Sound absorption assembly, sound production device and electronic equipment

Abstract

The invention belongs to the technical field of electroacoustics, and particularly relates to a sound absorption assembly, a sound production device and electronic equipment, and the sound absorption assembly comprises a shell, and active carbon powder particles with the average particle size of 1-50 microns and sound absorption particles with the average particle size of 200-450 microns which are mixed and filled in an internal accommodating space of the shell, the sound-absorbing particles are sphere-like particles formed by bonding a plurality of molecular sieve powder particles, the surface layers of the active carbon powder particles have hydrophobic structures, the bulk density of the active carbon powder particles is 0.2-0.6 g / cm < 3 >, and the ratio of the bulk density of the active carbon powder particles to the bulk density of the sound-absorbing particles is 0.7-1; the shell is provided with air holes communicated with the containing space, and the hole diameter of the air holes is smaller than the minimum particle diameter of the activated carbon powder particles. The activated carbon particles can be filled in gaps generated by accumulation of the sound-absorbing particles, the low-frequency acoustic performance of the sound production device is improved, even if the sound-absorbing particles are broken, the shell can play a good isolation role, and the sound production monomers are prevented from being polluted by broken powder.

Description

Technical Field

[0001] This invention belongs to the field of electroacoustic technology, and specifically relates to a sound-absorbing component, a sound-generating device, and an electronic device. Background Technology

[0002] Currently, to address the issue of reduced low-frequency performance in loudspeakers due to decreased rear acoustic cavity space, technicians typically fill the rear acoustic cavity with porous sound-absorbing particles to virtually enlarge the acoustic resonant space. However, the average particle size of the sound-absorbing particles filling the rear acoustic cavity is generally 300 μm to 400 μm. When these particles accumulate, they create gaps between them, failing to effectively fill the rear acoustic cavity volume, thus reducing the acoustic improvement effect. Furthermore, during loudspeaker operation, the sound-absorbing particles move with the airflow in the rear acoustic cavity, colliding and rubbing against the cavity walls or between the particles themselves. This can easily lead to breakage and detachment of the sound-absorbing particles, contaminating the driver unit.

[0003] Therefore, existing speakers still need improvement. Summary of the Invention

[0004] The purpose of this invention is to provide a sound-absorbing component, a sound-generating device, and an electronic device. The sound-absorbing component provided by this invention can adopt a full-coverage structure design, which can completely fill and fit all the spaces of the rear acoustic cavity. Activated carbon powder and sound-absorbing particles are mixed and filled inside the shell of the sound-absorbing component. The activated carbon powder can fill the gaps created by the accumulation of sound-absorbing particles, which greatly increases the filling amount of sound-absorbing material in the sound-absorbing component, further improving the low-frequency acoustic performance of the sound-generating device. Moreover, the sound-absorbing material is confined and housed inside the shell of the sound-absorbing component. Even if the sound-absorbing particles break during operation, the shell can still play a good isolation role, preventing the broken powder from contaminating the sound-generating unit and improving the durability and service life of the sound-absorbing material.

[0005] The first aspect of this invention provides a sound-absorbing component, comprising a shell having a receiving space and activated carbon powder and sound-absorbing particles mixed and filled within the receiving space. The activated carbon powder has a hydrophobic surface structure, the average particle size D50 of the activated carbon powder is 1 μm to 50 μm, and the bulk density of the activated carbon powder is 0.2 g / cm³. 3 ~0.6g / cm 3 The ratio of the bulk density of the activated carbon powder to the bulk density of the sound-absorbing particles is between 0.7 and 1; the sound-absorbing particles are spherical particles formed by bonding multiple molecular sieve powder particles, and the average particle size D50 of the sound-absorbing particles is 200 μm to 450 μm; the shell is provided with vent holes that connect to the accommodating space, and the pore size of the vent holes is smaller than the minimum particle size of the activated carbon powder.

[0006] In some embodiments, the hydrophobic structure of the activated carbon powder includes at least one of silane hydrophobic groups, fluorine-containing atom grafted groups, metal oxide hydrophobic layers, polymer coating layers, biomass hydrophobic layers, graphene layers, and carbon nanotube layers.

[0007] In some embodiments, the volume ratio of the sound-absorbing particles to the activated carbon powder is 1:0.5~1.

[0008] In some embodiments, the average particle size D50 of the sound-absorbing particles is 200 μm to 450 μm.

[0009] In some embodiments, the average particle size D50 of the activated carbon powder is 1 μm to 50 μm.

[0010] In some embodiments, the thickness of the housing is 0.1 mm to 0.5 mm.

