WO2021237794A1 - Dispositif de production de son - Google Patents

Dispositif de production de son Download PDF

Info

Publication number
WO2021237794A1
WO2021237794A1 PCT/CN2020/094709 CN2020094709W WO2021237794A1 WO 2021237794 A1 WO2021237794 A1 WO 2021237794A1 CN 2020094709 W CN2020094709 W CN 2020094709W WO 2021237794 A1 WO2021237794 A1 WO 2021237794A1
Authority
WO
WIPO (PCT)
Prior art keywords
diaphragm
frame
voice coil
arm
magnetic
Prior art date
Application number
PCT/CN2020/094709
Other languages
English (en)
Chinese (zh)
Inventor
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 (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 瑞声声学科技(深圳)有限公司, 瑞声科技(新加坡)有限公司 filed Critical 瑞声声学科技(深圳)有限公司
Publication of WO2021237794A1 publication Critical patent/WO2021237794A1/fr

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
    • H04R9/00—Transducers of moving-coil, moving-strip, or moving-wire type
    • H04R9/02—Details
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
    • H04R9/00—Transducers of moving-coil, moving-strip, or moving-wire type
    • H04R9/02—Details
    • H04R9/04—Construction, mounting, or centering of coil
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
    • H04R9/00—Transducers of moving-coil, moving-strip, or moving-wire type
    • H04R9/06—Loudspeakers

