WO2021258417A1

WO2021258417A1 - Micro loudspeaker

Info

Publication number: WO2021258417A1
Application number: PCT/CN2020/099853
Authority: WO
Inventors: 肖波; 令狐荣林; 孔晨亮; 章统
Original assignee: 瑞声声学科技(深圳)有限公司; 瑞声科技(新加坡)有限公司
Priority date: 2020-06-24
Filing date: 2020-07-02
Publication date: 2021-12-30
Also published as: CN111836175B; CN111836175A

Abstract

The present application provides a micro loudspeaker, comprising a housing, a vibration system, and a magnetic circuit system. A support plate is provided in the housing; a first through hole is formed in the support plate; the vibration system comprises a voice coil, a first vibrating diaphragm, a diaphragm, and a second vibrating diaphragm which are sequentially arranged at intervals along the short axis direction of the voice coil, a first hollow connecting member clamped between the first vibrating diaphragm and the diaphragm, and a second hollow connecting member clamped between the diaphragm and the second vibrating diaphragm; the first vibrating diaphragm and the second vibrating diaphragm are both fixedly held on the housing; the diaphragm is fixedly held on the support plate and covers the first through hole; the first vibrating diaphragm is connected to the voice coil; the first vibrating diaphragm, the housing, the support plate, and the diaphragm enclose a first vibrating diaphragm front cavity; a second through hole is formed in the diaphragm; a third through hole is formed in the second vibrating diaphragm; the first vibrating diaphragm front cavity is communicated with the outside through the hollow structure of the first connecting member, the second through hole, the hollow structure of the second connecting member, and the third through hole in sequence. The micro loudspeaker provided by the present application can achieve strong bass performance.

Description

Micro speakers

Technical field

This application relates to the field of electro-acoustic conversion, in particular to a miniature loudspeaker.

Background technique

In the existing side-sounding micro-speakers, the vibration system generally only includes a diaphragm arranged on the side of the micro-speaker. This arrangement makes the effective radiation area of the micro-speaker limited, resulting in limited bass performance under the same amplitude. That is to say, in the case of the same bass output, this setting method requires the micro speaker to have a higher amplitude, which is not conducive to prolonging the life of the micro speaker, but also makes the volume requirement of the back cavity of the mobile phone higher.

Therefore, it is necessary to provide a micro speaker with a new structure to solve the above technical problems.

technical problem

The purpose of this application is to provide a miniature loudspeaker in which an airflow enhancement system composed of a multi-sound film is arranged to solve the limitation of the effective radiation area of the existing side-sounding miniature loudspeaker, which leads to the low frequency provided under the same amplitude. Issues with limited performance.

Technical solutions

The technical solution of the present application is as follows: a micro speaker is provided, which includes a housing with a housing space, a vibration system, and a magnetic circuit system housed in the housing space, the housing includes a first side wall, A second side wall extending from the edge of the first side wall and a supporting plate extending from the second side wall into the containing space, and a first through hole is provided on the supporting plate;

The vibration system includes a voice coil, a first diaphragm, a diaphragm, and a second diaphragm arranged at intervals along the short axis of the voice coil, and a hollow sandwiched between the first diaphragm and the diaphragm. The first connecting member and the hollow second connecting member sandwiched between the diaphragm and the second diaphragm; the first plane formed by the long axis side and the short axis side of the voice coil is connected to the The plane where the first diaphragm is located, the plane where the diaphragm is located, and the plane where the second diaphragm is located are perpendicular to each other;

The first diaphragm and the second diaphragm are both fixed on the second side wall, the diaphragm is fixed on the support plate and covered by the first through hole, and the first vibration The membrane is connected to the voice coil;

The first diaphragm and the second side wall, the support plate, and the diaphragm are enclosed to form a first diaphragm front cavity, the diaphragm is provided with a second through hole, and the second diaphragm is A third through hole is provided, and the first diaphragm front cavity sequentially passes through the hollow structure of the first connecting piece, the second through hole, the hollow structure of the second connecting piece, and the third through hole. The hole communicates with the outside world;

The second diaphragm and the second side wall, the supporting plate, the diaphragm, and the outer peripheral wall of the second connecting member are surrounded to form a closed second diaphragm rear cavity;

The magnetic circuit system includes a first magnet assembly and a second magnet assembly arranged at intervals along a direction perpendicular to the first plane, and the voice coil is arranged between the first magnet assembly and the second magnet assembly.