[0011] In some embodiments, the housing includes a main housing and a cover housing, the main housing and the cover housing together forming the receiving space, and at least one of the main housing and the cover housing is a breathable structure having the breathable holes.

[0012] In some embodiments, the air permeability of the breathable structure is 1000 mm / s to 1500 mm / s.

[0013] In some embodiments, the bursting strength of the breathable structure is ≥1 N.

[0014] In some embodiments, the material of the breathable structure includes at least one of woven fiber fabric, nonwoven fabric, hot melt mesh, open-cell polymer foam material, and core-pore membrane.

[0015] In some embodiments, one of the main shell and the cover shell is a non-breathable structure, and the material of the non-breathable structure includes at least one of the following: polypropylene, polyethylene, polycarbonate, polyvinyl chloride, acrylonitrile-butadiene-styrene copolymer, and polyamide membrane or sheet.

[0016] In some embodiments, the cover housing and the main housing are bonded together by adhesive or hot melt bonding.

[0017] A second aspect of the present invention also provides a sound-generating device, the sound-generating device comprising a housing having an internal space and a sound-generating unit disposed inside the housing, the sound-generating unit cooperating with the housing to define a front sound cavity and a rear sound cavity within the internal space of the housing, the sound-absorbing component described in the first aspect being disposed within the rear sound cavity.

[0018] A third aspect of the present invention also provides an electronic device, the electronic device comprising the sound-generating device described in the second aspect.

[0019] The sound-absorbing component of this invention adopts a full-coverage structure design, which can completely fill and fit all the spaces of the rear acoustic cavity. Activated carbon powder and sound-absorbing particles are mixed and filled inside the shell of the sound-absorbing component. The activated carbon powder can fill the gaps created by the accumulation of sound-absorbing particles, which greatly increases the filling amount of sound-absorbing material in the sound-absorbing component and further improves the low-frequency acoustic performance of the sound-generating device. Moreover, the sound-absorbing material is confined inside the shell of the sound-absorbing component. Even if the sound-absorbing particles break during operation, the shell can still play a good isolation role, avoiding the contamination of the sound-generating unit by the broken powder, and improving the durability and service life of the sound-absorbing material.

[0020] The above description is merely an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention and to implement it in accordance with the contents of the specification, and in order to make the above and other objects, features and advantages of the present invention more apparent and understandable, specific embodiments of the present invention are described below. Attached Figure Description

[0021] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0022] Figure 1 This is a schematic diagram of the structure of the sound-generating device in some embodiments of the present invention; Figure 2 The HOHD curves of each speaker in the embodiments and comparative examples of the present invention are shown.

[0023] Explanation of reference numerals in the attached figures: 100 - Sound-generating device; 10-Outer shell; 20 - Voice-producing unit; 30 - Sound-absorbing component; 31 - Housing; 40 - Activated carbon powder; 50 - Sound-absorbing particles. Detailed Implementation

[0024] Exemplary embodiments of the invention will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the invention are shown in the drawings, it should be understood that the invention can be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided to enable a more thorough understanding of the invention and to fully convey the scope of the invention to those skilled in the art.

[0025] It should be understood that the terminology used herein is for the purpose of describing particular exemplary embodiments only and is not intended to be limiting. Unless the context clearly indicates otherwise, the singular forms “a,” “an,” and “described” as used herein may also include the plural forms. The terms “comprising,” “including,” “containing,” and “having” are inclusive and therefore indicate the presence of the stated features, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, elements, components, and / or combinations thereof. The method steps, processes, and operations described herein are not construed as requiring them to be performed in a particular order described or illustrated unless the order of performance is explicitly indicated. It should also be understood that additional or alternative steps may be used.

[0026] In the description of the embodiments of this invention, technical terms such as "first" and "second" are used only to distinguish different objects and should not be construed as indicating or implying relative importance or implicitly specifying the number, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this invention, "multiple" means two or more, unless otherwise explicitly defined.

[0027] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of the invention. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0028] In the description of the embodiments of this invention, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / " in this document generally indicates that the preceding and following related objects have an "or" relationship.

[0029] In the description of the embodiments of the present invention, the term "multiple" refers to two or more (including two), similarly, "multiple groups" refers to two or more (including two groups), and "multiple pieces" refers to two or more (including two pieces).

