Motor

Abstract

The utility model relates to a motor, which comprises a shell, a stator assembly and a rotor assembly, the stator assembly and the rotor assembly are positioned in the shell, the stator assembly comprises a stator and a stator winding, the stator winding is electrically connected with a printed circuit board assembly at an axial end, and the printed circuit board assembly is electrically connected with a motor plug positioned on the outer side of the shell. The first printed circuit board and the second printed circuit board are arranged at an axial interval and are electrically connected with each other, and each of the first printed circuit board and the second printed circuit board comprises a protruding part which extends into the receiving cavity of the motor plug. According to the motor provided by the utility model, the two printed circuit boards which are spaced in the axial direction are utilized, and each printed circuit board is provided with the protruding part which extends into the motor plug, so that even under the conditions that the outer diameter size of the motor is relatively small, the power of the motor is relatively large, and the working current of the motor is relatively large, the motor cannot be damaged. Spatial arrangement requirements of various electronic devices can be met, and wiring can conform to automobile industry specifications.

Description

Technical Field

[0001] The utility model relates to the technical field of motors, in particular to a motor comprising an improved printed circuit board assembly. Background Art

[0002] With the development of science and technology, in order to meet the needs of automobile users as much as possible and improve the user's comfort, more and more functions are integrated into the automobile. In order to realize these functions, motors, especially brushless motors, are widely used in the automotive field.

[0003] A brushless motor generally includes a stator assembly and a rotor assembly, wherein the stator assembly includes a stator and a stator winding wound on the stator, and the stator winding can realize the torque output and signal transmission of the motor by being electrically connected to a printed circuit board assembly (PCBA). In most existing brushless motor designs, three-phase winding control is mostly required. When a high-power circuit is built-in for driving, not only six relatively large Mosfet transistors are required, but also a relatively large main control chip and external supporting circuits need to be placed on the printed circuit board (PCB). Considering the space required for both, the printed circuit board is required to provide at least an approximately 16mm×16mm layout space. However, when such a design requirement occurs when the motor size is relatively small (for example, a motor with an outer diameter of less than 40mm), the motor power is relatively large, and the motor operating current is relatively large, especially when the PCB wiring is required to comply with automotive industry specifications and the rotor shaft needs to pass through the middle of the PCB board, it is difficult to achieve these functions with a small-sized motor structure design with a single-layer PCB.

[0004] In particular, in order to meet the automotive industry specifications and make the EMC test of brushless motors used in automobiles meet the CISPR25 Class 5 level requirements, it is usually necessary to place one or more relatively large filter capacitors in the PCBA to meet the filtering and EDS requirements, thus placing greater demands on the wiring space that the PCBA can provide.

[0005] Therefore, it is necessary to propose a new motor structure that can integrate the main control chip and inverter circuit into the motor body even when limited by the small size of the motor, while also allowing the installation of large-capacity filter capacitors and filter circuit designs to achieve the required filtering function. Utility Model Content

[0006] The utility model is proposed based on such background. Specifically, the utility model proposes a motor, which includes a housing and a stator assembly and a rotor assembly located in the housing, the stator assembly includes a stator and a stator winding wound on the stator, the stator winding is electrically connected to a printed circuit board assembly at one axial end, the printed circuit board assembly is electrically connected to a motor plug located outside the housing, and includes a first printed circuit board and a second printed circuit board that are electrically connected to each other and arranged at intervals in the axial direction, the first printed circuit board and the second printed circuit board each including a protruding portion extending into a receiving cavity of the motor plug.

[0007] According to an embodiment of the present invention, the first printed circuit board and the second printed circuit board each further include a main body portion connected to the protruding portion and located inside the housing, and the main body portion is provided with a central through hole for the rotor shaft of the rotor assembly to pass through.

[0008] According to an implementation manner of the utility model, the first printed circuit board carries a filter circuit; and the second printed circuit board carries a main control circuit and an inverter circuit of the motor.

[0009] According to one embodiment of the utility model, the motor plug includes a plug body defining the receiving cavity, and three slots are arranged in the receiving cavity, wherein one end of each of the positive pin, the negative pin and the signal pin is respectively press-fitted (for example, interference fit is achieved through an extrusion process) in a corresponding slot among the three slots.

[0010] According to one embodiment of the utility model, the other ends of the positive electrode pin and the negative electrode pin extending from the corresponding slots are respectively inserted through the corresponding receiving holes of the first printed circuit board and fixedly connected to the first printed circuit board; the other ends of the signal pin extending from the corresponding slots are sequentially inserted through the corresponding receiving holes in the first printed circuit board and the second printed circuit board and fixedly connected to the first printed circuit board and the second printed circuit board.