Preferably, the first connecting member includes a hollow supporting column, a first fixing portion bent and extending from the edge of the supporting column, and two oppositely spaced ends of the supporting column away from the first fixing portion. A second fixing portion, the second fixing portion includes a support arm extending from the edge of the support column and a support platform bent and extended from the end of the support arm away from the support column; the first fixing portion clip It is arranged between the support column and the inner peripheral side of the diaphragm, and the support platform is sandwiched between the support arm and the inner peripheral side of the first diaphragm.

Preferably, the outer peripheral side of the diaphragm is covered by the first through hole, and the inner peripheral side of the diaphragm is sandwiched between the first connecting piece and the second connecting piece; the second connecting piece The hole is provided on the inner peripheral side of the diaphragm, and the diaphragm further includes a first folding ring portion protruding in the direction of the second diaphragm.

Preferably, the housing further includes a first joint ring bent and extended from the edge of the support plate, and a third fixing part bent and extended from the end of the first joint ring away from the support plate, the The first joining ring is fixedly arranged on the second side wall, and the third fixing part is sandwiched between the second diaphragm and the second side wall.

Preferably, the housing further includes a second joint ring fixedly arranged on the second side wall for holding the first diaphragm.

Preferably, the vibration system further includes a skeleton component coupled to one side of the first diaphragm for connecting the voice coil and the first diaphragm, and the skeleton component includes two skeletal components along the length of the voice coil. A skeleton arranged at relatively intervals in the axial direction, the skeleton including a first joint portion and a second joint portion arranged at intervals along the long-axis side of the voice coil for clamping the short-axis side of the voice coil, and a connection The first main body part of the first joint part and the second joint part, and the first main body part is connected to the first diaphragm.

Preferably, the first diaphragm includes a first sound film, and a first dome sandwiched between the first sound film and the first connecting member; the first dome is attached to the On the inner peripheral side of the first sound membrane, the first sound membrane includes a second folding ring portion protruding in a direction toward the second diaphragm.

Preferably, the second diaphragm includes a second sound diaphragm and a second dome attached to the inner peripheral side of the second sound diaphragm away from the second side wall; the second sound diaphragm includes A third folding ring portion protruding in a direction away from the second side wall.

Preferably, the vibration system further includes a flexible circuit board assembly fixedly arranged on the first side wall, and the flexible circuit board assembly includes two flexible circuit boards arranged at opposite intervals along the long axis of the voice coil. , The flexible circuit board is electrically connected to the voice coil.

Preferably, the magnetic circuit system further comprises a first clamping plate and a second clamping plate arranged at intervals along the short axis of the voice coil, and the first magnet assembly and the second magnet assembly are arranged on the first clamping plate And the second splint, the first splint is fixedly arranged on the first side wall, and the second joint ring is sandwiched between the second splint and the first diaphragm.

Preferably, the first side wall is provided with a first assembly opening and a second assembly opening symmetrically arranged on both sides of the first assembly opening, and the first clamping plate is embedded in the first assembly opening, so Part of the structure of the flexible circuit board is respectively embedded in the corresponding second assembly opening.

Beneficial effect

The beneficial effect of the present application is that the micro speaker of the present application includes a housing, a vibration system, and a magnetic circuit system. The housing is provided with a support plate, and the support plate is provided with a first through hole; the vibration system includes a sound A ring, a first diaphragm, a diaphragm, and a second diaphragm arranged at intervals along the short axis of the voice coil, a hollow first connecting member sandwiched between the first diaphragm and the diaphragm, And a second hollow connecting member sandwiched between the diaphragm and the second diaphragm; the first diaphragm and the second diaphragm are both fixed on the housing, and the diaphragm is fixed On the supporting plate and covering the first through hole, the first diaphragm is connected to the voice coil; the first diaphragm is connected to the housing, the supporting plate and the diaphragm Surrounded to form a first diaphragm front cavity, the diaphragm is provided with a second through hole, the second diaphragm is provided with a third through hole, and the first diaphragm front cavity sequentially passes through the first connection The hollow structure of the component, the second through hole, the hollow structure of the second connecting piece, and the third through hole are in communication with the outside. Through the above method, it is possible to push more air to produce sound under the same amplitude, increase the effective radiation area of the micro speaker, and achieve stronger bass performance; at the same time, under the same bass output, the impact on the micro speaker is reduced. The amplitude requirement not only helps to extend the life of the micro-speaker, but also reduces the volume requirement on the back cavity of the mobile phone.

