Electroacoustic transducer

Abstract

The application discloses an electro-acoustic conversion device, which comprises a shell, a magnetic circuit system, a vibration system, a first conductive circuit and a second conductive circuit. The magnetic circuit system is arranged in the shell and has a magnetic gap. The vibration system is arranged in the shell and comprises two vibration sound production components and a voice coil. The two vibration sound production components are arranged on opposite sides of the shell. Each vibration sound production component comprises a diaphragm and a piezoelectric sheet arranged on the diaphragm. The voice coil is arranged in the magnetic gap and drives the vibration sound production components to vibrate. The first conductive circuit is electrically connected with the voice coil, and the second conductive circuit is electrically connected with the piezoelectric sheet. The technical scheme of the application can make the electro-acoustic conversion device have a higher sound pressure level output in the full frequency range from low frequency to high frequency.

Description

Technical Field

[0001] This invention relates to the field of electroacoustic conversion devices, and particularly to an electroacoustic conversion device. Background Technology

[0002] As people's pursuit of sound quality in smart devices increases, they demand that electroacoustic converters provide high sound pressure level response across the entire frequency range. However, conventional dynamic electroacoustic converters, due to their structural limitations, typically experience a significant and rapid drop in sound pressure level at high frequencies, making it difficult to achieve high sound pressure level output across the entire frequency range from low to high frequencies. Summary of the Invention

[0003] The main objective of this invention is to provide an electroacoustic conversion device that can output a high sound pressure level across the entire frequency range from low to high frequencies.

[0004] To achieve the above objectives, the electroacoustic conversion device proposed in this invention includes:

[0005] case;

[0006] A magnetic circuit system is provided in the housing and has a magnetic gap;

[0007] A vibration system, disposed in the housing, includes two vibration-generating components and a voice coil. The two vibration-generating components are respectively disposed on opposite sides of the housing. Each vibration-generating component includes a diaphragm and a piezoelectric element disposed on the diaphragm. The voice coil is disposed in the magnetic gap and drives the vibration-generating component to vibrate.

[0008] A first conductive line and a second conductive line, wherein the first conductive line is electrically connected to the voice coil and the second conductive line is electrically connected to the piezoelectric element.

[0009] Optionally, the housing is provided with a first conductive terminal and a second conductive terminal, the second conductive line is provided on the inner side of the diaphragm and electrically connected to the first conductive terminal and the piezoelectric sheet, and the voice coil is electrically connected to the second conductive terminal.

[0010] Optionally, the second conductive line is fixedly connected to the piezoelectric sheet by the first conductive adhesive.

[0011] Optionally, the second conductive line is fixedly connected to the first conductive terminal by a second conductive adhesive.

[0012] Optionally, the first conductive terminal has a first conductive protrusion protruding towards the second conductive line.

[0013] Optionally, the second conductive line has a second conductive protrusion protruding towards the first conductive terminal.

[0014] Optionally, the housing is provided with an adhesive storage tank, one end of the first conductive terminal is disposed in the adhesive storage tank, and the second conductive adhesive is filled in the adhesive storage tank.

[0015] Optionally, the housing includes a front cover, a middle frame, and a rear cover connected to each other. The front cover and the rear cover are opposite to each other and have a through-hole. The two vibration sound-generating components are respectively fixed to the front cover and the rear cover and cover the through-hole. The magnetic circuit system includes a magnet disposed on the front cover. The magnet and the rear cover are distributed at intervals along the vibration direction of the diaphragm. The magnetic gap is formed on the side of the magnet near the rear cover.

[0016] Optionally, the back cover may be made of a magnetic material or a non-magnetic material.

[0017] Optionally, the voice coil is configured as a flat voice coil, and the magnet includes two magnets, which are respectively disposed at opposite ends of the front cover along a first direction. Each magnet is configured as a Helbeck array structure, and each magnet includes a first magnetic block, a second magnetic block, and a third magnetic block distributed sequentially along the first direction. The magnetization direction of the first magnetic block is set along the vibration direction of the diaphragm and is set opposite to the magnetization direction of the third magnetic block. The magnetization direction of the second magnetic block is set from the third magnetic block toward the first magnetic block.

[0018] Optionally, the voice coil is configured as a flat voice coil, and the vibration system further includes a deformable commutator bracket. The flat voice coil drives the vibration sound-generating component to vibrate through the commutator bracket. The commutator bracket has a first mounting part and a second mounting part that are movably connected. The first mounting part is connected to the flat voice coil, and the second mounting part is connected to the vibration sound-generating component. When the first mounting part is driven by the flat voice coil to vibrate along a first direction, the second mounting part can drive the vibration sound-generating component to vibrate along a second direction, which is orthogonal to the first direction.

[0019] Optionally, there are two first mounting portions and two second mounting portions, with two second mounting portions disposed between the two first mounting portions. One second mounting portion is connected to one of the vibration-generating sound components, and the other second mounting portion is connected to another of the vibration-generating sound components.

[0020] Optionally, the vibration system further includes a flexible connector, through which the two first mounting portions and the two second mounting portions are movably connected, and the flexible connector forms a bent portion between the two first mounting portions and the two second mounting portions.

[0021] Optionally, the flexible connector is heat-pressed onto the surfaces of the first mounting portion and the second mounting portion, or the flexible connector is injection-molded onto the first mounting portion and the second mounting portion.

[0022] Optionally, both the first mounting portion and the second mounting portion have multiple filling holes at their edges for filling by the flexible connector.

[0023] Optionally, the first mounting part and the second mounting part are made of metal or plastic.

[0024] Optionally, the flexible connector may be made of rubber or silicone.

[0025] Optionally, two flat voice coils are provided, which are respectively connected to the two first mounting parts. The two flat voice coils are respectively located at opposite ends of the commutation bracket and have opposite vibration directions.

