Sound absorption assembly, sound production device and electronic equipment

Abstract

The invention discloses a sound absorption assembly, a sound production device and electronic equipment, and relates to the acoustics field, the sound absorption assembly comprises a shell and molecular sieve powder filled in the shell, the shell comprises a main body part and a sealing cover part, the main body part defines a containing space, the molecular sieve powder is filled in the containing space, the sealing cover part covers the main body part to seal the containing space, and the molecular sieve powder is filled in the containing space. At least part of the main body part forms a sound absorption structure, the sound absorption coefficient of the main body part is greater than 0.2, the main body part forms a porous structure formed by stacking cellosilk, the cellosilk comprises at least one of chemical fibers, modified chemical fibers and natural fibers, and the ratio of the pore volume of micropores to the pore volume of mesopores of the molecular sieve powder is greater than 0.4. The water absorption rate of the molecular sieve powder is less than 2%. The molecular sieve powder disclosed by the invention is relatively large in pore distribution proportion of micropores, low in water absorption rate and good in acoustic improvement performance under a high-humidity condition, the sound absorption coefficient of the main body part is greater than 0.2, the main body part has a sound absorption effect, and the overall sound absorption capability of the sound absorption assembly can be improved.

Description

Technical Field

[0001] The present invention relates to the field of acoustics, and in particular to a sound absorbing component, a sound generating device and an electronic device. Background Art

[0002] In recent years, with the trend of electronic products becoming increasingly thin and light, the space left for speakers is getting smaller and smaller. With the flattening of micro speaker modules, the volume of the acoustic back cavity is reduced. In order to solve the problem of reduced low-frequency performance of the speaker caused by reduced space, sound-absorbing particles made of porous materials can be filled into the back cavity, and the special physical channel structure inside the porous material can be used to quickly adsorb and desorb the gas in the back cavity, so as to achieve the virtual enlargement effect of the resonance space of the speaker's acoustic back cavity, thereby effectively reducing the speaker's resonance frequency F0 and improving low-frequency sensitivity.

[0003] At present, the average particle size of the sound-absorbing particles filled in the rear cavity of the speaker is 300-400μm, and the volume of the sound-absorbing particles accounts for up to about 80% of the total volume of the rear cavity. When these sound-absorbing particles are piled up, there are gaps in the space, which cannot effectively fill the volume of the rear cavity, resulting in a decrease in the acoustic improvement effect. When making sound-absorbing particles, adhesives need to be added to form particles. The adhesive will block some of the pores of the molecular sieve raw powder, causing further loss of acoustic performance. In addition, the sound-absorbing particles move and collide in the rear cavity, which is prone to breakage and powder contamination of the sound-emitting monomer. Moreover, after a long period of operation or when the speaker is working in a high humidity environment, the sound-absorbing particles filled in the rear cavity are very likely to absorb water and fail, which seriously affects its sound absorption effect. Summary of the invention

[0004] The main purpose of the present 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 the existing speaker are easy to break and the acoustic improvement effect is poor under high humidity conditions.

[0005] To achieve the above-mentioned purpose, the present invention provides a sound-absorbing component, comprising a shell and a molecular sieve powder filled in the shell, the shell comprising a main body and a cover part, the main body defines a containing space, the molecular sieve powder is filled in the containing space, the cover part is covered on the main body to seal the containing space, wherein at least a portion of the main body is formed as a sound-absorbing structure, the sound absorption coefficient of the main body is greater than 0.2, the main body is formed as a porous structure formed by stacking 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 of the molecular sieve powder to the pore volume of the mesopores is greater than 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 filaments 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 surface density of the main body is 30-700 g / m 2 .

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

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

[0011] In one embodiment, the volume of the molecular sieve powder accounts for more than 60% of the volume of the containing space.

[0012] In one embodiment, the sealing portion 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 hot-melt sealing or gluing.

