Sound absorption assembly, sound production device and electronic equipment

Abstract

This invention discloses a sound-absorbing component, a sound-generating device, and an electronic device, relating to the field of acoustics. The sound-absorbing component includes a shell and molecular sieve powder filled within the shell. The shell includes a main body and a capping part. The main body defines a receiving space, and the molecular sieve powder is filled within the receiving space. The capping part covers the main body to seal the receiving space. At least a portion of the main body is formed as a sound-absorbing structure, with a sound absorption coefficient >0.2. The main body is formed as a porous structure composed of stacked fiber filaments, including at least one of chemical fibers, modified chemical fibers, and natural fibers. The ratio of the pore volume of the micropores to the pore volume of the mesopores in the molecular sieve powder is >0.4, and the water absorption rate of the molecular sieve powder is less than 2%. The molecular sieve powder of this invention has a large pore distribution ratio and low water absorption rate, exhibiting good acoustic improvement performance even under high humidity conditions. Furthermore, the sound absorption coefficient of the main body >0.2 provides a sound absorption effect, thereby enhancing the overall sound absorption capacity of the sound-absorbing component.

Description

Technical Field

[0001] This invention relates to the field of acoustics, and more particularly to a sound-absorbing component, a sound-generating device, and an electronic device. Background Technology

[0002] In recent years, with the increasing trend towards thinner and lighter electronic products, the space available for speakers is becoming increasingly smaller. As miniature speaker modules become flatter, the volume of the acoustic rear cavity shrinks. To address the reduced low-frequency performance caused by this space reduction, sound-absorbing particles made of porous materials can be filled into the rear acoustic cavity. Utilizing the unique physical channel structure within the porous material, the rapid adsorption-desorption properties of the gas in the rear cavity are utilized to virtually enlarge the resonant space of the speaker's acoustic rear cavity, thereby effectively reducing the speaker's resonant frequency F0 and improving low-frequency sensitivity.

[0003] Currently, the average particle size of the sound-absorbing particles filling the rear cavity of loudspeakers is 300-400μm, and the volume of these particles accounts for up to 80% of the total volume of the rear cavity. Furthermore, these particles have gaps when stacked, failing to effectively fill the rear cavity and reducing the acoustic improvement effect. The production of these particles requires the addition of adhesives to shape them, which can clog some of the pores in the molecular sieve powder, causing further loss of acoustic performance. Moreover, the sound-absorbing particles are prone to breakage due to collisions during movement within the rear cavity, leading to powder contamination of the sound-emitting unit. Additionally, after prolonged operation or in high-humidity environments, the sound-absorbing particles in the rear cavity are highly susceptible to water absorption and failure, severely impacting their sound absorption performance. Summary of the Invention

[0004] The main objective of this invention is to provide a sound-absorbing component, a sound-generating device, and an electronic device, aiming to solve the technical problems that the sound-absorbing particles filled in the rear cavity of existing loudspeakers are easily broken and have poor acoustic improvement effects under high humidity conditions.

[0005] To achieve the above objectives, the present invention provides a sound-absorbing component, comprising a housing and molecular sieve powder filled within the housing. The housing includes a main body and a capping portion. The main body defines a receiving space, the molecular sieve powder is filled within the receiving space, and the capping portion covers the main body to seal the receiving space. At least a portion of the main body is formed as a sound-absorbing structure, the sound absorption coefficient of the main body is >0.2, the main body is formed as a porous structure composed of stacked fiber filaments, the fiber filaments include at least one of chemical fibers, modified chemical fibers, and natural fibers, the ratio of the pore volume of the internal micropores to the pore volume of the mesopores in the molecular sieve powder is >0.4, and the water absorption rate of the molecular sieve powder is less than 2%.

[0006] In one embodiment, the melting point of the fiber is greater than 100°C.

[0007] In one embodiment, the air permeability of the main body is 200-1000 mm / s.

[0008] In one embodiment, the areal density of the main body is 30-700 g / m³. 2 .

[0009] In one embodiment, the water absorption rate of the main body is less than 2%.

[0010] In one embodiment, the molecular sieve powder has a particle size greater than 0.5 μm.

[0011] In one embodiment, the volume of the molecular sieve powder occupies more than 60% of the volume of the accommodating space.

[0012] In one embodiment, the cover is made of double-sided adhesive, hot melt adhesive film, plastic film, or the same material as the main body.

[0013] In one embodiment, the main body and the cover are connected by heat fusion or adhesive bonding.

[0014] The present invention also provides a sound-generating device, including a sound-generating unit, a housing, and an internal cavity surrounded by the housing and the sound-generating unit, wherein the internal cavity is filled with a sound-absorbing component as described above.