[0030] The first aspect of the present invention provides a sound-absorbing component, combined with Figure 1 The sound-absorbing component 30 includes a housing 31 with a receiving space, and activated carbon powder 40 and sound-absorbing particles 50 mixed and filled within the receiving space. The surface of the activated carbon powder 40 has a hydrophobic structure, the average particle size D50 of the activated carbon powder 40 is 1 μm to 50 μm, and the bulk density of the activated carbon powder 40 is 0.2 g / cm³. 3~0.6 g / cm 3 The ratio of the bulk density of activated carbon powder 40 to the bulk density of sound-absorbing particles 50 is between 0.7 and 1; the sound-absorbing particles 50 are spherical particles formed by bonding multiple molecular sieve powder particles, and the average particle size D50 of the sound-absorbing particles 50 is 200 μm to 450 μm; the shell 31 is provided with vent holes that connect to the accommodating space, and the pore size of the vent holes is smaller than the minimum particle size of activated carbon powder 40.

[0031] In an embodiment of the present invention, optionally, the sound-absorbing component 30 adopts a full-coverage structure design, that is, the outer contour of the sound-absorbing component 30 is consistent with the contour of the rear acoustic cavity, which can completely fill and fit all the spaces of the rear acoustic cavity. Activated carbon powder 40 and sound-absorbing particles 50 are mixed and filled inside the shell 31 of the sound-absorbing component 30. The activated carbon powder 40 can fill the gaps generated by the accumulation of sound-absorbing particles 50, which greatly increases the filling amount of sound-absorbing material and further improves the low-frequency acoustic performance of the sound-generating device. Moreover, the sound-absorbing material is confined and housed inside the shell 31 of the sound-absorbing component 30. Even if the sound-generating sound-absorbing particles 50 break during operation, the shell 31 can still play a good isolation role, avoiding the contamination of the sound-generating unit 20 by the broken powder, and improving the durability and service life of the sound-absorbing material.

[0032] In this embodiment of the invention, the average particle size D50 of the activated carbon powder 40 is 1 μm to 50 μm. It is understood that when the average particle size D50 of the activated carbon powder 40 is less than 1 μm, the particle size is too small, resulting in electrostatic adsorption between the particles, poor flowability, and difficulty in filling; while when the average particle size D50 of the activated carbon powder 40 is greater than 50 μm, the particle size is too large, the internal channels are too long, the efficiency of gas exchange between the particles is reduced, rapid adsorption-desorption cannot be achieved, resulting in poor acoustic performance of the sound-generating device. The average particle size D50 of activated carbon powder 40 can be one of the following: 1 μm, 2 μm, 3 μm, 4 μm, 5 μm, 6 μm, 7 μm, 8 μm, 9 μm, 10 μm, 12 μm, 15 μm, 18 μm, 20 μm, 22 μm, 25 μm, 28 μm, 30 μm, 32 μm, 35 μm, 38 μm, 40 μm, 42 μm, 45 μm, 48 μm, 50 μm, or any value within the above range.

[0033] In this embodiment of the invention, the bulk density of the activated carbon powder 40 is 0.2 g / cm³. 3 ~0.6 g / cm 3 It is understandable that if the bulk density of activated carbon powder 40 is less than 0.2 g / cm³, then... 3 At that time, the powder structure was too loose, resulting in poor mechanical stability; while if the bulk density of activated carbon powder particles 40 was greater than 0.6 g / cm³, the powder structure was too loose.3 If the particle density is too high, the pores are severely compressed, making it difficult for air to enter and affecting acoustic performance. For example, the bulk density of activated carbon powder 40 can be 0.2 g / cm³. 3 0.3 g / cm 3 0.4 g / cm 3 0.42 g / cm 3 0.5 g / cm 3 0.6 g / cm 3 One of the above values ​​or any value that satisfies the above range.

[0034] In this embodiment of the invention, the ratio of the bulk density of activated carbon powder 40 to the bulk density of sound-absorbing particles 50 is between 0.7 and 1. It is understood that when the bulk densities of activated carbon powder 40 and sound-absorbing particles 50 are similar, they are less prone to stratification after mixing. However, if the bulk densities of activated carbon powder 40 and sound-absorbing particles 50 differ significantly, under dynamic operating conditions, due to the density difference, stratification is easily driven by the density difference, leading to the agglomeration and dense packing of activated carbon powder 40, hindering air from entering the molecular sieve channels, and thus deteriorating the acoustic performance of the sound-generating device. Exemplarily, the ratio of the bulk density of activated carbon powder 40 to the bulk density of sound-absorbing particles 50 can be one of 0.7, 0.8, 0.9, or 1, or any value satisfying the above range.

