WO2020224277A1

WO2020224277A1 - Sound production apparatus

Info

Publication number: WO2020224277A1
Application number: PCT/CN2019/129015
Authority: WO
Inventors: 张北京; 蔡晓东
Original assignee: 歌尔股份有限公司
Priority date: 2019-05-08
Filing date: 2019-12-27
Publication date: 2020-11-12
Also published as: CN110198513A

Abstract

The present invention provides a sound production apparatus, comprising an outer shell provided with an accommodating space, and a sound production unit mounted and fixed in an accommodating cavity, wherein the sound production unit comprises a vibration diaphragm; a first cavity is formed in a space between the front side of the vibration diaphragm and the outer shell; a second cavity is formed in a space between the back side of the vibration diaphragm and the outer shell; a part of the space in the second cavity is configured to be a sound absorption cavity; the sound absorption cavity is enclosed together by a supporting structure fixed in the second cavity and an air-permeable isolation member combined with the supporting structure; each surface of the supporting structure is at least partially configured in an open mode and used for assembling the air-permeable isolation member; the sound absorption cavity is filled with a sound absorption material. By means of the technical solution of the present invention, the sound absorption cavity is high in air permeability, the utilization rate of the space in the second cavity can be improved, and the acoustic performance of a product in a low frequency band is greatly improved.

Description

A sounding device

Technical field

The invention relates to the technical field of electroacoustic products, in particular to a sound generating device.

Background technique

Generally, in order to obtain a better acoustic effect, especially in order to obtain a better low frequency effect, a speaker module generally fills the back cavity of the module with sound-absorbing particles. In the prior art, for the design of partial filling of sound-absorbing particles, the main method is to set a separate filling area in the cavity formed by the module shell, and isolate the sound-absorbing particles from the sound generation by means of hot-melt mesh or plug-in mesh. unit.

However, this approach has certain drawbacks: On the one hand, the overall air permeability of the current product design is poor. The separate filling area and the sound unit are only connected through the mesh between the two, and cannot form a vibrating sound wave ventilation circuit, which greatly affects the expansion effect of the sound-absorbing particles. This is because the accumulation of particles makes the first contact with the end of the sounding unit to be able to fully expand, and the far away part of the particles does not have the effect of expansion and even has a counter effect due to the accumulation. On the other hand, the acoustic performance of the speaker module has limited improvement. The mesh cloth is mainly fixed by hot melt or bonding, and these two processes require that the fixed surface must be flat, so the setting of the filling area is largely limited by the cavity structure, and the cavity space inside the module is difficult It is fully utilized and the filling volume is too small.

Therefore, it is necessary to find a new solution to improve the above-mentioned shortcomings in the prior art and meet the requirements of speaker performance.

Summary of the invention

The main purpose of the present invention is to provide an acoustic device, which aims to solve the problems of poor air permeability of the sound absorption area as a whole and limited low frequency improvement effect due to the limitation of the cavity structure in the prior art.

In order to achieve the above objective, the present invention provides an acoustic device, which includes an external housing with a housing space and a sounding unit installed and fixed in the housing cavity. The sounding unit includes a diaphragm, and the front side of the diaphragm is connected to The space between the outer casings forms a first cavity, and the space between the back side of the diaphragm and the outer casing forms a second cavity, wherein,

A part of the space in the second cavity is set as a sound-absorbing cavity; the sound-absorbing cavity is enclosed by a supporting structure fixed in the second cavity and a breathable spacer combined with the supporting structure; Each surface of the supporting structure is at least partially open, for assembling the air-permeable isolator; the sound-absorbing cavity is filled with sound-absorbing material.

Preferably, the supporting structure is made of metal.

Preferably, the support structure is formed by metal powder injection molding.

Preferably, the supporting structure is made of plastic material and is integrally injection molded.

Preferably, the supporting structure is a regular/irregular polyhedral structure.

Preferably, the outer contour of the supporting structure is a regular rectangular parallelepiped frame structure, wherein the supporting structure is surrounded by a supporting arm into six faces, and the six faces are arranged in an open manner; the air-permeable partition is correspondingly provided with Six, respectively, are fixed on the support arms surrounding each surface.

Preferably, a fixing part fixed to the supporting structure is provided on the outer shell, and the fixing part is arranged corresponding to an edge position of the supporting structure.

Preferably, the outer contour of the support structure is a regular rectangular parallelepiped frame structure, the fixing portion is a protrusion set corresponding to the corner position of the support structure; the protrusion is integrally formed with the outer casing, and And the supporting structure are fixed together by gluing or hot melt.