[0015] In one embodiment, the housing includes a first housing and a second housing disposed opposite to each other, and the sound-absorbing component is sandwiched between the first housing and the second housing;

[0016] Alternatively, an adhesive layer may be provided on the inner wall of the outer casing, and the adhesive layer may be bonded to the sound-absorbing component.

[0017] The present invention also provides an electronic device, including the sound-generating device as described above.

[0018] This invention provides a sound-absorbing component, a sound-generating device, and an electronic device. The sound-absorbing component includes a housing and molecular sieve powder filled within the housing. The housing includes a main body and a capping portion. The main body defines a receiving space, and the molecular sieve powder is filled within the receiving space. The capping portion covers the main body to seal the receiving space. At least a portion of the main body is formed as a sound-absorbing structure, the sound absorption coefficient of the main body is >0.2, and the main body is formed as a porous structure composed of stacked fiber filaments. The fiber filaments include at least one of chemical fibers, modified chemical fibers, and natural fibers. The ratio of the pore volume of the internal micropores to the pore volume of the mesopores in the molecular sieve powder is >0.4, and the water absorption rate of the molecular sieve powder is less than 2%. At least a portion of the main body is formed as a sound-absorbing structure, with a sound absorption coefficient >0.2. This allows the shell of the main body to not only encapsulate the molecular sieve powder but also provide a certain sound absorption effect, thereby enhancing the overall sound absorption capacity of the sound-absorbing assembly. The porous structure of the main body allows the entry and exit of gas in the rear cavity while trapping the molecular sieve powder within the shell. The molecular sieve powder does not require adhesive to bond the sound-absorbing particles, thus solving the problem of adhesive clogging the molecular sieve channels and resulting in better acoustic performance. The micropores of the molecular sieve powder can adsorb and desorb nitrogen and oxygen molecules in the air. When the ratio of the micropore volume to the mesopore volume is >0.4, the molecular sieve powder exhibits excellent adsorption and desorption performance and better acoustic performance. Furthermore, the water absorption rate of the molecular sieve powder is less than 2%, maintaining its acoustic improvement performance under high humidity conditions and adapting to a wider range of working environments. Therefore, the sound-absorbing assembly of this invention maintains good acoustic improvement performance even under high humidity conditions. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments or related technologies of this drawing, the drawings used in the description of the embodiments or related technologies will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this drawing. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0020] Figure 1 This is a cross-sectional view of an embodiment of the sound-absorbing component involved in the present invention;

[0021] Figure 2 This is a cross-sectional view of another embodiment of the sound-absorbing component of the present invention, which employs adhesive bonding.

[0022] Figure 3 This is a cross-sectional view of an embodiment of the sound-generating device involved in the present invention;

[0023] Figure 4 This is a cross-sectional view of another embodiment of the sound-generating device involved in the present invention.

[0024] Explanation of reference numerals in the attached figures:

[0025] 100. Sound-generating device; 110. Sound-generating unit;

[0026] 120. Outer shell; 121. First shell; 122. Second shell;

[0027] 130. Sound-absorbing component; 131. Housing; 131a. Main body; 131b. Sealing part; 132. Molecular sieve powder; 133. Adhesive layer;

[0028] 140. Rear vocal cavity.

[0029] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0030] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0031] This invention provides a sound-absorbing component 130. Figure 1 This is a cross-sectional view of a sound-absorbing component according to an embodiment of the present invention, with reference to... Figure 1 The sound-absorbing component 130 includes a housing 131 and molecular sieve powder 132 filled within the housing 131. The housing 131 includes a main body portion 131a and a capping portion 131b. The main body portion 131a defines an accommodating space, and the molecular sieve powder 132 is filled within the accommodating space. The capping portion 131b covers the main body portion 131a to seal the accommodating space. At least a portion of the main body portion 131a is formed as a sound-absorbing structure. The sound absorption coefficient of the main body portion 131a is >0.2. The main body portion 131a is formed as a porous structure composed of stacked fiber filaments. The fiber filaments include at least one of chemical fibers, modified chemical fibers, and natural fibers. The ratio of the pore volume of the internal micropores to the pore volume of the mesopores in the molecular sieve powder 132 is >0.4. The water absorption rate of the molecular sieve powder 132 is less than 2%.

