A DC motor electromagnetic disturbance resistance system and assembly method thereof

Abstract

The present invention relates to the technical field of direct current motors, and more specifically, to a direct current motor electromagnetic disturbance resistance system and an assembly method thereof, wherein the electromagnetic disturbance resistance system comprises a PCB board and an inductor having an equal number to a commutator segment, a plurality of inductors are fixedly mounted on the PCB board along a second circumference, and two terminals of the same inductor are respectively electrically connected to two adjacent commutator segments, the commutator segment is fixedly connected to the PCB board, and the commutator segment and the inductor are respectively mounted on two opposite sides of the PCB board; the assembly method comprises the steps of connecting the inductor to the PCB board and connecting the commutator segment to the PCB board. The present invention electrically connects the inductor between two adjacent commutator segments, and utilizes the principle of inductor filtering to effectively prevent the sudden change of current when the brush passes through the commutator segment gap; there is no need to change the structural design of the conventional direct current motor commutator segment, and only the PCB board needs to be connected and installed on the original commutator segment, so the processing difficulty is small, the processing cost is low, the assembly operation difficulty is low, it is easy to implement, and the application range is wide.

Description

Technical Field

[0001] The present invention relates to the technical field of direct current motors, and more specifically, to a direct current motor electromagnetic disturbance resistance system and an assembly method thereof. Background Art

[0002] Electromagnetic interference is an electromagnetic phenomenon that may cause the performance of devices or systems to deteriorate. It is the noise emitted by electrical products. Ordinary motors without specific requirements have no ability to resist electromagnetic interference. During the operation of the motor, the electromagnetic interference generated by the commutation process is more prominent. Specifically, the electromagnetic interference generated by the commutation process mainly comes from the following three sources: 1. During the operation of the motor, commutation sparks are generated when the carbon brush contacts different commutation segments for commutation; 2. The rotor current and electromotive force of the motor pulsate during the commutation process, causing harmonic interference; 3. The motor generates harmonic distortion during the commutation process, which generates electromagnetic interference to other equipment.

[0003] In order to avoid electromagnetic interference generated during the commutation process, a variety of solutions have been adopted in the prior art. For example, Chinese patent CN106329838A discloses a method and structure for suppressing electromagnetic interference of a DC motor commutator, in which a capacitor is installed between two commutator segments to absorb the electromagnetic interference generated by the commutator. The electromagnetic interference suppression structure is to form a groove on the inner side of the commutator segment at one end of the commutator, and the chip capacitors are placed at an equal distance between every two commutator segments, and the reflow soldering process is used for welding. Although the above structure and method absorb the electromagnetic interference generated by the commutator by connecting capacitors between the commutator segments, the above structure and method change the shape structure of the conventional commutator segment for installing the capacitor, increase the difficulty of processing, and increase the processing cost. In addition, since the size of the chip capacitor is very small, it is difficult to weld the chip capacitor between the two commutator segments. Summary of the invention

[0004] The purpose of the present invention is to overcome the shortcomings of the prior art, such as high processing difficulty, high processing cost and difficult assembly operation, and to provide a DC motor electromagnetic disturbance resistance system and an assembly method thereof, which have low processing difficulty, low processing cost and low assembly operation difficulty, are easy to implement and have a wide range of applications.

[0005] In order to solve the above technical problems, the technical solution adopted by the present invention is:

[0006] Provided is a DC motor electromagnetic disturbance resistance system, the DC motor comprising a carbon brush and a plurality of commutator segments which rotate and contact with the carbon brushes to realize commutation, the plurality of commutator segments being arranged around a first circumference; the electromagnetic disturbance resistance system comprising a PCB board and an inductor having an equal number to the commutator segments, the plurality of inductors being fixedly mounted on the PCB board around a second circumference, and two terminals of the same inductor being respectively electrically connected to two adjacent commutator segments, the commutator segments being fixedly connected to the PCB board, and the commutator segments and the inductor being respectively mounted on two opposite sides of the PCB board.

[0007] The DC motor electromagnetic disturbance resistance system of the present invention electrically connects the inductor between two adjacent commutator segments, and utilizes the principle of inductor filtering to effectively prevent the sudden change of current when the brush passes through the gap between the commutator segments. The commutator segments and the inductor of the present invention are respectively installed on two opposite sides of the PCB board, which is convenient for the connection and installation of the PCB board and the commutator segments, and also convenient for the connection and installation of the inductor and the PCB board. The present invention does not need to change the structural design of the conventional DC motor commutator segments, and only needs to connect and install the PCB board on the original commutator segments. It is not only suitable for the new series of anti-interference DC motors, but also suitable for the transformation of non-interference design DC motors. It has low processing difficulty, low processing cost, low assembly operation difficulty, is easy to implement, and has a wide range of applications.

[0008] Furthermore, a winding portion is provided at the bottom of the commutator segment, and a mounting hole is provided on the PCB board for the winding portion to pass through. After passing through the mounting hole, the winding portion is bent toward a side close to the inductor to form a winding hook angle; the second circumference is arranged concentrically with the first circumference and the diameter of the second circumference is larger than the diameter of the first circumference, and the two terminals of the inductor are electrically connected to two adjacent winding hook angles respectively. After the winding portion passes through the mounting hole and is bent, not only a winding hook foot can be obtained, but also a quick connection between the PCB board and the commutator segment can be achieved.

[0009] Furthermore, the PCB board is provided with a positioning groove, one end of the winding part passing through the mounting hole is clamped in the positioning groove, and a plurality of the positioning grooves are arranged around the third circumference, the third circumference is arranged concentrically with the second circumference and the first circumference, and the diameter of the third circumference is between the diameter of the first circumference and the diameter of the second circumference; the two opposite groove walls of the positioning groove are trapezoids whose cross-sectional dimensions gradually increase from top to bottom; the two opposite groove walls of the positioning groove are provided with a first pad electrically connected to the inductor, and the first pad is inscribed in the trapezoid. The clamping connection between the end of the winding part and the positioning groove is used to improve the connection stability between the PCB board and the commutator segment, and to avoid the relative offset between the two during the high-speed operation of the motor rotor, which affects the working safety of the motor; the design of the first pad enables the electrical connection between the inductor and the commutator segment to be achieved while the winding part is clamped into the positioning groove, which is convenient and quick.