Preferably, the air-permeable spacer is a split structure, which is respectively fixed on each surface of the support structure; or, the air-permeable spacer is an integrally formed structure.

Preferably, the air-permeable spacer is a metal mesh, which is integrally formed with the support structure through a metal powder injection process; or, the air-permeable spacer is a non-metal mesh, which is bonded and fixed or combined with the support structure by injection molding.

Preferably, the sound-absorbing material is porous sound-absorbing particles, and the maximum pore size of the mesh of the air-permeable spacer is smaller than the minimum particle size of the sound-absorbing particles.

Preferably, the outer shell is provided with a sound outlet, and the airflow generated by the vibration of the diaphragm is radiated from the sound outlet on the front side of the diaphragm via the first cavity; The air flow generated by the vibration of the diaphragm is communicated with the sound-absorbing cavity via the air-permeable isolator on the back side of the diaphragm.

Preferably, the sound outlet is arranged at a position of the outer casing facing the diaphragm; or the sound outlet is arranged on a side of the outer casing.

Preferably, the outer shell includes a first shell and a second shell that are assembled with each other; or, the outer shell includes a first shell, a second shell, and a second shell that are assembled with each other. Three shells.

In the sound generating device of the technical solution of the present invention, the sound-absorbing cavity is enclosed by a supporting frame with at least partially open design on each surface and a breathable partition. For a sound-emitting device partially filled with sound-absorbing materials in the second cavity, the sound-absorbing cavity Each surface of the body can receive the sound waves generated by the vibration of the diaphragm, that is, a full-permeable filling cavity is formed. Compared with the prior art, the overall air permeability of the sound-absorbing area is improved, and the sound-absorbing material can be fully expanded. The volume of the virtual back cavity is increased to a greater extent.

Furthermore, the support frame of the sound device of the technical scheme of the present invention can be made by a metal powder injection molding process. Compared with the existing process, it will not be restricted by the cavity structure, hot melt process and processing accuracy, and can be more adequate. The use of the space in the second cavity further improves the low-frequency acoustic performance of the product.

Description of the drawings

In order to explain the embodiments of the present invention or the technical solutions in the prior art more clearly, the following will briefly introduce the drawings that need to be used in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only These are some embodiments of the present invention. For those of ordinary skill in the art, without creative work, other drawings can be obtained based on the structures shown in these drawings.

Figure 1 is an exploded view of the structure of an embodiment of the acoustic device of the present invention;

2 is a schematic cross-sectional view of an embodiment of the acoustic device of the present invention;

Figure 3 is a perspective view of an embodiment of the acoustic device of the present invention.

Description with icon number:

1. External housing, 10, sound outlet, 101, first cavity, 102, second cavity, 11, first housing, 12, second housing, 121, fixing part, 2. sounding unit, 3. Support structure, 31. Support arm, 4. Breathable isolator, 5. Diaphragm.

The realization of the objectives, functional characteristics and advantages of the present invention will be further described in conjunction with the embodiments and with reference to the accompanying drawings.

Detailed ways

The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative work shall fall within the protection scope of the present invention.

It should be noted that all directional indicators (such as up, down, left, right, front, back...) in the embodiments of the present invention are only used to explain the relationship between components in a particular posture (as shown in the accompanying drawings). If the relative position relationship, movement situation, etc. change, the directional indication will change accordingly.

In addition, the descriptions related to "first", "second", etc. in the present invention are only used for descriptive purposes, and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of indicated technical features. Therefore, the features defined with "first" and "second" may explicitly or implicitly include at least one of the features.

The present invention proposes an acoustic device, which includes an external casing with a receiving space and a sounding unit installed and fixed in the receiving cavity. The sounding unit includes a diaphragm. The space between the front side of the diaphragm and the outer casing forms a second A cavity. The space between the back side of the diaphragm and the outer casing forms a second cavity. In order to solve the problems of insufficient overall air permeability of the sound-absorbing area in the prior art and limited improvement in acoustic performance due to the limitation of the module housing structure, in the technical solution of the present invention, part of the space in the second cavity is set as a sound-absorbing cavity , The sound-absorbing cavity is enclosed by a supporting structure fixed in the second cavity and a gas-permeable spacer combined with the supporting structure. Each surface of the supporting structure is at least partially open to assemble the gas-permeable spacer The inside of the sound-absorbing cavity is filled with sound-absorbing material.

