Electric brush assembly, motor and electric tool

Abstract

The utility model discloses an electric brush assembly, a motor and an electric tool. The electric brush assembly comprises a brush carrier; the brush body is arranged on the brush frame, and a stop groove is formed in the surface of the brush body; the scroll coil spring is arranged on the brush frame, the scroll coil spring comprises a tension part and a compression part, the tension part abuts against the brush body, the compression part is wound around the brush frame, the tension part comprises a working position and a disassembly and assembly position separated from the working position, and at least part of the tension part in the disassembly and assembly position state is located in the stop groove. According to the design, modular assembly of the brush assembly can be realized, the rotor maintenance difficulty is reduced, and the service life of the brush is prolonged.

Description

Technical Field

[0001] This application relates to the field of tool technology, and in particular to a brush assembly, a motor, and a power tool. Background Technology

[0002] Conventional brushes are typically only designed to work with the commutator of a motor to transmit energy through wear, lacking other auxiliary functions.

[0003] When the rotor of a motor encounters problems during use and requires repair or replacement, the scroll spring needs to be moved away from the brush position. Then, the brushes need to be peeled off from the commutator contact surface of the rotating motor before the rotor can be removed from the machine. However, this operation is cumbersome, and there is no stopping structure after the brushes are peeled off the commutator surface. This means that during rotor disassembly, the brushes may slide along the guide grooves of the metal brush holder and come into contact with the commutator surface, affecting rotor replacement and repair.

[0004] After the brush is removed, the spiral spring usually rests against the nearby metal brush holder. However, due to the structural shape of the brush holder, some spiral springs do not have a stable resting position on the brush holder after removal. In this case, the spiral spring can only return to its initial relaxed state. After replacing or repairing the rotor, the spiral spring can be adjusted to a tensioned state using auxiliary tools. This operation not only increases the difficulty of replacing or repairing the rotor, but also, due to improper operation when readjusting the spiral spring to a tensioned state, can result in a different spring force value than the initial value, affecting the service life of the brush.

[0005] Because the existing structure lacks an effective stopping mechanism and the brushes are subjected to spring force compression from the scroll spring under tension during assembly, only the metal brush holder and scroll spring can be assembled as a single unit. The brushes themselves need to be installed separately during the final assembly, making it impossible to achieve a modular assembly of the metal brush holder, scroll spring, and brushes as a single unit. This significantly impacts the efficiency of the final assembly process and presents a disadvantage for modular and component-based production. Utility Model Content

[0006] To address the shortcomings of existing technologies, this application provides a brush assembly, a motor, and a power tool, which facilitates modular assembly of the brush assembly, reduces the difficulty of rotor maintenance, and improves brush life.

[0007] This application provides a brush assembly, including:

[0008] Brush holder;

[0009] A brush body is disposed on the brush holder, and a stop groove is provided on the surface of the brush body;

[0010] A spiral spring is disposed on the brush holder. The spiral spring includes a tension portion that abuts against the brush body and a compression portion that is coiled around the brush holder. The tension portion includes a working position and a disassembled position that is out of the working position. When the tension portion is in the disassembled position, it is at least partially located in the stop groove.

[0011] A further improvement is as follows: the brush body includes a first surface and a second surface that are adjacent to each other, the stop groove is provided on the first surface, and the tension portion in the working position abuts against the second surface.

[0012] A further improvement is that the tension portion, when in the working position, abuts against the junction of the second surface and the first surface.

[0013] A further improvement is as follows: the brush body includes a third surface relative to the second surface, the stop groove is disposed close to the first surface, and the distance between the stop groove and the first surface is smaller than the distance between the stop groove and the third surface.

[0014] A further improvement is as follows: the brush body is slidably connected to the brush holder, and the brush body moves upward so that the tension portion moves from the working position to the disassembly position.

[0015] A further improvement is as follows: the brush body is moved downward so that the tension portion moves from the disassembly position to the working position, and the tension portion increases the vertical force applied to the brush body and decreases the horizontal force applied to the brush body.