[0010] Furthermore, the PCB board is a circular ring structure, the bottom of the commutator segment is provided with a winding portion, the winding portion is provided between the commutator segment and the inner ring surface of the circular ring structure; the winding portion is connected to the PCB board through a second pad, the terminals of two adjacent inductors are electrically connected through a third pad, and the second pad is electrically connected to the third pad. The connection between the commutator segment and the PCB board does not need to be achieved by opening a hole in the PCB board, the structure of the PCB board is simpler, and the production cost is lower.

[0011] Furthermore, a first positioning structure for radial positioning and a second positioning structure for axial positioning are provided between the PCB board and the commutator segment, and both the first positioning structure and the second positioning structure are provided on the PCB board. The radial displacement is limited by the first positioning structure, and the axial displacement is limited by the second positioning structure, so as to improve the connection stability between the commutator segment and the PCB board, and avoid relative displacement between the motor rotor and the PCB board during high-speed operation, which affects the working safety of the motor.

[0012] Furthermore, the DC motor is connected to the positive and negative poles of the power supply through a power connector to form a loop, and the two ends of the power connector are respectively a first connection part and a second connection part, the first connection part includes a first plug and a second plug arranged side by side, and the second connection part includes a first terminal and a second terminal arranged side by side, the first terminal is connected to the negative pole of the power supply through the first plug, and the second terminal is connected to the positive pole of the power supply through the second plug, and a filter capacitor is provided between the second plug and the second terminal. The setting of the filter capacitor can filter out differential mode and common mode noise, ensuring that the power grid is free from the pollution of the internal noise of the product.

[0013] Furthermore, the second connection portion further includes a third terminal arranged side by side with the first terminal and the second terminal, the third terminal being arranged between the second terminal and the first terminal, one pin of the filter capacitor being electrically connected to the third terminal, and another pin of the filter capacitor being electrically connected to the second terminal. The third terminal is added to achieve power supply filtering and facilitate the installation and fixation of the filter capacitor.

[0014] Furthermore, the second connection portion includes a first wiring cavity, a third wiring cavity and a second wiring cavity arranged side by side, and the first terminal, the second terminal and the third terminal are respectively located in the first wiring cavity, the second wiring cavity and the third wiring cavity; the third wiring cavity and the second wiring cavity are separated by a T-shaped support platform, and a capacitor placement cavity connected to the third wiring cavity and the second wiring cavity is provided above the T-shaped support platform. The T-shaped support platform is used to support the filter capacitor, and the capacitor placement cavity provides an installation space for the filter capacitor. The capacitor placement cavity is connected to the third wiring cavity and the second wiring cavity to facilitate welding the two pins of the filter capacitor to the second terminal and the third terminal, respectively.

[0015] Furthermore, the DC motor also includes an end cap, the carbon brush is installed on a carbon brush holder, a first installation slot for installing a first filter capacitor and a second installation slot for installing a second filter capacitor are provided in the carbon brush holder, a first grounding hole connected to the first installation slot and a second grounding hole connected to the second installation slot are provided on the side wall of the carbon brush holder, one pin of the first filter capacitor is electrically connected to the positive wire, and the other pin passes through the first grounding hole to contact the end cap for grounding, and one pin of the second filter capacitor is electrically connected to the negative wire, and the other pin passes through the second grounding hole to contact the end cap for grounding. By using the grounding method, the interference can be isolated and reduced so that it is no longer conducted outward through the power line to solve the problem of electromagnetic interference.

[0016] The present invention also provides an assembly method of a DC motor electromagnetic disturbance resistance system, comprising the following steps:

[0017] S10 provides a ring-shaped PCB board, and a plurality of inductors are welded and fixed along the second circumference on the first side of the PCB board, the number of the inductors being equal to the number of the commutator segments;

[0018] S20. The commutator segments are fixedly connected to the second side surface of the PCB board, and two terminals of the same inductor are electrically connected to two adjacent commutator segments respectively; the first side surface and the second side surface are two opposite side surfaces of the PCB board.

[0019] The assembly method of the direct current motor electromagnetic disturbance resistance system of the present invention electrically connects the inductor between two adjacent commutator segments, and utilizes the principle of inductor filtering to effectively prevent the sudden change of current when the brush passes through the gap between the commutator segments; the commutator segments and the inductor are respectively installed on two opposite sides of a PCB board, which is convenient for connecting and installing the PCB board and the commutator segments, and also convenient for connecting and installing the inductor and the PCB board; there is no need to change the structural design of the conventional direct current motor commutator segments, and only needs to connect and install the PCB board on the original commutator segments. The method is not only suitable for a new series of anti-interference direct current motors, but also suitable for the transformation of direct current motors with non-interference design, has low processing difficulty, low processing cost, low assembly operation difficulty, is easy to implement, and has a wide range of applications. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a structural schematic diagram of a DC motor electromagnetic disturbance resistance system from one perspective in the first embodiment;

[0021] Figure 2 It is a structural schematic diagram of the DC motor electromagnetic disturbance resistance system from another perspective in the first embodiment;

[0022] Figure 3 is a schematic diagram of the positioning groove and the first pad in the first embodiment;

[0023] Figure 4The circuit schematic diagram of the DC motor electromagnetic disturbance resistance system in Embodiment 1 and Embodiment 2;

[0024] Figure 5 This is a structural diagram of a DC motor electromagnetic disturbance resistance system from one perspective in Example 2;

[0025] Figure 6 This is a schematic diagram of the structure of a PCB board of a DC motor electromagnetic disturbance resistance system in Example 2;