[0011] According to one embodiment of the utility model, a first pin and a second pin for conducting current filtered by a filter circuit are also fixed on the first printed circuit board, and the first pin and the second pin are respectively inserted through corresponding receiving holes of the second printed circuit board at one end extending from the first printed circuit board and are fixedly connected to the second printed circuit board.

[0012] According to one embodiment of the utility model, a fixing pin for providing a positioning and fixing function is also fixed on the first printed circuit board, and one end of the fixing pin extending from the first printed circuit board is inserted through the corresponding receiving hole of the second printed circuit board and fixedly connected to the second printed circuit board.

[0013] According to one embodiment of the present invention, the fixing points of the first pin, the second pin, the fixed pin and the signal pin on each printed circuit board are approximately triangular, so that the second printed circuit board can stably maintain a spaced relationship with respect to the first printed circuit board.

[0014] According to one embodiment of the utility model, the motor plug also includes a plug cover, which is snap-fitted with the plug body through a snap-fit ​​structure to encapsulate the protruding parts of the first printed circuit board and the second printed circuit board in the receiving cavity; the main parts of the first printed circuit board and the second printed circuit board are encapsulated in the shell through the end cover of the motor.

[0015] According to an embodiment of the utility model, a through hole is provided on the first printed circuit, a fixed portion of the grounding spring is received in the through hole, and a flexible portion of the grounding spring located outside the through hole abuts against the housing to achieve grounding.

[0016] Compared with the prior art, especially in the design of small-sized motors, the technical solution according to the utility model can achieve at least one of the following technical effects: through two PCB boards, the main control chip and the inverter circuit can be integrated into the motor housing, and at the same time, by extending the two PCB boards out of the motor housing and entering the receiving cavity of the motor plug, the space of the motor plug can be fully utilized, which can not only realize high-current drive, large-size main control unit selection, and reasonable automotive-grade PCB wiring, but also allow the placement of large-capacity filter capacitors and filter circuit designs that can adapt to high power. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The above and other features and advantages of the present invention will become more easily understood through the following description with reference to the accompanying drawings, in which:

[0018] Figure 1 A schematic diagram of the structure of a motor according to the utility model is shown;

[0019] Figure 2a and Figure 2b The installation is shown in a perspective view and a side view respectively. Figure 1 The structure of the printed circuit board assembly in the motor shown;

[0020] Figure 3a and Figure 3b The components are shown respectively Figure 2a and Figure 2b A schematic structural diagram of a first printed circuit board and a second printed circuit board of a printed circuit board assembly;

[0021] Figure 4a Shows Figure 2a and Figure 2bA three-dimensional schematic diagram of a printed circuit board assembly and a motor plug when assembled together;

[0022] Figure 4b Shows Figure 2a and Figure 2b A partially exploded schematic diagram showing the printed circuit board assembly and the motor plug when assembled with each other; and

[0023] Figure 5 A three-dimensional schematic diagram of a plug body of a motor plug is shown, wherein a positive electrode pin, a negative electrode pin and a signal pin are fixedly arranged in a receiving cavity of the plug body.

[0024] All the drawings are only schematic and not necessarily drawn to scale, and they only show those parts necessary for illustrating the present invention, and other parts are omitted or merely mentioned. That is, in addition to the parts shown in the drawings, the present invention may also include other parts. DETAILED DESCRIPTION

[0025] In the following description, many specific details are set forth so that those skilled in the art can more fully understand the present invention. However, it is obvious to those skilled in the art that the present invention may be implemented without some of these specific details. The following various aspects, features, embodiments and advantages are for illustrative purposes only and should not be regarded as elements or limitations of the claims unless explicitly stated in the claims. Terms such as "first" and "second" are used below to describe the elements of the present application, and these terms are only used to distinguish between the various elements without intending to limit the nature, sequence, order or number of these elements. In addition, it should be noted that in this specification, the same and / or functionally identical technical features are marked with the same or similar figures.

[0026] As mentioned in the background technology, in the existing motor design, only a single printed circuit board located in the motor housing is usually provided at an axial end of the stator winding, which usually has a shape (such as a circle) that matches the cylindrical shape of the motor housing. However, in small-sized motors (such as motors with an outer diameter of less than 40 mm), when the motor power and the operating current are relatively large, the copper on the printed circuit board is usually wider, and a larger safety distance needs to be maintained between the electronic components, which undoubtedly increases the difficulty of routing and arranging components in small-sized motors. In addition, in order to simultaneously integrate the main control chip and the inverter circuit into the interior of the housing, while also allowing the placement of large-capacity filter capacitors and filter circuit designs that adapt to high power (for example, to meet the requirements of the automotive industry specifications for EMC), the single printed circuit board design in the prior art is obviously unable to meet the layout requirements of electronic components.