Definitions

  • the utility model relates to the field of electro-acoustic conversion, in particular to a sound-producing device applied to electronic sound box products.
  • the sound generating device is used in the mobile terminal to realize the conversion of audio signals into sound for playback.
  • the related art sound device includes a basin frame, a vibration system fixed to the basin frame, and a magnetic circuit system with a magnetic gap.
  • the magnetic circuit system drives the vibration system to vibrate and produce sound.
  • the vibration system includes The frame is used for vibrating and sounding the diaphragm, the voice coil, the elastic support component and the frame, one end of the frame is connected to the diaphragm, the other end is connected to the voice coil and the voice coil is suspended in the magnetic gap; the elastic support An assembly connects the skeleton to the basin frame to provide lateral support to prevent swinging.
  • the skeleton is formed by metal stamping and integral molding.
  • metal stamping and integral molding For example, aluminum alloy material is usually used for stamping and forming.
  • the skeleton is used as a supporting structure to connect the diaphragm and the voice coil.
  • the flatness of the bonding with the skeleton is poor, and the rounded corners are relatively large, which makes the connection strength of the diaphragm and the skeleton poor, which affects the reliability and acoustic performance of the sound device.
  • the purpose of the utility model is to provide a sound device with good reliability and excellent acoustic performance.
  • the present invention provides a sound generating device, which includes a basin frame, a vibration system supported on the basin frame, and a magnetic circuit system that drives the vibration system to vibrate and produce sound, the magnetic circuit system having a magnetic gap ,
  • the vibration system includes:
  • a diaphragm, the diaphragm is fixed to the basin frame;
  • a voice coil the voice coil is inserted in the magnetic gap to drive the diaphragm to vibrate and produce sound;
  • a frame assembly includes a metal frame and a first plastic connection part, the first plastic connection part is fixedly connected to an end of the metal frame close to the diaphragm;
  • the metal frame includes a frame body in a ring shape And at least two skeleton supporting parts bent inwardly from the skeleton body to the magnetic gap;
  • the first plastic connecting part is located between the skeleton body and the diaphragm, and connects the skeleton body Connected to the diaphragm, the frame support part is connected to the voice coil and suspends the voice coil in the magnetic gap.
  • the frame support portion is connected to an end of the voice coil away from the diaphragm.
  • the vibration system further includes an elastic support assembly fixed to the basin frame and opposed to the diaphragm at intervals, and the frame assembly further includes a second end connected to the metal frame away from the diaphragm.
  • Two plastic connecting parts the second plastic connecting part is made of plastic material, and the second plastic connecting part is connected with the elastic support component.
  • the metal frame further includes a first reinforcement part bent and extended outward from an end of the frame body close to the diaphragm, and a first reinforcement part bent and extended inward from an end of the frame body away from the diaphragm.
  • a second reinforcement part, the first reinforcement part is at least partially embedded in the first plastic connecting part, and the second reinforcement part is at least partially embedded in the second plastic connecting part.
  • the metal frame is respectively integrated with the first plastic connecting portion and the second plastic connecting portion by injection molding.
  • the second reinforcing portion is provided with a plurality of reinforcing holes penetrating therethrough, and the second plastic connecting portion is partially filled in the reinforcing holes.
  • the frame support portion includes a receiving shell with a receiving space extending from the second reinforcing portion in the direction of the voice coil, and a support arm protruding and extending from a side of the receiving shell close to the voice coil ,
  • the voice coil is supported by the support arm;
  • the elastic support assembly includes an elastic member, the elastic member includes a first arm fixed to the basin frame, a second fixed connection with the second plastic connecting part An arm, an elastic arm connecting the first arm and the second arm, and a third arm extending from the second arm in the direction of the voice coil, and the third arm is accommodated in the accommodating space.
  • the elastic member is a flexible circuit board
  • the same frame supporting portion includes the supporting arms arranged in pairs, and the supporting arms arranged in a pair are arranged at intervals to form a connection with the accommodating space.
  • a slot, the lead of the voice coil extends into the accommodating space through the relief slot and is electrically connected with the third arm.
  • the elastic support assembly further includes an auxiliary diaphragm located on a side of the elastic member away from the diaphragm, one side of the auxiliary diaphragm is fixed to the first arm, and the other side is fixed to the The second arm.
  • the magnetic circuit system includes a magnetic yoke fixed to the basin frame, a main magnetic steel unit and a secondary magnetic steel unit respectively fixed to the magnetic yoke, and a cover and abutting support on the main magnetic steel unit.
  • the secondary magnetic steel unit is arranged at intervals around the main magnetic steel unit to form the magnetic gap, and the secondary magnetic steel unit is provided with a waypoint through it, so The frame support portion extends into the magnetic gap through the relief opening.
  • the diaphragm includes a first fixing part that is ring-shaped and fixed to the secondary magnetic steel unit, a second fixing part that is ring-shaped and fixed to the basin frame, located at the first fixing part and Between the second fixed portions and the ring-shaped first folding ring portion, the second folding ring portion surrounding the first folding ring portion and spaced apart from each other, and located between the first folding ring portion and the second folding ring portion
  • the ring-shaped vibrating part between the ring portions the inner side of the vibrating portion is connected to the first ring portion, the outer side of the vibrating portion is connected to the second ring portion, and the first ring portion