[0026] Figure 7 This is a schematic diagram of the structure of the mounting platform of the DC motor electromagnetic disturbance resistance system in Example 2;

[0027] Figure 8 It is a structural schematic diagram of a positioning platform of a DC motor electromagnetic disturbance resistance system in Embodiment 2;

[0028] Fig. 9 This is a structural diagram of a DC motor electromagnetic disturbance resistance system from one perspective in Example 3;

[0029] Fig.10 This is a schematic structural diagram of the DC motor electromagnetic disturbance resistance system from another perspective in Example 3;

[0030] Fig.11 The schematic diagram of the circuit of the DC motor electromagnetic disturbance resistance system in the third embodiment;

[0031] Fig.12 This is a structural diagram of a DC motor electromagnetic disturbance resistance system from one perspective in Embodiment 4;

[0032] Fig.13 It is a structural schematic diagram of another perspective of the DC motor electromagnetic disturbance resistance system in the fourth embodiment;

[0033] Fig.14 The circuit schematic diagram of the DC motor electromagnetic disturbance resistance system in the fourth embodiment;

[0034] In the accompanying drawings: 100, carbon brush; 200, commutator segment; 210, winding part; 300, PCB board; 310, positioning groove; 320, first pad; 330, second pad; 340, third pad; 350, mounting platform; 360, positioning platform; 361, connecting part; 362, positioning part; 400, inductor; 500, power connector; 510, first connecting part; 511, first plug; 512, second plug; 520, second connecting part; 521, first terminal; 522, second terminal; 5 23. The third terminal; 524. The first wiring cavity; 525. The second wiring cavity; 526. The third wiring cavity; 527. The T-shaped support platform; 528. The capacitor placement cavity; 530. The filter capacitor; 600. The carbon brush holder; 610. The shell; 611. The first mounting groove; 612. The second mounting groove; 613. The first grounding hole; 614. The second grounding hole; 615. The positive wire; 616. The negative wire; 617. The power cord; 618. The first interface; 620. The first filter capacitor; 630. The second filter capacitor. DETAILED DESCRIPTION

[0035] The present invention is further described below in conjunction with specific implementation methods. The accompanying drawings are only used for exemplary descriptions and are only schematic diagrams, not actual drawings, and cannot be understood as limiting this patent; in order to better illustrate the embodiments of the present invention, some parts of the accompanying drawings may be omitted, enlarged or reduced, and do not represent the size of the actual product; for those skilled in the art, it is understandable that some well-known structures and their descriptions in the accompanying drawings may be omitted.

[0036] The same or similar numbers in the drawings of the embodiments of the present invention correspond to the same or similar parts; in the description of the present invention, it should be understood that if the terms "upper", "lower", "left", "right" and the like indicate directions or positional relationships based on the directions or positional relationships shown in the drawings, it is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, the terms describing the positional relationship in the drawings are only used for illustrative purposes and cannot be understood as limitations on this patent. For ordinary technicians in this field, the specific meanings of the above terms can be understood according to specific circumstances.

[0037] Embodiment 1

[0038] This embodiment is the first embodiment of the DC motor electromagnetic disturbance resistance system of the present invention. The DC motor includes a carbon brush 100 and a plurality of commutator segments 200 that rotate and contact with the carbon brush 100 to achieve commutation. The plurality of commutator segments 200 are arranged around a first circumference. The electromagnetic disturbance resistance system includes a PCB board 300 and an inductor 400 equal in number to the commutator segments 200. The plurality of inductors 400 are fixedly installed on the PCB board 300 around a second circumference and the two terminals of the same inductor 400 are respectively electrically connected to two adjacent commutator segments 200. The commutator segments 200 are fixedly connected to the PCB board 300. The commutator segments 200 and the inductor 400 are respectively installed on two opposite sides of the PCB board 300. Figure 1 , Figure 2 As shown. The first circumference is the circular path where the commutator segments 200 are located, and the second circumference is the circular path where the center line of the inductor 400 is located. In the cross-sectional direction, the inductor 400 is evenly distributed on the second circumference; in the longitudinal cross-sectional direction, the inductor 400 is arranged opposite to the commutation slot between the two commutator segments 200, that is, the width of the inductor 400 on both sides of the commutation slot is equal.

[0039] The commutator segment 200 is provided with a winding portion 210 at the bottom, and the PCB board 300 is provided with a mounting hole for the winding portion 210 to pass through; in order to achieve stable installation of the winding portion 210 and the mounting hole, the opening size of the mounting hole in this embodiment is close to the cross-sectional size of the winding portion 210, so that the winding portion 210 can be clamped in the mounting hole, and the winding portion 210 and the PCB board 300 can be quickly connected while ensuring the connection stability between the two. After passing through the mounting hole, the winding portion 210 is bent toward the side close to the inductor 400 to form a winding hook angle, and the armature winding is electrically connected to the commutator segment 200 to form a loop to ensure the normal operation of the motor; in order to facilitate the winding portion 210 to be quickly bent at a certain set position to form a winding hook angle, the winding portion 210 of this embodiment can be provided with a folding portion to facilitate the bending operation, and the winding portions 210 of different groups are bent to the same or similar degree at the same position, which can effectively ensure the structural symmetry of the overall device. The second circle is concentrically arranged with the first circle and the diameter of the second circle is greater than the diameter of the first circle. After passing through the mounting hole, the winding portion 210 is bent toward the side close to the inductor 400 to form a winding hook angle, so as to facilitate the winding portion to approach the wiring terminals of the inductor 400 to be electrically connected to the two wiring terminals of the inductor 400.

