CN107809708B

CN107809708B - Electroacoustic component, electroacoustic device and mobile terminal

Info

Publication number: CN107809708B
Application number: CN201711244141.8A
Authority: CN
Inventors: 吴连俊
Original assignee: Guangdong Oppo Mobile Telecommunications Corp Ltd
Current assignee: Guangdong Oppo Mobile Telecommunications Corp Ltd
Priority date: 2017-11-30
Filing date: 2017-11-30
Publication date: 2020-05-05
Anticipated expiration: 2037-11-30
Also published as: CN107809708A; WO2019105220A1

Abstract

The invention discloses an electroacoustic assembly which is fixed on a circuit board and comprises: the loudspeaker monomer comprises a bottom plate, an inner frame and a vibrating diaphragm, wherein the inner frame is fixed on the bottom plate, the bottom plate is used for fixedly connecting the circuit board, the periphery of the vibrating diaphragm is fixedly connected on the inner frame, and a sound-emitting cavity is formed between the inner frame and the vibrating diaphragm; outer frame is located the free week side of speaker, outer frame include outer roof, outer bottom plate and connect in outer roof with outer panel between the bottom plate, outer roof butt the vibrating diaphragm, outer roof the outer panel outer bottom plate reaches form the back sound chamber between the internal frame, be equipped with the leakage hole on the internal frame and be used for the intercommunication back sound chamber with the chamber of making a sound, outer bottom plate with the vertical distance of outer roof is less than the vibrating diaphragm with the vertical distance of bottom plate. The invention also discloses an electroacoustic device and a mobile terminal. The tone quality effect of the electroacoustic component is optimized.

Description

Electroacoustic component, electroacoustic device and mobile terminal

Technical Field

The invention relates to the technical field of electronic equipment, in particular to an electroacoustic component, an electroacoustic device and a mobile terminal.

Background

As the applications of mobile terminal products become more and more extensive, the functions of the mobile terminals become more and more diversified. The mobile terminal is not only a tool for conversation, but also an entertainment device for playing videos and music, so that the tone quality effect of playing music by the mobile terminal greatly influences the experience of users. The electroacoustic component is a main device for playing sound of the mobile terminal, and at present, the moving-coil electroacoustic component is the most common type of electroacoustic component applied to the mobile terminal.

In the prior art, in order to meet the light and thin design of a mobile terminal, the thickness of an electroacoustic component is small, the sound emitted by a generating source cannot be processed inside the electroacoustic component, and the tone quality of the sound emitted by the electroacoustic component is poor, so that the user experience is influenced.

Disclosure of Invention

The invention aims to provide an electroacoustic component, an electroacoustic device and a mobile terminal, and aims to solve the problems that in the prior art, the tone quality of sound emitted by the electroacoustic component is poor and user experience is influenced.

In order to solve the above technical problem, the present invention provides an electroacoustic assembly fixed on a circuit board, the electroacoustic assembly comprising:

the loudspeaker monomer comprises a bottom plate, an inner frame and a vibrating diaphragm, wherein the inner frame is fixed on the bottom plate, the bottom plate is used for fixedly connecting the circuit board, the periphery of the vibrating diaphragm is fixedly connected on the inner frame, and a sound-emitting cavity is formed between the inner frame and the vibrating diaphragm;

outer frame is located the free week side of speaker, outer frame include outer roof, outer bottom plate and connect in outer roof with outer panel between the bottom plate, outer roof butt the vibrating diaphragm, outer roof the outer panel outer bottom plate reaches form the back sound chamber between the internal frame, be equipped with the leakage hole on the internal frame and be used for the intercommunication back sound chamber with the chamber of making a sound, outer bottom plate with the vertical distance of outer roof is less than the vibrating diaphragm with the vertical distance of bottom plate.

In one embodiment, the leakage hole is located between a perpendicular projection of the outer top plate to the inner frame and the outer bottom plate.

In one embodiment, the speaker unit further includes a driving member, the driving member is accommodated in the sound-generating cavity, the driving member includes a first driving member and a second driving member, the first driving member is fixed on the bottom plate or on the inner frame, the second driving member is fixed on the vibrating diaphragm, and the second driving member is used for being opposite to the first driving member to vibrate so as to drive the vibrating diaphragm to generate sound.