Examples:

As shown in Fig. 1, Fig. 2 and Fig. 3 together, the sound generating device of this embodiment specifically includes an outer housing 1. The outer housing 1 includes a first housing 11 and a second housing 12 assembled with each other. After the first shell 11 and the second shell 12 are assembled, a receiving cavity is formed, and the sound generating unit 2 is installed and fixed in the receiving cavity. The sounding unit 2 further includes a diaphragm 5, and the sounding unit 2 divides the cavity formed by the outer casing 1 into two cavities. Specifically, the space between the front side of the diaphragm 5 and the outer casing 1 forms a first cavity The body 101 is the front acoustic cavity of the sound device. The first cavity 101 communicates with the sound outlet 10. The sound waves generated by the vibration of the diaphragm 5 radiate to the outside from the sound outlet 10 through the first cavity 101; the back of the diaphragm 5 The space between the side and the outer casing 1 forms a second cavity 102, the second cavity 102 and the first cavity 101 are isolated from each other, as the back acoustic cavity of the sound device, the second cavity 102 is an acoustically sealed structure , The airflow generated by the vibration of the diaphragm on the back side is enclosed in the space of the second cavity 102 to avoid acoustic short circuit.

In order to optimize the acoustic performance of the sound generating device in the low frequency band, part of the space in the second cavity 102 is set as a sound-absorbing cavity, and the virtual volume in the cavity is increased by the sound-absorbing material. In this embodiment, the suction cavity is specifically enclosed by the supporting structure 3 fixed in the second cavity 102 and the breathable spacer 4 assembled with the supporting structure 3. Wherein, the supporting structure 3 provides the outer frame of the sound-absorbing cavity, and the air-permeable spacer 4 mainly contributes to the air flow between the sound-emitting unit and the sound-absorbing material and prevents the sound-absorbing material from escaping to the sound-emitting unit 2. In order to enable the sound-absorbing material to fully contact the sound-emitting unit 2 and improve the air permeability of the entire sound-absorbing cavity, in this embodiment, each surface of the support structure 3 is set to be at least partially open, that is, in the different support structures. There are at least partial openings on the surface of the vent for assembling the air-permeable spacer 4, which can ensure that the air flow generated on the back side of the diaphragm 5 passes through the air-permeable spacer 4 on each surface of the entire sound-absorbing cavity to form a ventilating circuit, and the sound-absorbing The cavities are connected. Compared with the prior art method where only one side or part of the surface is provided with a mesh cloth, the sound absorbing material near the end of the sound unit and the sound absorbing material far away from the end of the sound unit can effectively expand the capacity.

Optionally, the supporting structure 3 can be made of metal, plastic or other materials. Preferably, when a metal material is used for molding, the support structure 3 can be molded by a metal powder injection molding process (MIM). Among them, the metal powder injection molding process is a new type of powder metallurgy near-net forming technology formed by introducing modern plastic injection molding technology into the field of powder metallurgy. The basic process is: first, the solid powder and the organic binder are uniformly mixed After being granulated, it is injected into the mold cavity with an injection molding machine under the heating and plasticizing state (~150℃) to be solidified, and then the binder in the formed blank is removed by chemical or thermal decomposition, and finally sintered Densification obtains the final product. The product formed by this process has the same complex shape and high precision as the product obtained by plastic injection molding, and has physical, chemical and mechanical properties close to that of forgings. It can be equipped with a separate fillable area in accordance with the complex spatial structure of the back acoustic cavity. A metal support structure with a certain strength is independent of the inside of the module cavity and does not make large-area contact with one or more surfaces of the inner cavity wall, which can ensure that most areas of the sound-absorbing cavity can be combined with the breathable spacer 4. That is to say, compared with the existing process technology, the use of this process will not be restricted by the cavity structure, hot melt process and processing accuracy, and it is easy to separately form various complex and high-precision support structures 3 in the rear acoustic cavity. It is of great help to improve the low-frequency acoustic performance of the speaker module.

Of course, if the supporting structure 3 is made of plastic material, it can also be integrally formed by an injection molding process. This process is a more traditional process, so I won't repeat it here.

In the specific implementation, the supporting structure 3 can be a regular polyhedral structure or an irregular polyhedral structure. Taking the example shown in this embodiment as an example, the supporting structure 3 is set as a regular cuboid structure (ie, a hexahedron), and its overall It is a frame structure composed of multiple groups of support arms 31, including six different surfaces in the up and down, left and right directions, and front and rear directions, and these six surfaces are all open design, so that six breathable isolations can be set The pieces 4 correspond to each surface of the support structure 3 and are fixed together with the support arms 31 correspondingly. It is easy to understand that the number, size and shape of the breathable spacers 4 can be flexibly adjusted according to the specific conditions of each surface of the support structure 3. Except for the frame formed by the support arm 31, all six surfaces outside the frame can receive the vibrating sound waves of the sound generating unit, which can form a fully air-permeable sound-absorbing cavity, so as to achieve the effect of sufficient expansion of the sound-absorbing material, which can increase the virtual The volume of the back cavity.

