Miniaturized high-torque brush motor

Abstract

The utility model discloses a miniaturized high moment has brush motor, this motor aims at solving the inductance element and carbon brush assembly and terminal of existing motor inside adopt direct welding mode, cannot keep reliable contact in the problem of vibration environment. The motor includes the shell, the stator subassembly of fixed mounting in the shell inside, the rotor subassembly of rotation installation in the shell inside and with the terminal subassembly of rotor subassembly electricity is connected, and the terminal subassembly includes the middle plate, installs the inductance in the middle plate, carbon brush assembly and conducting terminal, and one end of inductance is fixed after welding with the conducting terminal riveting, and the other end of inductance is fixed after welding with carbon brush assembly riveting. The utility model passes through independent riveting welding inductance both ends, realizes inductance and brush arm, inductance and the high strength mechanical locking and conducting connection of conducting terminal, and the anti -vibration performance is superior to direct welding mode, can keep reliable contact in the vibration environment.

Description

Technical Field

[0001] This utility model belongs to the field of brushed DC motor technology, specifically relating to a miniaturized high-torque brushed motor. Background Technology

[0002] DC brushed motors are widely used in power tools, electric vehicles, industrial automation, and other fields due to their simple structure and convenient control. Their working principle involves switching the current direction through the contact between the brushes and the commutator, thereby driving the rotor to rotate continuously. However, the connection between the inductor components, carbon brush assemblies, and terminals inside existing motors is mostly achieved through direct soldering. This connection occupies a large space and carries the risk of poor soldering under vibration conditions, failing to maintain reliable contact in a vibrating environment. Utility Model Content

[0003] (1) Technical problems to be solved To address the shortcomings of existing technologies, the purpose of this invention is to provide a miniaturized high-torque brushed motor. This motor aims to solve the problem that existing motors use direct welding of the inductor components, carbon brush assemblies, and terminals, which makes it impossible to maintain reliable contact in a vibration environment.

[0004] (2) Technical solution To solve the above-mentioned technical problems, this utility model provides a miniaturized high-torque brushed motor, which includes a housing, a stator assembly fixedly installed inside the housing, a rotor assembly rotatably installed inside the housing, and a terminal assembly electrically connected to the rotor assembly. The terminal assembly includes a middle plate, an inductor, a carbon brush assembly, and conductive terminals installed in the middle plate. One end of the inductor is riveted to the conductive terminal and then welded to fix it, and the other end of the inductor is riveted to the carbon brush assembly and then welded to fix it.

[0005] Preferably, the thickness of the magnet in the stator assembly is 2.0 mm, the air gap length between the stator assembly and the rotor assembly is 0.4 mm, the pole arc coefficient of the motor is 0.8 mm, and the magnet in the stator assembly is made of high coercivity rare earth permanent magnet material.

[0006] Furthermore, the carbon brush assembly includes a brush arm and a carbon brush body. One end of the brush arm is fixedly connected to the inner wall of the middle plate, and a first rivet is fixedly connected to the brush arm. The carbon brush body is installed at the other end of the brush arm.

[0007] Furthermore, one end of the conductive terminal is located outside the middle plate, and the other end of the conductive terminal is located inside the middle plate, with the end of the conductive terminal located inside the middle plate being fixedly connected to the second riveting component.

[0008] Furthermore, the brush arm is made of silver-plated copper alloy or nickel-plated steel.

[0009] Furthermore, the brush arm is bent, and there are two carbon brushes and two inductors. The two carbon brushes are located between the conductive terminals and the rotor assembly, respectively, and the two inductors are located between the brush arm and the rotor assembly, respectively.

[0010] Furthermore, two mounting slots are provided on the upper and lower sides of the middle plate, and two mounting holes are provided on the left and right sides of the middle plate. There are two brush arms and two conductive terminals. The brush arm includes a mounting part and an elastic part. The two mounting parts are fixedly connected in the two mounting slots, and the two conductive terminals are fixedly connected in the two mounting holes.

[0011] ( ) beneficial effects Compared with the prior art, the beneficial effects of this utility model are as follows: 1. This utility model achieves high-strength mechanical locking and conductive connection between the inductor and the brush arm, and between the inductor and the conductive terminal by independently press-fitting the two ends of the inductor. The vibration resistance is better than that of the direct welding method, and reliable contact can be maintained in a vibrating environment. 2. This utility model redesigns the inductor, carbon brush assembly, and conductive terminals within the middle plate. While maintaining rigidity, it adjusts the installation positions of the brush arms and inductors, thereby improving the utilization rate of the internal space of the motor and increasing the power density. Furthermore, the inductor's placement closer to the center shortens the electrical connection path between it and the brush arms and conductive terminals, reducing wire length and solder usage. This results in a more uniform distribution of internal heat sources, which helps reduce temperature rise and makes the motor more efficient under high loads. Attached Figure Description

[0012] Figure 1 This is a schematic diagram of the motor structure of this utility model.