[0026] Optionally, the reversing bracket includes multiple plate portions and multiple bending portions. The multiple plate portions are spaced apart along the first direction, and adjacent plate portions are connected by the bending portions. The multiple plate portions include a first plate portion, a second plate portion, a third plate portion, a fourth plate portion, and a fifth plate portion arranged sequentially along the first direction. Two first mounting portions are disposed on the first plate portion and the fifth plate portion, and two second mounting portions are disposed on the third plate portion.

[0027] Optionally, the reversing bracket is provided with at least one partition hole, the partition hole extends along the first direction and extends at least from the second plate portion to the fourth plate portion, the at least one partition hole divides the third plate portion into at least two third sub-plate segments, one third sub-plate segment forms a second mounting portion, and the other third sub-plate segment forms another second mounting portion.

[0028] Optionally, two partition holes are provided, and the two partition holes are distributed at intervals along the extension direction of the bending portion. The two partition holes divide the third plate into three third sub-plate segments. The third sub-plate segment located in the middle forms a second mounting portion, and the other two third sub-plate segments together form another second mounting portion.

[0029] Optionally, the diaphragm includes a planar portion and a folded ring portion disposed on the outer periphery of the planar portion. A membrane through hole is provided in the middle of the planar portion. The periphery of the piezoelectric sheet is connected to the edge of the membrane through hole. The second mounting portion is disposed on the inner side of the piezoelectric sheet.

[0030] Optionally, the vibration system further includes two connecting rods, and the two flat voice coils are respectively connected to the two first mounting portions through the two connecting rods. The connecting rods include a main rod section and auxiliary rod sections disposed at both ends of the main rod section. The two ends of the flat voice coil are respectively disposed at one of the auxiliary rod sections, and the main rod section is disposed at the first mounting portion.

[0031] Optionally, the vibration system further includes at least two centering springs disposed on the housing, wherein the elastic action directions of the at least two centering springs are arranged facing each other and are respectively connected to the two connecting rods.

[0032] In this invention, the electroacoustic conversion device simultaneously possesses both a moving-coil and a piezoelectric sound-generating structure. The voice coil and piezoelectric element receive electrical signals of different frequency bands through a first conductive line and a second conductive line, respectively. Thus, when a mid-to-high frequency signal is input, the piezoelectric element deforms to generate sound, while when a low-frequency signal is input, the voice coil vibrates under the influence of a magnetic field, generating sound. This allows the electroacoustic conversion device to output a high sound pressure level across the entire frequency range from low to high frequencies, achieving a high-performance, ultra-wideband electroacoustic conversion device. Furthermore, by simultaneously emitting sound from two opposing vibrating components, when this electroacoustic conversion device is applied to devices such as mobile phones, computers, VR glasses, and AR glasses, it can effectively eliminate vibration. For example, when applied to the temples of VR glasses, it can reduce the negative impact of temple vibration during sound generation, effectively eliminating temple vibration. Attached Figure Description

[0033] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0034] Figure 1 This is a schematic diagram of the structure of an embodiment of the electroacoustic conversion device of the present invention from a frontal view.

[0035] Figure 2 for Figure 1 A schematic diagram of the electroacoustic conversion device from a rear view.

[0036] Figure 3 for Figure 1 Front view of the electroacoustic conversion device in the middle;

[0037] Figure 4 for Figure 3 A cross-sectional view of the electroacoustic conversion device at point AA;

[0038] Figure 5 for Figure 4 A partially enlarged cross-sectional view of the electroacoustic conversion device in the diagram;

[0039] Figure 6 for Figure 4 A schematic diagram showing the magnetization direction of the magnet in the electroacoustic conversion device.

[0040] Figure 7 for Figure 4 Exploded view of a component of the electroacoustic conversion device in China;

[0041] Figure 8 for Figure 7 Exploded view of another component of the electroacoustic conversion device;

[0042] Figure 9 for Figure 7 A structural diagram of the middle frame from the front view.

[0043] Figure 10 for Figure 7 A structural diagram of the middle frame from a rear view.

[0044] Figure 11 for Figure 9 The main view of the middle frame;

[0045] Figure 12 for Figure 11 The cross-sectional view of the middle frame at BB;

[0046] Figure 13 for Figure 7 A schematic diagram of the installation of the diaphragm, piezoelectric element, and second conductive circuit in the circuit.

[0047] Figure 14 for Figure 7 A schematic diagram of the reversing bracket in the diagram;

[0048] Figure 15 for Figure 14 Front view of the reversing bracket in the middle;

[0049] Figure 16 for Figure 15 A schematic diagram of all plates of the reversing bracket in the diagram;

[0050] Figure 17 for Figure 15 A cross-sectional view of the reversing bracket at CC;

[0051] Figure 18 This is a front view of another embodiment of the reversing bracket;

[0052] Figure 19 for Figure 18 A schematic diagram of all plates of the reversing bracket in the diagram;

[0053] Figure 20 for Figure 18 A cross-sectional view of the reversing bracket at DD in the middle;

[0054] Figure 21 for Figure 7 A schematic diagram of the centering spring in the middle.

[0055] Explanation of icon numbers:

[0056]

[0057] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0058] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0059] It should be noted that if the embodiments of the present invention involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of the components in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicators will also change accordingly.

[0060] In this invention, unless otherwise explicitly specified and limited, the terms "connection," "fixed," etc., should be interpreted broadly. For example, "fixed" can mean a fixed connection, a detachable connection, or an integral part; it can mean a mechanical connection or an electrical connection; it can mean a direct connection or an indirect connection through an intermediate medium; it can mean the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0061] Furthermore, if the embodiments of this invention involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the meaning of "and / or" throughout the text includes three parallel solutions; for example, "A and / or B" includes solution A, solution B, or a solution where both A and B are satisfied simultaneously. Furthermore, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this invention.