Those skilled in the art should understand that the support structure 3 needs to be fixed in the second cavity 201, that is, it should be connected and fixed with the shell wall of the outer casing 1. In this embodiment, as shown in FIGS. 1 and 2, the outer The housing 1 is provided with a fixing portion 121 fixed to the supporting structure 3. The fixing portion 121 may be a convex structure extending from the inner wall of the outer casing 1 in the direction of the supporting structure 3, and the convex structure connects the supporting structure 3 and the outer casing 1. In a specific implementation, the raised structure can be set as a stepped bracket, or can be a raised connecting structure extending perpendicular to the inner surface of the shell wall to the support structure 3, etc. The above-mentioned protrusions can be integrally formed with the outer shell 1 and fixed with the supporting structure 3 by means of glue or hot melt. Of course, it can also be a raised structure designed separately. It may also be a protrusion extending from the inner wall surface of the outer casing 1 to the outer surface direction (equivalent to a structure of a sink groove), and the part of the supporting structure 3 connected with the outer casing 1 may be directly accommodated in the protrusion.

In addition, in order to ensure that the area is as large as possible, and to be firmly fixed to the supporting structure 3, a preferred embodiment is that the fixing portion 121 can be symmetrically arranged at the edge of the supporting structure 3, as shown in Figures 1 and 2 for example. In fact, the four corner positions can also be two corner positions on the same side, and basic fixed connection can also be achieved. For the technical solution, the specific manner and position of the support structure 3 and the outer casing 1 to achieve fixation are not limited, nor are they used to limit the scope of implementation of the technical solution.

When assembling the sound device of this embodiment, the support structure 3 can be separately molded by a metal powder injection molding process. The five surfaces of the support structure 3 are provided with air-permeable spacers 4, and the air-permeable spacers 4 are never combined. Fill the side with sound-absorbing material, and then cover the air-permeable spacer 4 on this surface, thus forming an independent sound-absorbing cavity. The sound-absorbing cavity is fixed to the outer casing 1 by the fixing portion 121 described above. After processing this part, proceed to the assembly of the sound unit 2 and the outer casing 1, so that it will not be directly or indirectly filled into the finished module due to the existing process, which may be caused by the adhesion of sound-absorbing particles, overflow, etc. Poor performance and appearance are discarded, and the production process is simple, which can reduce production costs.

It is understandable that the air-permeable spacer 4 may be a split structure, that is, a plurality of air-permeable spacers of equal numbers are arranged corresponding to different surfaces, and then fixed on each surface of the supporting structure 3 respectively. However, it is not limited to this method. It can also be an integrally formed ring structure, or an integrally formed ring-shaped air-permeable spacer with four parts of the front and rear sides and left and right sides, and then two air-permeable spacers on the upper top surface and the lower bottom surface are respectively provided. Spacer.

The specific material of the air-permeable spacer 4 can be flexibly selected. For example, the air-permeable spacer 4 can be a metal mesh, which can be integrally formed with the support structure 3 through a metal powder injection process. Or, the air-permeable spacer 4 is a non-metallic mesh, such as a dust-proof net, non-woven fabric, filter paper, DuPont paper, and other air-permeable mesh members. When the above-mentioned non-metallic material breathable spacer is selected, it can be bonded and fixed with the support structure 3 or combined with injection molding.

In the sound generating device of the present invention, the sound absorbing material in the sound absorbing cavity may be porous sound absorbing particles, such as particles of zeolite, amorphous carbon, molecular sieve, spherical carbon molecules, and the like. Those skilled in the art can understand that, since the air-permeable spacer 4 is responsible for the function of isolating the sound generating unit 2 from the sound-absorbing particles, the maximum aperture of the mesh distributed on the air-permeable spacer 4 should be smaller than the smallest of the sound-absorbing particles. Particle size, which can ensure that the sound-absorbing particles will not escape from the mesh to the sound unit 2.

It should be noted that the sound emitting device shown in this embodiment is a side sound emitting device, and the sound outlet 10 is provided on the side of the outer casing 1. For the current portable terminal design that is generally miniaturized and thinner, this The sound device with sound structure has wider applicability. However, the sound outlet 10 can still be arranged at the position of the outer casing 1 facing the diaphragm 5, that is, the sound is being emitted, which does not affect the realization of the technical solution of the present invention.