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

[0015] In one embodiment, the housing comprises a first shell and a second shell arranged opposite to each other, and the sound absorbing assembly is sandwiched between the first shell and the second shell;

[0016] Alternatively, an adhesive layer is provided on the inner wall of the shell, and the adhesive layer is adhesively connected to the sound absorbing component.

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

[0018] The present invention provides a sound absorbing component, a sound-generating device and an electronic device, wherein the sound absorbing component comprises a shell and molecular sieve powder filled in the shell, wherein the shell comprises a main body and a cover portion, wherein the main body defines a storage space, wherein the molecular sieve powder is filled in the storage space, and the cover portion is covered on the main body to seal the storage space, wherein at least a portion of the main body is formed as a sound absorbing structure, the sound absorption coefficient of the main body is greater than 0.2, the main body is formed as a porous structure formed by stacking 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 of the molecular sieve powder to the pore volume of the mesopores is greater than 0.4, and the water absorption rate of the molecular sieve powder is less than 2%. At least part of the main body is formed into a sound-absorbing structure, and the sound absorption coefficient of the main body is greater than 0.2, so that the shell of the main body has a certain sound-absorbing effect on the basis of playing the role of encapsulating the molecular sieve powder, and can improve the overall sound absorption capacity of the sound-absorbing component; the porous structure of the main body allows the gas in the back cavity to enter and exit, and the molecular sieve powder is intercepted in the shell. The molecular sieve powder does not need to be bonded and formed with an adhesive relative to the sound-absorbing particles, thereby solving the problem of the adhesive in the sound-absorbing particles blocking the molecular sieve pores and having 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 pore volume of the micropores to the pore volume of the mesopores is greater than 0.4, the molecular sieve powder has excellent adsorption and desorption performance and better acoustic performance; and the water absorption rate of the molecular sieve powder is less than 2%, and its acoustic improvement performance can be maintained without failure under high humidity conditions, and it is suitable for a wider range of working environments. Therefore, the sound-absorbing component of the present invention has good acoustic improvement performance even under high humidity conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions in the embodiments of the present drawings or related technologies, the drawings required for use in the embodiments or related technical descriptions will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present drawings. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying any creative work.

[0020] Figure 1 A cross-sectional view of an embodiment of a sound absorbing assembly according to the present invention;

[0021] Figure 2 A cross-sectional view of another embodiment of the sound absorbing assembly according to the present invention, which is connected by adhesive bonding;

[0022] Figure 3 It is a cross-sectional view of an embodiment of the sound-generating device according to the present invention;

[0023] Figure 4 It is a cross-sectional view of another embodiment of the sound-generating device according to the present invention.

[0024] Description of reference numerals:

[0025] 100. sound generating device; 110. sound generating unit;

[0026] 120, housing; 121, first housing; 122, second housing;

[0027] 130, sound absorbing component; 131, shell; 131a, main body; 131b, cover; 132, molecular sieve powder; 133, adhesive layer;

[0028] 140. Posterior vocal cavity.

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

[0030] In order to make the above-mentioned purposes, features and advantages of the present invention more obvious and easy to understand, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work belong to the scope of protection of the present invention.

[0031] The embodiment of the present invention provides a sound absorbing assembly 130, Figure 1 This is a cross-sectional view of a sound absorbing component according to an embodiment of the present invention, referring to Figure 1 The sound absorbing component 130 includes a shell 131 and a molecular sieve powder 132 filled in the shell 131, the shell 131 includes a main body 131a and a cover part 131b, the main body 131a defines a containing space, the molecular sieve powder 132 is filled in the containing space, and the cover part 131b is covered on the main body 131a to seal the containing space, wherein 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 greater than 0.2, the main body 131a is formed as a porous structure formed by stacking 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 of the molecular sieve powder 132 to the pore volume of the mesopores is greater than 0.4, and the water absorption rate of the molecular sieve powder 132 is less than 2%.