Description of the drawings

FIG. 1 is a schematic diagram of the overall structure of a micro speaker according to an embodiment of the application;

2 is a schematic diagram of an exploded structure of a micro speaker according to an embodiment of the application;

Fig. 3 is a schematic cross-sectional structure view along the A-A direction in Fig. 1;

Fig. 4 is a schematic cross-sectional structure view along the B-B direction in Fig. 1;

Fig. 5 is a schematic cross-sectional structure view along the direction C-C in Fig. 1;

FIG. 6 is a schematic diagram 1 of a part of the structure of a micro speaker according to an embodiment of the application;

FIG. 7 is a schematic diagram of a part of the structure of a micro speaker according to an embodiment of the application;

Reference signs: micro speaker 100; housing 1; accommodating space 10; first side wall 11; first assembly port 111; second assembly port 112; second side wall 12; support plate 13; first through hole 131; The second joint ring 14; the first joint ring 15; the third fixing part 16; the vibration system 2; the voice coil 21; the first diaphragm 22; the first sound diaphragm 221; the first dome 222; the diaphragm 23; Hole 231; second diaphragm 24; third through hole 241; second sound diaphragm 242; second dome 243; first connecting member 25; support post 251; first fixing portion 252; second fixing portion 253; support Arm 2531; support base 2532; second connector 26; skeleton assembly 27; skeleton 271; first joint 271a; second joint 271b; first main body 271c; third joint 271d; flexible circuit board assembly 28; Flexible circuit board 281; second body portion 281a; elastic connecting portion 281b; holding portion 281c; magnetic circuit system 3; first magnet assembly 31; first magnet 311; pole core & second magnet 312; second magnet assembly 32; First splint 33; Second splint 34.

Embodiments of the present invention

The application will be further described below in conjunction with the drawings and implementations.

1-7, an embodiment of the present application provides a micro speaker 100, including a housing 1, a vibration system 2 having a receiving space 10, and received in the receiving space 10 for driving the vibration System 2 Vibrating magnetic circuit system 3. Wherein, the housing 1 includes a first side wall 11 and a second side wall 12 bent and extended from the edge of the first side wall 11. The first side wall 11 and the second side wall 12 surround the receiving space 10. The housing 1 further includes a supporting plate 13 extending from the second side wall 12 into the receiving space 10, and the supporting plate 13 is provided with a first through hole 131.

Specifically, the vibration system 2 includes a voice coil 21, a first diaphragm 22, a diaphragm 23, and a second diaphragm 24 that are arranged at intervals along the short axis of the voice coil 21, and are sandwiched between the first diaphragm. The first connecting member 25 between the diaphragm 22 and the diaphragm 23 and the second connecting member 26 sandwiched between the diaphragm 23 and the second diaphragm 24. The first plane (the XY plane as shown in FIG. 4) formed by the long axis side and the short axis side of the voice coil 21 and the plane where the first diaphragm 22 is located, the plane where the diaphragm 23 is located, and the The planes of the second diaphragm 24 are perpendicular to each other. The magnetic circuit system 3 includes a first magnet assembly 31 and a second magnet assembly 32 arranged at intervals along a direction perpendicular to the first plane, and the voice coil 21 is arranged on the first magnet assembly 31 and the second magnet assembly 31. Between the magnet assembly 32.

In this application, the voice coil 21 and the magnetic circuit system 3 are arranged in the above-mentioned manner, so that the micro-speaker 100 can achieve an ultra-large low-frequency amplitude Xmax>1.0mm, which improves the driving force (Bli) of the speaker product and achieves lower power consumption. Under conditions, to achieve super bass performance.