[0062] This invention proposes an electroacoustic conversion device, please refer to... Figures 1 to 5 In one embodiment of the present invention, the electroacoustic conversion device includes:

[0063] Casing 10;

[0064] A magnetic circuit system 20 is disposed in the housing 10 and has a magnetic gap 20a;

[0065] A vibration system, located in the housing 10, includes two vibration-generating components 30 and a voice coil 40. The two vibration-generating components 30 are respectively disposed on opposite sides of the housing 10. Each vibration-generating component 30 includes a diaphragm 31 and a piezoelectric sheet 32 ​​disposed on the diaphragm 31. The voice coil 40 is disposed in the magnetic gap 20a and drives the vibration-generating component to vibrate.

[0066] The first conductive line 51 and the second conductive line 52 are electrically connected. The first conductive line 51 is electrically connected to the voice coil 40, and the second conductive line 52 is electrically connected to the piezoelectric element 32.

[0067] In this invention, the electroacoustic conversion device simultaneously possesses both a moving-coil sound-generating structure and a piezoelectric sound-generating structure. The voice coil 40 and the piezoelectric element 32 receive electrical signals of different frequency bands through the first conductive line 51 and the second conductive line 52, respectively. Thus, when the piezoelectric element 32 receives a mid-to-high frequency signal input, it deforms to generate sound. When the voice coil 40 receives a low-frequency signal input, it drives the diaphragm 31 to vibrate under the influence of a magnetic field, generating sound. This allows the electroacoustic conversion device to output a high sound pressure level across the entire frequency range from low to high frequencies, achieving a high-performance ultra-wideband electroacoustic conversion device. Furthermore, by setting two opposing vibrating sound-generating components to generate sound simultaneously, when this electroacoustic conversion device is applied to devices such as VR glasses or AR glasses, for example, on the temples of VR glasses, it can reduce the negative impact of temple vibration during sound generation, effectively eliminating temple vibration.

[0068] Please refer to Figure 4 and 5 In one embodiment, the voice coil 40 is configured as a flat voice coil 40, and the width direction of the flat voice coil is approximately parallel to the width direction of the diaphragm 31. This reduces the thickness of the electroacoustic conversion device in the vibration direction of the diaphragm 31, thereby facilitating its thinner design. Of course, in other embodiments, the voice coil can also be configured as a cylindrical voice coil.

[0069] Specifically, the shape of the flat voice coil 40 can be racetrack-shaped, elliptical ring-shaped, circular ring-shaped, square ring-shaped, etc. For example, the flat voice coil 40 can be generally elongated, meaning that its length is longer in one radial direction and narrower in another perpendicular radial direction. Racetrack-shaped, elliptical ring-shaped, and rectangular ring-shaped can be considered as elongated forms. Correspondingly, the magnetic gap 20a can be elongated. The length of the magnetic gap 20a corresponds to the length of the flat voice coil 40, the width of the magnetic gap 20a corresponds to the width of the flat voice coil 40, and the height of the magnetic gap 20a corresponds to the height of the flat voice coil 40. In this way, the flat voice coil 40 can fully utilize the space of the magnetic gap 20a to obtain better driving force. For details, please refer to... Figure 5 and 7 The flat voice coil 40 has a long axis segment 40a and a short axis segment 40b. The long axis segment 40a extends along the length direction of the magnetic gap 20a, the short axis segment 40b extends along the width direction of the magnetic gap 20a, and the axial direction of the flat voice coil 40 extends along the height direction of the magnetic gap 20a. This can greatly improve the space utilization.

[0070] Please refer to Figures 9 to 13 In one embodiment, the housing 10 is provided with a first conductive terminal 14 and a second conductive terminal 15. A second conductive line 52 is disposed on the inner side of the diaphragm 31 and electrically connects the first conductive terminal 14 and the piezoelectric sheet 32. The voice coil 40 is electrically connected to the second conductive terminal 15. Specifically, in this embodiment, the second conductive line 52 can be electroplated, coated, or embedded on the diaphragm 31, or it can be etched from a flexible printed circuit board (FPC) composited on the diaphragm 31. Further, the diaphragm 31 includes a polymer material layer, and the second conductive line 52 can be bonded to the polymer material layer, or it can be etched from a flexible printed circuit board composited on the polymer material layer. For ease of manufacturing, the diaphragm 31 can be pressed from the diaphragm 31 material with the second conductive line 52 already laid on it. Thus, placing the second conductive line 52 on the inner side of the diaphragm 31 facilitates connection with the first conductive terminal 14 and also protects the second conductive line 52. Of course, in some embodiments, the second conductive line 52 can also be disposed on the outer side of the diaphragm 31. In other embodiments, the second conductive line 52 may be configured as a conductive line structure that can move freely.

[0071] Please refer to Figure 1 , 7 In one embodiment, the housing 10 has a welding boss on one side, and two sets of first conductive terminals 14 corresponding to the two piezoelectric pieces 32 are respectively provided on this side. One end of one set of first conductive terminals 14 is exposed on the front side (i.e., the top side) of the housing 10 for connection to the second conductive line 52 located on the front side, and the other end is exposed on the front side of the welding boss to form a set of first pads 16. One end of the other set of first conductive terminals 14 is exposed on the rear side (i.e., the bottom side) of the housing 10 for connection to the second conductive line 52 located on the rear side, and the other end is exposed on the front side of the welding boss to form another set of first pads 16. One end of the second conductive terminal 15 is exposed on the rear side of the housing 10 for connection to the first conductive line 51, and the other end is exposed on the front side of the housing 10 to form a second pad 17. The first pad 16 and the second pad 17 are both used for external circuit soldering. That is, the first pad 16 and the second pad 17 are used for inputting medium- and high-frequency signals and low-frequency signals, respectively. This facilitates the installation and fixing of the vibration system to the housing 10 and completes the electrical connection.