[0032] In this embodiment, the molecular sieve powder 132 is confined in the shell 131 to prevent the molecular sieve powder 132 from diffusing outside the accommodation space. At least part of the main body 131a is formed as a sound-absorbing structure with a sound-absorbing function. 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 the sound wave and the surface of the material. The resonant sound-absorbing structure absorbs sound energy through resonance. The special sound-absorbing structure is suitable for specific sound-absorbing needs. In this embodiment, the main body 131a is formed as a porous structure stacked by fiber filaments, and the fiber filaments include at least one of chemical fibers, modified chemical fibers, and natural fibers. Specifically, the chemical fibers that can be used include polypropylene fibers, viscose fibers, polyamide fibers, polyester fibers, polyacrylonitrile fibers, and the like. The modified chemical fibers can be prepared by modifying the above-mentioned chemical fibers such as polypropylene fibers, viscose fibers, polyamide fibers, polyester fibers, and polyacrylonitrile fibers. Natural fibers include cotton, linen, wool, silk, and the like. There are many types of fiber filaments that can be used in this embodiment, and the sources are wide. According to the actual product performance requirements, fiber filaments of one material can be selected, or fiber filaments of two or more materials can be mixed.

[0033] The sound absorption coefficient of the main body 131a of this embodiment 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 can be understood that the sound absorption coefficient can characterize the ability of a material to absorb sound energy. The larger the sound absorption coefficient of the main body 131a, the stronger its sound absorption ability is, which can reduce the reflection and resonance of sound waves. The sound absorption coefficient of the main body 131a is greater than 0.2, which has the function of improving the resonant frequency of the sound-generating device 100. Therefore, on the basis of 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 conducive to further improving the low-frequency performance of the sound-generating device 100.

[0034] In some feasible implementations, the melting point of the fiber filaments is greater than 100°C, for example, 110°C, 120°C, 130°C, 140°C, etc. It is understandable that the temperature of the rear cavity of the sound-generating device 100 can reach 100°C, and the melting point of the fiber filaments is selected to be greater than 100°C, which can prevent the main body 131a from melting. After the fiber filaments melt, the parameters such as the pore structure and air permeability of the pores of the main body 131a are affected, which will lead to the impact of acoustic performance. Therefore, the melting point of the fiber filaments is selected to be greater than 100°C, which helps the sound-absorbing component 130 maintain its acoustic performance without failure in a high-temperature working environment.

[0035] In some feasible embodiments, the air permeability of the main body 131a is 200-1000mm / s, for example, 200mm / s, 300mm / s, 400mm / s, 500mm / s, 600mm / s, 700mm / s, 800mm / s, 900mm / s, 1000mm / s, etc. It is understandable that if the air permeability is too small, the efficiency of the back cavity gas passing through the main body 131a will be reduced, affecting the adsorption and desorption rate of the internal molecular sieve powder 132. If the air permeability is too large, it means that the size of the pores in the main body 131a is too large or the pore structure is sparse, which is easy to affect the interception of the molecular sieve powder 132 and cause powder leakage. Controlling the air permeability of the main body 131a within a suitable range can not only intercept the molecular sieve powder 132, but also its own stacked pore structure can provide certain acoustic performance.

[0036] In some feasible embodiments, the surface density of the main body 131a is 30-700 g / m 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 Etc. It is understandable that if the surface density of the main body 131a is too small, its porous structure will be sparse and unable to effectively intercept the molecular sieve powder 132, while if the surface density is too large and the structure is too dense, it will affect the in and out of the airflow, affect the air adsorption and desorption function of the internal molecular sieve powder 132, and occupy too much back cavity space. Controlling the surface density of the main body 131a within a suitable range can effectively intercept the molecular sieve powder 132 and avoid adverse effects on the gas adsorption and desorption function of the molecular sieve powder 132. The surface density of the main body 131a can be further controlled to be 35-100g / m 2 to obtain a main body 131a structure that can effectively intercept the molecular sieve powder 132 and has good acoustic performance.