[0032] In this embodiment, molecular sieve powder 132 is confined within the shell 131, preventing its diffusion outside the containment space. At least a portion of the main body 131a is formed as a sound-absorbing structure, possessing sound-absorbing functionality. The sound-absorbing structure may include a porous sound-absorbing structure, a resonant sound-absorbing structure, and a special sound-absorbing structure. The porous sound-absorbing structure absorbs sound energy through the friction between sound waves and the material surface. The resonant sound-absorbing structure absorbs sound energy through resonance. The special sound-absorbing structure is suitable for specific sound-absorbing requirements. In this embodiment, the main body 131a is formed as a porous structure composed of stacked fiber filaments, which include at least one of chemical fibers, modified chemical fibers, and natural fibers. Specifically, usable chemical fibers include polypropylene fibers, viscose fibers, polyamide fibers, polyester fibers, polyacrylonitrile fibers, etc. Modified chemical fibers can be prepared by modifying the aforementioned chemical fibers such as polypropylene fibers, viscose fibers, polyamide fibers, polyester fibers, and polyacrylonitrile fibers. Natural fibers include cotton, linen, wool, silk, etc. This embodiment can use a variety of fiber types from a wide range of sources. One type of fiber can be selected according to the actual product performance requirements, or two or more types of fiber can be mixed.

[0033] In this embodiment, the sound absorption coefficient of the main body 131a is greater than 0.2, for example, 0.23, 0.25, 0.3, 0.33, 0.35, 0.4, 0.45, 0.5, etc. It is understood that the sound absorption coefficient characterizes the material's ability to absorb sound energy. The larger the sound absorption coefficient of the main body 131a, the stronger its sound absorption capacity, which can reduce sound wave reflection and resonance. Since the sound absorption coefficient of the main body 131a is greater than 0.2, it also has the function of improving the resonant frequency of the sound-generating device 100. Therefore, based on the sound absorption effect of the molecular sieve powder 132, the overall sound absorption effect of the sound-absorbing component 130 can be improved, which is beneficial to further improving the low-frequency performance of the sound-generating device 100.

[0034] In some feasible embodiments, the melting point of the fiber filament is greater than 100°C, for example, 110°C, 120°C, 130°C, 140°C, etc. It is understood that the temperature of the rear cavity of the sound-generating device 100 can reach 100°C. Selecting a fiber filament with a melting point greater than 100°C can prevent the main body 131a from melting. If the fiber filament melts, parameters such as the pore structure and air permeability of the main body 131a will be affected, leading to an impact on acoustic performance. Therefore, selecting a fiber filament with a melting point greater than 100°C helps the sound-absorbing component 130 maintain its acoustic performance without failure under high-temperature operating environments.

[0035] In some feasible embodiments, the air permeability of the main body 131a is 200-1000 mm / s, for example, 200 mm / s, 300 mm / s, 400 mm / s, 500 mm / s, 600 mm / s, 700 mm / s, 800 mm / s, 900 mm / s, 1000 mm / s, etc. It is understandable that if the air permeability is too low, the efficiency of the gas passing through the main body 131a in the rear cavity decreases, affecting the adsorption and desorption rate of the internal molecular sieve powder 132. If the air permeability is too high, it indicates that the pore size in the main body 131a is too large or the pore structure is too sparse, which can easily affect the interception of the molecular sieve powder 132, resulting in powder leakage. Controlling the air permeability of the main body 131a within a suitable range allows for the interception of the molecular sieve powder 132, while its own packed pore structure also provides certain acoustic performance.

[0036] In some feasible embodiments, the areal density of the main body 131a is 30-700 g / m³. 2 For example, 30g / m 2 50g / m 2 100g / m 2 150g / m 2 200g / m 2 250g / m 2 300g / m 2 350g / m 2 400g / m 2 450g / m 2 500g / m 2 550g / m 2 600g / m 2 650g / m 2 700g / m 2 It is understandable that if the areal density of the main body 131a is too low, its porous structure will be sparse and unable to effectively intercept the molecular sieve powder 132. Conversely, if the areal density is too high, the structure will be too dense, affecting airflow and the air adsorption / desorption function of the internal molecular sieve powder 132, and also occupying too much space in the rear cavity. Controlling the areal density of the main body 131a within a suitable range can effectively intercept the molecular sieve powder 132 and avoid adversely affecting its gas adsorption / desorption function. The areal density of the main body 131a can be further controlled between 35-100 g / m³. 2 Within a certain range, a main body 131a structure is obtained that can effectively intercept molecular sieve powder 132 and has good acoustic performance.