In one embodiment, the first driving member is a magnet, the second driving member is a coil, the first driving member includes a first magnet and a second magnet, the first magnet is fixed on the inner frame, the second magnet is fixed on the bottom plate, the second driving member is located between the first magnet and the second magnet, the second driving member is electrically connected to a driving circuit, and the driving circuit is configured to drive the second driving member to vibrate.

In one embodiment, the leakage holes include a first leakage hole and a second leakage hole, the first leakage hole is located between the vertical projection of the first magnet on the inner frame and the diaphragm, and the second leakage hole is located between the vertical projection of the first magnet on the inner frame and the outer bottom plate.

In one embodiment, the first magnet includes a first sidewall facing the diaphragm, and an inner wall of the first leakage hole is flush with the first sidewall; the first magnet further includes a second sidewall facing the bottom plate, an inner wall of the second leakage hole being flush with the second sidewall.

In one embodiment, the electroacoustic component further comprises sound absorption particles, and the sound absorption particles are filled in the rear sound cavity.

The invention also provides an electroacoustic device, which comprises a circuit board and the electroacoustic component, wherein the bottom plate is fixedly connected with the circuit board, and the circuit board is provided with a driving circuit for driving the vibrating diaphragm to vibrate and sound.

In one embodiment, the circuit board includes a first surface, the circuit board is provided with a receiving groove recessed into the first surface, the speaker unit is at least partially received in the receiving groove, and the outer bottom plate contacts the first surface.

The invention also provides a mobile terminal comprising the electroacoustic device.

The invention has the following beneficial effects: the sound-generating cavity is communicated with the back sound cavity through the leakage hole, the energy of sound waves is consumed by friction among sound-absorbing particles in the back sound cavity, the vibration effect of gas is changed, the characteristics of the sound waves are changed, the tone quality effect of sound generated by the electroacoustic component is optimized, and the user experience is improved; the free bottom plate protrusion of speaker is in the outer bottom plate of outer frame, and the bottom plate is used for connecting circuit board, has the clearance between outer bottom plate and the circuit board, and on the one hand, this clearance can be used for placing other electron device, improves space utilization, does benefit to the inside device of mobile terminal and arranges, and on the other hand, when the circuit board is flexible circuit board, this clearance provides the space and does benefit to flexible circuit board and buckles, does benefit to the inside device of mobile terminal and arranges.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and other obvious modifications can be obtained by those skilled in the art without creative efforts.

Fig. 1 is a schematic structural diagram of an electroacoustic component according to an embodiment of the present invention.

Fig. 2 is a schematic diagram of a speaker unit of an electroacoustic assembly according to an embodiment of the present invention.

Fig. 3 is a schematic diagram of a back sound cavity of an electroacoustic assembly according to an embodiment of the present invention.

Fig. 4 is an enlarged partial cross-sectional view of an electro-acoustic assembly according to an embodiment.

Fig. 5 is a schematic structural diagram of an electroacoustic component according to a second embodiment of the present invention.

Fig. 6 is a schematic diagram of a speaker unit of an electroacoustic assembly according to a second embodiment of the present invention.

Fig. 7 is a schematic diagram of a back sound cavity of an electroacoustic assembly according to a second embodiment of the present invention.

Fig. 8 is a schematic diagram of an embodiment of an electroacoustic device according to an embodiment of the present invention.

Fig. 9 is a schematic diagram of another embodiment of an electroacoustic device according to an embodiment of the present invention.

