Electric brush and electric motor

Abstract

The present invention relates to an electric brush and an electric motor. The electric brush comprises a contact surface used for providing a conductive connection by means of coming into sliding contact with a slip ring of an electric rotor, wherein the electric brush is made of a material having a porous structure, such that a self-lubricating effect can be provided by means of a capillary effect. The electric brush and electric motor of the present invention can improve the performance of electric brushes.

Description

Brushes and motors Technical Field

[0001] The present invention relates to the technical field of motors, and in particular to a brush and a motor comprising the brush. Background Art

[0002] Both generator and electric motors may require brushes. Brushes are components that provide sliding electrical contact in motors. They are fixed to the motor and make sliding contact with slip rings attached to the rotor shaft, providing a stable conductive connection between the rotating rotor and the stationary component.

[0003] In the prior art, brushes are typically made of graphite, while slip rings are typically made of copper alloys. Graphite brushes are also called carbon brushes. Graphite has good electrical conductivity, but is relatively low in hardness, making it susceptible to wear and debris during use. Splashing graphite debris can create unwanted electrical connections in the motor, posing a risk of short circuits. To reduce wear on the carbon brushes, lubricant is required on the contact surfaces, increasing maintenance costs. Furthermore, because the slip rings that mate with the carbon brushes are made of copper alloy, while the rotor shaft is typically made of steel, the slip rings need to be separately machined and then mounted on the rotor shaft, resulting in high manufacturing costs.

[0004] Summary of the Invention

[0005] Therefore, the technical problem to be solved by the present invention is to provide a brush and a motor that can improve the performance of the brush.

[0006] The above technical problems are solved by a brush according to the present invention. The brush includes a contact surface for sliding contact with the slip ring of a motor rotor to provide an electrically conductive connection. The brush is made of a material with a porous structure, which enables self-lubrication through the capillary effect. The porous structure absorbs and stores a certain amount of lubricating fluid through the capillary effect. When the brush and the slip ring slide in contact, the lubricating fluid stored in the porous structure seeps out to the contact surface through the capillary effect, thereby lubricating the contact surface and reducing wear.

[0007] According to a preferred embodiment of the present invention, the brush can be immersed in lubricating liquid, thereby storing lubricating liquid in the porous structure. During the brush manufacturing process, the lubricating liquid is stored in the capillary structure of the brush through the immersion process, particularly the vacuum suction process. Therefore, during the use of the brush, no additional lubricating liquid is required to be supplied to the contact surface.

[0008] According to another preferred embodiment of the present invention, the material forming the porous structure can be a copper-based alloy or a copper-graphite alloy. Copper-based alloys or copper-graphite alloys have high structural strength and are less likely to generate debris during use, thereby reducing debris contamination. In this case, the brushes can preferably be manufactured using a powder metallurgy process to form the porous structure.

[0009] According to another preferred embodiment of the present invention, the brush may be coated with graphite on at least the contact surface. Graphite has a low hardness and readily conforms to the slip ring surface during the initial contact phase, thereby providing stable contact. Graphite also reduces friction on the contact surface. Preferably, the entire surface of the brush may be coated with graphite.

[0010] According to another preferred embodiment of the present invention, the material of the brush may be doped with tungsten or tungsten carbide. Tungsten or tungsten carbide can increase the hardness of the brush, thereby improving the wear resistance of the brush.

[0011] According to another preferred embodiment of the present invention, the brush may include one or more grooves formed on the contact surface. The grooves can provide a certain gap between the contact surface of the brush and the slip ring, allowing the lubricating fluid stored in the porous structure of the brush to easily seep onto the contact surface through the capillary effect, thereby further improving the lubrication effect.

[0012] The above technical problem is also solved by an electric motor according to the present invention. The motor comprises a rotor, a slip ring, and the aforementioned brushes. The rotor includes a rotor shaft. The slip ring is mounted on the rotor shaft and in sliding contact with the brushes. The slip ring is made of steel. Since the matching brush does not require a graphite base material, the slip ring can be made of steel, thus saving costs. In this case, the slip ring can preferably be integrally formed with the rotor shaft, thereby reducing processing costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] The present invention is further described below with reference to the accompanying drawings. Elements with the same function are represented by the same reference numerals in the drawings.

[0014] FIG1 shows a perspective view of a brush according to an exemplary embodiment of the present invention; and

[0015] FIG2 is a schematic diagram showing an assembled state of a brush according to an exemplary embodiment of the present invention. DETAILED DESCRIPTION

[0016] The following detailed description and accompanying drawings are used to illustrate the principles of the present invention. The present invention is not limited to the preferred embodiments described. The scope of protection of the present invention is defined by the claims.