[0027] To this end, the utility model proposes an improved solution, which solves the problems of limited space for electronic component layout and difficult wiring through the structural design of a high-power drive PCBA built into a miniature small-sized motor.

[0028] In the motor structure design of the utility model, it is proposed to use two PCB boards arranged at a distance from each other in the axial direction of the motor to jointly complete the functions of driving the motor and filtering. At the same time, by extending the two PCB boards out of the motor housing and entering the receiving cavity of the motor plug to fully utilize the space of the motor plug, the routing and layout of electronic components in a small space are completed.

[0029] Specifically, Figure 1 The schematic diagram of the structure of the motor according to the utility model is shown. The utility model mainly relates to small-sized motors (especially brushless motors), for example, the motor outer diameter A is less than 40mm, such as 20-38mm, and the motor axial length B is 40-100mm. Of course, this is not intended to limit the application of the utility model in motors of other sizes.

[0030] The motor 1 includes a housing 10, a stator assembly and a rotor assembly located in the housing 10, and a motor plug 20 located outside the housing 10 and intended to be connected to a client plug and then to a power source. The stator assembly includes a stator and a stator winding wound on the stator, and the stator winding is connected to a printed circuit board assembly (PCBA) at one axial end. Figure 1 The printed circuit board assembly is electrically connected to the motor plug 20 (not shown).

[0031] Figure 2a and Figure 2b The installation is shown in a perspective view and a side view respectively. Figure 1 The structure of the improved printed circuit board assembly 30 in the motor is shown.

[0032] Different from the single PCB design in the prior art, the printed circuit board assembly 30 in the present invention includes two printed circuit boards 31 and 32 that are arranged in an axial direction and electrically connected to each other, one of which can be designed for the main control circuit and inverter circuit of the motor, and the other printed circuit board can be designed for the filter circuit design with respect to the CISPR25Class5 level requirements. The distance F between the two printed circuit boards (see Figure 2b ) is preferably 3-10 mm. Of course, this distance value can be adaptively selected and adjusted according to the actual needs of the motor design.

[0033] Continue to see Figure 3a and Figure 3b , which respectively show the composition Figure 2a and Figure 2bA schematic structural diagram of two printed circuit boards of the printed circuit board assembly 30 in FIG. Figure 3a The first printed circuit board 31 carrying the filter circuit is shown. Figure 2a As shown in FIG. 3 , the filter circuit is provided with three large-capacity filter capacitors 311. Of course, filter capacitors of other numbers and sizes may also be selected according to the power size. Figure 3b The second printed circuit board 32 is shown as carrying the main control circuit and the inverter circuit of the motor. For example, the main control chip and six Mosfet transistors are carried on the surface of the second printed circuit board 32 facing the first printed circuit board 31, and three Hall sensors 321 are carried on the other surface opposite to the first printed circuit board 31. Figure 4b ), these Hall sensors 321 can be used to detect the rotational position accuracy of the rotor shaft, etc.

[0034] Depend on Figure 3a and Figure 3b It can be seen that the first and second printed circuit boards have substantially the same appearance. Each printed circuit board includes a main body 31a, 32a and a protruding portion 31b, 32b extending from the main body, wherein the main body is located in the housing 10 of the motor, and the protruding portion extends out of the housing of the motor and is received in the receiving cavity of the motor plug 20, so that the space of the motor plug 20 can be fully utilized, thereby freeing up more space for the main body for the setting of a large-sized main control unit and a filter circuit, while also meeting the corresponding wiring requirements of the vehicle standard level.

[0035] like Figure 3a and Figure 3b As shown, in order to adapt to the cylindrical shape of the motor housing, the main body part preferably adopts a roughly circular shape, and its outer diameter C is preferably between 18-36 mm. For example, when the outer diameter of the motor is 36 mm, the outer diameter C of the printed circuit board is about 33.8 mm. In addition, the main body part is provided with a central through hole for the rotor shaft of the rotor assembly to pass through, and the inner diameter C1 of the central through hole is within 12 mm. In addition, the protruding part connected to the main board part is designed to be roughly rectangular in shape, and its width D is 10-28 mm. In particular, when the width D is 17 mm, it can basically meet the design requirements of the main control unit with a large size of 7 mm×7 mm and the size and space requirements of the external circuit. In addition, the height E of the outermost edge of the protruding part from the center of the central through hole can be selected to be 16-30 mm. Of course, all of the above dimensions can be adjusted and selected according to the actual motor structure.