Fig. 10 is a schematic structural diagram of a mobile terminal according to an embodiment of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Referring to fig. 1, 2 and 3, an electroacoustic assembly 100 according to an embodiment of the present invention includes a speaker unit 20 and an outer frame 32. In this embodiment, the speaker unit 20 includes an inner frame 22, a bottom plate 28 and a vibrating diaphragm 24, the inner frame 22 is fixed on the bottom plate 28, a periphery of the vibrating diaphragm 24 is fixedly connected to the inner frame 22, a sounding cavity 100 is formed between the bottom plate 28, the inner frame 22 and the vibrating diaphragm 24, and a driving member is disposed in the sounding cavity 100 and used for driving the vibrating diaphragm 24 to vibrate. Referring to fig. 2, the inner frame 22 is fixed to the bottom plate 28 by welding, etc., the inner frame 22 has certain strength, and the inner frame 22 may be a plastic member or a metal member. The inner frame 22 is formed in a closed pattern around a vertical projection of the bottom plate 28, and it is also understood that the inner frame 22 is formed in a hollow cylinder body, one end of the cylinder body is fixedly connected with the bottom plate 28, and the other end of the cylinder body is fixedly connected with the vibrating diaphragm 24, in other words, two openings at two ends of the cylinder body (the inner frame 22) are respectively sealed by the vibrating diaphragm 24 and the bottom plate 28, thereby forming a box body. In this embodiment, the diaphragm 24 is fixed to the inner wall of the inner frame 22 by means of adhesive bonding or the like, and the inner frame 22 stretches and flattens the diaphragm 24. In this embodiment, the bottom plate 28 is used to fixedly connect the circuit board 10, thereby fixing the speaker unit 20 to the circuit board 10. In one embodiment, the bottom plate 28 is fixed on the circuit board 10 by soldering, and in other embodiments, the bottom plate 28 may be adhered to the circuit board 10 by glue.

Referring to fig. 2, the driving member is accommodated in the sound-generating chamber 100, the driving member moves under the control of the driving circuit, so that the diaphragm 24 vibrates, i.e. sounds are generated, and the vibration of the diaphragm 24 causes the air around the diaphragm 24 to vibrate, so that the sounds are transmitted outwards. Furthermore, the frequency, amplitude, etc. of the vibration of the diaphragm 24 are changed according to the driving circuit, so that the speaker unit 20 emits different sounds.

Referring to fig. 1 and 3, in the present embodiment, the outer frame 32 is located on the periphery of the speaker unit 20, a back sound cavity 200 is formed between the outer frame 32 and the inner frame 22, the inner frame 22 is provided with a leakage hole 40, the leakage hole 40 is located between the diaphragm 24 and the bottom plate 28, and the leakage hole 40 communicates the back sound cavity 200 and the sound-generating cavity 100. Specifically referring to fig. 3, the outer frame 32 includes an outer top plate 322, an outer bottom plate 326 and an outer side plate 324, the outer top plate 322 abuts against the diaphragm 24, the outer top plate 322 is flush with the diaphragm 24, the outer side plate 324 is connected between the outer top plate 322 and the outer bottom plate 326, the inner frame 22, the outer top plate 322, the outer side plate 324 and the outer bottom plate 326 form the rear sound cavity 200, and a distance from the outer side plate 324 to the inner frame 22 is greater than a distance from the outer bottom plate 326 to the outer top plate 322, so that the rear sound cavity 200 is formed on a side of the speaker unit 20, the thickness of the electroacoustic assembly 100 is reduced, and the mobile terminal 300 is light and thin. In one embodiment, the weep holes 40 are round holes or bar holes. In this embodiment, the vertical distance between the outer bottom plate 326 and the outer top plate 322 is smaller than the vertical distance between the diaphragm 24 and the bottom plate 28. Specifically, the speaker unit 20 is formed to protrude from the outer bottom plate 326, that is, the bottom plate 28 protrudes from the outer bottom plate 326 to form a structure like a boss. The bottom plate 28 is used for connecting the circuit board 10, and a gap exists between the outer bottom plate 326 and the circuit board 10, on one hand, the gap can be used for placing other electronic devices, so that the space utilization rate is improved, and the arrangement of the devices inside the mobile terminal 300 is facilitated, and on the other hand, when the circuit board 10 is a flexible circuit board 10, the gap provides a space which is beneficial for the bending of the flexible circuit board 10 and the arrangement of the devices inside the mobile terminal 300.