[0017] According to an embodiment of the present invention, a brush for a motor is provided. The motor may be an electric motor for generating kinetic energy or a generator motor for generating electrical energy. Figures 1 and 2 show exemplary embodiments of the brush according to the present invention.

[0018] FIG1 shows a perspective view of a brush 10 according to an exemplary embodiment of the present invention. As shown in FIG1 , the brush 10 can be formed as a substantially rectangular block, but this shape is merely schematic, and the brush 10 can have various different shapes as long as it is convenient for sliding contact with the slip ring. The brush 10 is formed with a contact surface 11. When the brush 10 is installed in a motor, the brush 10 is fixedly mounted relative to a stationary component in the motor and is electrically connected to a stationary component in the motor (such as an output line of a generator motor or a power supply line of an electric motor). The motor includes a rotor (not shown) that can rotate relative to the brush 10 and a slip ring (not shown) fixedly mounted on the rotor. The contact surface 11 of the brush 10 contacts the slip ring, and in particular, slides in contact with the slip ring when the rotor rotates, thereby providing a conductive connection between the brush 10 and the slip ring.

[0019] FIG2 shows a schematic diagram of the assembly state of a brush 10 according to an exemplary embodiment of the present invention. As shown in FIG2 , the brush 10 can be fixed to a bracket 20, which can be fixed to a component such as a stator or a housing of a motor (not shown). The contact surface 11 of the brush 10 faces a slip ring (not shown) on the rotor, in particular, on the rotor shaft of the rotor, and is in stable contact with the slip ring. Since the slip ring is generally an annular structure formed around the rotor shaft, in order to adapt to the shape of the radial outer side of the slip ring, the contact surface 11 of the brush 10 can also preferably form an arcuate surface adapted to the slip ring. One or more brushes 10 can be provided in the motor. When there are multiple brushes 10, these brushes 10 can preferably be fixed to the same bracket 20, or they can also be fixed to different brackets 20. The multiple brushes 10 fixed to the same bracket 20 can preferably be spaced circumferentially around the rotor shaft, in particular evenly spaced.

[0020] The brush 10 is made of a material with a porous structure. This means that a large number of, in particular, microscopic pores are distributed throughout the brush 10. The brush 10 with this porous structure is able to draw in lubricating fluid through the capillary effect, and this lubricating fluid is stored in the pore structure. When the contact surface 11 of the brush 10 contacts the slip ring and slides relative to it, the friction of the contact surface 11 generates heat, causing the lubricating fluid stored in the pore structure to seep out onto the contact surface 11 through the capillary effect, thereby lubricating and cooling the contact surface 11 and the slip ring. In this case, since the lubricating fluid comes from the pore structure inside the brush 10, no external lubricant is required, thus providing a self-lubricating effect.

[0021] Preferably, before the brush 10 is installed in the motor, especially during the manufacturing process of the brush 10, the brush 10 can be immersed in the lubricating liquid so that the brush 10 stores the lubricating liquid in its porous structure. The lubricating liquid stored in the porous structure thus becomes part of the product of the brush 10. During the use of the brush 10 in the motor, the lubricating liquid stored in the porous structure can gradually seep out through the capillary effect, thereby providing a long-term lubrication effect, especially during the entire service life of the brush 10, no additional lubricating liquid needs to be provided or replenished. Thereby, the maintenance cost of the brush 10 can be saved. Preferably, the immersion treatment of the brush 10 can especially be a vacuum suction treatment, that is, the brush 10 is immersed in a vacuum environment, so that the lubricating liquid can enter the pore structure of the entire brush 10 faster and more fully.

[0022] In a preferred embodiment, the brush 10 can be made of a copper-based alloy or a copper-graphite alloy, and the porous structure of the brush 10 is formed by the copper-based alloy or the copper-graphite alloy. In other words, the material forming the porous structure of the brush 10 is a copper-based alloy or a copper-graphite alloy. The copper-based alloy or the copper-graphite alloy here is the base material that constitutes the entire brush 10. The brush 10 made of the copper-based alloy or the copper-graphite alloy has a high structural strength and is less likely to generate debris during use, thereby reducing debris contamination. This brush 10 can be manufactured using a powder metallurgy process to form a porous structure within the copper-based alloy or copper-graphite alloy matrix.

[0023] Brushes 10 made of a copper-based alloy or copper-graphite alloy are preferably coated with graphite on at least the contact surface 11, and particularly on the entire surface. The graphite, as a coating on the copper-based alloy or copper-graphite alloy substrate, comes into direct contact with the slip ring. Because graphite has a low hardness and is easily deformed, the graphite coating on the substrate allows it to adapt more quickly to the slip ring during initial operation, thereby providing stable contact between the contact surface 11 and the slip ring.