[0072] Please refer to Figures 9 to 12 In one embodiment, the housing 10 has an adhesive storage groove 10a corresponding to the first conductive terminal 14. One end of the first conductive terminal 14 is disposed in the adhesive storage groove 10a. The second conductive adhesive fills the adhesive storage groove 10a and fixes the second conductive line 52 and the first conductive terminal 14. In this way, good conductivity between the second conductive line 52 and the first conductive terminal 14 can be guaranteed, and installation is simple. Of course, in other embodiments, the second conductive line 52 can also be welded and fixed to the first conductive terminal 14.

[0073] Please refer to Figures 9 to 13 In one embodiment, the first conductive terminal 14 has a first conductive protrusion 141 protruding towards the second conductive line 52, and the second conductive line 52 has a second conductive protrusion 521 protruding towards the first conductive terminal 14. This increases the conductive area, thereby ensuring good conductivity between the second conductive line 52 and the first conductive terminal 14. Specifically, the second conductive protrusion 521 and the second conductive line 52 are integrally stamped, and the first conductive protrusion 141 and the first conductive terminal 14 are integrally stamped. Of course, in some embodiments, the second conductive protrusion 521 may be formed and then fixed to the second conductive line 52, and the first conductive protrusion 141 may be formed and then fixed to the first conductive terminal 14. In other embodiments, only the first conductive protrusion 141 or the second conductive protrusion 521 may be provided, or neither may be provided.

[0074] In one embodiment, the second conductive line 52 is fixedly connected to the piezoelectric sheet 32 ​​using a first conductive adhesive. This ensures good conductivity between the second conductive line 52 and the piezoelectric sheet 32 ​​and simplifies installation. Alternatively, the second conductive line 52 can also be fixedly connected to the first conductive terminal 14 using a second conductive adhesive. This also ensures good conductivity between the second conductive line 52 and the first conductive terminal 14 and simplifies installation.

[0075] Please refer to Figures 5 to 8 In one embodiment, the housing 10 includes a front cover 11, a middle frame 12, and a rear cover 13. The front cover 11 is connected to the top side of the middle frame 12, and the rear cover 13 is connected to the bottom side of the middle frame 12. The front cover 11 and the rear cover 13 are opposite to each other and have a through-hole 11a. Two diaphragms 31 are respectively fixed to the front cover 11 and the rear cover 13 and cover the through-hole 11a. The magnetic circuit system 20 includes a magnet 21 disposed on the front cover 11. The magnet 21 and the rear cover 13 are spaced apart along the vibration direction of the diaphragm 31, and the magnetic gap is formed on the side of the magnet near the rear cover. In this way, the size of the electroacoustic conversion device in the vibration direction of the diaphragm 31, that is, in the thickness direction, can be reduced, thereby facilitating the thin design of the electroacoustic conversion device. Optionally in this embodiment, the first conductive terminal 14 and the second conductive terminal 15 are both injection molded on the middle frame 12. Of course, in other embodiments, the magnet can also be disposed on the rear cover, and the magnetic gap can be formed on the side of the magnet near the front cover.

[0076] Please refer to Figure 6 In one embodiment, the voice coil is configured as a flat voice coil, and two magnets 21 are respectively disposed at opposite ends of the front cover 11 along a first direction. Each magnet 21 is configured as a Helbeck array structure. Specifically, each magnet 21 includes a first magnetic block 21a, a second magnetic block 21b, and a third magnetic block 21c distributed sequentially along the first direction. The magnetization direction of the first magnetic block 21a is set along the vibration direction of the diaphragm 31 (i.e., the second direction) and is opposite to the magnetization direction of the third magnetic block 21c. The magnetization direction of the second magnetic block 21b is set from the third magnetic block 21c toward the first magnetic block 21a. In this way, the magnetic field strength can be increased within a limited space, and combined with the flat structure characteristics of the flat voice coil, it is beneficial to the thin design of the electroacoustic conversion device. Furthermore, the two ends of the diaphragm 31 are simultaneously driven by two flat voice coils 40 moving in opposite directions, which can increase the amplitude of the vibration response, thereby improving the response sensitivity and sound pressure level of the moving coil sound generation structure. Of course, in other embodiments, the magnet 21 can also be configured as a conventional structure, for example, with only one uniform magnetization direction.

[0077] Please refer to Figure 6In an embodiment where the magnets are configured as a Hellbeck array, optionally, two magnets 21 are provided, spaced apart along the front-rear direction of the housing. A first magnet 21a is positioned near the center of the diaphragm 31, and the two first magnets 21a have opposite magnetic poles (i.e., the same magnetization direction). Two third magnets 21c have opposite magnetic poles, and two second magnets 21b have opposite magnetization directions. One long axis segment 40a of the flat voice coil is located between the two first magnets 21a, and the other long axis segment 40a is located between the two third magnets 21c. It should be noted that opposite magnetic poles mean that the ends of the two magnets that are close to each other are the N pole and the S pole, respectively. This increases the magnetic field strength within the magnetic gap 20a and improves the response sensitivity of the flat voice coil 40. Of course, in other embodiments, the flat voice coil may have only one long axis segment 40a located between the two first magnets 21a (or the two third magnets 21c), with the other long axis segment 40a located outside the magnetic gap 20a.