Further, the first diaphragm 22 is accommodated in the accommodating space 10 and connected to the voice coil 21, the first diaphragm 22 is fixed on the second side wall 12, and the second diaphragm 22 is The film 24 is held on the end of the second side wall 12 away from the first side wall 11. The diaphragm 23 is fixed on the supporting plate 13 and covers the first through hole 131. The first diaphragm 22 and the second side wall 12, the supporting plate 13 and the diaphragm 23 surround the first diaphragm front cavity. The second diaphragm 24 and the outer peripheral wall of the second side wall 12, the supporting plate 13, the diaphragm 23, and the second connecting member 26 are enclosed to form a closed second diaphragm rear cavity. The diaphragm 23 is provided with a second through hole 231, the second diaphragm 24 is provided with a third through hole 241, and the first diaphragm front cavity sequentially passes through the hollow structure of the first connecting member 25, The second through hole 231, the hollow structure of the second connecting member 26, and the third through hole 241 communicate with the outside.

In the present application, a first diaphragm formed by the first diaphragm 22, the diaphragm 23, the second side wall 12, and the supporting plate 13 is arranged in the housing space 10 of the housing 1 to communicate with the outside world. The front cavity of the diaphragm makes it possible to push more air to produce sound under the same amplitude, increase the effective radiation area of the micro speaker 100, and achieve stronger bass performance; at the same time, under the same bass output, it reduces the impact on the The amplitude requirement of the micro speaker 100 not only helps to extend the life of the micro speaker 100, but also reduces the volume requirement on the back cavity of the mobile phone. It should be noted that in other embodiments of the present application, the first diaphragm front cavity may be connected to the outside in other ways, for example, a through hole communicating with the outside is provided at a corresponding position of the second side wall 12, etc. It is understandable that the above all belong to the protection scope of this application.

Optionally, the first connecting member 25 includes a hollow support column 251, a first fixing portion 252 bent and extended from the edge of the support column 251, and relatively spaced apart from the support column 251 away from the Two second fixing parts 253 at the end of the first fixing part 252. The second fixing portion 253 includes a supporting arm 2531 extending from the edge of the supporting column 251 and a supporting platform 2532 extending from the end of the supporting arm 2531 away from the supporting column 251 by bending. The first fixing portion 252 is sandwiched between the support column 251 and the inner peripheral side of the diaphragm 23, and the support platform 2532 is sandwiched between the support arm 2531 and the first diaphragm 22. Between the sides.

Optionally, the outer circumferential side of the diaphragm 23 covers the first through hole 131, and the inner circumferential side of the diaphragm 23 is sandwiched between the first connecting member 25 and the second connecting member 26, so The second through hole 231 is provided on the inner peripheral side of the diaphragm 23. The diaphragm 23 further includes a first folding ring portion a protruding in the direction of the second diaphragm 24, which can increase the volume of the front cavity of the first diaphragm, thereby increasing the effective radiation area of the micro speaker 100 .

Optionally, in this embodiment, the housing 1 further includes a first joint ring 15 bent and extended from the edge of the support plate 13, and a first joint ring 15 away from the support plate 13 from the first joint ring 15 The third fixing portion 16 is bent and extended at the end. The first joining ring 15 is fixedly arranged on the second side wall 12, and the third fixing portion 16 is sandwiched between the second diaphragm 24 and the second side wall 12. The outer peripheral wall of the second diaphragm 24 and the first joining ring 15, the supporting plate 13, the diaphragm 23 and the second connecting member 26 form the second diaphragm rear cavity.

Optionally, in this embodiment, the housing 1 further includes a second joint ring 14 fixedly arranged on the second side wall 12 for holding the first diaphragm 22. The magnetic circuit system 3 also includes a first clamping plate 33 and a second clamping plate 34 spaced apart along the short axis of the voice coil 21 (the Y direction as shown in FIGS. 3-5), and the first magnet assembly 31 and the second magnet assembly 32 are arranged between the first clamping plate 33 and the second clamping plate 34. The first clamping plate 33 is fixedly arranged on the first side wall 11, and the second joining ring 14 is sandwiched between the second clamping plate 34 and the first diaphragm 22. By arranging the first magnet assembly 31 and the second magnet assembly 32 between the upper clamping plate 33 and the lower clamping plate 34 to fix the two magnet assemblies 31 and 32, the magnetic components can be effectively protected when the product falls. Road system structure enhances the product’s resistance to fall.