Specifically referring to fig. 1, the speaker unit 20 is configured to vibrate to emit sound waves, so as to form sound, vibration of the speaker unit 20 causes vibration of air or gas in the sound emitting cavity 100, the speaker unit 20 is disposed in the outer frame 32, a rear sound cavity 200 is formed between the speaker unit 20 and the outer frame 32, sound absorbing particles 74 are filled in the rear sound cavity 200, the leakage holes 40 enable the rear sound cavity 200 to communicate with the sound emitting cavity 100 inside the speaker unit 20, the screen 50 is disposed in the rear sound cavity 200 to prevent the sound absorbing particles 74 from entering the leakage holes 40, a vertical projection of the screen 50 on the speaker unit 20 covers the leakage holes 40, and a size of the screen 50 is larger than a size of the leakage holes 40. The leakage hole 40 is communicated with the sounding cavity 100 and the rear sound cavity 200, and when the loudspeaker unit 20 works, the gas in the sounding cavity 100 is vibrated to be compressed or stretched; when gas is compressed, the gas enters the rear sound cavity 200 from the sound production cavity 100 through the leakage hole 40 and causes the sound absorption particles 74 in the rear sound cavity 200 to vibrate, and the friction among the sound absorption particles 74 consumes the energy of sound waves, so that the vibration effect of the gas is changed, and the characteristics of the sound waves are changed; when the gas is stretched, the gas enters the sound-emitting chamber 100 from the back sound chamber 200 through the leakage holes 40 and affects the characteristics of the sound waves propagated outward by the diaphragm 24, thereby optimizing the sound quality of the sound emitted from the electroacoustic assembly 100.

The sound-emitting cavity 100 is communicated with the back sound cavity 200 through the leakage hole 40, the energy of sound waves is consumed by friction between the sound-absorbing particles 74 in the back sound cavity 200, the vibration effect of gas is changed, the characteristics of the sound waves are changed, the tone quality effect of the sound emitted by the electroacoustic component 100 is optimized, and the user experience is improved; the bottom plate 28 of the speaker unit 20 protrudes out of the outer bottom plate 326 of the outer frame 32, the bottom plate 28 is used for connecting the circuit board 10, and a gap exists between the outer bottom plate 326 and the circuit board 10, on one hand, the gap can be used for placing other electronic devices, so that the space utilization rate is improved, and the arrangement of the devices inside the mobile terminal 300 is facilitated, on the other hand, when the circuit board 10 is the flexible circuit board 10, the gap provides a space which is beneficial to the bending of the flexible circuit board 10, and the arrangement of the devices inside the mobile terminal.

Referring to fig. 1 and fig. 2, the driving members include a first driving member 262 and a second driving member 264, the first driving member 262 is fixed on the bottom plate 28 or the inner frame 22, the second driving member 264 is fixed on the diaphragm 24, and the second driving member 264 is configured to vibrate relative to the first driving member 262 to drive the diaphragm 24 to vibrate and generate sound. Specifically, the first driving member 262 and the second driving member 264 are driven by a driving circuit on the circuit board 10 to move relatively, the first driving member 262 is fixed on the bottom plate 28 or the inner frame 22 by welding or fastening, and the second driving member 264 is fixed on the diaphragm 24 by welding or fastening, and when the first driving member 262 moves relative to the second driving member 264, the diaphragm 24 vibrates relative to the bottom plate 28 and the inner frame 22, that is, the diaphragm 24 sounds.

Referring to fig. 2, in the present embodiment, the first driving member 262 is a magnet, the second driving member 264 is a coil, the first driving member 262 includes a first magnet 262a and a second magnet 262b, the first magnet 262a is fixed on the inner frame 2222, the second magnet 262b is fixed on the bottom plate 28, the second driving member 264 is located between the first magnet 262a and the second magnet 262b, the second driving member 264 is electrically connected to the circuit board 10, and the circuit board 10 is provided with a driving circuit for driving the second driving member 264 to vibrate. Specifically, the first magnet 262a and the second magnet 262b are permanent magnets, a stable magnetic field with a constant magnetic field direction is formed between the first magnet 262a and the second magnet 262b, the coil is located in the magnetic field formed between the first magnet 262a and the second magnet 262b, and when the driving circuit of the circuit board 10 outputs a changing current signal to the coil, the changing current in the coil causes the coil to receive a force in the magnetic field, so that the coil drives the diaphragm 24 to vibrate together. In this embodiment, the first magnet 262a is fixed to the inner frame 22, the second magnet 262b is positioned inside the first magnet 262a, and a space is provided between the first magnet 262a and the second magnet 262b to place the coil. In one embodiment, the first magnet 262a and the second magnet 262b may also be electromagnets, i.e., the magnetic force of the first magnet 262a and the second magnet 262b varies according to the magnitude of the current flowing through the first magnet 262a and the second magnet 262b, so that the coil or the diaphragm 24 vibrates relative to the first driving member 262 by changing the direction and magnitude of the magnetic field of the first magnet 262a and the second magnet 262 b.