[0040] In addition, in this embodiment, the winding part 210 is a bendable and deformable elastic sheet structure, the PCB board 300 is provided with a positioning groove 310, one end of the winding part 210 passing through the mounting hole is clamped in the positioning groove 310, and a plurality of the positioning grooves 310 are arranged around the third circumference, the third circumference is arranged concentrically with the second circumference and the first circumference, and the diameter of the third circumference is between the diameter of the first circumference and the diameter of the second circumference, and the third circumference is a circular path where the center line of the positioning groove 310 is located. The third circumference is between the first circumference and the second circumference, which facilitates the free end of the winding part 210 to be clamped into the positioning groove 310, and also facilitates the electrical connection of the winding part 210 clamped in the positioning groove 310 with the terminal of the inductor 400. The two opposite groove walls of the positioning groove 310 are trapezoidal in shape, with the cross-sectional dimensions gradually increasing from top to bottom, so as to prevent the winding portion 210 from slipping out of the positioning groove 310; the two opposite groove walls of the positioning groove 310 are provided with a first soldering pad 320 electrically connected to the inductor 400, and the first soldering pad 320 is inscribed in the trapezoid, at least tangent to the top and bottom sides of the trapezoid, such as Figure 3 As shown; the design of the first pad 320 and its shape and size allows the electrical connection between the inductor 400 and the commutator segment 200 to be achieved while the winding portion 210 is inserted into the positioning groove 310, without the need for additional electrical connection operations, which is convenient and quick.

[0041] The specific implementation process of this embodiment is as follows:

[0042] When the carbon brush 100 in contact with the surface of the rotating commutator segment 200 slides from the previous commutator segment 200 through the commutator segment slot to the next commutator segment 200, the two adjacent commutator segments 200 are turned on at the same time. At this time, the inductor 400 between the two adjacent commutator segments 200 is also turned on, which plays a role in suppressing the instantaneous current mutation and generating interference noise at the moment of commutation, such as Figure 4 As shown. In this embodiment, the connection stability between the PCB board 300 and the commutator segment 200 is improved by multiple connections: the clamping connection between the winding portion 210 and the mounting hole, the clamping connection between the end of the winding portion 210 and the positioning groove 310, and the welding between the commutator segment 200 and the PCB board 300. In addition to the stable connection, the commutator segment 200, the inductor 400, the mounting hole, the positioning groove 310, the solder joint, the PCB board 300, etc. are all arranged symmetrically around the center of the axis of the PCB board 300, so as to avoid adverse effects on the dynamic balance of the DC motor running at high speed.

[0043] Embodiment 2

[0044] This embodiment is the second embodiment of the DC motor electromagnetic disturbance resistance system of the present invention. This embodiment is similar to the first embodiment, except that the PCB board 300 is a circular ring structure, the diameter of the inner ring of the circular ring structure is greater than the diameter of the first circumference; and the bottom of the circular ring commutator segment 200 is provided with a winding portion 210, the winding portion 210 is provided between the commutator segment 200 and the inner ring wall of the circular ring structure, and the two opposite side surfaces of the winding portion 210 are respectively in contact with the inner ring wall of the circular ring structure and the surface of the commutator segment 200, as shown in FIG. Figure 5 The winding portion 210 is connected to the PCB board 300 through the second pad 330, as shown Figure 5 The terminals of two adjacent inductors 400 are electrically connected via a third pad 340, as shown. Figure 6 As shown, the second pad 330 is electrically connected to the third pad 340. The connection between the commutator 200 and the PCB board 300 does not need to be realized by drilling a hole on the PCB board 300, and the structure of the PCB board 300 is simpler and the production cost is lower.

[0045] The connection between the commutator segment 200 and the PCB board 300 is achieved by multiple weldings between the winding portion 210 and the PCB board 300. Although this can meet the needs of some usage scenarios, since the winding portion 210 is a thin film structure and the commutator segment 200 is an arc structure, the contact between the thin film structure and the arc structure is a line contact. The thin film winding portion 210 is prone to relative position displacement with the commutator segment 200, thereby having an adverse effect on the dynamic balance of the motor during operation.

[0046] In order to further improve the connection stability between the commutator segment 200 and the PCB board 300 and prevent the relative position between the two from shifting during high-speed operation, a first positioning structure for radial positioning and a second positioning structure for axial positioning are provided between the PCB board 300 and the commutator segment 200, and the first positioning structure and the second positioning structure are both provided on the PCB board 300. When this embodiment is implemented, the radial displacement is limited by the first positioning structure, and the axial displacement is limited by the second positioning structure, so as to improve the connection stability between the commutator segment 200 and the PCB board 300, and prevent the relative shift between the two during high-speed operation of the motor rotor, which affects the working safety of the motor.

[0047] Specifically, the first positioning structure is a plurality of mounting platforms 350 disposed on the inner ring of the PCB board 300, wherein the plurality is at least three and the plurality of mounting platforms 350 are evenly distributed, such as Figure 7As shown. The thickness of the mounting platform 350 is equal to the thickness of the PCB board 300, and the mounting platform 350 can be integrally formed with the PCB board 300. The top and bottom surfaces of the mounting platform 350 are flush with the upper and lower side surfaces of the PCB board 300, and there are three peripheral side surfaces between the bottom and top surfaces, and the three peripheral side surfaces are respectively in contact with the outer peripheral surface of the commutator segment 200, the side surface of the winding hook foot, and the side surface of the adjacent winding hook foot. With such a configuration, when the commutator segment 200 is installed with the PCB board 300, the gap between the mounting platform 350 and the adjacent commutator segment 200 is aligned and the mounting platform 350 is inserted into the gap between the adjacent commutator segments 200 to achieve radial positioning of the commutator segment 200 and the PCB board 300.