Optionally, in this embodiment, the vibration system 2 further includes a skeleton assembly 27 coupled to one side of the first diaphragm 22 for connecting the voice coil 21 and the first diaphragm 22, so The frame assembly 27 includes two frames 271 arranged at opposite intervals along the direction of the long axis of the voice coil 21 (the X direction as shown in FIG. 4), and the frame 271 includes Spaced first joint portions 271a and second joint portions 271b for clamping the short axis side of the voice coil 21, and a first body portion connecting the first joint portion 271a and the second joint portion 271b 271c, the first main body portion 271c is connected to the first diaphragm 22. The short axis side of the voice coil 21 is clamped by the first joint portion 271a and the second joint portion 271b together, and the voice coil 21 is suspended on the first magnet assembly 31 and the second magnet assembly It is possible to prevent the voice coil 21 from shaking when moving back and forth between 32, and improve the motion stability of the vibration system 2.

Further, the first joint portion 271a is connected to the outer periphery of the voice coil 21, and the second joint portion 271b is connected to the inner periphery of the voice coil 21, as shown in FIG. 4, which can avoid the The voice coil 21 shakes when moving back and forth. It should be noted that the length of the second joint portion 271b is designed according to the length of the short side of the inner periphery of the voice coil 21. The length of the first joint portion 271a is not limited to that shown in this embodiment, one end is connected to the outer periphery of the voice coil 21, and the other end extends to the first diaphragm 22. The joint portion 271a also belongs to the protection scope of the present application.

Optionally, the first body portion 271c is attached to the voice coil 21 to provide more support points for the voice coil 21, thereby further improving the motion stability of the voice coil 21.

Optionally, in this embodiment, the frame 271 further includes a third joint portion 271d bent and extended from the edge of the first main body portion 271c, and the third joint portion 271d is fixed to the first vibration The inner edge of the film 22 is close to the first side wall 11 side.

Optionally, the first diaphragm 22 may be a complete sound diaphragm, or the sound diaphragm may be matched with the dome. In this embodiment, the first diaphragm 22 includes a first sound diaphragm 221 and a first dome 222 sandwiched between the first sound diaphragm 221 and the first connecting member 25. The first dome 222 is attached to the inner peripheral side of the first sound membrane 221, the outer peripheral side of the first sound membrane 221 is fixed on the second joint ring 14, and the first sound membrane 221 It also includes a second folding ring portion b protruding toward the second diaphragm 24.

Optionally, the second diaphragm 24 may be a complete sound diaphragm, or may be a sound diaphragm matched with a dome. In this embodiment, the second diaphragm 24 includes a second sound diaphragm 242, and a second dome 243 attached to the inner peripheral side of the second sound diaphragm 242 away from the second side wall 12, The second sound film 242 further includes a third folding ring portion c protruding away from the second side wall 12.

Specifically, the vibration system 2 further includes a flexible circuit board assembly 28 fixedly arranged on the first side wall 11, and the flexible circuit board assembly 28 includes two relatively spaced apart along the long axis of the voice coil 21. The flexible circuit board 281 is provided, and both of the flexible circuit boards 281 are electrically connected to the voice coil 21.

Optionally, in this embodiment, the flexible circuit board 281 includes a second body portion 281a connected to the voice coil 21, an elastic connecting portion 281b connected to one end of the second body portion 281a, and The holding portion 281c connected to the elastic connecting portion 281b. The holding portion 281c is fixedly arranged on the first side wall 11, and the other end of the second main body portion 281a is connected to the end of the frame 271 on the same side close to the first side wall 11. More specifically, the other end of the second main body portion 281a is connected to the end of the first main body portion 271c on the same side close to the first side wall 11.

Optionally, in this embodiment, as shown in FIG. 7, the first side wall 11 is provided with a first assembly opening 111 and a second assembly opening symmetrically provided on both sides of the first assembly opening 111 112. The first clamping plate 33 is embedded in the first assembly opening 111, and the holding portion 281c is embedded in the corresponding second assembly opening 112, respectively.

Optionally, in this embodiment, the first magnet assembly 31 is composed of five elements with a magnetic permeability function. The five magnetically conductive elements include three first magnets 311 arranged at intervals along the short axis of the voice coil 21 and pole cores 312 respectively arranged between adjacent first magnets 311 , Or the second magnets 312 respectively arranged between the adjacent first magnets 311. It should be noted that in some other embodiments, the first magnet assembly 31 is composed of three elements with a magnetic conductivity function. In other other embodiments, the first magnet assembly 31 is composed of only one element with a conductive function. Composition of magnetically functional components. It is understandable that the above all belong to the protection scope of this application.

Optionally, in this embodiment, the structure of the second magnet assembly 32 is the same as the structure of the second magnet assembly 31.