[0078] Of course, in embodiments where the magnet is configured with only one magnetization direction, there may be two magnets 21, spaced apart along the front-rear direction of the housing, with their magnetic poles opposite to each other to form a magnetic gap 20a. One long axis segment 40a of the flat voice coil 40 is located within the magnetic gap 20a, and the other long axis segment 40a is located outside the magnetic gap 20a. Alternatively, in some embodiments, only one magnet may be provided in the front-rear direction of the housing, and the back cover 13 may be made of a magnetically conductive material. In this way, the back cover 13 can cooperate with the magnet 21 to enhance the magnetic field strength within the magnetic gap 20a, thereby improving the acoustic effect produced by the flat voice coil 40. In other embodiments, the back cover 13 may be made of a non-magnetically conductive material.

[0079] Please refer to Figure 6 In an embodiment where the magnets are configured as a Helbeck array, two magnets 21 are respectively disposed at opposite ends of the front cover 11 along a first direction. The first magnetic block 21a is disposed near the center of the diaphragm 31, and the magnetization directions of the two opposing first magnetic blocks 21a are the same. Thus, the two magnets 21 do not need to be distinguished in terms of installation position; that is, after confirming the orientation of the magnets 21, they can be arbitrarily installed on the left or right side of the diaphragm 31, thereby improving assembly efficiency on the production line. Of course, in other embodiments, the magnetization directions of the two first magnetic blocks 21a can be opposite.

[0080] Please refer to Figure 5 and 13In one embodiment, the diaphragm 31 includes a planar portion 311 and a folded ring portion 312 disposed on the outer periphery of the planar portion 311. A membrane through-hole 31a is provided in the middle of the planar portion 311, and the periphery of the piezoelectric sheet 32 ​​is connected to the edge of the membrane through-hole 31a. Thus, the piezoelectric sheet 32 ​​can reinforce the diaphragm 31. Specifically, in this embodiment of the invention, the piezoelectric sheet 32 ​​can be a piezoelectric single crystal, a piezoelectric polycrystalline material, or a piezoelectric ceramic sheet.

[0081] Please refer to Figure 4 , 5 In one embodiment, as described in points 7 and 8, the vibration system further includes a deformable commutator 60. The flat voice coil 40 drives the vibrating sound-generating assembly 30 to vibrate via the commutator 60. The commutator 60 has a first mounting portion 60a and a second mounting portion 60b that are movably connected. The first mounting portion 60a is connected to the flat voice coil 40, and the second mounting portion 60b is connected to the vibrating sound-generating assembly 30. When the first mounting portion 60a is driven by the flat voice coil 40 to vibrate along a first direction, the second mounting portion 60b can drive the vibrating sound-generating assembly to vibrate along a second direction, which is orthogonal to the first direction. Thus, since the flat voice coil 40 vibrates along its width direction, the direction of vibration is transmitted and changed by the commutator 60, so that the vibration direction of the flat voice coil 40 can be parallel to the width direction of the diaphragm 31. This reduces the size of the electroacoustic conversion device in the thickness direction and facilitates a thinner design. Of course, in other embodiments, the flat voice coil 40 may be directly disposed on the inner side of the vibrating sound-generating component 30, and the vibration direction of the flat voice coil 40 may be perpendicular to the width direction of the diaphragm 31, that is, the flat voice coil 40 and the vibration may vibrate in the same direction.

[0082] Please refer to Figure 4 , 6 In one embodiment, up to 8, two flat voice coils 40 are provided, and two corresponding first mounting portions 60a are provided. The two flat voice coils 40 are respectively disposed at opposite ends of the commutator bracket 60 and have opposite vibration directions. The second mounting portion 60b is located between the two first mounting portions 60a. In this way, both sides of the diaphragm 31 are simultaneously driven by two flat voice coils 40, which can increase the amplitude of the vibration response, thereby improving the response sensitivity and sound pressure level of the moving coil sound-generating structure. Of course, in other embodiments, only one flat voice coil 40 may be provided.

[0083] Please refer to Figure 5 , 14In one embodiment, as shown in 17, there are two second mounting portions 60b, positioned between the two first mounting portions. One second mounting portion 60b is connected to one vibrating sound-generating component, and the other second mounting portion 60b is connected to another vibrating sound-generating component. Thus, driving two vibrating sound-generating components 30 through the same commutator 60 not only simplifies the structure of the commutator 60 but also ensures that the commutator 60 receives support from both vibrating sound-generating components 30, preventing the flat voice coil 40 from wobbling along the second direction within the magnetic gap 20a, thereby ensuring stable operation of the flat voice coil 40 within the magnetic gap 20a. Of course, in other embodiments, there may be two commutator supports, with the second mounting portions of the two commutator supports respectively connected to two diaphragms.

[0084] Please refer to Figure 5 , 14 In one embodiment, the vibration system further includes a flexible connector 66, through which the two first mounting portions 60a and the two second mounting portions 60b are movably connected. The flexible connector 66 forms a bent portion 661 between the two first mounting portions 60a and the two second mounting portions 60b. The material and structural characteristics of the flexible connector 66 are used to improve the fatigue strength of the bent portion 661, thereby increasing the service life of the commutator support 60. Of course, in other embodiments, the commutator support can also be configured as a thin, plate-like elastic metal sheet, that is, the two first mounting portions and the two second mounting portions are integrally formed, and an elastic bent portion is formed at the bent portion.

[0085] In one embodiment, the flexible connector 66 is injection molded to the first mounting portion 60a and the second mounting portion 60b. This mature and stable molding process ensures a stable and reliable connection strength between adjacent plates. Specifically, please refer to... Figure 13 and 16 Optionally, in this embodiment, the first mounting portion 60a is located on the outer side of the flexible connector 66, meaning the flexible connector 66 does not completely cover the side edge of the commutator bracket 60. This reduces the manufacturing cost and weight of the commutator bracket 60. Of course, in some embodiments, the flexible connector 66 can be hot-pressed to the first mounting portion 60a and the second mounting portion 60b. In other embodiments, the flexible connector 66 is bonded to the surface of the plate after molding. In still other embodiments, the flexible connector 66 completely covers the surface of the commutator bracket 60.