Referring to fig. 2, in the present embodiment, the leakage hole 40 is located between the vertical projection of the outer top plate 322 on the inner frame 22 and the outer bottom plate 326. Specifically, the leak hole 40 communicates the sound-emitting chamber 100 with the rear sound chamber 200, in other words, the leak hole 40 is provided in a portion of the inner frame 22 between the outer top plate 322 and the outer bottom plate 326. In one embodiment, the first magnet 262a is at least partially located on the portion of the speaker unit 20 protruding the outer bottom plate 326, so that the leakage hole 40 is disposed on the portion of the inner frame 22 located between the outer top plate 322 and the outer bottom plate 326, and the thickness of the back sound cavity 200 can be adjusted to change the thickness of the whole electroacoustic assembly 100 while ensuring the size of the back sound cavity 200, which is beneficial to the design of the electroacoustic assembly 100 with light weight and thinness.

Referring to fig. 1 and 2, in one embodiment, diaphragm 24 is provided with corrugations 72 between the periphery and the geometric center. The corrugations 72 extend in the circumferential direction of the diaphragm 24. Corrugations 72 reduce the tension of diaphragm 24, thereby making diaphragm 24 more susceptible to deforming vibrations in regions near the geometric center. The folds 72 are fixedly connected to the second driving member 264, so that the second driving member 264 can drive the diaphragm 24 to deform. The material of the diaphragm 24 may be paper, fiber material, metal material, wool material, silk material, etc.

Referring to fig. 1, in the present embodiment, the electroacoustic assembly 100 further includes sound absorbing particles 74, and the sound absorbing particles 74 are filled in the back sound cavity 200. The electroacoustic assembly 100 further comprises a screen 50, the screen 50 being disposed in the back sound chamber 200, the screen 50 being fixed to the inner frame 22, and the screen 50 covering the weep hole 40. In one embodiment, the screen 50 is a gauze. The inner frame 22 includes an outer wall 220 facing the rear sound chamber 200, and the gauze may be an opening in the outer wall 220 covering the leak hole 40. By covering the leakage holes 40 with the screen 50, the sound absorbing particles 74 are prevented from entering the sound generating chamber 100, and the sound generation of the speaker unit 20 is prevented from being influenced. The screen 50 covers the leakage holes 40, so that the sound-absorbing particles 74 can be completely filled in the rear sound cavity 200, and the sound-absorbing particles 74 do not need to be packaged and then placed in the rear sound cavity 200, thereby improving the sound quality of the electroacoustic component 100 and reducing the production cost of the electroacoustic component 100.

Referring to fig. 4, in one embodiment, a support rod 400 is disposed in the leaking hole 40, the screen 50 is attached to the support rod 400, and the support rod 400 is used to reinforce the connection between the screen 50 and the outer wall 220. Specifically, the support rod 400 assists in supporting the screen 50, the support rod 400 and the sound-absorbing particles 74 are respectively located at two opposite sides of the screen 50, the sound-absorbing particles 74 generate an extrusion force on the screen 50 due to self gravity or product shaking, if the extrusion force is too large, the screen 50 falls off from the outer wall surface 220, the support rod 400 provides a support force for the screen 50 from one side of the screen 50 departing from the sound-absorbing particles 74, the screen 50 is prevented from being deformed and falling off, the maintenance period of the product is shortened, and the maintenance cost of the product is reduced. In one embodiment, the number of the support rods 400 is two, and the support rods are arranged to cross each other.

Referring to fig. 5, 6 and 7, a difference between the electroacoustic component 100 according to the second embodiment of the present invention and the first embodiment is that the leakage holes 40 include a first leakage hole 42 and a second leakage hole 44, the first leakage hole 42 is located between the vertical projection of the first magnet 262a on the inner frame 22 and the diaphragm 24, and the second leakage hole 44 is located between the vertical projection of the first magnet 262a on the inner frame 22 and the outer bottom plate 326. Referring specifically to fig. 5, the first leakage hole 42 and the second leakage hole 44 cooperate to increase the gas exchange rate between the sounding cavity 100 and the rear sound cavity 200, which is beneficial to improving the sound quality. In this embodiment, the first magnet 262a is located at the portion of the inner frame 22 corresponding to the rear sound cavity 200, the first leakage hole 42 and the second leakage hole 44 are respectively located at two sides of the first magnet 262a, the first magnet 262a separates the first leakage hole 42 from the second leakage hole 44, and the first magnet 262a exchanges gas with the rear sound cavity 200 from different positions of the sounding cavity 100, so that the gas exchange effect in the sounding cavity 100 is uniform, and the sound quality improvement effect is facilitated.