[0037] In some feasible embodiments, the thickness of the main body 131a is 0.1-5 mm, for example, 0.1 mm, 0.5 mm, 1 mm, 2 mm, 3 mm, 3.5 mm, 4 mm, 4.5 mm, 5 mm, etc. It is understood that if the thickness of the main body 131a is too thin, the porous structure composed of fiber filaments will be loose and unable to effectively intercept the molecular sieve powder 132; if the thickness is too thick, it will affect the airflow in and out of the main body 131a, affecting the air adsorption / desorption function of the internal molecular sieve powder 132, and occupying too much space in the rear cavity. Controlling the thickness of the main body 131a within the range of 0.1-5 mm allows for the interception of the molecular sieve powder 132 while maintaining smooth airflow in and out of the rear cavity. The thickness of the main body 131a can be further controlled within the range of 0.1-1 mm to obtain optimal air permeability.

[0038] In some feasible implementations, the water absorption rate of the main body 131a is less than 2%, for example, 0.5%, 0.7%, 1%, 1.2%, 1.5%, 1.8%, etc. The test conditions for the water absorption rate of the main body 131a are as follows: the material is placed in a sealed environment at 25°C and 100% humidity for 24 hours, and then removed and placed in an environment at 25°C and 50%-70% humidity for 20 minutes before testing. The water absorption rate is calculated as (mass after the experiment - mass before the experiment) / mass before the experiment. It is understandable that if the water absorption rate of the main body 131a shell is too high, it will affect the efficiency of air entering and exiting the shell, preventing the internal molecular sieve powder 132 from performing its acoustic improvement performance. Maintaining a water absorption rate of less than 2% for the main body 131a ensures that its acoustic improvement performance does not fail after high-temperature and high-humidity reliability testing, making it more adaptable to high-temperature and high-humidity working environments.

[0039] In this embodiment, the ratio of the pore volume of micropores to the pore volume of mesopores in the molecular sieve powder 132 is greater than 0.4, for example, 0.45, 0.5, 0.55, 0.6, 0.65, 0.7, 0.8, 1, 1.1, etc. Specifically, the pore size of micropores is smaller than that of mesopores. Micropores can adsorb and desorb nitrogen and oxygen molecules in the air. If the pore volume ratio of micropores is less than 0.4, the adsorption and desorption function of molecular sieve powder 132 for air decreases, affecting acoustic performance. Molecular sieve powder 132 with a pore distribution ratio of micropores greater than 0.4 will have better acoustic performance.

[0040] In this embodiment, the water absorption rate of the molecular sieve powder 132 is less than 2%, for example, 0.6%, 0.8%, 1%, 1.3%, 1.5%, 1.8%, etc. The test conditions for the water absorption rate of the molecular sieve powder 132 can refer to the water absorption rate test conditions of the main body 131a described above. Specifically, if the water absorption rate of the molecular sieve powder 132 is too high, it will affect the adsorption and desorption rate of the molecular sieve powder 132 to air, resulting in a loss of acoustic improvement performance. Controlling the water absorption rate of the molecular sieve powder 132 to less than 2% ensures that its acoustic improvement performance is maintained after high temperature and high humidity reliability testing, adapting to high temperature and high humidity working environments.

[0041] In some feasible implementations, the particle size of the molecular sieve powder 132 is greater than 0.5 μm, for example, 1 μm, 3 μm, 5 μm, 10 μm, 12 μm, 15 μm, etc. It is understood that if the particle size of the molecular sieve powder 132 is too small, the shell 131 would need a denser structure to effectively intercept the molecular sieve powder 132. However, a denser shell 131 would affect the air intake and exhaust rates, leading to a decrease in acoustic performance. By controlling the particle size of the molecular sieve powder 132 to be greater than 0.5 μm, the shell 131 can effectively intercept the molecular sieve powder 132. Furthermore, the particle size of the molecular sieve powder 132 can be controlled to be greater than 10 μm, increasing the number of porous structural units within a unit volume of the molecular sieve powder 132 to provide better acoustic performance.

[0042] In some feasible implementations, the volume of molecular sieve powder 132 occupies more than 60% of the volume of the accommodating space, for example, 62%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, 100%, etc. It is understood that the housing 131 needs to occupy a certain volume in the rear cavity, and the molecular sieve powder 132 is located within the accommodating space of the housing 131. If the volume of molecular sieve powder 132 occupies less than 60% of the accommodating space, the entire sound-absorbing assembly 130 occupies a certain volume but cannot provide an effective acoustic improvement effect. Therefore, the volume of molecular sieve powder 132 occupies more than 60% of the accommodating space. While occupying a certain volume, this allows for a greater quantity of molecular sieve powder 132, resulting in a greater number of pores in the molecular sieve powder 132, which is more conducive to the adsorption and desorption of gas in the rear cavity, providing a better acoustic improvement effect.