[0035] In some embodiments, the hydrophobic structure of the activated carbon powder 40 includes at least one of the following: silane hydrophobic groups, fluorine-containing atom grafted groups, metal oxide hydrophobic layers, polymer coating layers, biomass hydrophobic layers, graphene layers, and carbon nanotube layers.

[0036] Specifically, the hydrophobic structure can be a silane hydrophobic group, or it can be understood as containing a silane graft group. Activated carbon can be treated with a silane coupling agent to graft alkyl hydrophobic groups onto the surface, and the resulting activated carbon powder 40 has a hydrophobic effect.

[0037] The hydrophobic structure can be a fluorine-containing graft group, and can be achieved by chemical deposition methods, such as solution impregnation deposition (dispersing activated carbon powder in an alcohol solution containing fluorine silanes, such as an ethanol-water mixture), so that a fluorine silane structure layer is formed on the surface of the activated carbon, thereby obtaining hydrophobic functionality.

[0038] The hydrophobic structure can be a hydrophobic layer of metal oxide, or it can be understood as a metal oxide coating layer. For example, in a vacuum environment, the metal oxide precursor (metal oxides such as aluminum oxide or iron oxide) is vaporized and deposited on the surface of activated carbon to form a hydrophobic layer of metal oxide, which plays a hydrophobic role.

[0039] Hydrophobic structures can be graphene layers, carbon nanotube layers, etc. For example, activated carbon can be calcined at high temperature under oxygen-free conditions to graphitize its surface structure, remove polar groups such as hydroxyl, aldehyde, and carboxyl groups, and reduce water absorption.

[0040] It is worth mentioning that, in order to balance the compatibility between the hydrophobic function of activated carbon powder 40 and the porous sound-absorbing structure, the layer thickness of the hydrophobic structure in this embodiment of the invention can be 0.01 μm to 2 μm, which does not affect the air permeability and adsorption effect and also has hydrophobicity.

[0041] In some embodiments, the volume ratio of sound-absorbing particles 50 to activated carbon powder 40 is 1:0.5 to 1. It is understood that if the proportion of sound-absorbing particles 50 is too high, there will be a large amount of unused space between the particles, resulting in wasted space; conversely, if the proportion of activated carbon powder 40 is too high, it will completely fill the pores between the sound-absorbing particles 50, causing the overall structure of the sound-absorbing component 30 to become denser, significantly increasing airflow resistance, and consequently preventing the acoustic performance of the sound-absorbing material from being fully utilized. Exemplarily, the volume ratio of sound-absorbing particles 50 to activated carbon powder 40 is one of 1:0.5, 1:0.6, 1:0.7, 1:0.8, 1:0.9, or 1:1, or any value within the above range.

[0042] In some embodiments, the activated carbon particles 40 have a pore structure with a pore size of 0.3 nm to 50 nm. It is understood that the activated carbon particles 40 may have pore structures with other pore sizes besides microporous structures with pore sizes between 0.3 nm and 1 nm, all of which have pore sizes within 50 nm. Exemplarily, the pore size of the pore structure in the activated carbon particles 40 may be one of 0.3 nm, 0.4 nm, 0.5 nm, 0.6 nm, 0.7 nm, 0.8 nm, 0.9 nm, 1 nm, 2 nm, 3 nm, 4 nm, 5 nm, 6 nm, 7 nm, 8 nm, 9 nm, 10 nm, 12 nm, 15 nm, 18 nm, 20 nm, 22 nm, 25 nm, 28 nm, 30 nm, 32 nm, 35 nm, 38 nm, 40 nm, 42 nm, 45 nm, 48 nm, or 50 nm, or any value satisfying the above range.

[0043] In embodiments of the present invention, the average particle size D50 of the sound-absorbing particles 50 is 200 μm to 450 μm. It is understood that when the average particle size D50 of the sound-absorbing particles 50 is less than 200 μm, the particle size is small, the particles are tightly packed, and the molecular sieve powder particles do not easily enter their gaps, making filling difficult; while when the average particle size D50 of the sound-absorbing particles 50 is greater than 450 μm, the particle size is large, and due to the ultra-thin design of the product, it is difficult for the particles to be arranged in the longitudinal direction of the shell 31, resulting in a reduced filling ratio of the sound-absorbing particles 50. Exemplarily, the average particle size D50 of the sound-absorbing particles 50 can be one of 200 μm, 220 μm, 250 μm, 280 μm, 300 μm, 320 μm, 350 μm, 380 μm, 400 μm, and 450 μm, or any value satisfying the above range.