[0037] In some feasible embodiments, the thickness of the main body 131a is 0.1-5mm, for example, 0.1mm, 0.5mm, 1mm, 2mm, 3mm, 3.5mm, 4mm, 4.5mm, 5mm, etc. It is understandable that if the thickness of the main body 131a is too thin, the porous structure composed of the fiber filaments is loose and cannot effectively intercept the molecular sieve powder 132, and if the thickness is too thick, it will affect the airflow in and out of the main body 131a, affect the air adsorption and desorption function of the internal molecular sieve powder 132, and occupy too much back cavity space. Controlling the thickness of the main body 131a within the range of 0.1-5mm can keep the gas in and out of the back cavity smoothly while intercepting the molecular sieve powder 132. The thickness of the main body 131a can also be further controlled within the range of 0.1-1mm to obtain the best air permeability.

[0038] In some feasible embodiments, 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: place the material in a closed environment at 25°C and 100% humidity for 24 hours, take out the material after the end and place it in an environment at 25°C and 50%-70% humidity for 20 minutes before testing, water absorption rate = (mass after the experiment - mass before the experiment) / mass before the experiment. It is understandable that if the water absorption rate of the shell of the main body 131a is too high, it will affect the efficiency of air entering and exiting the shell inside and outside the main body 131a, so that the internal molecular sieve powder 132 cannot play the acoustic improvement performance. The main body 131a maintains a water absorption rate of less than 2%, which can ensure that its own acoustic improvement performance does not fail after high temperature and high humidity reliability, and is more adaptable to high temperature and high humidity working environments.

[0039] The ratio of the pore volume of the internal micropores to the pore volume of the mesopores of the molecular sieve powder 132 of this embodiment 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 the micropores is smaller than that of the mesopores, and the micropores can adsorb and desorb nitrogen and oxygen molecules in the air. If the pore volume of the micropores accounts for less than 0.4, the adsorption and desorption function of the molecular sieve powder 132 for air decreases, affecting the acoustic performance. The molecular sieve powder 132 with a pore distribution ratio of micropores greater than 0.4 will have better acoustic performance.

[0040] The water absorption rate of the molecular sieve powder 132 of this embodiment 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 test conditions for the water absorption rate of the main body 131a mentioned 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 the air and lose the acoustic improvement performance. The water absorption rate of the molecular sieve powder 132 is controlled to be less than 2%, so that its acoustic improvement performance can be maintained after high temperature and high humidity reliability, and it can adapt to the working environment of high temperature and high humidity.

[0041] In some feasible embodiments, 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 understandable that if the particle size of the molecular sieve powder 132 is too small, the shell 131 needs a denser structure to intercept the molecular sieve powder 132, and a denser shell 131 will affect the air inlet and outlet rate, resulting in a decrease in acoustic performance. If the particle size of the molecular sieve powder 132 is controlled to be greater than 0.5 μm, the shell 131 can effectively intercept the molecular sieve powder 132. The particle size of the molecular sieve powder 132 can also be further controlled to be greater than 10 μm, so as to increase the number of pore structure units in the molecular sieve powder 132 per unit volume to provide better acoustic performance.

[0042] In some feasible embodiments, the volume of the molecular sieve powder 132 accounts for a proportion of the volume of the accommodation space that is greater than 60%, for example, 62%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, 100%, etc. It is understandable that the shell 131 needs to occupy a certain volume in the back cavity, and the molecular sieve powder 132 is located in the accommodation space of the shell 131. When the volume of the molecular sieve powder 132 accounts for a proportion of the volume of the accommodation space that is less than 60%, the entire sound absorbing component 130 occupies a certain volume but cannot provide an effective acoustic improvement effect. Therefore, the volume of the molecular sieve powder 132 accounts for a proportion of the volume of the accommodation space that is greater than 60%. When occupying a certain volume, the filling amount of the molecular sieve powder 132 is greater, and the number of pores in the molecular sieve powder 132 is greater, which is more conducive to the adsorption and desorption of the gas in the back cavity, and provides a better acoustic improvement effect.