  • the side of the ring portion away from the second folding ring portion is connected to the first fixing portion, and the side of the second folding ring portion away from the first folding ring portion is connected to the second fixing portion;
  • the magnetic bowl passes through the first fixing portion and is exposed to the diaphragm, and is pressed on a side of the first fixing portion away from the auxiliary magnetic steel unit to form a sealed fixing.
  • the first plastic connecting portion Connected to the vibrating part.
  • the frame assembly includes a metal frame and a first plastic connecting part, and the first plastic connecting part is fixedly connected to an end of the metal frame close to the diaphragm;
  • the first plastic connecting portion is located between the frame body and the diaphragm, and connects the metal frame to the diaphragm, and is connected to the voice coil through the frame support portion of the metal frame.
  • the voice coil is suspended in the magnetic gap; because the metal frame and the diaphragm form a fixed connection through the first plastic connection part, and the first plastic connection part is made of plastic material, which has strong plasticity, it can effectively ensure
  • the flatness of the connecting surface between the diaphragm and the first plastic connecting part increases the connection reliability, and the first plastic connecting part of plastic material acts as a part of the metal frame of the metal material, which can also effectively reduce the overall quality of the frame assembly, thereby
  • the vibration effect is increased, and the acoustic performance of the sound-producing device is further improved; in addition, in the sound-producing device of the present invention, a second plastic connecting part made of plastic material is arranged in the same way, and the metal skeleton is connected to the second plastic connecting part through the second plastic connecting part.
  • the connection of the elastic support components also further improves the acoustic performance of the sound emitting device.
  • Figure 1 is a schematic diagram of the three-dimensional structure of the sound generating device of the present invention.
  • Figure 2 is an exploded view of part of the three-dimensional structure of the sound device of the present invention.
  • Figure 3 is a sectional view taken along the line A-A in Figure 1;
  • Fig. 4 is an enlarged view of part B shown in Fig. 3;
  • Figure 5 is an exploded schematic diagram of part of the structure of the skeleton assembly of the sound device of the present invention.
  • Fig. 6 is a schematic diagram of the structure of assembling the skeleton assembly and the elastic part of the sound device of the present invention.
  • the present invention provides a sound generating device 100, which includes a basin frame 1, a vibration system 2 and a magnetic circuit system 3 with a magnetic gap 30.
  • the vibration system 2 and the magnetic circuit system 3 are respectively supported on the basin frame 1, and the magnetic circuit system 3 drives the vibration system 2 to vibrate and produce sound.
  • the vibration system 2 includes: a diaphragm 21, a skeleton component 22, a voice coil 23 and an elastic support component 24.
  • the diaphragm 21 is fixed to the basin frame 1 for vibrating and sounding.
  • the voice coil 23 is inserted into the magnetic gap 30 to drive the diaphragm 21 to vibrate and produce sound.
  • the frame assembly 22 includes a metal frame 221 and a first plastic connecting portion 222, for example, the metal frame 221 is made of aluminum alloy material.
  • the first plastic connecting portion 222 is fixedly connected to an end of the metal frame 221 close to the diaphragm 21. Because the first plastic connecting portion 222 is made of plastic material and has strong plasticity, it can effectively ensure the flatness of the connecting surface of the diaphragm 21 and the first plastic connecting portion 222, increase the connection reliability, and the plastic material has a high degree of plasticity.
  • a plastic connecting portion 222 serves as a part of the metal skeleton 221 of metal material, which can also effectively reduce the overall mass of the skeleton assembly, thereby increasing the vibration effect and further improving the acoustic performance of the sound generating device 100. In addition, when the first plastic connecting portion 222 is made of plastic material, it is easier to form rounded corners, which reduces the difficulty of forming.
  • the metal frame 221 includes a ring-shaped frame body 2211 and at least two frame support portions 2212 bent inwardly from the frame body 2211 to the magnetic gap 30.
  • the first plastic connecting portion 222 is located between the frame body 2211 and the diaphragm 21, and connects the frame body 2211 to the diaphragm 21, and the frame support portion 2212 and the voice coil 23 The voice coil 23 is connected and suspended in the magnetic gap 30.
  • the frame supporting portion 2212 is connected to an end of the voice coil 23 away from the diaphragm 21. This structure can relieve the space limitation between the voice coil 23 and the diaphragm 21 and make more use of the freedom of structural design.
  • the frame supporting portion 2212 includes at least two to better realize the support balance for the voice coil 23, and it is more preferable that the two frame supporting portions 2212 are arranged directly opposite to each other, thereby improving the vibration stability.
  • the frame supporting portion 2212 includes a housing shell 22121 with a housing space 20 extending from the frame body 2211 in the direction of the voice coil 23, and a housing shell 22121 close to the voice coil.
  • a supporting arm 22122 protrudes from one side of 23, and the voice coil 23 is supported by the supporting arm 22122.
  • the vibration system 2 further includes the elastic support assembly 24 fixed to the basin frame 1 and opposite to the diaphragm 21 and arranged at intervals, and the elastic support assembly 24 is connected to the metal frame 221.
  • the frame assembly 22 further includes a second end connected to the metal frame 221 away from the diaphragm 21.
  • the second plastic connecting portion 223 is made of plastic material, and the second plastic connecting portion 223 is connected to the elastic support assembly 24.
  • the metal frame 221 is connected to the elastic support assembly 24 through the second plastic connecting portion 223, which also further improves the acoustic performance of the sound emitting device 100.
  • the metal frame 221 further includes a first reinforcing portion 2213 bent and extended outward from an end of the frame body 2211 close to the diaphragm 21, and an end of the frame body 2211 away from the diaphragm 21
  • the second reinforcing portion 2214 is bent and extended inwardly, and the receiving shell 22121 is formed by extending the second reinforcing portion 2214 in the direction of the voice coil 23.