[0044] In embodiments of the present invention, the sound-absorbing particles 50 are formed by bonding multiple molecular sieve powder particles with an adhesive. This results in the sound-absorbing particles 50 retaining the microporous structure of the molecular sieve powder particles, while mesopores and macropores are formed between the molecular sieve powder particles, thus creating a multi-level interconnected channel of "micropores + mesopores + macropores". This structure significantly increases the contact area between air and the molecular sieve powder particles, prolongs the residence time of air molecules within the channels, enhances the sound energy loss efficiency of the adsorption-desorption process, and achieves the effect of reducing the resonant frequency F0 of the sound-generating device.

[0045] In some embodiments, the average particle size D50 of the molecular sieve powder is 10 μm to 50 μm. It is understood that when the average particle size D50 of the molecular sieve powder is less than 10 μm, the particles produced are too small and dense, making it difficult for air to enter; while if the average particle size D50 of the molecular sieve powder is greater than 50 μm, the particles produced are too large and have low bulk strength, resulting in some wasted space. For example, the average particle size D50 of the molecular sieve powder can be one of 10 μm, 12 μm, 15 μm, 18 μm, 20 μm, 22 μm, 25 μm, 28 μm, 30 μm, 32 μm, 35 μm, 38 μm, 40 μm, 42 μm, 45 μm, 48 μm, or 50 μm, or any value satisfying the above range.

[0046] In some embodiments, the crystal structure of the molecular sieve powder includes one or more of the following crystal structures: MOR, MFI, FER, MTW, MEL, CHA, and LTL.

[0047] In some embodiments, the crystal morphology of the molecular sieve particles includes one of the following: spherical, quasi-spherical, ellipsoidal, rod-shaped, cross-shaped, blocky, polygonal, and irregular shapes.

[0048] In some embodiments, the adhesive includes at least one of organic adhesives and inorganic adhesives. For example, organic adhesives, inorganic adhesives, or a combination of organic and inorganic adhesives can be used.

[0049] Specifically, organic adhesives include one of polyacrylates, polyurethanes, and silicones. Inorganic adhesives include one of silicates, silica sols, aluminosilicates, phosphates, sulfates, and borates.

[0050] In some embodiments, the thickness of the housing 31 is 0.1 mm to 0.5 mm. It is understood that if the housing 31 is too thin, with a thickness less than 0.1 mm, the housing 31 will lack rigidity, making it prone to deformation during assembly and difficult to use; conversely, if the housing 31 is too thick, with a thickness greater than 0.5 mm, it will occupy rear cavity space and affect acoustic performance. Exemplarily, the thickness of the housing 31 can be one of 0.1 mm, 0.2 mm, 0.3 mm, 0.4 mm, or 0.5 mm, or any value within the aforementioned range.

[0051] In some embodiments, the housing 31 includes a main housing and a cover housing, which together form an accommodating space. At least one of the main housing and the cover housing is a breathable structure with vent holes. The vent holes have a pore size smaller than the minimum particle size of the activated carbon powder 40, thereby intercepting the sound-absorbing material and preventing leakage. It is understood that the main housing can be a breathable structure with vent holes, and the cover housing can be made of an impermeable or non-breathable material, i.e., the cover housing is an impermeable structure; or, the main housing can be made of an impermeable or non-breathable material, i.e., the main housing is an impermeable structure, and the cover housing is a breathable structure with vent holes; or, both the main housing and the cover housing are breathable structures with vent holes, thus allowing air or gas to enter the accommodating space of the housing 31 through the vent holes.

[0052] In some embodiments, the material of the breathable structure includes one or more of the following: woven fabric, nonwoven fabric, hot-melt mesh, open-cell polymer foam, and core-porous membrane, which can be selected according to actual needs. It is understood that at least one of the main shell and the cover shell can be an integral breathable structure made of breathable materials, such as woven fabric, nonwoven fabric, hot-melt mesh, open-cell polymer foam, core-porous membrane, etc.

[0053] In some embodiments, one of the main shell and the cover shell is formed as a non-breathable structure. The material of the non-breathable structure includes at least one film or sheet material selected from polypropylene (PP), polyethylene (PE), polycarbonate (PC), polyvinyl chloride (PVC), acrylonitrile-butadiene-styrene copolymer (ABS), and polyamide (PA). It is understood that one of the main shell and the cover shell can be entirely made of a non-breathable material, such as a film or sheet material selected from at least one of polypropylene (PP), polyethylene (PE), polycarbonate (PC), polyvinyl chloride (PVC), acrylonitrile-butadiene-styrene copolymer (ABS), and polyamide (PA). Exemplarily, the main shell can be a hot-melt plastic film made of one or more of the above-mentioned non-breathable materials, or the main shell can be a sheet material made of one or more of the above-mentioned non-breathable materials; alternatively, the cover shell can be a hot-melt plastic film made of one or more of the above-mentioned non-breathable materials, or the cover shell can be a sheet material made of one or more of the above-mentioned non-breathable materials, and the selection can be made according to actual needs.