[0013] Figure 2 This is a schematic diagram of the cross-sectional structure of the motor of this utility model.

[0014] Figure 3 This is a structural schematic diagram of the terminal assembly of this utility model.

[0015] Figure 4 This is a schematic diagram of the connection structure of the inductor of this utility model.

[0016] Figure 5 This is a schematic diagram of the structure of the middle plate of this utility model.

[0017] The labels in the attached drawings are as follows: 1. Housing; 2. Stator assembly; 3. Rotor assembly; 4. Terminal assembly; 5. Middle plate; 6. Inductor; 7. Carbon brush assembly; 8. Conductive terminal; 701. Brush arm; 702. Carbon brush body; 703. First riveting member; 801. Second riveting member; 501. Mounting groove; 502. Mounting hole; 7011. Mounting part; 7012. Elastic part. Detailed Implementation

[0018] This specific embodiment is a miniaturized high-torque brushed motor, and its structural schematic diagram is shown below. Figures 1-5 As shown, the motor includes a housing 1, a stator assembly 2 fixedly installed inside the housing 1, a rotor assembly 3 rotatably installed inside the housing 1, and a terminal assembly 4 electrically connected to the rotor assembly 3. The structures of the stator assembly 2 and the rotor assembly 3 are existing technologies and will not be described in detail here. A gearbox is installed at the output end of the stator assembly 2. The terminal assembly 4 includes a middle plate 5, an inductor 6 installed in the middle plate 5, a carbon brush assembly 7, and a conductive terminal 8. One end of the inductor 6 is riveted to the conductive terminal 8 and then welded to fix it, and the other end of the inductor 6 is riveted to the carbon brush assembly 7 and then welded to fix it. The above-mentioned brushed motor relates to a small high-torque motor and its internal component connection structure that achieves higher performance than conventional size motors under the condition of an outer diameter of 25mm through magnetic circuit optimization and spatial structure improvement.

[0019] To ensure a more secure weld after inductor 6 is soldered, such as Figure 3 and Figure 4 As shown: In this embodiment, the carbon brush assembly 7 includes a brush arm 701 and a carbon brush body 702. One end of the brush arm 701 is fixedly connected to the inner wall of the middle plate 5, and a first riveting member 703 is fixedly connected to the brush arm 701. The carbon brush body 702 is installed at the other end of the brush arm 701. The middle plate 5 is made of insulating material, or there is an insulating layer between the brush arm 701 and the inner wall of the middle plate 5. The brush arm 701 is elastic, allowing the carbon brush body 702 to slide in contact with the brush ring on the rotor assembly 3. One end of the conductive terminal 8 is located outside the middle plate 5. The other end is located inside the middle plate 5, and the conductive terminal 8 is fixedly connected to the second riveting member 801 at one end inside the middle plate 5. The middle plate 5 is made of insulating material, or there is an insulating layer between the conductive terminal 8 and the inner wall of the middle plate 5. It is welded to the inductor after being riveted by the first riveting member 703 and the second riveting member 801, thereby avoiding direct welding, reducing thermal stress and space occupation. The first riveting member 703 and the second riveting member 801 are bent, and there are two of each, which can better weld to the inductor 6 after being riveted, reduce the amount of solder used, and maintain reliable contact in a vibration environment.

[0020] In this embodiment, the brush arm 701 is a silver-plated copper alloy or a nickel-plated steel part, which ensures the conductivity of the brush arm 701 and also has the functions of vibration resistance and anti-loosening.

[0021] To reduce the length of the wire, such as Figure 3 and Figure 4As shown: In this embodiment, the brush arm 701 is bent, and there are two carbon brushes 702 and two inductors 6. The two carbon brushes 702 are located between the conductive terminal 8 and the rotor assembly 3, respectively, and the two inductors 6 are located between the brush arm 701 and the rotor assembly 3, respectively. Since the brush arm 701 is bent and approximately at a right angle, the brush arm 701 is installed on the upper and lower sides of the middle plate 5. At this time, the carbon brushes 702 are installed on the left and right sides of the middle plate 5. Meanwhile, the inductors 6 are arranged close to the center, which shortens the electrical connection path between the inductors 6 and the brush arm 701 and the conductive terminal 8, reduces the wire length, and makes the motor have a lower temperature rise and higher efficiency under high load.

[0022] To make it easier to fix the brush arm 701 and the conductive terminal 8, such as Figure 3 and Figure 5 As shown: In this embodiment, two mounting grooves 501 are opened on the upper and lower sides of the middle plate 5, and two mounting holes 502 are opened on the left and right sides of the middle plate 5. There are two brush arms 701 and two conductive terminals 8. The brush arm 701 includes a mounting part 7011 and an elastic part 7012. The two mounting parts 7011 are fixedly connected in the two mounting grooves 501, and the two conductive terminals 8 are fixedly connected in the two mounting holes 502. The mounting part 7011 and the elastic part 7012 are metal sheet structures.