Specifically to fig. 7, the first magnet 262a includes a first sidewall 2622 facing the diaphragm 24, the inner wall of the first leakage hole 42 is flush with the first sidewall 2622, thereby maximizing the size of the first leakage hole 42, the first leakage hole 42 is located between the vertical projections of the diaphragm 24 and the first magnet 262a on the inner frame 22, on the premise of not affecting the strength of the frame, increasing the size of the first leakage hole 42 is beneficial to increasing the amount of gas entering and exiting the back sound cavity 200 and the sound-generating cavity 100 per unit time, i.e. the rate of gas entering and exiting the back sound cavity 200 and the sound-generating cavity 100, thereby enhancing the sound quality improvement effect of the back sound cavity 200 on the electroacoustic assembly 100.

Referring to fig. 7, in the present embodiment, the first magnet 262a further includes a second side wall 2624 facing the bottom plate 28, an inner wall of the second leakage hole 44 is flush with the second side wall 2624, so as to maximize a size of the second leakage hole 44, the second leakage hole 44 is located between the first magnet 262a and the circuit board 10, and on the premise of not affecting the strength of the frame, increasing the size of the second leakage hole 44 is beneficial to increasing the amount of gas entering and exiting the back sound cavity 200 and the sound-generating cavity 100 per unit time, i.e. the rate of gas entering and exiting the back sound cavity 200 and the sound-generating cavity 100, so as to enhance the sound quality improvement effect of the back sound cavity 200 on the electroacoustic assembly 100.

Referring to fig. 8, an electroacoustic device 200 according to an embodiment of the present invention further includes a circuit board 10 and an electroacoustic component 100 according to an embodiment of the present invention, the bottom plate 28 is fixedly connected to the circuit board 10, and the circuit board 10 is provided with a driving circuit for driving the diaphragm 24 to vibrate and generate sound. Specifically, the Circuit Board 10 is a Printed Circuit Board (PCB) 10, in one embodiment, the Circuit Board 10 may also be a Flexible Printed Circuit (FPC) 10, and the Circuit Board 10 is provided with a driving Circuit for driving the speaker unit 20 to generate sound. In one embodiment, when the electro-acoustic assembly 100 is applied to the mobile terminal 300, the circuit board 10 may be a main board of the mobile terminal 300. There is the clearance between outer bottom plate 326 and the circuit board 10, and on the one hand, this clearance can be used for placing other electron device, improves space utilization, does benefit to the inside device of mobile terminal 300 and arranges, and on the other hand, when circuit board 10 is flexible circuit board 10, this clearance provides the space and does benefit to flexible circuit board 10 and buckles, does benefit to the inside device of mobile terminal 300 and arranges.

Referring to fig. 9, in one embodiment, the circuit board 10 includes a first surface 104, the circuit board 10 is provided with a receiving groove 102 recessed in the first surface 104, the speaker unit 20 is at least partially received in the receiving groove 102, and the external bottom plate 326 contacts the first surface 104. In this embodiment, the receiving slot 102 is a groove opened on the surface of the circuit board 10, in one embodiment, the depth of the receiving slot 102 is the same as the size of the speaker unit 20 protruding from the external bottom plate 326, and the portion of the speaker unit 20 protruding from the external bottom plate 326 is completely received in the receiving slot 102, in other words, the total thickness of the circuit board 10 and the electroacoustic device 100 (the thickness of the electroacoustic device 200) is the sum of the thicknesses of the circuit board 10 and the back sound cavity 200, so that the thickness of the electroacoustic device 200 is reduced, which is beneficial to the design of thinning the electroacoustic device 200.

Referring to fig. 9, an embodiment of the invention further provides a mobile terminal 300 including the electroacoustic device 200 according to the embodiment of the invention. Specifically, the mobile terminal 300 further includes a housing 92, and the electroacoustic device 200 is fixed to a bottom end of the housing 92. It is understood that the mobile terminal 300 may be a mobile phone, a tablet computer, a notebook computer, etc.