[0054] In some embodiments, the thickness of the main housing is between 0.1 mm and 0.5 mm. Exemplarily, the thickness of the main housing may be one of 0.1 mm, 0.2 mm, 0.3 mm, 0.4 mm, 0.5 mm, or any value satisfying the above range.

[0055] In some embodiments, the thickness of the cover shell is between 0.1 mm and 0.5 mm. Exemplarily, the thickness of the cover shell can be one of 0.1 mm, 0.2 mm, 0.3 mm, 0.4 mm, 0.5 mm, or any value satisfying the above range.

[0056] In some embodiments, the air permeability of the breathable structure is 1000 mm / s to 1500 mm / s. It is understood that when the air permeability of the breathable structure is less than 1000 mm / s, the air permeability is low, reducing the efficiency of air passage and affecting the performance of the internal sound-absorbing material; while when the air permeability of the breathable structure is greater than 1500 mm / s, the air permeability is high, indicating that the size of the pores is too large or the pore structure is sparse, affecting powder interception and easily causing powder leakage. For example, the air permeability of the breathable structure can be one of 1000 mm / s, 1050 mm / s, 1100 mm / s, 1150 mm / s, 1200 mm / s, 1250 mm / s, 1300 mm / s, 1350 mm / s, 1400 mm / s, 1450 mm / s, or 1500 mm / s, or any value satisfying the above range.

[0057] It is worth mentioning that the test method for the air permeability of the breathable structure adopts GB / T 5453-1997, with a test pressure of 200 Pa and a test area of ​​20 cm². 2 .

[0058] In some embodiments, the bursting strength of the breathable structure is ≥1 N. It is understood that when the bursting strength of the breathable structure is ≥1 N, the mechanical requirements of the sound-absorbing component 30 to resist airflow impact during reliability testing and actual operating conditions can be met, ensuring that the breathable structure is not easily broken, thereby effectively preventing leakage of the internally filled sound-absorbing material. Exemplarily, the bursting strength of the breathable structure can be, but is not limited to, 1 N, 2 N, 3 N, 4 N, 5 N, 6 N, 7 N, 8 N, etc.

[0059] It is worth mentioning that the test method for the bursting strength of the breathable structure adopts GB / T 14800-9.

[0060] In some embodiments, the cover shell and the main shell are bonded together by an adhesive or hot melt bonding to obtain a shell 31 with an internal accommodating space. Exemplarily, the cover shell and the main shell can be bonded by an adhesive such as glue, adhesive film, double-sided tape, etc., or the cover shell and the main shell can be bonded by hot melt bonding.

[0061] The second aspect of the present invention provides a sound-generating device, the key feature of which is that it includes a housing 10 having an internal space and a sound-generating unit 20 disposed inside the housing 10. The sound-generating unit 20 cooperates with the housing 10 to define a front sound cavity and a rear sound cavity within the internal space of the housing 10. The sound-absorbing component 30 described in the first aspect is disposed in the rear sound cavity.

[0062] In this embodiment of the invention, the sound-absorbing component 30 is provided to confine the sound-absorbing material inside the housing 31. Therefore, even if the activated carbon powder 40 and the sound-absorbing particles 50 break during operation, they can still play a good isolation role, preventing the powder fragments from contaminating the sound-generating unit 20. At the same time, it can also improve the durability and service life of the sound-absorbing material.

[0063] A third aspect of the present invention provides an electronic device, the key feature of which is that it includes the sound-generating device 100 described in the second aspect.

[0064] In embodiments of the present invention, the electronic device may be, but is not limited to, a mobile phone, tablet computer, smartwatch, game console, learning machine, etc., and the electronic device has the characteristic of good acoustic performance. Unless otherwise defined, the technical terms used in the following embodiments have the same meaning as commonly understood by those skilled in the art. Unless otherwise specified, the experimental reagents used in the following embodiments are all conventional biochemical reagents; the raw materials, instruments, and equipment used in the following embodiments can all be obtained through commercial purchase or by existing methods; the amounts of experimental reagents used, unless otherwise specified, are the amounts used in conventional experimental operations; the experimental methods used, unless otherwise specified, are conventional methods. It should be further noted that the following description is merely exemplary and not a specific limitation of the present invention. Moreover, the selection of the following comparative examples is for comparison with the technical solutions of the present invention to demonstrate the advancement of the technical solutions of the present invention, and does not mean that the comparative examples are necessarily prior art in this technical field.