[0043] In some feasible embodiments, the cover portion 131b is a double-sided adhesive, a hot melt adhesive film, a plastic film or the same material as the main body. It is understandable that the cover portion 131b is covered on the main body 131a to confine the molecular sieve powder 132 in the shell 131. The cover portion 131b is made of a material with a certain bonding effect such as a double-sided adhesive, a hot melt adhesive film, or a plastic film or the same material as the main body 131a. When the main body 131a and the cover portion 131b are made of the same material, the cover portion 131b also has the same function as the main body 131a in improving the resonant frequency of the sound-generating device 100.

[0044] In some feasible embodiments, the main body 131a and the cover 131b are connected by hot-melt packaging or gluing. It is understandable that the connection method between the main body 131a and the cover 131b can be selected according to the materials of the two. For example, when the main body 131a and the cover 131b are made of the same material, hot-melt packaging is used. When the main body 131a and the cover 131b are made of different materials and the bonding effect between the two materials is insufficient, gluing is used. Figure 2 FIG. 1 is a cross-sectional view of a sound absorbing assembly 130 connected by adhesive bonding, as shown in FIG. Figure 2 As shown, the sound absorbing component 130 includes a shell 131 and a molecular sieve powder 132 filled in the shell 131. The shell 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 part of the main body 131a is formed into a sound-absorbing structure, and the sound absorption coefficient of the main body 131a is greater than 0.2, so that the main body 131a has a certain sound-absorbing effect on the basis of encapsulating the molecular sieve powder 132, and 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 back cavity to enter and exit, and intercepts the molecular sieve powder 132 in the shell 131. The molecular sieve powder 132 does not need to be bonded and formed with adhesives relative to the sound-absorbing particles, thereby preventing the adhesive from clogging the pores in the molecular sieve. The problem of partial performance loss caused by this has better acoustic performance; the micropores of the molecular sieve powder 132 can adsorb and desorb nitrogen and oxygen molecules in the air, and when the ratio of the pore volume of the micropores to the pore volume of the mesopores is greater than 0.4, the molecular sieve powder 132 has excellent adsorption and desorption performance and better acoustic performance; and the water absorption rate of the molecular sieve powder 132 is less than 2%, and its acoustic improvement performance can be maintained without failure under high humidity conditions, and it can adapt 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] The embodiment of the present invention further provides a sound generating device 100, referring to Figure 3 The sound device 100 includes a sound unit 110, a housing 120, and an internal cavity surrounded by the housing 120 and the sound unit 110, and the internal cavity is filled with the above-mentioned sound absorbing component 130. The sound unit 110 divides the housing 120 into a front sound cavity and a rear sound cavity 140, and the sound absorbing component 130 can be filled in the rear sound cavity 140.

[0047] Optionally, refer to Figure 4 The housing 120 includes a first housing 121 and a second housing 122 that are arranged opposite to each other, and the sound absorbing component 130 is sandwiched between the first housing 121 and the second housing 122; or, an adhesive layer is provided on the inner wall of the housing 120, and the adhesive layer is bonded and connected to the sound absorbing component 130. Through the spatial limiting effect of the first housing 121 and the second housing 122, the sound absorbing component 130 is confined in the cavity of the rear sound cavity 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 sound cavity 140 by setting an adhesive layer such as a double-sided adhesive.

[0048] The sound-generating device 100 provided by the present invention solves the technical problem that the sound-absorbing particles are easily broken, resulting in the contamination of the sound-generating unit 110, and also solves the problem that the sound-absorbing particles fail to absorb water. Compared with the prior art, the beneficial effects of the sound-generating device 100 provided by the embodiment of the present invention can refer to the beneficial effects of the sound-absorbing assembly 130 in the above embodiment, and will not be repeated here.

[0049] An embodiment of the present invention further provides an electronic device, which includes the sound-generating device 100 as described in the above embodiment.

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

[0051] Compared with the prior art, the beneficial effects of the electronic device provided by the embodiment of the present invention are the same as the beneficial effects of the sound-generating device 100 of the above embodiment, which will not be elaborated herein.