  • the first reinforcing portion 2213 is at least partially embedded in the first plastic connecting portion 222
  • the second reinforcing portion 2214 is at least partially embedded in the second plastic connecting portion 223.
  • the metal frame 221 is injection-molded integrally with the first plastic connecting portion 222 and the second plastic connecting portion 223 respectively, which reduces the number of workpieces and improves assembly efficiency.
  • the second reinforcement portion 2214 is provided There are a plurality of reinforcing holes 2215 penetrating therethrough. When the second plastic connecting portion 223 wraps and connects the second reinforcing portion 2214, part of the reinforcing hole 2215 is filled in the reinforcing hole 2215 to form a position-limiting and reinforcing effect.
  • the elastic support assembly 24 includes an elastic member 241, and the elastic member 241 includes a first arm 2411 fixed to the basin frame 1, a second arm 2412 fixedly connected to the second plastic connecting portion 223, and connected to the The elastic arm 2413 of the first arm 2411 and the second arm 2412.
  • the first arm 2411, the second arm 2412, and the elastic arm 2413 jointly support the metal frame 221, and the voice coil 23 is supported by the metal frame 221, which effectively improves the vibration performance of the diaphragm 21 on the one hand. On the other hand, it prevents the voice coil 23 from swinging laterally during the vibration process, and improves the stability.
  • the elastic member 241 is set as a flexible circuit board, which not only realizes the above-mentioned functions of the elastic member 241, but also can be used to electrically connect with the voice coil 23 to introduce external electrical signals to the voice coil 23 to prevent the voice coil 23
  • the risk of wire breakage due to too long leads improves reliability.
  • the elastic member 241 further includes a third arm 2414 extending from the second arm 2412 in the direction of the voice coil 23, and the third arm 2414 is accommodated in a housing shell of the frame support part 2212 22121 in the receiving space 20.
  • the same frame support portion 2212 includes the support arms 22122 arranged in pairs, and the support arms 22122 arranged in pairs are arranged at intervals to form a relief groove 201 communicating with the receiving space 20, and the voice coil
  • the lead 231 of 23 extends into the receiving space 20 through the relief groove 201 and is electrically connected to the third arm 2414.
  • the elastic support assembly 24 also includes an auxiliary diaphragm 242 located on the side of the elastic member 241 away from the diaphragm 21.
  • One side of the auxiliary diaphragm 241 is fixed to the first arm 2411, and the other side is fixed. On the second arm 2412.
  • the auxiliary diaphragm 241 further improves the vibration performance and vibration stability of the diaphragm 21.
  • the magnetic circuit system 3 in order to increase the volume of the magnetic circuit system 3 and increase the driving force, is arranged in a structure exposed to the diaphragm 21.
  • the magnetic circuit system 3 includes a magnetic yoke 31 fixed to the basin frame 1, a main magnetic steel unit 32 and a secondary magnetic steel unit 33 fixed to the magnetic yoke 31, and a cover provided on the main magnetic
  • the steel unit 32 abuts and supports the magnetic bowl 34 of the secondary magnetic steel unit 33.
  • the auxiliary magnetic steel unit 33 is arranged around the main magnetic steel unit 32 at intervals and forms the magnetic gap 30.
  • the auxiliary magnetic steel unit 33 is provided with a relief opening 331 penetrating therethrough, and the skeleton support portion 2212 is passed through The relief opening 331 extends into the magnetic gap 30.
  • the diaphragm 21 includes a first fixing portion 211 that is ring-shaped and fixed to the auxiliary magnetic steel unit 33, a second fixing portion 212 that is ring-shaped and fixed to the basin frame 1, and is located at the first fixed portion 211.
  • a first folding ring portion 213 formed between the second fixing portion 211 and the second fixing portion 212 in a ring shape, a second folding ring portion 214 surrounding the first folding ring portion 213 and spaced apart from each other, and located at the first folding ring portion 213
  • the first folding ring portion 213 and the second folding ring portion 214 are used to provide elastic support and amplitude for the vibration portion 215 when it vibrates.
  • the vibrating part 215 is used to radiate sound waves to generate sound when vibrating.
  • the first plastic connecting part 222 is connected to the vibrating part 215.
  • the inner side of the vibrating part 215 is connected to the first folding ring part 213, the outer side of the vibrating part 215 is connected to the second folding ring part 214, and the first folding ring part 213 is away from the second folding ring part.
  • One side of the ring portion 214 is connected to the first fixing portion 211, and the side of the second folding ring portion 214 away from the first folding ring portion 213 is connected to the second fixing portion 212.
  • the magnetic bowl 34 passes through the first fixing portion 211 and is exposed to the diaphragm 21, and is pressed on a side of the first fixing portion 211 away from the secondary magnetic steel unit 33 to form a sealed fixing.
  • the frame assembly includes a metal frame and a first plastic connecting part, and the first plastic connecting part is fixedly connected to an end of the metal frame close to the diaphragm.
  • the first plastic connecting portion is located between the frame body and the diaphragm, and connects the metal frame to the diaphragm, and is connected to the voice coil through the frame support portion of the metal frame And the voice coil is suspended in the magnetic gap; because the metal frame and the diaphragm form a fixed connection through the first plastic connection part, and the first plastic connection part is made of plastic material, which has strong plasticity, it can effectively Ensure the flatness of the connection surface between the diaphragm and the first plastic connection part, increase connection reliability, and the first plastic connection part of plastic material acts as a part of the metal frame of the metal material, which can also effectively reduce the overall quality of the frame assembly.
  • a second plastic connecting part made of plastic material is arranged in the same way, and the metal frame is connected through the second plastic connecting part.
  • the connection with the elastic support assembly also further improves the acoustic performance of the sound emitting device.