[0023] Because the output torque of existing brushed DC motors with a small outer diameter of 25mm is limited by the magnetic circuit cross-sectional area and internal space, in order to achieve high torque output, it is usually necessary to increase the outer diameter to 28mm or larger, which will increase the overall size of the machine and is not conducive to miniaturization applications. To achieve an output torque comparable to a 28mm outer diameter motor, such as Figure 1 and Figure 2 As shown: In this embodiment, the thickness of the magnet of stator assembly 2 is A, A=2.0mm, the air gap length between stator assembly 2 and rotor assembly 3 is B, B=0.4mm, the pole arc coefficient of the motor is 0.8mm, and the magnet of stator assembly 2 is made of high coercivity rare earth permanent magnet material.

[0024] By adjusting the magnet thickness, pole arc coefficient, and air gap length in a 25mm outer diameter motor, the pole arc coefficient is a parameter representing the ratio of pole arc length to pole pitch. By optimizing the motor's pole arc coefficient to 0.8, the magnet thickness is changed from 3.0mm to 2.0mm, and the air gap length is changed from 0.5mm to 0.4mm. High-performance magnetic ring materials, such as high-coercivity rare-earth permanent magnet materials, are used to increase magnetic flux density, optimize the magnetic circuit closed path, reduce magnetic leakage, and improve the effective magnetic flux utilization rate, achieving an output torque comparable to a 28mm outer diameter motor. The optimized structure reduces the excess space inside the motor, allowing the motor length to range from 50-68mm. The rotor assembly 3 and stator assembly 2 can be arranged in a more compact housing 1, thereby further improving power density. like Figure 1 and Figure 2 As shown: The output end of stator assembly 2 is equipped with a gearbox. Originally, it was a 28 motor with a 24 gearbox. This utility model optimizes it so that a 25 motor can also be equipped with a 24 gearbox, and can achieve the effect of a 28 motor, freeing up more space in the whole machine for other parts.

[0025] All technical features in this embodiment can be freely combined according to actual needs.

[0026] The above embodiments are preferred implementations of this utility model. In addition, this utility model can also be implemented in other ways. Any obvious substitutions without departing from the concept of this technical solution are within the protection scope of this utility model.

Claims

1. A miniaturized high torque brush motor, the motor comprising a housing (1), a stator assembly (2) fixedly installed inside the housing (1), a rotor assembly (3) rotatably installed inside the housing (1), and a terminal assembly (4) electrically connected with the rotor assembly (3), characterized in that: The terminal assembly (4) includes a middle plate (5), an inductor (6) installed in the middle plate (5), a carbon brush assembly (7) and a conductive terminal (8). One end of the inductor (6) is pressed and welded to the conductive terminal (8), and the other end of the inductor (6) is pressed and welded to the carbon brush assembly (7).

2. The downsized high-torque brush motor according to claim 1, wherein The thickness of the magnet in the stator assembly (2) is 2.0 mm, the air gap length between the stator assembly (2) and the rotor assembly (3) is 0.4 mm, the pole arc coefficient of the motor is 0.8 mm, and the magnet in the stator assembly (2) is made of high coercivity rare earth permanent magnet material.

3. The miniaturized high-torque brush motor of claim 1, wherein, The carbon brush assembly (7) includes a brush arm (701) and a carbon brush body (702). One end of the brush arm (701) is fixedly connected to the inner wall of the middle plate (5), and a first rivet (703) is fixedly connected to the brush arm (701). The carbon brush body (702) is installed at the other end of the brush arm (701).

4. The miniaturized high-torque brush motor according to claim 3, wherein One end of the conductive terminal (8) is located outside the middle plate (5), and the other end of the conductive terminal (8) is located inside the middle plate (5). The end of the conductive terminal (8) located inside the middle plate (5) is fixedly connected to the second riveting member (801).

5. The miniaturized high-torque brush motor according to claim 4, wherein The brush arm (701) is a silver-plated copper alloy or a nickel-plated steel.

6. The miniaturized high-torque brush motor according to claim 5, wherein The brush arm (701) is bent, and there are two carbon brushes (702) and two inductors (6). The two carbon brushes (702) are located between the conductive terminal (8) and the rotor assembly (3), respectively, and the two inductors (6) are located between the brush arm (701) and the rotor assembly (3).

7. The miniaturized high-torque brush motor according to claim 6, wherein The middle plate (5) has two mounting slots (501) on its upper and lower sides, and two mounting holes (502) on its left and right sides. The brush arm (701) and the conductive terminal (8) are both two in number. The brush arm (701) includes a mounting part (7011) and an elastic part (7012). The two mounting parts (7011) are fixedly connected in the two mounting slots (501), and the two conductive terminals (8) are fixedly connected in the two mounting holes (502).

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