[0043] In some feasible embodiments, the capping portion 131b is made of double-sided adhesive, hot melt adhesive film, plastic film, or the same material as the main body portion. It is understood that the capping portion 131b covers the main body portion 131a, confining the molecular sieve powder 132 within the housing 131. The capping portion 131b can be made of a material with adhesive properties, such as double-sided adhesive or hot melt adhesive film, or it can be made of plastic film or the same material as the main body portion 131a. When the main body portion 131a and the capping portion 131b are made of the same material, the capping portion 131b, like the main body portion 131a, also has the function of improving the resonant frequency of the sound-generating device 100.

[0044] In some feasible embodiments, the main body 131a and the cap 131b are connected by heat fusion sealing or adhesive bonding. It is understood that the connection method between the main body 131a and the cap 131b can be selected based on their materials. For example, if the main body 131a and the cap 131b are made of the same material, heat fusion sealing is used; if the main body 131a and the cap 131b are made of different materials, and the adhesion between the two materials is insufficient, adhesive bonding is used. Figure 2 This is a cross-sectional view of the sound-absorbing component 130, which is connected by adhesive bonding, as shown below. Figure 2 As shown, the sound-absorbing component 130 includes a housing 131 and molecular sieve powder 132 filled in the housing 131. The housing 131 includes a main body 131a and a cover 131b. An adhesive layer 133 is provided between the main body 131a and the cover 131b to connect the main body 131a and the cover 131b.

[0045] In this embodiment, at least a portion of the main body 131a is formed as a sound-absorbing structure. The sound absorption coefficient of the main body 131a is >0.2, so that the main body 131a, in addition to encapsulating the molecular sieve powder 132, also has a certain sound absorption effect, which can improve the overall sound absorption capacity of the sound-absorbing component 130. The porous structure of the main body 131a allows the gas in the rear cavity to enter and exit, while intercepting the molecular sieve powder 132 in the shell 131. The molecular sieve powder 132 does not need to be bonded to the sound-absorbing particles with adhesive, thereby avoiding the blockage of the molecular sieve pores by adhesive. The molecular sieve powder 132 has better acoustic performance, which avoids some performance loss. The micropores of the molecular sieve powder 132 can adsorb and desorb nitrogen and oxygen molecules in the air. When the ratio of the pore volume of the micropores to the pore volume of the mesopores is >0.4, the adsorption and desorption performance of the molecular sieve powder 132 is excellent and the acoustic performance is better. Moreover, the water absorption rate of the molecular sieve powder 132 is less than 2%, and it can maintain its acoustic improvement performance without failure under high humidity conditions, adapting to a wider range of working environments. Therefore, the sound-absorbing component 130 of the present invention has good acoustic improvement performance even under high humidity conditions.

[0046] This invention also provides a sound-generating device 100, see reference to Figure 3 The sound-generating device 100 includes a sound-generating unit 110, a housing 120, and an internal cavity enclosed by the housing 120 and the sound-generating unit 110. The internal cavity is filled with the sound-absorbing component 130 as described above. The sound-generating unit 110 divides the housing 120 into a front acoustic cavity and a rear acoustic cavity 140, and the sound-absorbing component 130 can be filled in the rear acoustic cavity 140.

[0047] Optionally, refer to Figure 4 The outer casing 120 includes a first casing 121 and a second casing 122 disposed opposite to each other, with the sound-absorbing component 130 sandwiched between the first casing 121 and the second casing 122; or, an adhesive layer is provided on the inner wall of the outer casing 120, and the adhesive layer is bonded to the sound-absorbing component 130. Through the spatial limiting effect of the first casing 121 and the second casing 122, the sound-absorbing component 130 is confined within the cavity of the rear acoustic chamber 140 of the sound-generating device 100. Alternatively, the sound-absorbing component 130 can be attached to the inner wall of at least one side of the rear acoustic chamber 140 using an adhesive layer such as double-sided tape.

[0048] The sound-generating device 100 provided by this invention solves the technical problem that sound-absorbing particles are easily broken, leading to contamination of the sound-generating unit 110, and also solves the problem of sound-absorbing particles failing due to water absorption. Compared with the prior art, the beneficial effects of the sound-generating device 100 provided by this invention can be referred to the beneficial effects of the sound-absorbing component 130 in the above embodiments, and will not be repeated here.

[0049] This invention also provides an electronic device, which includes the sound-generating device 100 as described in the above embodiments.

[0050] In this embodiment, the electronic devices include mobile phones, laptops, tablets, VR (Virtual Reality) devices, AR (Augmented Reality) devices, TWS (True Wireless Stereo) earphones, smart speakers, smart wearable devices, etc.