[0086] Please refer to Figure 16 and 17In one embodiment, the edges of both the first mounting portion 60a and the second mounting portion 60b are provided with a plurality of filling holes 60c for the flexible connector 66 to fill. This enhances the connection strength between the plate and the flexible connector 66, thereby increasing the service life of the commutator bracket 60. Of course, in other embodiments, the filling holes 60c may not be provided.

[0087] In one embodiment, the first mounting part 60a and the second mounting part 60b are made of metal, plastic or ceramic, such as copper, steel or aluminum alloy, and the flexible connector 66 is made of rubber, silicone or elastic PVC (polyvinyl chloride).

[0088] Please refer to Figures 14 to 17 In one embodiment, the commutator 60 includes multiple plates and multiple bends 661. The plates are spaced apart along a first direction, and adjacent plates are connected by bends 661. The plates include a first plate 61, a second plate 62, a third plate 63, a fourth plate 64, and a fifth plate 65 arranged sequentially along the first direction. Two first mounting portions 60a are respectively disposed on the first plate 61 and the fifth plate 65, and two second mounting portions 60b are both disposed on the third plate 63. This design is simple and stable, and can promptly transmit the vibration of the flat voice coil 40 to the vibrating sound-generating assembly 30. In other embodiments, the commutator 60 can also be configured as a rigid support, with its middle portion rotatably connected to the housing, one end disposed on the flat voice coil 40, and the other end disposed on the vibrating sound-generating assembly 30.

[0089] Please refer to Figures 14 to 17 In one embodiment, the commutator 60 is provided with at least one partition hole 60d, which extends along a first direction and extends at least from the second plate portion 62 to the fourth plate portion 64. The partition hole 60d divides the third plate portion 63 into at least two third sub-plate segments 631. One third sub-plate segment 631 forms a second mounting portion 60b and is connected to a vibration sound-generating assembly 30, and the other third sub-plate segment 631 forms another second mounting portion 60b and is connected to another vibration sound-generating assembly 30. Of course, in other embodiments, the partition hole may not be provided, and two vibration brackets may be provided, with the two vibration brackets respectively connected to two diaphragms.

[0090] Please refer to Figures 14 to 17In one embodiment, two partition holes 60d are provided, and the two partition holes 60d are spaced apart along the extension direction of the bent portion 661. The two partition holes 60d divide the third plate portion 63 into three third sub-plate segments 631. The middle third sub-plate segment 63 forms a second mounting portion 60b and is connected to a vibration sound-generating component 30. The other two third sub-plate segments 631 together form another second mounting portion 60b and are connected to another vibration sound-generating component 30. In this way, the forces on the two sets of vibration sound-generating components 30 can be more balanced, thereby improving their sound generation effect and sound generation stability. Specifically, in this embodiment, the third sub-plate segments 631 are optionally provided on the inner surface of the piezoelectric sheet 32. Of course, in some embodiments, the third sub-plate segments 631 may also be provided on the inner surface of the diaphragm 31. In other embodiments, only one partition hole 60d may be provided. In some other embodiments, four partition holes 60d are provided, dividing the third plate portion 63 into five third sub-plate segments 631. The first, third, and fifth third sub-plate segments 631 are arranged in sequence on one vibration sound-generating component 30, and the second and fourth third sub-plate segments 631 are arranged on another vibration sound-generating component 30.

[0091] Please refer to Figures 14 to 17 In one embodiment, the partition holes 60d extend from the first plate portion 61 to the fifth plate portion 65 and are provided at intervals. The second plate portion 62 is divided into three second sub-plate segments 621 by the two partition holes 60d. The three second sub-plate segments 621 are distributed at intervals along the extension direction of the bending portion 661. The second sub-plate segments 621 on both sides extend obliquely toward a vibrating sound-generating component 30, and the second sub-plate segment 621 in the middle extends obliquely toward another vibrating sound-generating component 30. The fourth plate portion 64 is divided into three fourth sub-plate segments 641 by the partition holes 60d. The three fourth sub-plate segments 641 are distributed at intervals along the extension direction of the bending portion 661. The fourth sub-plate segments 641 on both sides extend obliquely toward a vibrating sound-generating component 30, and the fourth sub-plate segment 641 in the middle extends obliquely toward another vibrating sound-generating component 30. The fourth sub-plate segments 641 and the opposite second sub-plate segments 621 are provided to extend obliquely in the same direction. That is, the two transmission paths for transmitting vibration from the flat voice coil to the two sets of vibrating sound-generating components are approximately the same, thereby making the sound production effects of the two sets of vibrating sound-generating components approximately equivalent. Of course, in some embodiments, the dividing hole may extend from the first plate to the fifth plate and only one such hole may be provided. One dividing hole divides the second plate into two second sub-plate segments and the fourth plate into two fourth sub-plate segments. The two sets of second and fourth sub-plate segments arranged opposite each other extend inclined toward one vibrating sound-generating component, and the other set of second and fourth sub-plate segments arranged opposite each other extend inclined toward the other vibrating sound-generating component.

[0092] Please refer to Figures 18 to 20In another embodiment of the reversing bracket 60, a sixth plate portion 67 is provided between a second mounting portion 60b and a second plate portion 62. The second plate portion 62 has a first clearance portion 622 corresponding to the sixth plate portion 67. The second plate portion 62, the sixth plate portion 67, and the second mounting portion 60b are movably connected by a flexible connector 66. A seventh plate portion 68 is also provided between the second mounting portion 60b and the fourth plate portion. The fourth plate portion 64 has a second clearance portion 642 corresponding to the seventh plate portion 68. The fourth plate portion 64, the seventh plate portion 68, and the second mounting portion 60b are connected by a flexible connector 66. Specifically, optionally, the partition hole 60d extends from the second plate portion 62 to the fourth plate portion 64. The second plate portion 62 extends obliquely toward the direction of approaching another vibrating sound-generating component 30, the sixth plate portion 67 extends obliquely toward the direction of approaching a vibrating sound-generating component 30, the fourth plate portion extends obliquely toward the direction of approaching another vibrating sound-generating component 30, and the seventh plate portion 68 extends obliquely toward the direction of approaching a vibrating sound-generating component 30.