[0016] A further improvement is that the tension section is curved, and the movable end of the tension section faces away from the brush body.

[0017] A further improvement is that the stop groove is an arc-shaped groove.

[0018] This application provides a motor including the aforementioned brush assembly.

[0019] This application provides an electric tool, including the aforementioned motor.

[0020] The brush assembly, motor, and power tool provided in this application embodiment include: a brush holder; a brush body disposed on the brush holder, the surface of the brush body having a stop groove; and a spiral spring disposed on the brush holder, the spiral spring including a tension portion abutting against the brush body and a compression portion coiled around the brush holder, the tension portion including a working position and a disassembled position away from the working position, the tension portion being at least partially located in the stop groove in the disassembled position. This design facilitates modular assembly of the brush assembly, reduces rotor maintenance difficulty, and improves brush life. Attached Figure Description

[0021] One or more embodiments are illustrated by way of example with reference numerals in the accompanying drawings. These illustrations do not constitute a limitation on the embodiments. Elements with the same reference numerals in the drawings are denoted as similar elements. Unless otherwise stated, the figures in the drawings are not to be limited by scale.

[0022] Figure 1 This is a schematic diagram of the brush assembly structure at the corresponding disassembly / reassembly positions provided in some embodiments of this application;

[0023] Figure 2 This is a schematic diagram of the brush assembly structure at the corresponding working position provided in some embodiments of this application;

[0024] Figure 3 This is an exploded view of a brush assembly provided in some embodiments of this application;

[0025] Figure 4 These are schematic diagrams of the power tool structures provided in some embodiments of this application. Detailed Implementation

[0026] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the various embodiments of this application will be described in detail below with reference to the accompanying drawings. However, those skilled in the art will understand that many technical details have been presented in the various embodiments of this application to enable readers to better understand this application. However, even without these technical details and various changes and modifications based on the following embodiments, the technical solutions claimed in this application can be implemented. The division of the various embodiments below is for the convenience of description and should not constitute any limitation on the specific implementation of this application. The various embodiments can be combined with and referenced by each other without contradiction.

[0027] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used herein 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, in the specification, claims, and foregoing description of the drawings are intended to cover non-exclusive inclusion.

[0028] In the description of the embodiments of this application, unless otherwise expressly specified and limited, technical terms such as "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in the embodiments of this application according to the specific circumstances.

[0029] refer to Figures 1-3 The brush assembly 1 provided in some embodiments of this application includes a brush holder 10, a brush body 20, and a spiral spring 30. The brush body 20 is disposed on the brush holder 10, and its surface has a stop groove 24. As the basic support structure of the brush assembly 1, the brush holder 10 is typically made of metal or insulating material and is used to fix the brush body 20 and the spiral spring 30. The design of the brush holder 10 also needs to consider assembly compatibility with the motor housing. The brush body 20 is a conductive component slidably mounted within the brush holder 10, transmitting current through direct contact with the motor commutator. The stop groove 24 is designed on the surface of the brush body 20. The stop groove 24 is a groove located on the surface of the brush body 20, used to limit the tension portion 31 of the spiral spring 30 during assembly and disassembly, preventing it from rebounding.

[0030] A spiral spring 30, hereinafter referred to as a spring, is disposed on the brush holder 10. The spiral spring 30 includes a tension portion 31 that abuts against the brush body 20 and a compression portion 32 coiled around the brush holder 10. The tension portion 31 includes a working position and a disengaged position. In the disengaged position, the tension portion 31 is at least partially located in the stop groove 24. The spiral spring 30 has a dual-state design, including working and disengaged positions, which can correspond to the state of motor operation and rotor disassembly / removal. The tension portion 31 is a curved metal sheet that provides working pressure by abutting against the surface of the brush body 20. During disassembly / removal, the tension portion 31 slides into the stop groove 24 for temporary fixation. The compression portion 32 is a spring body coiled on the brush holder 10, which stores elasticity and can participate in adjusting the state switching of the tension portion 31. The working or disassembly / removal positions correspond to the spring state during normal brush operation and maintenance, respectively, and can be automatically switched by sliding the brush body 20 up and down. This design, through the cooperation of the stop groove 24 and the dual-state spring, solves the problem that traditional brushes require manual fixing of the spring during disassembly and assembly and cannot be assembled in modular form, significantly improving maintenance efficiency and the degree of modularity in assembly.