[0065] It should be noted that the module structure dimensions of each speaker (sound-emitting device 100) in the embodiments and comparative examples are consistent.

[0066] Example 1 See Figure 1 As shown, the sound-absorbing component 30 includes a shell 31 with a receiving space and activated carbon powder 40 and sound-absorbing particles 50 mixed and filled in the receiving space, wherein: the activated carbon powder 40 is selected from silanized modified activated carbon, with an average particle size D50 of 5 μm and a bulk density of 0.42 g / cm³. 3 The sound-absorbing particles 50 are spherical particles formed by bonding multiple molecular sieve powder particles (MFI crystal structure, average particle size D50 of 15 μm) with acrylic adhesive. The average particle size D50 of the sound-absorbing particles 50 is 250 μm, and the bulk density is 0.45 g / cm³. 3 The filling volume ratio of sound-absorbing particles 50 to activated carbon powder 40 is 1:0.6. The total filling volume of sound-absorbing particles 50 and activated carbon powder 40 is 0.4 mL.

[0067] The shell 31 includes a main shell and a cover shell. The main shell and the cover shell together form an accommodating space. The thickness of the main shell is 0.2 mm. The main shell is made of non-woven fabric and is thermoformed into the required shape. The cover shell is made of non-woven fabric with a thickness of 0.2 mm (breathable structure). The air permeability of the non-woven fabric is 1000 mm / s, and the bursting strength is 8 N. The main shell and the cover shell are bonded together with an adhesive film.

[0068] After the sound-absorbing component 30 is installed into the acoustic cavity of the module, the manufacturing process is complete.

[0069] Comparative Example 1 The sound-absorbing component 30 uses the same housing 31 as in Example 1. The only difference between Comparative Example 1 and Example 1 is that the accommodating space of Comparative Example 1 is filled only with sound-absorbing particles 50. The filling volume and the particle size of the sound-absorbing particles 50 are the same as in Example 1. That is, the sound-absorbing particles 50 are spherical particles formed by bonding multiple molecular sieve powder particles (MFI crystal structure, average particle size D50 of 15 μm) with acrylic adhesive. The average particle size D50 of the sound-absorbing particles 50 is 250 μm, and the bulk density is 0.45 g / cm³. 3 .

[0070] After the sound-absorbing component 30 is installed into the acoustic cavity of the module, the manufacturing process is complete.

[0071] Comparative Example 2 Without the sound-absorbing component 30, sound-absorbing particles 50 with the same filling volume and particle size as in Example 1 are directly filled into the rear acoustic cavity of the module.

[0072] Performance testing (1) Acoustic performance evaluation Impedance (IMP) tests were performed on each group of speakers in the examples and comparative examples using SoundCheck software, and the resonant frequency F0 of each speaker was measured. The test results are shown in Table 1 below.

[0073] Table 1

[0074] As can be seen from the test results in Table 1, before the sound-absorbing material was filled, the resonant frequencies F0 of the speakers in the embodiment and the comparative example were close; after the sound-absorbing material was filled, the resonant frequencies F0 of the speakers in comparative example 1 and comparative example 2 were close. This shows that although the sound-absorbing particles 50 are encapsulated inside the housing 31, they do not affect the airflow, and the sound-absorbing particles 50 can give full play to their function.

[0075] In Example 1, after the sound-absorbing component 30 was installed, the resonant frequency F0 of the speaker was significantly lower than that of Comparative Example 1 and Comparative Example 2. This indicates that the mixed filling of sound-absorbing particles 50 and activated carbon powder 40 in Example 1 helps to increase the filling amount of sound-absorbing material and improve low-frequency performance. Therefore, the resonant frequency of the speaker in Example 1 is better.

[0076] (2) High temperature and high humidity power-on reliability evaluation Experimental conditions: Each speaker in the examples and comparative examples was placed in a temperature and humidity environment of 65°C and 95%RH, and a 3.5 V voltage noise signal was applied for continuous operation for 120 h.

[0077] (2-1) Acoustic performance test: The resonant frequency F0 of each loudspeaker in the example and the comparative example was tested before and after the reliability test, and the changes in acoustic performance before and after the test were compared.

[0078] (2-2) Disassembly and observation: After the reliability test, all the speakers under test were disassembled and the powder shedding and damage of the internal sound-absorbing material were observed.