[0048] The second positioning structure is a positioning platform 360 disposed at the bottom of the PCB board 300. The positioning platform 360 can be integrally formed with the PCB board 300, or can be a structure connected to the PCB board 300; the positioning platform 360 includes a vertically arranged connecting portion 361 and a positioning portion 362, the connecting portion 361 is connected to the inner ring wall surface of the PCB board 300, the positioning portion 362 is bent and extended toward the center of the PCB board 300, and the top surface of the positioning portion 362 is a positioning plane in contact with the commutator segment 200 or the bottom plane of the commutator, such as Figure 8 As shown. A plurality of positioning platforms 360 are provided, and the plurality of positioning platforms 360 are at least three and are evenly distributed. In this embodiment, when installing the commutator segment 200 and the PCB board 300, the commutator segment 200 is moved downward relative to the PCB board 300 until the bottom surface of the commutator segment 200 abuts against the positioning plane, thereby realizing the axial positioning of the commutator segment 200 and the PCB board 300.

[0049] In this embodiment, when the number of commutator segments 200 is six, six gaps are also set between adjacent commutator segments 200. Then, three groups of mounting platforms 350 and positioning platforms 360 can be set respectively, and the mounting platforms 350 and positioning platforms 360 are arranged at intervals. The mounting platforms 350 and positioning platforms 360 cooperate and communicate with each other to realize radial positioning and axial positioning of the commutator segments 200.

[0050] The specific implementation process of this embodiment is as follows:

[0051] In this embodiment, the inductor 400 is electrically connected between two adjacent commutator segments 200, and the filtering principle of the inductor 400 is used to effectively prevent the sudden change of the current when the brush passes through the gap between the commutator segments 200. Figure 4As shown. In this embodiment, when installing and connecting the commutator segment 200 and the PCB board 300, the gap between the connecting portion 361 and the mounting platform 350 and the commutator segment 200 is aligned, and the commutator segment 200 is moved downward until the bottom surface of the commutator segment 200 abuts against the positioning plane to achieve axial positioning of the commutator segment 200 and the PCB board 300. At this time, the three circumferential side surfaces of the mounting platform 350 are respectively in contact with the outer circumferential surface of the commutator segment 200, the side surface of the winding hook foot, and the side surface of the adjacent winding hook foot, so as to achieve radial positioning of the commutator segment 200 and the PCB board 300. In this embodiment, the connection stability between the commutator segment 200 and the PCB board 300 is improved by setting the first positioning structure and the second positioning structure, so that the motor maintains good working stability and dynamic balance during high-speed operation.

[0052] Embodiment 3

[0053] This embodiment is the third embodiment of the DC motor electromagnetic disturbance resistance system of the present invention. This embodiment is similar to the first embodiment or the second embodiment, except that, in this embodiment, the DC motor is connected to the positive electrode and the negative electrode of the power supply through the power connector 500 to form a loop, and the two ends of the power connector 500 are respectively a first connection part 510 and a second connection part 520, the first connection part 510 includes a first plug 511 and a second plug 512 arranged side by side, and the second connection part 520 includes a first terminal 521 and a second terminal 522 arranged side by side, the first terminal 521 is connected to the negative electrode of the power supply through the first plug 511, and the second terminal 522 is connected to the positive electrode of the power supply through the second plug 512, and a filter capacitor 530 is provided between the second plug 512 and the second terminal 522. Fig. 9 , 10 In this embodiment, the filter capacitor 530 can filter out differential mode and common mode noise, thereby ensuring that the power grid is not polluted by the internal noise of the product.

[0054] The second connection portion 520 further includes a third terminal 523 arranged side by side with the first terminal 521 and the second terminal 522, the third terminal 523 is arranged between the second terminal 522 and the first terminal 521, one pin of the filter capacitor 530 is electrically connected to the third terminal 523, and another pin of the filter capacitor 530 is electrically connected to the second terminal 522. In this embodiment, power supply filtering is achieved by adding the third terminal 523, which facilitates the installation and fixation of the filter capacitor 530.

[0055] Specifically, the second connecting portion 520 includes a first wiring cavity 524, a third wiring cavity 526 and a second wiring cavity 525 arranged side by side, and the first terminal 521, the second terminal 522 and the third terminal 523 are respectively located in the first wiring cavity 524, the second wiring cavity 525 and the third wiring cavity 526; the third wiring cavity 526 and the second wiring cavity 525 are separated by a T-shaped support platform 527, and a capacitor placement cavity 528 connected to the third wiring cavity 526 and the second wiring cavity 525 is provided above the T-shaped support platform 527. Specifically, a rectangular opening is opened at the top of the second wiring cavity 525, and a rectangular opening is also opened at the top of the third wiring cavity 526, so as to realize the connection between the capacitor placement cavity 528 and the second wiring cavity 525 and the third wiring cavity 526. The T-shaped support platform 527 is used to support the filter capacitor 530. The capacitor placement cavity 528 provides an installation space for the filter capacitor 530. The capacitor placement cavity 528 is connected to the third wiring cavity 526 and the second wiring cavity 525 to facilitate welding the two pins of the filter capacitor 530 to the second terminal 522 and the third terminal 523, respectively. Fig.10 shown.

[0056] In this embodiment, the first connection portion 510 and the second connection portion 520 are located at two ends of the connector body. The connector body is an integral injection molded part. The capacitor placement cavity 528 is an accommodating space formed by the upward arch of the top surface of the connector body.

[0057] The specific implementation process of this embodiment is as follows:

[0058] The DC motor is connected to the positive pole and the negative pole of the external power supply to form a loop, the first terminal 521 is connected to the negative pole of the power supply through the first plug 511, the second terminal 522 is connected to the positive pole of the power supply through the second plug 512, the third terminal 523 is arranged side by side with the first terminal 521 and the second terminal 522, one pin of the filter capacitor 530 is electrically connected to the third terminal 523, and the other pin of the filter capacitor 530 is electrically connected to the second terminal 522. Fig.11 The filter capacitor 530 of the present invention is installed at the entrance of the power line to ensure that the wire connected to the common end of the noise source is as short as possible, effectively filter out differential mode and common mode noise, and ensure that the power grid is not polluted by the internal noise of the product.