[0051] Compared with the prior art, the beneficial effects of the electronic device provided in the embodiments of the present invention are the same as those of the sound-generating device 100 in the above embodiments, and will not be repeated here.

[0052] The sound-absorbing component of the present invention is described in detail below with specific embodiments and comparative examples. It is important to understand that the following description is merely exemplary and not intended to limit the scope of the invention. Furthermore, the comparative examples were chosen to demonstrate the technical advancements of the present invention, and not all technical solutions in the comparative examples are conventional technologies in this field.

[0053] Example 1

[0054] Both the main body 131a and the capping part 131b are made of a porous membrane material composed of stacked polypropylene fiber filaments. The membrane material has a sound absorption coefficient of 0.32, a thickness of 0.12 mm, an air permeability of 350 mm / s, and a water absorption rate of 0.7%. ZSM-5 molecular sieve powder was selected, with an average particle size of 12 μm, a micropore volume to mesopore volume ratio of 1.4, and a water absorption rate of 1.1%.

[0055] The preparation process of the sound-absorbing component 130 is as follows:

[0056] 1. Place the membrane material into a molding fixture made according to the shape of the rear cavity space. The internal volume of the fixture is 0.32ml. Then close the upper and lower molds.

[0057] 2. Place the tooling on the heating table of the vulcanizing machine, set the heating temperature to 130℃, the pressure to 0.1MPa, and maintain the temperature and pressure for 60 seconds.

[0058] 3. After hot pressing, remove the cooled tooling and open the mold to obtain the spatially shaped main body 131a.

[0059] 4. Fill the accommodating space of the main body 131a obtained by stamping with ZSM-5 molecular sieve powder until the accommodating space of the main body 131a is 100% filled by volume.

[0060] 5. Place the flat membrane material on the upper surface of the main body 131a filled with ZSM-5 molecular sieve powder, and then perform a second hot pressing with a flat mold at a temperature of 150℃ and a pressure of 0.1MPa for 60 seconds.

[0061] 6. After the second hot pressing is completed, the mold is opened and the packaged shell 131 is taken out to obtain the sound-absorbing component 130 containing ZSM-5 molecular sieve powder as sound-absorbing material.

[0062] 7. The sound-absorbing component 130 with a volume of 0.32 ml is filled into the speaker with a rear cavity volume of 0.4 ml, and the assembly is completed to obtain the whole speaker.

[0063] Comparative Example 1

[0064] Using a 0.32ml funnel measuring cup, take 0.32ml of ZSM-5 molecular sieve sound-absorbing particles with a particle size of 300-400μm (particles formed by bonding multiple ZSM-5 molecular sieve powders together with adhesive), fill it into a speaker with a rear cavity volume of 0.4ml, seal the filling port with PET, and assemble the entire speaker.

[0065] Comparative Example 2

[0066] Both the main body 131a and the cover 131b are made of a porous membrane material composed of stacked polypropylene fiber filaments. The membrane material has a sound absorption coefficient of 0.32, a thickness of 0.12 mm, an air permeability of 350 mm / s, and a water absorption rate of 0.7%.

[0067] The preparation process of the sound-absorbing component 130 is as follows:

[0068] 1. Place the membrane material into a molding fixture made according to the shape of the rear cavity space. The internal volume of the fixture is 0.32ml. Then close the upper and lower molds.

[0069] 2. Place the tooling on the heating table of the vulcanizing machine, set the heating temperature to 130℃, the pressure to 0.1MPa, and maintain the temperature and pressure for 60 seconds.

[0070] 3. After hot pressing, remove the cooled tooling and open the mold to obtain the spatially shaped main body 131a.

[0071] 4. Place the flat membrane material on the upper surface of the main body 131a, and then perform a second hot pressing using a flat mold at a temperature of 150℃ and a pressure of 0.1MPa for 60 seconds.

[0072] 5. After the second hot pressing is completed, the mold is opened and the encapsulated shell 131 is removed to obtain the sound-absorbing component 130.

[0073] 6. The sound-absorbing component 130 with a volume of 0.32 ml is filled into the speaker with a rear cavity volume of 0.4 ml, and the assembly is completed to obtain the whole speaker.

[0074] Comparative Example 3

[0075] Both the main body 131a and the capping part 131b are made of a porous membrane material composed of stacked polypropylene fiber filaments. The membrane material has a sound absorption coefficient of 0.32, a thickness of 0.12 mm, an air permeability of 350 mm / s, and a water absorption rate of 0.7%. ZSM-5 molecular sieve sound-absorbing particles (particles formed by bonding multiple ZSM-5 molecular sieve powders together with an adhesive) are selected, with an average particle size of 300-400 μm. The ratio of the pore volume of the micropores to the pore volume of the mesopores in the sound-absorbing particles is 1.03, and the water absorption rate is 1.9%.