Abstract

Le présent modèle d'utilité concerne un dispositif de production de son, comprenant un cadre, un système de vibration supporté sur le cadre, et un système de circuit magnétique ayant un entrefer magnétique. Le système de vibration comprend une membrane vibrante fixée sur le cadre ; une bobine mobile insérée dans l'entrefer magnétique et utilisée pour entraîner la membrane vibrante à vibrer et à produire du son ; et un ensemble de cadre comprenant un cadre métallique et une première partie de connexion en plastique, dans lequel la première partie de connexion en plastique est connectée de manière fixe à une extrémité du cadre métallique proche du diaphragme vibrant, le cadre métallique comprend un corps de cadre annulaire et au moins deux parties de support de cadre qui sont pliées vers l'intérieur à partir du corps de cadre et s'étendent jusqu'à l'espace magnétique, la première partie de connexion en plastique est située entre le corps de cadre et le diaphragme vibrant et connecte le corps de cadre au diaphragme vibrant, et les parties de support de cadre sont connectées à la bobine mobile et suspendent la bobine mobile dans l'espace magnétique. Par rapport à l'art apparenté, le dispositif de production sonore du présent modèle d'utilité présente une meilleure fiabilité et de meilleures performances acoustiques.
PCT/CN2020/094709 2020-05-28 2020-06-05 Dispositif de production de son WO2021237794A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CN202020945207.7 2020-05-28
CN202020945207.7U CN212628394U (zh) 2020-05-28 2020-05-28 发声器件

Publications (1)

Publication Number Publication Date
WO2021237794A1 true WO2021237794A1 (fr) 2021-12-02

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ID=74749621

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Application Number Title Priority Date Filing Date
PCT/CN2020/094709 WO2021237794A1 (fr) 2020-05-28 2020-06-05 Dispositif de production de son

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CN (1) CN212628394U (fr)
WO (1) WO2021237794A1 (fr)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114513728B (zh) * 2021-12-31 2024-03-12 歌尔股份有限公司 电子设备

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7079665B2 (en) * 2000-06-26 2006-07-18 Matsushita Electric Industrial Co., Ltd. Loudspeaker
US20100014703A1 (en) * 2008-07-18 2010-01-21 Cheng Uei Precision Industry Co., Ltd. Loudspeaker
CN203590452U (zh) * 2013-12-14 2014-05-07 惠州超声音响有限公司 一种超薄型喇叭
CN108430011A (zh) * 2018-01-27 2018-08-21 瑞声科技(新加坡)有限公司 发声器件
CN208707873U (zh) * 2018-09-21 2019-04-05 赣州圣通电子有限公司 一种具有高频补偿结构的低音喇叭
CN110996226A (zh) * 2019-11-21 2020-04-10 瑞声科技(新加坡)有限公司 发声器件
CN111065025A (zh) * 2019-11-21 2020-04-24 瑞声科技(新加坡)有限公司 发声器件

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7079665B2 (en) * 2000-06-26 2006-07-18 Matsushita Electric Industrial Co., Ltd. Loudspeaker
US20100014703A1 (en) * 2008-07-18 2010-01-21 Cheng Uei Precision Industry Co., Ltd. Loudspeaker
CN203590452U (zh) * 2013-12-14 2014-05-07 惠州超声音响有限公司 一种超薄型喇叭
CN108430011A (zh) * 2018-01-27 2018-08-21 瑞声科技(新加坡)有限公司 发声器件
CN208707873U (zh) * 2018-09-21 2019-04-05 赣州圣通电子有限公司 一种具有高频补偿结构的低音喇叭
CN110996226A (zh) * 2019-11-21 2020-04-10 瑞声科技(新加坡)有限公司 发声器件
CN111065025A (zh) * 2019-11-21 2020-04-24 瑞声科技(新加坡)有限公司 发声器件

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