[0052] The sound absorbing assembly of the present invention is described in detail below with specific embodiments and comparative examples. It is worth noting that the following description is only exemplary and not a specific limitation of the present invention. Moreover, the comparative examples are selected to demonstrate the technical progress of the technical solution of the present invention, and not all of the technical solutions in the comparative examples are conventional technologies in the technical field.

[0053] Example 1

[0054] The main body 131a and the cover 131b are both made of a porous structure membrane material formed by stacking fiber filaments of polypropylene fibers. The sound absorption coefficient of the membrane material is 0.32, the thickness of the membrane material is 0.12mm, the air permeability of the membrane material is 350mm / s, and the water absorption rate of the membrane material is 0.7%. ZSM-5 molecular sieve powder is selected, the average particle size of the molecular sieve powder 132 is 12μm, the ratio of the pore volume of micropores to the pore volume of mesopores in the molecular sieve powder 132 is 1.4, and the water absorption rate of the molecular sieve powder 132 is 1.1%.

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

[0056] 1. Place the membrane material in a molded tooling made according to the shape of the back cavity space. The internal volume of the tooling is 0.32ml, and the upper and lower molds are closed.

[0057] 2. Place the tooling on the vulcanizer heating table, set the heating temperature to 130°C, the pressure to 0.1MPa, and keep the temperature and pressure for 60s.

[0058] 3. After the hot pressing is completed, the cooled tooling is taken out and the mold is opened to obtain the main body 131a with a spatial conformation.

[0059] 4. The accommodation space of the main body 131a obtained by punching is filled with ZSM-5 molecular sieve powder until the accommodation 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 use a flat mold to perform secondary hot pressing at a temperature of 150°C and a pressure of 0.1 MPa, and keep the temperature and pressure for 60 seconds.

[0061] 6. After the secondary 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 the sound absorbing material.

[0062] 7. The sound absorbing component 130 with a volume of 0.32 ml is loaded into the loudspeaker with a rear cavity volume of 0.4 ml, and the whole loudspeaker is obtained after the assembly is completed.

[0063] Comparative Example 1

[0064] Use a 0.32ml funnel measuring cup to 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 with an adhesive), fill them 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] The main body 131a and the cover 131b are both made of a porous structure membrane material formed by stacking polypropylene fiber filaments. The sound absorption coefficient of the membrane material is 0.32, the thickness of the membrane material is 0.12mm, the air permeability of the membrane material is 350mm / s, and the water absorption rate of the membrane material is 0.7%.

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

[0068] 1. Place the membrane material in a molded tooling made according to the shape of the back cavity space. The internal volume of the tooling is 0.32ml, and the upper and lower molds are closed.

[0069] 2. Place the tooling on the vulcanizer heating table, set the heating temperature to 130°C, the pressure to 0.1MPa, and keep the temperature and pressure for 60s.

[0070] 3. After the hot pressing is completed, the cooled tooling is taken out and the mold is opened to obtain the main body 131a with a spatial conformation.

[0071] 4. Place the flat film material on the upper surface of the main body 131a, and then use a flat mold to perform secondary hot pressing at a temperature of 150°C and a pressure of 0.1MPa, and keep the temperature and pressure for 60s.

[0072] 5. After the secondary hot pressing is completed, the mold is opened and the packaged shell 131 is taken out to obtain the sound absorbing component 130.

[0073] 6. The sound absorbing component 130 with a volume of 0.32 ml is loaded into the loudspeaker with a rear cavity volume of 0.4 ml, and the whole loudspeaker is obtained after the assembly is completed.

[0074] Comparative Example 3

[0075] The main body 131a and the cover 131b are both made of a porous structure membrane material formed by stacking fiber filaments of polypropylene fibers. The sound absorption coefficient of the membrane material is 0.32, the thickness of the membrane material is 0.12mm, the air permeability of the membrane material is 350mm / s, and the water absorption rate of the membrane material is 0.7%. ZSM-5 molecular sieve sound-absorbing particles (particles formed by bonding multiple ZSM-5 molecular sieve powders with an adhesive) are selected, with an average particle size of 300-400μm, the ratio of the pore volume of the micropores of the sound-absorbing particles to the pore volume of the mesopores 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 in a molded tooling made according to the shape of the back cavity space. The internal volume of the tooling is 0.32ml, and the upper and lower molds are closed.