[0031] In one embodiment, the brush body 20 includes a first surface 21 and a second surface 22 adjacent to each other. A stop groove 24 is provided on the first surface 21, and the tension portion 31 in the working position abuts against the second surface 22. The first surface 21 is the working surface of the brush body 20 with the stop groove 24, and its arc-shaped groove design provides a spring positioning function during disassembly and assembly. The second surface 22 is a load-bearing surface adjacent to the first surface 21, and directly bears the pressure of the tension portion 31 of the spiral spring 30 in the working position, ensuring stable contact between the brush and the commutator. The stop groove 24 and the tension portion 31 form a spatial complementary relationship. In the working position, the spring abuts against the second surface 22, and during disassembly and assembly, it slides into the stop groove 24 of the first surface 21, realizing a dual-state switching of pressure release and positioning lock. This design, through surface partitioning and structural cooperation, maintains the stability of working pressure while providing an anchor point for spring fixation during maintenance, solving the problem of easy spring dislocation during disassembly and assembly of traditional brushes.

[0032] In one embodiment, the tension portion 31 in the working position abuts against the junction of the second surface 22 and the first surface 21. The junction refers to the boundary area between the first surface 21 (with a stop groove 24) and the second surface 22 (working bearing surface) of the brush body 20. This design places the contact point of the tension portion 31 of the spiral spring 30 in the transition zone between the two surfaces. By concentrating the spring pressure at the junction, stable contact pressure between the brush body 20 and the commutator is ensured in the working state, and a guiding transition is provided for the spring to slide into the stop groove 24 during disassembly and assembly. In another embodiment, the brush body 20 includes a third surface 23 opposite to the second surface 22. The stop groove 24 is located close to the first surface 21, and the distance between the stop groove 24 and the first surface 21 is smaller than the distance between the stop groove 24 and the third surface 23. The third surface 23 is the back surface of the brush body 20 opposite to the second surface 22. The layout of the stop groove 24 close to the first surface 21 shortens the spring displacement path and improves the state switching efficiency.

[0033] In one embodiment, the brush body 20 is slidably connected to the brush holder 10. Moving the brush body 20 upwards moves the tension portion 31 from the working position to the disassembly position. The slidable connection means that the brush body 20 and the brush holder 10 are axially movable, typically achieved through a guide rail or groove, allowing the brush body 20 to move in a direction perpendicular to the commutator surface. The upward movement of the brush body 20 corresponds to a maintenance operation; when the brush body 20 is lifted, the spatial position of the tension portion 31 of the spiral spring 30 is also changed. This upward movement causes the spring tension portion 31 to disengage from the second surface 22 and its adjacent portion, sliding along the first surface 21 into the stop groove 24. At this time, the downward pressure of the spring is released, and the brush can be safely disassembled. During the downward reset, the spring automatically slides back from the stop groove 24 to the working position, restoring the preset pressure. This design achieves reliable switching between two states through simple axial movement, ensuring pressure stability during operation and simplifying the maintenance process.

[0034] Furthermore, the downward movement of the brush body 20 moves the tension portion 31 from the disassembly position to the working position, increasing the vertical force exerted by the tension portion 31 on the brush body 20 and decreasing the horizontal force exerted on the brush body 20. Specifically, the increased vertical force includes: when the downward movement causes the spring tension portion 31 to slide from the stop groove 24 to the working position, the spring curvature increases, generating greater pressure to ensure tight contact between the brush and the commutator. The decreased horizontal force includes: the contact point between the spring and the brush body 20 transitions from the stop groove 24 to the aforementioned adjacent area or the second surface 22, avoiding lateral friction loss. This simultaneously solves the problems of insufficient pressure in the conventional brush assembly 1 leading to poor contact with the commutator and excessive lateral force causing brush vibration.