[0059] Embodiment 4

[0060] This embodiment is the fourth embodiment of the DC motor electromagnetic disturbance resistance system of the present invention. This embodiment is similar to the first embodiment or the second embodiment, except that the DC motor further includes an end cap, the carbon brush 100 is installed on the carbon brush holder 600, the carbon brush holder 600 is provided with a first installation slot 611 for installing the first filter capacitor 620 and a second installation slot 612 for installing the second filter capacitor 630, the side wall of the carbon brush holder 600 is provided with a first grounding hole 613 connected to the first installation slot 611 and a second grounding hole 614 connected to the second installation slot 612, one pin of the first filter capacitor 620 is electrically connected to the positive wire 615, and the other pin passes through the first grounding hole 613 to contact and ground the end cap, and one pin of the second filter capacitor 630 is electrically connected to the negative wire 616, and the other pin passes through the second grounding hole 614 to contact and ground the end cap. This embodiment uses the grounding method to isolate and reduce the disturbance, so that it is no longer conducted outward through the power line 617, and effectively solves the problem of electromagnetic disturbance.

[0061] Specifically, in this embodiment, the DC motor is connected to the positive electrode and the negative electrode of the power supply to form a loop; the carbon brush holder 600 includes a housing 610, and one end of the housing 610 is provided with a first interface 618 through which a power line 617 is inserted, and the power line is electrically connected to the power connector 500. The positive wire 615 is connected between the positive electrode of the power supply and the positive fulcrum of the carbon brush 100, and the negative wire 616 is connected between the negative electrode of the power supply and the negative fulcrum of the carbon brush 100. The first mounting groove 611 and the second mounting groove 612 are symmetrically arranged on the left and right sides of the first interface 618. When the positive wire 615 is connected between the positive electrode of the power supply and the positive electrode fulcrum of the carbon brush 100, its winding path passes through the front side of the first mounting groove 611. When the negative wire 616 is connected between the negative electrode of the power supply and the negative electrode fulcrum of the carbon brush 100, its winding path passes through the front side of the second mounting groove 612, which facilitates the electrical connection operation between the first filter capacitor 620 and the positive wire 615, and facilitates the electrical connection operation between the second filter capacitor 630 and the negative wire 616. Fig.12 shown.

[0062] In order to facilitate the other pin of the first filter capacitor 620 to pass through the first grounding hole 613 and stably contact the end cap, and the other pin of the second filter capacitor 630 to pass through the second grounding hole 614 and stably contact the end cap, in this embodiment, a soft plug can be arranged in the first grounding hole 613 and the second grounding hole 614. The pins of the first filter capacitor 620 and the second filter capacitor 630 can not only pass through the soft plug conveniently, but also avoid positional deviation of the pins of the first filter capacitor 620 and the second filter capacitor 630, thereby maintaining stable contact with the end cap.

[0063] The specific implementation process of this embodiment is as follows:

[0064] The DC motor is connected to the positive and negative poles of the external power supply to form a loop. One end of the first filter capacitor 620 is electrically connected to the positive wire 615, and the other end passes through the first grounding hole 613 to contact and ground the end cap. One end of the second filter capacitor 630 is electrically connected to the negative wire 616, and the other end passes through the second grounding hole 614 to contact and ground the end cap. Fig.14 This embodiment uses grounding to isolate and reduce the interference so that it is no longer conducted outward through the power line 617, thereby solving the problem of electromagnetic interference.

[0065] Embodiment 5

[0066] This embodiment is an embodiment of the assembly method of the DC motor electromagnetic disturbance resistance system described in Embodiment 1, comprising the following steps:

[0067] S10 provides a ring-shaped PCB board 300, and a plurality of inductors 400 are welded and fixed along the second circumference on the first side of the PCB board 300, the number of the inductors 400 being equal to the number of the commutator segments 200;

[0068] S20. The commutator segment 200 is fixedly connected to the second side surface of the PCB board 300, and the two terminals of the same inductor 400 are electrically connected to two adjacent commutator segments 200 respectively; the first side surface and the second side surface are two opposite sides of the PCB board 300.

[0069] In this embodiment, the inner ring diameter of the PCB board 300 is smaller than the diameter of the first circle, and the outer ring diameter of the PCB board 300 is larger than the diameter of the first circle. The PCB board 300 is provided with positioning grooves 310, and a plurality of the positioning grooves 310 are arranged around a third circle, and the diameter of the third circle is between the first circle and the second circle.

[0070] In S10 , when the inductor 400 is welded to the PCB board 300 , the two terminals of the inductor 400 are welded to the two opposite groove walls of the positioning groove 310 through the first soldering pad 320 , and the distance between the two opposite groove walls of the positioning groove 310 is substantially equal to the width of the winding portion 210 .

[0071] In S20, the width dimension of the winding portion 210 is smaller than the width dimension of the commutator segment 200, and the width dimension of the mounting hole is slightly larger than the width dimension of the winding portion 210 but smaller than the width dimension of the commutator segment 200. The winding portion 210 of the commutator segment 200 is passed through the mounting hole on the PCB board 300 to the bottom of the commutator segment 200 and abuts against the surface of the PCB board 300. The winding portion 210 is bent along the fold portion until one end of the winding portion 210 is inserted into the positioning groove 310. When the winding portion 210 is inserted into the positioning groove 310, the two side edges of the winding hook foot contact the first solder pad 320 to connect the inductor 400 between two adjacent commutator segments 200.

[0072] In S20, after completing the electrical connection between the winding hook and the commutator segment 200, each commutator segment 200 is welded to the PCB board 300, and the welding points are evenly distributed on the second side of the PCB board 300, which effectively improves the connection stability between the PCB board 300 and the commutator segment 200.