[0093] Please refer to Figure 5 , 7 In one embodiment, the vibration system further includes two connecting rods 70. Two flat voice coils 40 are respectively connected to two first mounting portions 60a via the connecting rods 70. Each connecting rod 70 includes a main rod section 71 and auxiliary rod sections 72 located at both ends of the main rod section 71. The two ends of the flat voice coil 40 are respectively located on the auxiliary rod sections 72, which are situated outside the magnetic gap 20a. The main rod section 71 is located on the first mounting portion 60a. Thus, while ensuring the connection strength between the commutator bracket 60 and the flat voice coil 40, it avoids the problem of partial intrusion of the commutator bracket 60 or connecting rods 70 into the magnetic gap 20a, thereby reducing the height of the flat voice coil 40. In other words, by placing the auxiliary rod sections 72 outside the magnetic gap 20a, the height of the flat voice coil 40 can be maximized, thereby improving its response within the magnetic field. Of course, in some embodiments, one end of the auxiliary rod section 72 may be located within the magnetic gap 20a. In some other embodiments, the connecting rod 70 may be omitted, and the commutation bracket 60 may be directly fixedly connected to the flat voice coil 40.

[0094] Please refer to Figure 7 and 8In one embodiment, the vibration system further includes at least two centering springs 80 disposed on the housing 10. The elastic action directions of the at least two centering springs 80 are arranged facing each other and are respectively connected to the two connecting rods 70. In this way, the centering springs 80 can limit the reversing bracket 60, so that the second mounting part 60b on the reversing bracket 60 can vibrate along the design direction and avoid swaying perpendicular to the vibration direction, thereby improving the operational stability of the reversing bracket 60. Specifically, in this embodiment, optionally, four centering springs 80 are provided, and the four centering springs 80 are respectively disposed on the four secondary rod segments 72 of the two connecting rods 70, so as to achieve a better centering and limiting effect. Of course, in some embodiments, only two centering springs 80 can be provided, and both centering springs 80 are disposed on the same side of the two connecting rods 70; or the two centering springs 80 are disposed on different sides of the two connecting rods 70, that is, the two centering springs 80 are approximately disposed on a diagonal line of the reversing bracket 60. In some other embodiments, the centering spring 80 may not be provided.

[0095] Please refer to Figure 21 In one embodiment, the centering spring has a roughly U-shaped structure, specifically including a bending section 81, two mounting sections 83 located at both ends of the bending section 81, and two connecting sections 82. The opening of the bending section 81 faces away from the commutator support. The mounting sections 83 are connected to the bending section 81 through the connecting sections 82. The mounting sections 83 are formed by folding the side edge of the connecting sections 82 outward along the surface of the piezoelectric sheet. One mounting section 83 is close to the commutator support and connected to the connecting rod, while the other mounting section 83 is away from the commutator support and connected to the housing. Thus, the four centering springs have a simple structure and can work together to provide good limiting for the commutator support, thereby improving the operational stability of the commutator support. Specifically, in this embodiment, the centering spring may optionally be made of a material with certain rigidity and resilience, such as metals like aluminum alloy, stainless steel, copper alloy, and manganese steel, or plastics like polyethylene naphthalate (PEN), polyimide (PI), polyethylene terephthalate (PET), and polyetheretherketone (PEEK). Of course, in some embodiments, the centering spring may also have a roughly S-shaped or W-shaped structure.

[0096] The above description is merely an optional embodiment of the present invention and does not limit the patent scope of the present invention. All equivalent structural transformations made using the contents of the present invention's specification and drawings under the inventive concept of the present invention, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present invention.

Claims

1. An electroacoustic conversion device, characterized in that, include: case; A magnetic circuit system is provided in the housing and has a magnetic gap; A vibration system is provided in the housing. The vibration system includes two vibration sound generating components and a voice coil. The two vibration sound generating components are respectively disposed on opposite sides of the housing. Each vibration sound generating component includes a diaphragm and a piezoelectric sheet disposed on the diaphragm. The voice coil is disposed in the magnetic gap and drives the vibration sound generating component to vibrate. as well as A first conductive line and a second conductive line, wherein the first conductive line is electrically connected to the voice coil and the second conductive line is electrically connected to the piezoelectric element; The housing is provided with a first conductive terminal, and the second conductive line is provided on the inner or outer surface of the diaphragm and electrically connected to the first conductive terminal and the piezoelectric sheet; the first conductive terminal is connected to an external circuit. The diaphragm includes a planar portion, a folded ring portion disposed on the outer periphery of the planar portion, and a fixing portion disposed on the outer periphery of the folded ring portion. A membrane through-hole is provided in the middle of the planar portion. The periphery of the piezoelectric sheet is connected to the edge of the membrane through-hole. The fixing portion is connected to the housing. The second conductive line is arranged at least on the folded ring portion and the fixing portion. The second conductive line is electroplated, coated, or embedded on the diaphragm. Alternatively, the second conductive line is etched from a flexible circuit board composited on the diaphragm. The second conductive line has a second conductive protrusion protruding towards the first conductive terminal. The housing has an adhesive storage groove. One end of the first conductive terminal is located in the adhesive storage groove. The adhesive storage groove is filled with a second conductive adhesive. The second conductive adhesive fixes the second conductive line and the first conductive terminal.