[0035] In one embodiment, the aforementioned tension portion 31 is curved, with its movable end facing away from the brush body 20. The curved shape refers to the continuous curvature structure of the spring tension portion 31. The curved shape of the tension portion 31 increases the elastic deformation stroke, making pressure adjustment more linear, and the outward expansion design of the movable end forms a mechanical lever, amplifying the efficiency of elastic potential energy conversion. Furthermore, the stop groove 24 is an arc-shaped groove. The arc-shaped groove and the curved shape of the tension portion 31 form a curved surface fit, providing a smooth transition path during assembly and disassembly, reducing spring wear.

[0036] To improve overall assembly efficiency and achieve a higher degree of componentization and modularization, a stop structure, the stop groove 24, is used to contact the tension portion 31 of the spiral spring 30 to achieve stopping, thereby enabling the integrated production of the brush, spiral spring 30, and brush holder 10 as a single component. During overall machine assembly, this integrated component is simply assembled into the motor housing or power tool housing, and the tension portion 31 of the spiral spring 30 is removed from the stop groove 24 of the brush. This componentized assembly process can be arranged before or after rotor installation, flexibly adapting to the pre- and post-assembly process arrangements of the motor or power tool.

[0037] The motor 2 provided in some embodiments of this application includes a motor shaft, a rotor assembly, a stator assembly and a commutator, and also includes the aforementioned brush assembly 1, wherein the brush body 20 of the brush assembly 1 is in contact with the commutator.

[0038] Further reference Figure 4 Some embodiments of this application also provide a power tool, which includes the motor 2 described above. The power tool can be a common handheld power tool, such as an electric screwdriver, electric grinder, or electric reciprocating saw. The power tool can also be a larger push-type tool, such as a lawnmower. The actuating component 3 of the power tool is driven by the motor 2 to perform the corresponding processing operations.

[0039] Those skilled in the art will understand that the above embodiments are specific implementations of this application, and in practical applications, various changes can be made in form and detail without departing from the spirit and scope of this application.

Claims

1. A brush assembly, characterized in that, include: Brush holder; A brush body is disposed on the brush holder, and a stop groove is provided on the surface of the brush body; A spiral spring is disposed on the brush holder. The spiral spring includes a tension portion that abuts against the brush body and a compression portion that is coiled around the brush holder. The tension portion includes a working position and a disassembled position that is out of the working position. When the tension portion is in the disassembled position, it is at least partially located in the stop groove.

2. The brush assembly according to claim 1, characterized in that: The brush body includes a first surface and a second surface that are adjacent to each other. The stop groove is provided on the first surface, and the tension portion in the working position abuts against the second surface.

3. The brush assembly according to claim 2, characterized in that: The tension portion, in the working position, abuts against the junction of the second surface and the first surface.

4. The brush assembly according to claim 2, characterized in that: The brush body includes a third surface opposite to the second surface, the stop groove is disposed close to the first surface, and the distance between the stop groove and the first surface is smaller than the distance between the stop groove and the third surface.

5. The brush assembly according to claim 1, characterized in that: The brush body is slidably connected to the brush holder, and the upward movement of the brush body causes the tension portion to move from the working position to the disassembly position.

6. The brush assembly according to claim 5, characterized in that: The downward movement of the brush body causes the tension portion to move from the disassembly position to the working position, and increases the vertical force applied to the brush body by the tension portion while decreasing the horizontal force applied to the brush body.

7. The brush assembly according to claim 1, characterized in that: The tension section is curved, and the movable end of the tension section faces away from the brush body.

8. The brush assembly according to claim 1, characterized in that: The stop groove is an arc-shaped groove.

9. An electric motor, characterized in that: Includes the brush assembly as described in any one of claims 1 to 8.

10. A power tool, characterized in that: Includes the motor as described in claim 9.

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