[0079] The test results are detailed in Table 2 below.

[0080] Table 2

[0081] As can be seen from the test results in Table 2, after the high temperature and high humidity energizing experiment, the change in F0 in Example 1 was within 10 Hz. This indicates that the activated carbon powder 40 did not fail after the high temperature and high humidity energizing experiment and still performed its acoustic function. The change in F0 in Comparative Example 1 was also relatively small, but the change in F0 in Comparative Example 2 was relatively high.

[0082] After disassembling the products, it was observed that the sound-absorbing materials in Example 1 and Comparative Example 1 were undamaged and there was no leakage of fine powder. However, in Comparative Example 2, the particles were broken and fine powder fell off, mainly adhering to the surface of the rear acoustic cavity shell 10 and the sound-generating unit 20. This indicates that the sound-absorbing component 30 of the present invention can not only prevent the sound-absorbing material and powder from entering the sound-generating unit 20 of the speaker, but also ensure good air permeability, allowing the sound-absorbing material to better perform its function and withstand more stringent reliability conditions.

[0083] In addition, the HOHD test curves for each speaker in the embodiments and comparative examples are shown below. Figure 2 As shown.

[0084] Depend on Figure 2 It can be seen that the higher harmonic distortion of Comparative Example 2 is relatively high, mainly because the sound-absorbing particles break and leak into the sound-generating unit 20, affecting the vibration of the voice coil, thus increasing its distortion and affecting the listening experience of the product.

[0085] In summary, the sound-generating device provided by the present invention can effectively prevent the sound-absorbing material from falling off and contaminating the sound-generating unit 20 while improving low-frequency performance.

[0086] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A sound-absorbing component, characterized in that, The device includes a shell with a containment space and activated carbon powder and sound-absorbing particles mixed and filled within the containment space. The surface of the activated carbon powder has a hydrophobic structure, the average particle size D50 of the activated carbon powder is 1 μm to 50 μm, and the bulk density of the activated carbon powder is 0.2 g / cm³. 3 ~0.6 g / cm 3 The ratio of the bulk density of the activated carbon powder to the bulk density of the sound-absorbing particles is between 0.7 and 1. The sound-absorbing particles are spherical particles formed by bonding multiple molecular sieve powder particles, and the average particle size D50 of the sound-absorbing particles is 200 μm to 450 μm. The shell is provided with a vent hole that connects to the receiving space, and the vent hole diameter is smaller than the minimum particle size of the activated carbon powder.

2. The sound-absorbing component as described in claim 1, characterized in that, The hydrophobic structure of the activated carbon powder particles includes at least one of the following: silane hydrophobic groups, fluorine-containing atom grafted groups, metal oxide hydrophobic layers, polymer coating layers, biomass hydrophobic layers, graphene layers, and carbon nanotube layers.

3. The sound-absorbing component as described in claim 1, characterized in that, The volume ratio of the sound-absorbing particles to the activated carbon powder is 1:0.5~1.

4. The sound-absorbing component as described in claim 1, characterized in that, The thickness of the shell is 0.1 mm to 0.5 mm.

5. The sound-absorbing component as described in claim 1, characterized in that, The housing includes a main housing and a cover housing, which together form the receiving space. At least one of the main housing and the cover housing is a breathable structure, and the breathable structure has the breathable holes.

6. The sound-absorbing component as described in claim 5, characterized in that, The air permeability of the breathable structure is 1000 mm / s to 1500 mm / s; and / or, The bursting strength of the breathable structure is ≥1 N.

7. The sound-absorbing component as described in claim 5, characterized in that, The breathable structure is made of at least one of the following materials: woven fabric, nonwoven fabric, hot melt mesh, open-cell polymer foam, and core-pore membrane.

8. The sound-absorbing component as described in claim 5, characterized in that, One of the main shell and the cover shell is a non-breathable structure, and the material of the non-breathable structure includes at least one of the following: polypropylene, polyethylene, polycarbonate, polyvinyl chloride, acrylonitrile-butadiene-styrene copolymer, and polyamide membrane or sheet material; and / or, The cover shell and the main shell are bonded together by adhesive or hot melt bonding.

9. A sound-generating device, characterized in that, It includes a housing with an internal space and a sound-emitting unit disposed inside the housing. The sound-emitting unit cooperates with the housing to define a front acoustic cavity and a rear acoustic cavity within the internal space of the housing. The sound-absorbing component according to any one of claims 1 to 8 is disposed in the rear acoustic cavity.

10. An electronic device, characterized in that, Includes the sound-generating device as described in claim 9.

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