2. The electroacoustic conversion device as described in claim 1, characterized in that, The second conductive line is fixedly connected to the piezoelectric sheet by the first conductive adhesive.

3. The electroacoustic conversion device as described in claim 1, characterized in that, The first conductive terminal has a first conductive protrusion protruding towards the second conductive line.

4. The electroacoustic conversion device as described in claim 1, characterized in that, The housing includes a front cover, a middle frame, and a rear cover connected to each other. The front cover and the rear cover are opposite to each other and have a through hole. Two diaphragms are fixed to the front cover and the rear cover respectively. The fixing part is connected to the edge of the through hole. The first conductive terminal is disposed on the middle frame.

5. The electroacoustic conversion device as described in claim 4, characterized in that, The middle frame is also provided with a second conductive terminal, and the voice coil is electrically connected to the second conductive terminal.

6. The electroacoustic conversion device as described in claim 4, characterized in that, The magnetic circuit system includes a magnet disposed on the front cover, the magnet and the rear cover being spaced apart along the vibration direction of the diaphragm, and the magnetic gap being formed on the side of the magnet near the rear cover.

7. The electroacoustic conversion device as described in claim 4, characterized in that, The back cover is made of either a magnetic or non-magnetic material.

8. The electroacoustic conversion device as described in claim 6, characterized in that, The voice coil is configured as a flat voice coil. The magnet includes two magnets, which are respectively disposed at opposite ends of the front cover along a first direction. Each magnet is configured as a Helbeck array structure. Each magnet includes a first magnetic block, a second magnetic block, and a third magnetic block distributed sequentially along the first direction. The magnetization direction of the first magnetic block is set along the vibration direction of the diaphragm and is set opposite to the magnetization direction of the third magnetic block. The magnetization direction of the second magnetic block is set from the third magnetic block toward the first magnetic block.

9. The electroacoustic conversion device according to any one of claims 1 to 8, characterized in that, The voice coil is configured as a flat voice coil, and the vibration system further includes a deformable commutator bracket. The flat voice coil drives the vibration sound-generating component to vibrate through the commutator bracket. The commutator bracket has a first mounting part and a second mounting part that are movably connected. The first mounting part is connected to the flat voice coil, and the second mounting part is connected to the vibration sound-generating component. When the first mounting part is driven by the flat voice coil to vibrate along a first direction, the second mounting part can drive the vibration sound-generating component to vibrate along a second direction, which is orthogonal to the first direction.

10. The electroacoustic conversion device as described in claim 9, characterized in that, There are two first mounting parts and two second mounting parts, with two second mounting parts disposed between the two first mounting parts. One second mounting part is connected to one of the vibration sound-generating components, and the other second mounting part is connected to another vibration sound-generating component.

11. The electroacoustic conversion device as claimed in claim 10, characterized in that, The vibration system further includes a flexible connector, through which the two first mounting portions and the two second mounting portions are movably connected, and the flexible connector forms a bent portion between the two first mounting portions and the two second mounting portions.

12. The electroacoustic conversion device as claimed in claim 11, characterized in that, The flexible connector is hot-pressed to the surfaces of the first mounting portion and the second mounting portion, or the flexible connector is injection molded to the first mounting portion and the second mounting portion.

13. The electroacoustic conversion device as described in claim 12, characterized in that, Both the first mounting portion and the second mounting portion have multiple filling holes on their edges, which are used for filling by the flexible connector; and / or The first mounting part and the second mounting part are made of metal or plastic; and / or The flexible connector is made of rubber or silicone.

14. The electroacoustic conversion device as described in claim 10, characterized in that, Two flat voice coils are provided, which are respectively connected to the two first mounting parts. The two flat voice coils are respectively located at opposite ends of the commutation bracket and have opposite vibration directions.

15. The electroacoustic conversion device as described in claim 14, characterized in that, The reversing bracket includes multiple plate sections and multiple bending sections. The multiple plate sections are spaced apart along the first direction, and adjacent plate sections are connected by the bending sections. The multiple plate sections include a first plate section, a second plate section, a third plate section, a fourth plate section, and a fifth plate section arranged sequentially along the first direction. Two first mounting sections are respectively disposed on the first plate section and the fifth plate section, and two second mounting sections are both disposed on the third plate section.

16. The electroacoustic conversion device as claimed in claim 15, characterized in that, The reversing bracket is provided with at least one partition hole, which extends along the first direction and extends at least from the second plate portion to the fourth plate portion. The at least one partition hole divides the third plate portion into at least two third sub-plate segments. One third sub-plate segment forms a second mounting portion, and the other third sub-plate segment forms another second mounting portion.

17. The electroacoustic conversion device as claimed in claim 16, characterized in that, The partition hole is provided in two places, and the two partition holes are distributed at intervals along the extension direction of the bending part. The two partition holes divide the third plate into three third sub-plate segments. The third sub-plate segment located in the middle forms a second mounting part, and the other two third sub-plate segments together form another second mounting part.

18. The electroacoustic conversion device as claimed in claim 9, characterized in that, The second mounting portion is located on the inner side of the piezoelectric sheet.

19. The electroacoustic conversion device as claimed in claim 14, characterized in that, The vibration system further includes two connecting rods, and the two flat voice coils are respectively connected to the two first mounting parts through the two connecting rods. The connecting rod includes a main rod section and auxiliary rod sections disposed at both ends of the main rod section. The two ends of the flat voice coil are respectively disposed at one of the auxiliary rod sections, and the main rod section is disposed at the first mounting part.

20. The electroacoustic conversion device as claimed in claim 19, characterized in that, The vibration system further includes at least two centering springs disposed on the housing, the elastic action directions of the at least two centering springs being arranged in opposite directions, and respectively connected to the two connecting rods.

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