[0036] Figure 4a and Figure 4b They are shown respectively Figure 2a and Figure 2bThe PCB assembly 30 and the motor plug 20 are shown as a three-dimensional schematic diagram of being assembled together. The motor plug 20 is located outside the housing 10. See in particular Figure 4b The motor plug 20 includes a plug body 21 defining a receiving cavity 211. It can be seen that the protruding portions of the two printed circuit boards are inserted into the receiving cavity 211 of the motor plug 20. The motor plug 20 also includes a plug cover 22, which is snap-fitted with the plug body 21 through a snap-fit ​​structure (see FIG. Figure 4a ), so as to encapsulate the protruding parts of the first printed circuit board 31 and the second printed circuit board 32 in the receiving cavity 211. In addition, the main parts of the first printed circuit board 31 and the second printed circuit board 32 are encapsulated in the housing 10 of the motor through the end cover of the motor.

[0037] See especially Figure 5 , which shows a three-dimensional schematic diagram of the plug body 21 of the motor plug 20. A positive pin 212, a negative pin 213, and a Lin or Can signal pin 214 are fixedly arranged in the receiving cavity 211 of the plug body 21. These pins can be formed into a single part with the motor plug 20 through a rubber coating process, and then connected to two printed circuit boards by soldering; or these pins can be press-fitted with the slots reserved on the motor plug, and then connected to two printed circuit boards by soldering to form a whole.

[0038] Specifically, in the process of assembling the electrode plug 20 and the printed circuit board assembly 30, one end of the positive pin 212 and the negative pin 213 (this end is intended to cooperate with the client plug) can be first press-fitted into the corresponding slot of the electrode plug 20, and the other end extending from the corresponding slot is inserted through the corresponding receiving hole of the first printed circuit board 31 carrying the filter circuit and fixedly connected to the first printed circuit board 31, such as soldering. One end of the Lin or Can signal pin 214 (this end is intended to cooperate with the client plug) is press-fitted into the corresponding slot of the electrode plug 20, and the other end extending from the corresponding slot is inserted through the corresponding receiving holes in the first printed circuit board 31 and the second printed circuit board 32 carrying the main control circuit, etc., and fixedly connected to the first printed circuit board 31 and the second printed circuit board 32, such as soldering. Finally, a structure such as the following is formed. Figure 4a and Figure 4b Components shown.

[0039] See also Figure 2a and Figure 4b, a first pin 312 and a second pin 313 for conducting the current filtered by the filter circuit are also fixed on the first printed circuit board 31. One end of the first pin 312 and the second pin 313 extending from the first printed circuit board 31 are respectively inserted through the corresponding receiving holes of the second printed circuit board 32 and are fixedly connected to the second printed circuit board 32. In addition, a fixing pin 314 for providing a positioning and fixing function is also fixed on the first printed circuit board 31. One end of the fixing pin 314 extending from the first printed circuit board 31 is inserted through the corresponding receiving holes of the second printed circuit board 32 and is fixedly connected to the second printed circuit board 32.

[0040] It should be known that the fixed connection mentioned above can be carried out in a suitable manner known in the prior art, such as soldering connection. Of course, other possible connection methods besides soldering connection can also be used, such as press-fitting of pins with metallized receiving holes.

[0041] In order to more conveniently illustrate the relative positional relationship between each plug fixed on the first printed circuit board 31 and each plug fixed in the motor plug 20, Figure 2a The positive electrode plug 212, the negative electrode plug 213 and the signal plug 214 fixed in the receiving cavity 211 of the motor plug 20 are specifically shown. Figure 2a As shown, the first pin 312 and the second pin 313, the fixed pin 314 and the signal pin 214 are each fixed at a point on each printed circuit board that is approximately a triangle (wherein the first and second pins can be regarded as a vertex of the triangle because they are arranged adjacent to each other), so that the second printed circuit board 32 can stably maintain a spaced relationship with respect to the first printed circuit board 31.

[0042] In addition, a through hole is provided on the first printed circuit 31 , in which a fixed portion of the grounding spring 315 is received, and a flexible portion of the grounding spring 315 outside the through hole abuts against the housing 10 of the motor to achieve effective grounding.