In addition, in the sound generating device shown in this embodiment, the external casing 1 specifically includes a first casing 11 and a second casing 12 that are assembled with each other, wherein the sound outlet 5 and the fixing portion 121 are both provided in the On the second housing 12, the structure of the external housing and the housing corresponding to each component are not limited by this. For example, the outer shell 1 may also be composed of three-part shells, including a first shell, a second shell, and a third shell that are assembled with each other. The specific arrangement of the sound outlet and the like are those skilled in the art. It is well known and will not be repeated here.

Furthermore, in the sound generating device shown in this embodiment, the support structure 3, except that the corner position is connected with the fixed portion 121, the rest of the main body on the six faces formed by the support arm 31 are all open, and the air permeability can be obtained. Great improvement. However, in specific implementation, the open areas on different surfaces of the support structure 3 may be uneven. For example, considering the strength requirements of the support structure 3, the support arms on the top surface of the support structure 3 may extend along the plane. A relatively small opening is formed for assembling different design schemes such as the air-permeable spacer 4, etc., as long as it can ensure that each surface can allow the air flow on the back side of the diaphragm to pass.

The above descriptions are only the preferred embodiments of the present invention, and do not limit the scope of the present invention. Under the inventive concept of the present invention, equivalent structural transformations made by using the contents of the description and drawings of the present invention, or direct/indirect use Other related technical fields are included in the scope of patent protection of the present invention.

Claims

A sounding device includes an outer casing with a containing space and a sounding unit installed and fixed in the containing cavity. The sounding unit includes a diaphragm, and a gap between the front side of the diaphragm and the outer casing The space forms a first cavity, and the space between the back side of the diaphragm and the outer casing forms a second cavity, characterized in that:

A part of the space in the second cavity is set as a sound-absorbing cavity; the sound-absorbing cavity is enclosed by a supporting structure fixed in the second cavity and a breathable spacer combined with the supporting structure; Each surface of the supporting structure is at least partially open, for assembling the air-permeable isolator; the sound-absorbing cavity is filled with sound-absorbing material.
The sound emitting device according to claim 1, wherein the supporting structure is made of metal.
3. The sound generating device according to claim 2, wherein the support structure is injection molded by metal powder.
The sound generating device according to claim 1, wherein the supporting structure is made of plastic material and is integrally injection molded.
The sounding device according to claim 1, wherein the supporting structure is a regular/irregular polyhedron structure.
The sounding device according to claim 5, wherein the outline of the supporting structure is a regular rectangular parallelepiped frame structure, wherein the supporting structure is surrounded by supporting arms to form six faces, and all six faces are open Type arrangement; The breathable spacer is correspondingly provided with six, respectively fixed on the support arms surrounding each surface.
The sounding device according to claim 1, wherein a fixing part fixed to the supporting structure is provided on the outer casing, and the fixing part is arranged corresponding to an edge position of the supporting structure.
The sounding device according to claim 7, wherein the outline of the supporting structure is a regular rectangular parallelepiped frame structure, and the fixing portion is a protrusion corresponding to the corner of the supporting structure; the convex It is integrally formed with the outer shell, and fixed with the supporting structure by gluing or hot melt.
The sound emitting device according to claim 1, wherein the air-permeable isolator has a split structure and is fixed on each surface of the support structure respectively;

Alternatively, the air-permeable spacer is an integrally formed structure.
The sound generating device according to claim 1, wherein the air-permeable spacer is a metal mesh, which is integrally formed with the support structure through a metal powder injection process;

Alternatively, the air-permeable spacer is a non-metal mesh, which is bonded and fixed with the support structure or combined with injection molding.
The sound generating device according to claim 1, wherein the sound-absorbing material is porous sound-absorbing particles, and the maximum pore size of the mesh of the air-permeable spacer is smaller than the minimum particle size of the sound-absorbing particles.
The sound generating device according to any one of claims 1-11, wherein the outer shell is provided with a sound outlet, and the air flow generated by the vibration of the diaphragm passes through the front side of the diaphragm. The first cavity radiates outward from the sound outlet; the airflow generated by the vibration of the diaphragm is in communication with the sound-absorbing cavity via the air-permeable isolator on the back side of the diaphragm.
The sound emitting device according to claim 12, wherein the sound outlet is arranged at a position of the outer casing facing the diaphragm;

Alternatively, the sound outlet is provided on the side of the outer casing.
The sound generating device according to claim 12, wherein the outer casing comprises a first casing and a second casing assembled with each other;

Alternatively, the outer casing includes a first casing, a second casing, and a third casing assembled with each other.