[0078] 2. Place the tooling on the vulcanizer heating table, set the heating temperature to 130°C, the pressure to 0.1MPa, and keep the temperature and pressure for 60s.

[0079] 3. After the hot pressing is completed, the cooled tooling is taken out and the mold is opened to obtain the main body 131a with a spatial conformation.

[0080] 4. The accommodation space of the main body 131 a obtained by punching is filled with ZSM-5 molecular sieve sound-absorbing particles until the accommodation space of the main body 131 a is filled with 100% of its volume.

[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 use a flat mold to perform secondary hot pressing at a temperature of 150° C. and a pressure of 0.1 MPa for 60 seconds.

[0082] 6. After the secondary 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 the sound absorbing material.

[0083] 7. The sound absorbing component 130 with a volume of 0.32 ml is loaded into the loudspeaker with a rear cavity volume of 0.4 ml, and the whole loudspeaker is obtained after the assembly is completed.

[0084] It should be noted that the loudspeakers used in the above embodiment 1 and comparative examples 1-3 are all loudspeakers of the same model. Experimental tests were conducted on the loudspeakers assembled in embodiment 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 and the results are shown in Table 1 below.

[0087] Table 1

[0088]

[0089] From the results in Table 1, it can be seen that, compared with Example 1 and Comparative Example 1, the resonance frequency F0 of the speaker of Example 1 is 23Hz lower than that of Comparative Example 1, indicating that the acoustic performance improvement effect of the speaker of Example 1 is stronger than that of the speaker of Comparative Example 1, and it can better reduce the resonance frequency of the speaker and has better bass sound quality. The variables between Example 1 and Comparative Example 1 include whether to use the shell 131 and the form of the sound absorbing material. The difference between the shell and the sound absorbing material may affect the effect of reducing the resonance frequency. Further analysis shows that when the sound absorbing component 130 of the speaker of Comparative Example 2 only has the shell 131 material, the resonance frequency of the speaker can be reduced by 11Hz, indicating that the shell 131 itself also has certain acoustic improvement performance. By comparing Example 1 with Comparative Example 3, it can be found that the resonant frequency F0 of the speaker in Example 1 is 12 Hz lower than that in Comparative Example 3, indicating that under the condition of 100% filling in the same volume shell 131, the form of filling the molecular sieve powder 132 with a smaller particle size has a lower resonant frequency and better sound quality than the form of filling the sound-absorbing particles with a larger particle size. This is because the average particle size of the particles in Comparative Example 3 is larger, and when the particles are piled up, a larger gap space will be generated than the filling method of the molecular sieve powder 132 in Example 1, resulting in a certain waste of space, while the gap space generated by filling the molecular sieve powder 132 in Example 1 is smaller, which can increase the volume of the effective sound-absorbing material in the sound-absorbing component 130, so the effect of reducing the resonant frequency is better. Therefore, the sound-absorbing component 130 provided in the embodiment of the present invention, on the one hand, has a smaller particle size of the molecular sieve powder 132, which can effectively fill the volume of the back cavity, and on the other hand, increases the shell 131 that has its own acoustic improvement performance, thereby having a better effect of reducing the resonant frequency of the speaker, and the overall acoustic improvement performance is better.

[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 pink noise signal of 2.8V was introduced to make the two groups of speakers work continuously for 120 hours. Afterwards, the resonant frequencies of the two groups of speakers were tested. After the experiment, the resonant frequencies F0 of the speakers of each group were measured and the results are shown in Table 2 below.