[0073] When this embodiment is implemented, the inductor 400 is electrically connected between two adjacent commutator segments 200, and the filtering principle of the inductor 400 is used to effectively prevent the sudden change of the current when the brush passes through the gap between the commutator segments 200; the connection stability between the PCB board 300 and the commutator segment 200 is improved by multiple connections: the clamping between the winding part 210 and the mounting hole, the clamping between the end of the winding part 210 and the positioning groove 310, and the welding between the commutator segment 200 and the PCB board 300. In addition to the stable connection, the commutator segment 200, the inductor 400, the mounting hole, the positioning groove 310, the solder joint, the PCB board 300, etc. are all centrally symmetrical structures around the axis of the PCB board 300, so as to avoid adverse effects on the dynamic balance of the DC motor running at high speed.

[0074] Embodiment 6

[0075] This embodiment is an embodiment of the assembly method of the DC motor electromagnetic disturbance resistance system described in the second embodiment. This embodiment is similar to the fifth embodiment, except that:

[0076] In S10 , when the inductor 400 is soldered to the PCB board 300 , the connection terminals of adjacent inductors 400 are electrically connected through the third soldering pads 340 .

[0077] In S20, the winding portion 210 is welded to the PCB board 300 through the second pad 330, and the second pad 330 and the third pad 340 can be electrically connected by sinking into the PCB board 300 to a certain depth. For example, the sinking depth of the second pad 330 is a, the sinking depth of the third pad 340 is b, the sum of a and b is greater than the thickness of the PCB board 300, and the projections of the second pad 330 and the third pad 340 in the horizontal plane at least partially overlap, so that the inductor 400 can be connected between two adjacent commutator segments 200 through the contact between the second pad 330 and the third pad 340.

[0078] When installing and connecting the commutator segment 200 and the PCB board 300, the gap between the connecting portion 361 and the mounting platform 350 and the commutator segment 200 is aligned, and the commutator segment 200 is moved downward until the bottom surface of the commutator segment 200 abuts against the positioning plane to achieve axial positioning of the commutator segment 200 and the PCB board 300. At this time, the three circumferential side surfaces of the mounting platform 350 are respectively in contact with the outer circumferential surface of the commutator segment 200, the side surface of the winding hook foot, and the side surface of the adjacent winding hook foot, so as to achieve radial positioning of the commutator segment 200 and the PCB board 300. The connection between the commutator segment 200 and the PCB board 300 is highly stable and will not have an adverse effect on the dynamic balance of the motor during high-speed operation of the motor.

[0079] Embodiment 7

[0080] This embodiment is an embodiment of the assembly method of the DC motor electromagnetic disturbance resistance system described in the third embodiment. Based on the fifth or sixth embodiment, this embodiment further assembles a filter capacitor 530 at the power inlet. The assembly method of the filter capacitor 530 is as follows:

[0081] A power connector 500 is provided, one end of which is a first connection part 510, and the other end is a second connection part 520, the first connection part 510 includes a first plug 511 and a second plug 512 arranged side by side, the second connection part 520 includes a first terminal 521, a second terminal 522 and a third terminal 523 arranged side by side in sequence, the first terminal 521 is connected to the negative electrode wire 616 through the first plug 511, and the second terminal 522 is connected to the positive electrode wire 615 through the second plug 512.

[0082] A filter capacitor 530 is connected between the second terminal 522 and the second plug 512. Specifically, a third terminal 523 is set between the second terminal 522 and the first terminal 521. The filter capacitor 530 is first placed on the T-shaped support platform 527 and placed in the capacitor placement cavity 528. Specifically, the filter capacitor 530 can be snap-fitted with the cavity wall of the capacitor placement cavity 528 by designing the size of the capacitor placement cavity 528 to improve the installation stability of the filter capacitor 530; one pin of the filter capacitor 530 is bent to contact with the third terminal 523 and welded to the third terminal 523, and the other pin of the filter capacitor 530 is bent to contact with the second terminal 522 and welded to the second terminal 522.

[0083] When this embodiment is implemented, the first terminal 521 is connected to the negative wire 616 through the first plug 511, the second terminal 522 is connected to the positive wire 615 through the second plug 512, the third terminal 523 is arranged side by side with the first terminal 521 and the second terminal 522, one pin of the filter capacitor 530 is electrically connected to the third terminal 523, and the other pin of the filter capacitor 530 is electrically connected to the second terminal 522. In this embodiment, the filter capacitor 530 is installed at the entrance of the power line 617 to ensure that the wire connected to the common end of the noise source is as short as possible, effectively filter out differential mode and common mode noise, and ensure that the power grid is not polluted by the internal noise of the product.

[0084] Embodiment 8

[0085] This embodiment is an embodiment of the assembly method of the DC motor electromagnetic disturbance resistance system described in the fourth embodiment. Based on the fifth or sixth embodiment, this embodiment adds a grounded filter capacitor 530 on the carbon brush holder 600. The assembly method of the first filter capacitor 620 and the second filter capacitor 630 is as follows:

[0086] A carbon brush holder 600 and an end cover are provided, wherein a first mounting groove 611 for mounting a first filter capacitor 620 and a second mounting groove 612 for mounting a second filter capacitor 630 are provided in the carbon brush holder 600; the width of the first mounting groove 611 is equal to or slightly smaller than the width of the first filter capacitor 620, so that the first filter capacitor 620 can be inserted into the first mounting groove 611; the width of the second mounting groove 612 is equal to or slightly smaller than the width of the second filter capacitor 630, so that the second filter capacitor 630 can be inserted into the second mounting groove 612; the first filter capacitor 620 and the second filter capacitor 630 can be stably installed without other fixing methods;

[0087] One pin of the first filter capacitor 620 is welded to the positive wire 615 to achieve electrical connection, and the other pin passes through the first grounding hole 613 to contact and ground the end cover. One pin of the second filter capacitor 630 is welded to the negative wire 616 to achieve electrical connection, and the other pin passes through the second grounding hole 614 to contact and ground the end cover.