[0076] The preparation process of the sound-absorbing component 130 is as follows:

[0077] 1. Place the membrane material into a molding fixture made according to the shape of the rear cavity space. The internal volume of the fixture is 0.32ml. Then close the upper and lower molds.

[0078] 2. Place the tooling on the heating table of the vulcanizing machine, set the heating temperature to 130℃, the pressure to 0.1MPa, and maintain the temperature and pressure for 60 seconds.

[0079] 3. After hot pressing, remove the cooled tooling and open the mold to obtain the spatially shaped main body 131a.

[0080] 4. Fill the accommodating space of the main body 131a obtained by stamping with ZSM-5 molecular sieve sound-absorbing particles until the accommodating space of the main body 131a is 100% filled.

[0081] 5. Place the flat membrane material on the upper surface of the main body 131a filled with ZSM-5 molecular sieve sound-absorbing particles, and then perform a second hot pressing with a flat mold at a temperature of 150℃ and a pressure of 0.1MPa for 60 seconds.

[0082] 6. After the second hot pressing is completed, the mold is opened and the packaged shell 131 is taken out to obtain the sound-absorbing component 130 containing ZSM-5 molecular sieve sound-absorbing particles as sound-absorbing material.

[0083] 7. The sound-absorbing component 130 with a volume of 0.32 ml is filled into the speaker with a rear cavity volume of 0.4 ml, and the assembly is completed to obtain the whole speaker.

[0084] It should be noted that the loudspeakers used in Example 1 and Comparative Examples 1-3 are all of the same model. Experimental tests were conducted on the loudspeakers assembled in Example 1 and Comparative Examples 1-3.

[0085] Acoustic performance evaluation

[0086] The loudspeakers assembled in Example 1 and Comparative Examples 1-3 were subjected to IMP (Impedance) tests, and the resonant frequency F0 of each loudspeaker was measured as shown in Table 1 below.

[0087] Table 1

[0088]

[0089] As can be seen from the results in Table 1, compared with Comparative Example 1, the resonant frequency F0 of the speaker in Example 1 is 23Hz lower than that in Comparative Example 1. This indicates that the acoustic performance improvement effect of the speaker in Example 1 is stronger than that of the speaker in Comparative Example 1, and it can better reduce the resonant frequency of the speaker, resulting in better bass quality. The variables between Example 1 and Comparative Example 1 include whether the housing 131 is used and the form of sound-absorbing material. Differences in the housing and sound-absorbing material can affect the reduction effect of the resonant frequency. Further analysis shows that when the sound-absorbing component 130 of Comparative Example 2 only has the housing 131 material, the speaker resonant frequency can be reduced by 11Hz, indicating that the housing 131 itself also has a certain acoustic improvement performance. Comparing Example 1 and Comparative Example 3, it can be found that the resonant frequency F0 of the speaker in Example 1 is 12Hz lower than that in Comparative Example 3. This indicates that when the housing 131 is 100% filled with the same volume, the form of filling with smaller molecular sieve powder 132 has a lower resonant frequency and better sound quality than the form of filling with larger sound-absorbing particles. This is because the average particle size of the particles in Comparative Example 3 is larger, and the accumulation of particles will create a larger gap space than the molecular sieve powder 132 filling method in Example 1, resulting in some space waste. In contrast, the gap space created by filling with molecular sieve powder 132 in Example 1 is smaller, which can increase the volume of effective sound-absorbing material in the sound-absorbing component 130, thus achieving a better effect in reducing the resonant frequency. Therefore, the sound-absorbing component 130 provided by the embodiments of the present invention, on the one hand, has a smaller particle size of molecular sieve powder 132, which can effectively fill the rear cavity volume, and on the other hand, it has an added housing 131 with acoustic improvement properties, thereby achieving a better effect in reducing the resonant frequency of the speaker and better overall acoustic improvement performance.

[0090] Reliability test: The speakers of Example 1 and Comparative Example 1 were placed in an environment of 65°C and 95% RH (humidity), and a 2.8V powder noise signal was applied to them, allowing both sets of speakers to operate continuously for 120 hours. Afterwards, the resonant frequencies of the two sets of speakers were tested. The results of the measured resonant frequencies F0 of each set of speakers after the experiment are shown in Table 2 below.