[0091] Table 2

[0092] Experimental Group F0 / Hz before speaker test F0 / Hz after speaker experiment △F0 / Hz Example 1 505 520 15 Comparative Example 1 528 555 27

[0093] From the results in Table 2, it can be seen that after the high temperature and high humidity reliability test, the change in F0 of the speaker of Example 1 is relatively small, which is 15Hz, while the change in F0 of the speaker of Comparative Example 1 is relatively large, which is 27Hz. This shows that the sound absorbing component 130 of the present invention can better withstand the environmental conditions of high temperature and high humidity. This is because the water absorption rate of the shell 131 material and the molecular sieve powder 132 used as the sound absorbing material in the speaker of 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 the gas in the rear cavity of the speaker, and the adsorption and desorption performance of the molecular sieve powder 132 is also maintained.

[0094] Drum drop test: The speakers of Example 1 and Comparative Example 1 were assembled in a 200g drop fixture, dropped from a height of 1m, and dropped 400 times. After the test, 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 Disassemble the product and check the powder contamination in the rear cavity Example 1 none Comparative Example 1 There is powder pollution

[0097] It can be seen from the results in Table 3 that the speaker of Example 1 has no powder crushing, while the sound-absorbing particles of the speaker of Comparative Example 1 are contaminated with powder crushing. This is because the membrane material used in the shell 131 of Example 1 has a suitable thickness and air permeability. While providing certain acoustic improvement performance, the filled molecular sieve powder 132 can be effectively intercepted through the packaging effect of the shell 131. This shows that the sound-absorbing component 130 of the present invention effectively avoids the powder crushing of the sound-absorbing particles and is more resistant to harsh reliability conditions.

[0098] The above are only preferred embodiments of the present invention, and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A sound absorbing component, characterized in that: The invention comprises a shell and molecular sieve powder filled in the shell, wherein the shell comprises a main body and a cover part, the main body defines a containing space, the molecular sieve powder is filled in the containing space, and the cover part is covered on the main body to seal the containing space, wherein at least a part of the main body is formed as a sound absorbing structure, the sound absorption coefficient of the main body is greater than 0.2, the main body is formed as a porous structure formed by stacking 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 of the molecular sieve powder to the pore volume of the mesopores is greater than 0.4, and the water absorption rate of the molecular sieve powder is less than 2%.

2. The sound absorbing assembly according to claim 1, characterized in that The melting point of the fiber filaments is greater than 100°C.

3. The sound absorbing assembly according to claim 1, characterized in that: The air permeability of the main body is 200-1000 mm / s.

4. The sound absorbing assembly according to claim 1, characterized in that The surface density of the main body is 30-700g / m 2 .

5. The sound absorbing assembly according to claim 1, characterized in that: The thickness of the main body is 0.1-5 mm.

6. The sound absorbing assembly according to claim 1, characterized in that: The water absorption rate of the main body is less than 2%.

7. The sound absorbing assembly according to claim 1, characterized in that The particle size of the molecular sieve powder is greater than 0.5 μm.

8. The sound absorbing assembly according to claim 1, wherein: The volume of the molecular sieve powder accounts for more than 60% of the volume of the containing space.

9. The sound absorbing assembly according to claim 1, characterized in that: The sealing portion is made of double-sided adhesive, hot-melt adhesive film, plastic film or the same material as the main body.

10. The sound absorbing assembly according to claim 1, wherein: The main body and the cover are connected by hot-melt sealing or gluing.

11. A sound-generating device, characterized in that: The invention comprises a sound-emitting unit, a shell, and an internal cavity surrounded by the shell and the sound-emitting unit, wherein the internal cavity is filled with the sound-absorbing component according to any one of claims 1 to 10.

12. The sound generating device according to claim 11, characterized in that: The housing comprises a first shell and a second shell which are arranged opposite to each other, and the sound absorbing assembly is sandwiched between the first shell and the second shell; Alternatively, an adhesive layer is provided on the inner wall of the shell, and the adhesive layer is adhesively connected to the sound absorbing component.

13. An electronic device, characterized in that: Comprising a sound-generating device as claimed in claim 11 or 12.

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