[0024] In a further preferred embodiment, the material of brush 10, i.e., the copper-based alloy or copper-graphite alloy, may be doped with tungsten or tungsten carbide. Tungsten or tungsten carbide doped in the copper-based alloy or copper-graphite alloy can increase the overall hardness of brush 10, thereby making brush 10 more wear-resistant.

[0025] In a preferred embodiment, the brush 10 may include one or more grooves 12 formed on the contact surface 11. The shape and size of the grooves 12 can be specifically designed based on requirements (e.g., parameters such as pressure), and the grooves 12 can be distributed in various patterns on the contact surface 11 as needed. The grooves 12 provide a certain gap between the contact surface 11 of the brush 10 and the slip ring, allowing the lubricating fluid stored in the porous structure of the brush 10 to easily seep onto the contact surface 11 via the capillary effect, thereby further improving the lubrication effect.

[0026] According to another embodiment of the present invention, a motor is also provided. This motor includes a stator, a rotor, a slip ring, and a brush 10 according to any of the above embodiments. The rotor is capable of rotating relative to the stator. The rotor of the motor includes a rotor shaft, and the slip ring is fixedly mounted on the rotor shaft so that it can rotate with the rotor relative to the stator. The brush 10 is fixedly mounted relative to the stator and is electrically connected to a stationary component in the motor (such as the output line of the generator motor or the power supply line of the electric motor). When the motor is installed in place, the slip ring contacts the brush 10, and in particular, slides in contact with the slip ring when the rotor rotates, thereby providing an electrically conductive connection between the brush 10 and the slip ring. Preferably, the slip ring can be made of steel. Typically, the rotor shaft is also made of steel. In this case, the slip ring can preferably be formed integrally with the rotor shaft. That is, the slip ring can be served by a portion of the surface area of ​​the rotor shaft. This significantly reduces manufacturing costs.

[0027] The brushes according to the present invention have a porous structure, allowing lubricant to be stored within the porous structure through a capillary effect and automatically supplied to the contact surfaces. This makes the brushes self-lubricating, effectively reducing wear. Furthermore, such brushes can reduce or even eliminate the need to supply lubricant to the brushes during use, thereby reducing maintenance costs. Furthermore, such brushes can be manufactured from higher-strength alloys, thereby reducing debris generation and extending service life. In motors using such brushes, matching slip rings can be manufactured from steel, allowing them to be integrally formed with the rotor shaft, thereby reducing manufacturing costs.

[0028] While the foregoing descriptions illustrate possible embodiments, it should be understood that numerous variations exist through combinations of all known and other technical features and implementations readily conceivable to a skilled artisan. Furthermore, it should be understood that the exemplary embodiments serve merely as examples and in no way limit the scope, application, or configuration of the present invention. The foregoing descriptions are intended primarily to provide a skilled artisan with technical guidance for implementing at least one exemplary embodiment. Various modifications, particularly regarding the functionality and structure of the components described, may be made without departing from the scope of the claims.

[0029] Reference Signs

[0030] 10 brushes

[0031] 11 Contact surface

[0032] 12 grooves

[0033] 20 brackets

Claims

1. A brush (10) comprising a contact surface (11) for providing an electrically conductive connection in sliding contact with a slip ring of a rotor of an electric machine, It is characterized in that The brush (10) is made of a material with a porous structure, so that it can provide a self-lubricating effect through the capillary effect.

2. The brush (10) according to claim 1, characterized in that The brush (10) is immersed in lubricating liquid, so that the lubricating liquid is stored in the porous structure.

3. The brush (10) according to claim 1, characterized in that: The material forming the porous structure is a copper-based alloy or a copper-graphite alloy.

4. The brush (10) according to claim 3, characterized in that The brush (10) is manufactured by a powder metallurgy process to form the porous structure.

5. The brush (10) according to claim 3, characterized in that: The brush (10) is coated with graphite at least on the contact surface (11).

6. The brush (10) according to claim 5, characterized in that The brush (10) is coated with graphite on the entire surface.

7. The brush (10) according to claim 3, characterized in that The material of the brush (10) is doped with tungsten or tungsten carbide.

8. The brush (10) according to any one of claims 1 to 7, characterized in that: The brush (10) includes one or more grooves (12) formed on the contact surface (11).

9. An electric motor comprising a rotor, a slip ring and a brush (10) according to any one of claims 1 to 8, wherein the rotor comprises a rotor shaft, the slip ring is mounted on the rotor shaft and is in sliding contact with the brush (10), It is characterized in that The slip ring is made of steel.

10. The motor according to claim 9, characterized in that The slip ring is formed integrally with the rotor shaft.

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