The above are only the implementation manners of this application. It should be pointed out here that for those of ordinary skill in the art, improvements can be made without departing from the creative concept of this application, but these all belong to this application. The scope of protection.

Claims

1. A micro speaker, characterized in that it comprises a housing with a housing space, a vibration system, and a magnetic circuit system housed in the housing space, the housing including a first side wall, A second side wall extending from the edge of the side wall by bending, and a supporting plate extending from the second side wall into the receiving space, the supporting plate is provided with a first through hole;

The first diaphragm and the second side wall, the support plate, and the diaphragm are enclosed to form a first diaphragm front cavity, the diaphragm is provided with a second through hole, and the second diaphragm is A third through hole is provided, and the first diaphragm front cavity sequentially passes through the hollow structure of the first connecting piece, the second through hole, the hollow structure of the second connecting piece, and the third through hole Connect with the outside world;

2. The micro-speaker according to claim 1, wherein the first connecting member comprises a hollow support column, a first fixing part bent and extended from the edge of the support column, and relatively spaced apart from each other. Two second fixing portions of the support column far from the end of the first fixing portion, the second fixing portion includes a support arm extending from the edge of the support column and an end bent away from the support column from the support arm A support platform that is folded and extended; the first fixing portion is sandwiched between the support column and the inner peripheral side of the diaphragm, and the support platform is sandwiched between the support arm and the first diaphragm Between the sides.

3. The micro speaker according to claim 1, wherein the outer peripheral side of the diaphragm is provided on the first through hole, and the inner peripheral side of the diaphragm is sandwiched between the first connecting member and the first through hole. Between the second connecting members, the second through hole is provided on the inner peripheral side of the diaphragm, and the diaphragm further includes a first folding ring portion protruding toward the second diaphragm.

4. The micro speaker according to claim 1, wherein the housing further comprises a first joint ring bent and extended from the edge of the support plate, and a first joint ring away from the support from the first joint ring. A third fixing part extending from the end of the plate; the first joining ring is fixed on the second side wall, and the third fixing part is sandwiched between the second diaphragm and the second side wall between.

5. The micro speaker according to claim 1, wherein the housing further comprises a second joint ring fixed on the second side wall for holding the first diaphragm.

6. The micro speaker according to claim 1, wherein the vibration system further comprises a skeleton assembly coupled to one side of the first diaphragm for connecting the voice coil and the first diaphragm, The skeleton assembly includes two skeletons arranged at relatively intervals along the long axis side of the voice coil, and the skeleton includes spacers arranged at intervals along the long axis side of the voice coil for clamping the short axis side of the voice coil. A first joint part and a second joint part, and a first main body part connecting the first joint part and the second joint part, and the first main body part is connected to the first diaphragm.

7. The micro speaker according to claim 1, wherein the first diaphragm comprises a first sound film, and a first ball sandwiched between the first sound film and the first connecting member The top, the first dome is attached to the inner peripheral side of the first sound membrane, and the first sound membrane includes a second folding ring portion protruding in the direction of the second diaphragm.

8. The micro speaker according to claim 1, wherein the second diaphragm comprises a second sound film, and a side away from the second side wall attached to the inner peripheral side of the second sound film The second dome; the second sound film includes a third ring portion protruding away from the second side wall direction.

9. The micro speaker according to claim 5, wherein the vibration system further comprises a flexible circuit board assembly fixedly arranged on the first side wall, and the flexible circuit board assembly includes two edges along the The flexible circuit boards are arranged at relatively intervals in the direction of the long axis of the voice coil, and the flexible circuit boards are electrically connected to the voice coil.

10. The micro speaker according to claim 9, wherein the magnetic circuit system further comprises a first clamping plate and a second clamping plate spaced apart along the short axis of the voice coil, the first magnet assembly and The second magnet assembly is arranged between the first splint and the second splint, the first splint is fixedly arranged on the first side wall, and the second coupling ring is sandwiched between the first splint and the second splint. Between the two splints and the first diaphragm.

11. The micro speaker according to claim 10, wherein the first side wall is provided with a first assembling opening and a second assembling opening symmetrically arranged on both sides of the first assembling opening, the first assembling opening A clamping plate is embedded in the first assembly opening, and part of the structure of the flexible circuit board is respectively embedded in the corresponding second assembly opening.