While the invention has been described with reference to a number of illustrative embodiments, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention.

Claims

1. An electro-acoustic assembly secured to a circuit board, the electro-acoustic assembly comprising:

the outer frame is positioned on the periphery of the loudspeaker monomer and comprises an outer top plate, an outer bottom plate and an outer side plate connected between the outer top plate and the outer bottom plate, the outer top plate is abutted against the vibrating diaphragm, and a rear sound cavity is formed among the outer top plate, the outer side plate, the outer bottom plate and the inner frame, so that the rear sound cavity is formed on the side edge of the loudspeaker monomer; the inner frame is provided with a leakage hole for communicating the rear sound cavity with the sounding cavity, the vertical distance between the outer bottom plate and the outer top plate is smaller than that between the vibrating diaphragm and the bottom plate, and the loudspeaker monomer forms a structure protruding from the outer bottom plate; when the loudspeaker single body works, the gas in the sounding cavity is vibrated to be compressed or stretched; when the gas is compressed, the gas enters the rear sound cavity from the sound-generating cavity through the leakage hole and causes the sound-absorbing particles in the rear sound cavity to vibrate, the friction among the sound-absorbing particles consumes the energy of sound waves, the vibration effect of the gas is changed, and the characteristics of the sound waves are changed; when the gas is stretched, the gas enters the sounding cavity from the back sound cavity through the leakage hole and influences the characteristics of sound waves transmitted outwards by the vibrating diaphragm, so that the sound quality effect of sound emitted by the electroacoustic component is optimized;

when the electroacoustic component is used for being connected with the circuit board, the loudspeaker single body is accommodated in the accommodating groove of the circuit board, and the outer bottom plate is contacted with the first surface of the circuit board;

wherein, electroacoustic component still includes the screen cloth, the screen cloth is located in the back sound chamber, the screen cloth is fixed in on the internal frame, just the screen cloth covers let out the leakage hole, still be equipped with the supporting rod in the leakage hole, screen cloth laminating supporting rod, supporting rod are used for the supplementary flat screen cloth that props.

2. The electro acoustic assembly of claim 1, wherein the leak hole is located between a perpendicular projection of the outer top plate on the inner frame and the outer bottom plate.

3. The electro-acoustic assembly of claim 2, wherein the speaker unit further includes a driving member, the driving member is accommodated in the sound-generating cavity, the driving member includes a first driving member and a second driving member, the first driving member is fixed on the bottom plate or the inner frame, the second driving member is fixed on the diaphragm, and the second driving member is configured to vibrate relative to the first driving member to drive the diaphragm to generate sound by vibration.

4. The electro acoustic assembly of claim 3, wherein the first driver is a magnet and the second driver is a coil, the first driver including a first magnet and a second magnet, the first magnet being fixed to the inner frame and the second magnet being fixed to the base plate, the second driver being located between the first magnet and the second magnet, the second driver being electrically connected to a driving circuit for driving the second driver to vibrate.

5. The electro acoustic assembly of claim 4, wherein the leakage holes comprise a first leakage hole and a second leakage hole, the first leakage hole being located between a perpendicular projection of the first magnet on the inner frame and the diaphragm, the second leakage hole being located between a perpendicular projection of the first magnet on the inner frame and the outer bottom plate.

6. The electro-acoustic assembly of claim 5, wherein the first magnet includes a first sidewall facing the diaphragm, an inner wall of the first leak hole being flush with the first sidewall; the first magnet further includes a second sidewall facing the bottom plate, an inner wall of the second leakage hole being flush with the second sidewall.

7. The electro-acoustic assembly in accordance with claim 1, further comprising sound absorbing particles filled in said back sound cavity.

8. An electro-acoustic apparatus comprising a circuit board and the electro-acoustic assembly as claimed in any one of claims 1 to 7, wherein said base board is fixedly connected to said circuit board, and said circuit board is provided with a driving circuit for driving said diaphragm to vibrate and generate sound.

9. The electro acoustic device in accordance with claim 8, wherein said circuit board includes a first surface, said circuit board having a receiving cavity recessed into said first surface, said speaker unit being at least partially received in said receiving cavity, said external base plate contacting said first surface.

10. A mobile terminal characterized by comprising the electro-acoustic apparatus of any one of claims 8 to 9.