate without liquid lubricant in areas containing grounding brushes.
[0030] The device could be, for example, part of an electric motor that supplies driving force to a vehicle, or part of an industrial application.
[0031] All the filaments of the grounding brush can be fibers.
[0032] Figure 4 A perspective view of the grounding brush unit is shown.
[0033] Compared to grounding brushes with graphite fibers, the grounding brush of the present invention has the following advantages: lower noise, lower wear (which increases the life of the components, especially the shaft), and better ability to maintain contact with the shaft due to the flexibility of the filaments.
[0034] Alternatively, the grounding brush does not have a third group of filaments 16. In this case, the total number of filaments 12 in the first group is between 40% and 75% of the total number of filaments in the grounding brush, particularly between 50% and 66%. Furthermore, in this case, the total number of filaments 14 in the second group is between 25% and 60% of the total number of filaments in the grounding brush, particularly between 33% and 50%.
[0035] As an alternative, the grounding brush does not have the second set of filaments 14.
Claims
1. A grounding brush (10) comprising: a first set of filaments (12) of a first type, and at least a second set of filaments (14), Its features are, The filaments (14) of the second group belong to a second type that is different from the first type.
2. The grounding brush (10) according to claim 1, Its features are, Each of the filaments (14) in the second group is composed of at least a majority of one or more solid lubricants.
3. The grounding brush (10) according to claim 2, Its features are, The filaments (14) of the second group are at least partially composed of polytetrafluoroethylene and / or graphene.
4. The grounding brush (10) according to at least one of the preceding claims, Its features are, The grounding brush includes a third group of filaments (16) belonging to a third type, and the third type is different from the first type and the second type.
5. The grounding brush (10) according to at least one of the preceding claims, Its features are, The filaments (14) of the second group have a higher thermal conductivity than the filaments (12) of the first group.
6. The grounding brush (10) according to claim 5, Its features are, The filaments (14) in the second group are pitch-based carbon fibers.
7. The grounding brush (10) according to at least one of the preceding claims, Its features are, The total number of filaments (12) in the first group is between 40% and 75% of the total number of filaments (12, 14, 16) in the grounding brush, and / or the total number of filaments (14) in the second group is between 25% and 60% of the total number of filaments (12, 14, 16) in the grounding brush.
8. A grounding brush unit (20) having a grounding brush (10) according to at least one of the preceding claims, characterized in that, The grounding brush unit (20) has a carrier unit (18) which is fixed to the grounding brush.
9. An apparatus (22) having a grounding brush unit (20) according to claim 8.
10. The apparatus (22) according to claim 9, characterized in that, The device (22) has a shaft (24) having a surface area (26) that contacts the grounding brush (10) and is uncoated.