[0043] When the PCB assembly discussed above is installed in the housing of the motor, the PCB assembly can be electrically connected to the stator winding, such as the three-phase winding, through the connection structure, for example, the coil of each phase winding is electrically connected to the PCB assembly to achieve torque output and signal transmission. Specifically, as an example, in the case of Figure 3bAs shown, the second printed circuit board 32 carrying the main control circuit is provided with three through holes 322 spaced 60 degrees apart from each other in the circumferential direction. The three through holes 322 may be in the form of tin-plated holes, which are intended to be press-fitted with three contact sections of the corresponding three-phase windings on the connection structure, such as in the form of fisheye pins, to achieve electrical connection. In addition, another separate tin-plated through hole 323 is also provided on the second printed circuit board 32, which is intended to be press-fitted with a common end contact section, such as in the form of fisheye pins. When realizing the press-fit connection between the contact sections of the connection structure of the printed circuit board assembly and the stator winding, four radial notches 316 are preferably provided on the first printed circuit board 31, so that the pressing tool can pass through the radial notches and abut against the second printed circuit board 32, so that it is pressed against the contact section to be connected thereto, and finally the electrical connection between the printed circuit board assembly and the stator winding is completed.

[0044] By adopting the motor according to the utility model, two printed circuit boards are used and each printed circuit board has a protruding portion extending into the motor plug. Even when the outer diameter of the motor is relatively small, the motor power is relatively large, and the motor operating current is relatively large, the space layout requirements of various electronic devices can be met, and the wiring can also comply with the automotive industry specifications.

[0045] For those skilled in the art, various modifications and variations may be made to the embodiments disclosed above without departing from the scope or spirit of the utility model. Other embodiments of the utility model will be apparent to those skilled in the art from the practice of the utility model disclosed in this specification. This specification and the examples disclosed therein should be considered to be illustrative only, and the true scope of the utility model is specified by the appended claims and their equivalents.

Claims

1. A motor comprising a housing and a stator assembly and a rotor assembly located in the housing, wherein the stator assembly comprises a stator and a stator winding wound on the stator, wherein the stator winding is electrically connected to a printed circuit board assembly at one axial end, wherein: The printed circuit board assembly is electrically connected to the motor plug located outside the housing, and includes a first printed circuit board and a second printed circuit board that are electrically connected to each other and arranged at a distance in the axial direction, wherein the first printed circuit board and the second printed circuit board each include a protruding portion that extends into a receiving cavity of the motor plug.

2. The motor according to claim 1, characterized in that The first printed circuit board and the second printed circuit board each further include a main body portion connected to the protruding portion and located in the housing, wherein the main body portion is provided with a central through hole for a rotor shaft of a rotor assembly to pass through.

3. The motor according to claim 2, characterized in that The first printed circuit board carries a filter circuit; the second printed circuit board carries a main control circuit and an inverter circuit of the motor.

4. The motor according to claim 3, characterized in that The motor plug includes a plug body defining the receiving cavity, wherein three slots are arranged in the receiving cavity, wherein one end of each of the positive pin, the negative pin and the signal pin is press-fitted into a corresponding slot among the three slots.

5. The motor according to claim 4, characterized in that The other ends of the positive and negative pins extending from the corresponding slots are respectively inserted through the corresponding receiving holes of the first printed circuit board and fixedly connected to the first printed circuit board; the other ends of the signal pins extending from the corresponding slots are sequentially inserted through the corresponding receiving holes in the first and second printed circuit boards and fixedly connected to the first and second printed circuit boards.

6. The motor according to claim 5, characterized in that The first printed circuit board is also fixed with a first pin and a second pin for conducting current filtered by the filter circuit. The first pin and the second pin are respectively inserted through corresponding receiving holes of the second printed circuit board at one end extending from the first printed circuit board and are fixedly connected to the second printed circuit board.

7. The motor according to claim 6, characterized in that A fixing pin for providing a positioning and fixing function is also fixed on the first printed circuit board. One end of the fixing pin extending from the first printed circuit board is inserted through a corresponding receiving hole of the second printed circuit board and fixedly connected to the second printed circuit board.

8. The motor according to claim 7, characterized in that The fixing points of the first pin, the second pin, the fixed pin and the signal pin on each printed circuit board are approximately triangular, so that the second printed circuit board can stably maintain a spaced relationship with respect to the first printed circuit board.

9. The electric machine according to any one of claims 4 to 8, characterized in that The motor plug further comprises a plug cover, wherein the plug cover is snap-engaged with the plug body through a snap-fit ​​structure to encapsulate the protruding parts of the first printed circuit board and the second printed circuit board in the receiving cavity; The main parts of the first printed circuit board and the second printed circuit board are enclosed in the housing through the end cover of the motor.

10. The electric machine according to any one of claims 1 to 8, characterized in that A through hole is provided on the first printed circuit, in which a fixed part of a grounding spring is received, and a flexible part of the grounding spring located outside the through hole abuts against the housing to achieve grounding.

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