[0088] When this embodiment is implemented, the first filter capacitor 620 is inserted into the first installation groove 611, and the second filter capacitor 630 is inserted into the second installation groove 612. One pin of the first filter capacitor 620 is electrically connected to the positive wire 615, and the other pin passes through the soft plug in the first grounding hole 613 to stably contact the end cover. One pin of the second filter capacitor 630 is electrically connected to the negative wire 616, and the other pin passes through the soft plug in the second grounding hole 614 to stably contact the end cover. By using the grounding method, the interference is isolated and reduced so that it is no longer conducted outward through the power line 617, so as to solve the problem of electromagnetic interference.

[0089] In the specific contents of the above-mentioned specific implementation methods, the various technical features can be combined in any non-contradictory manner. In order to make the description concise, not all possible combinations of the above-mentioned technical features are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0090] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the embodiments here. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. A DC motor electromagnetic disturbance resistance system, the DC motor comprising a carbon brush (100) and a plurality of commutator segments (200) that rotate and contact with the carbon brush (100) to achieve commutation, the plurality of commutator segments (200) being arranged around a first circumference; characterized in that: The electromagnetic disturbance resistance system comprises a PCB (300) and an inductor (400) having an equal number to the number of commutator segments (200); a plurality of the inductors (400) are fixedly mounted on the PCB (300) along a second circumference and two terminals of the same inductor (400) are respectively electrically connected to two adjacent commutator segments (200); the commutator segments (200) are fixedly connected to the PCB (300); and the commutator segments (200) and the inductors (400) are respectively mounted on two opposite sides of the PCB (300); The DC motor is connected to the positive electrode and the negative electrode of the power supply through a power connector (500) to form a loop. The two ends of the power connector (500) are respectively a first connection part (510) and a second connection part (520). The first connection part (510) comprises a first plug (511) and a second plug (512) arranged side by side. The second connection part (520) comprises a first terminal (521) and a second terminal (522) arranged side by side. The first terminal (521) is connected to the negative electrode of the power supply through the first plug (511). The second terminal (522) is connected to the positive electrode of the power supply through the second plug (512). A filter capacitor (530) is provided between the second plug (512) and the second terminal (522). The second connection portion (520) further comprises a third terminal (523) arranged side by side with the first terminal (521) and the second terminal (522), wherein the third terminal (523) is arranged between the second terminal (522) and the first terminal (521), one pin of the filter capacitor (530) is electrically connected to the third terminal (523), and another pin of the filter capacitor (530) is electrically connected to the second terminal (522); The second connecting portion (520) includes a first wiring cavity (524), a third wiring cavity (526) and a second wiring cavity (525) arranged side by side, and the first wiring post (521), the second wiring post (522) and the third wiring post (523) are respectively located in the first wiring cavity (524), the second wiring cavity (525) and the third wiring cavity (526); the third wiring cavity (526) and the second wiring cavity (525) are separated by a T-shaped support platform (527), and a capacitor placement cavity (528) connected to the third wiring cavity (526) and the second wiring cavity (525) is provided above the T-shaped support platform (527).

2. The DC motor electromagnetic disturbance resistance system according to claim 1 is characterized in that: A winding portion (210) is provided at the bottom of the commutator segment (200), and a mounting hole is provided on the PCB board (300) for allowing the winding portion (210) to pass through. After passing through the mounting hole, the winding portion (210) is bent toward a side close to the inductor (400) to form a winding hook angle; the second circumference is arranged concentrically with the first circumference and the diameter of the second circumference is greater than the diameter of the first circumference, and two wiring terminals of the inductor (400) are respectively electrically connected to two adjacent winding hook angles.

3. The DC motor electromagnetic disturbance resistance system according to claim 2 is characterized in that: The PCB board (300) is provided with a positioning groove (310), one end of the winding portion (210) passing through the mounting hole is clamped in the positioning groove (310), and a plurality of the positioning grooves (310) are arranged around a third circumference, the third circumference is arranged concentrically with the second circumference and the first circumference, and the diameter of the third circumference is between the diameter of the first circumference and the diameter of the second circumference; the two opposite groove walls of the positioning groove (310) are trapezoidal in shape, the cross-sectional dimensions of which gradually increase from top to bottom; the two opposite groove walls of the positioning groove (310) are provided with a first soldering pad (320) electrically connected to the inductor (400), and the first soldering pad (320) is inscribed in the trapezoid.

4. The DC motor electromagnetic disturbance resistance system according to claim 1, characterized in that: The PCB board (300) is a circular ring structure; a winding portion (210) is provided at the bottom of the commutator segment (200); the winding portion (210) is provided between the commutator segment (200) and the inner ring surface of the circular ring structure; the winding portion (210) is connected to the PCB board (300) via a second soldering pad (330); the connection terminals of two adjacent inductors (400) are electrically connected via a third soldering pad (340); and the second soldering pad (330) is electrically connected to the third soldering pad (340).

5. The DC motor electromagnetic disturbance resistance system according to claim 4, characterized in that: A first positioning structure for radial positioning and a second positioning structure for axial positioning are provided between the PCB board (300) and the commutator segment (200); the first positioning structure and the second positioning structure are both provided on the PCB board (300).

6. The DC motor electromagnetic disturbance resistance system according to any one of claims 1 to 5, characterized in that: The DC motor further comprises an end cover, the carbon brush (100) is mounted on a carbon brush holder (600), a first mounting groove (611) for mounting a first filter capacitor (620) and a second mounting groove (612) for mounting a second filter capacitor (630) are provided in the carbon brush holder (600), a first grounding hole (613) connected to the first mounting groove (611) and a second grounding hole (614) connected to the second mounting groove (612) are provided on a side wall of the carbon brush holder (600), one pin of the first filter capacitor (620) is electrically connected to a positive lead (615), and the other pin passes through the first grounding hole (613) to contact and be grounded to the end cover, and one pin of the second filter capacitor (630) is electrically connected to a negative lead (616), and the other pin passes through the second grounding hole (614) to contact and be grounded to the end cover.

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