[0091] Table 2

[0092] experimental group Speaker test F0 / Hz Speaker test results F0 / Hz △F0 / Hz Example 1 505 520 15 Comparative Example 1 528 555 27

[0093] As can be seen from the results in Table 2, after the high temperature and high humidity reliability test, the change in F0 of the speaker in Example 1 was relatively small, at 15Hz, while the change in F0 of the speaker in Comparative Example 1 was larger, at 27Hz. This indicates that the sound-absorbing component 130 of the present invention can better withstand high temperature and high humidity environmental conditions. This is because the water absorption rate of both the shell 131 material and the molecular sieve powder 132 used as the sound-absorbing material in the speaker in Example 1 is less than 2%. After the high temperature and high humidity test, the shell 131 can still ensure the smooth entry and exit of gas in the rear cavity of the speaker, and the adsorption and desorption performance of the molecular sieve powder 132 is also maintained.

[0094] Drop test: The speakers from Example 1 and Comparative Example 1 were assembled in a 200g drop fixture and dropped 400 times from a height of 1m. After the experiment, the products were disassembled, and the powder contamination in the rear cavity was observed. The test results are shown in Table 3 below.

[0095] Table 3

[0096] experimental group Disassembly of the product and analysis of powder contamination in the rear cavity. Example 1 none Comparative Example 1 There is powder contamination

[0097] As can be seen from the results in Table 3, the speaker in Example 1 had no broken particles, while the speaker in Comparative Example 1 had broken particles contaminating the sound-absorbing particles. This is because the membrane material used in the housing 131 of Example 1 has a suitable thickness and air permeability. While providing certain acoustic improvement performance, it can effectively intercept the filled molecular sieve powder 132 through the encapsulation effect of the housing 131. This shows that the sound-absorbing component 130 of the present invention effectively avoids the breakage of sound-absorbing particles and is more resistant to harsh reliability conditions.

[0098] The above are merely preferred embodiments of the present invention and do not limit the scope of the patent. Any equivalent structural or procedural transformations made based on the description and drawings of the present invention, or direct or indirect applications in other related technical fields, are similarly included within the scope of patent protection of the present invention.

Claims

1. A sound-absorbing component, characterized in that, The invention comprises a shell and molecular sieve powder filled within the shell. The shell includes a main body and a capping portion. The main body defines a receiving space, in which the molecular sieve powder is filled. The capping portion covers the main body to seal the receiving space. At least a portion of the main body is formed as a sound-absorbing structure with a sound absorption coefficient >0.

2. The main body is formed as a porous structure composed of stacked fiber filaments, including at least one of chemical fibers, modified chemical fibers, and natural fibers. The ratio of the pore volume of the internal micropores to the pore volume of the mesopores in the molecular sieve powder is >0.4, and the water absorption rate of the molecular sieve powder is less than 2%.

2. The sound-absorbing component as described in claim 1, characterized in that, The melting point of the fiber is greater than 100°C.

3. The sound-absorbing component as described in claim 1, characterized in that, The air permeability of the main body is 200-1000 mm / s.

4. The sound-absorbing component as described in claim 1, characterized in that, The surface density of the main body is 30-700 g / m³. 2 .

5. The sound-absorbing component as described in claim 1, characterized in that, The thickness of the main body is 0.1-5mm.

6. The sound-absorbing component as described in claim 1, characterized in that, The water absorption rate of the main body is less than 2%.

7. The sound-absorbing component as described in claim 1, characterized in that, The molecular sieve powder has a particle size greater than 0.5 μm.

8. The sound-absorbing component as described in claim 1, characterized in that, The volume of the molecular sieve powder accounts for more than 60% of the volume of the containing space.

9. The sound-absorbing component as claimed in claim 1, characterized in that, The sealing part is made of double-sided adhesive, hot melt adhesive film, plastic film, or the same material as the main body.

10. The sound-absorbing component as claimed in claim 1, characterized in that, The main body and the cover are connected by heat fusion or adhesive bonding.

11. A sound-generating device, characterized in that, It includes a sound-emitting unit, a housing, and an internal cavity enclosed by the housing and the sound-emitting unit, wherein the internal cavity is filled with a sound-absorbing component as described in any one of claims 1 to 10.

12. The sound-generating device as claimed in claim 11, characterized in that, The outer casing includes a first casing and a second casing disposed opposite to each other, and the sound-absorbing component is sandwiched between the first casing and the second casing; Alternatively, an adhesive layer may be provided on the inner wall of the outer casing, and the adhesive layer may be bonded to the sound-absorbing component.

13. An electronic device, characterized in that, Includes the sound-generating device as described in claim 11 or 12.

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