Sound-producing module and preparation method therefor, and electronic device

Abstract

Provided in the present invention are a sound-producing module and a preparation method therefor, and an electronic device. The sound-producing module comprises a module housing, and a sound-producing unit, which fits with the module housing to define a front sound cavity and a rear sound cavity in an inner chamber, wherein a filling hole is provided in the module housing, and a plurality of cluster-shaped sound absorption materials or a whole block of sound absorption material is provided in the rear sound cavity. The constituent materials of the sound absorption material comprise a plurality of sound absorption particles and a plurality of bonding particles, wherein the constituent materials fill the rear sound cavity via the filling hole, and the module housing is heated, such that the bonding particles form adhesion layers on the surfaces thereof so as to connect the sound absorption particles or the bonding particles adjacent thereto. In the present invention, cluster-shaped sound absorption materials or a whole block of sound absorption material being formed in the module housing can reduce the movement of the sound absorption material in the rear sound cavity, can eliminate the flowing and friction of the sound absorption particles in the rear sound cavity, and can also prevent the acoustic performance from being affected by the sound absorption particles colliding and breaking into powder when the sound-producing module operates at a large amplitude and the powder then entering into the sound-producing module.

Description

Sound-generating modules and their manufacturing methods, electronic devices Technical Field

[0001] This invention belongs to the field of acoustic technology, specifically relating to a sound-generating module and its preparation method, and an electronic device having the sound-generating module. Background Technology

[0002] In recent years, with the trend of increasingly thinner and lighter electronic products, the space left for speakers is getting smaller and smaller. As miniature speaker modules become flatter, the volume of the acoustic rear cavity shrinks. To solve the problem of reduced low-frequency performance caused by the reduced space, engineers fill the rear acoustic cavity with sound-absorbing particles made of porous materials (such as activated carbon, natural zeolite powder, activated silica, porous alumina, molecular sieves, or mixtures made in specific types and proportions). By utilizing the special physical channel structure inside the porous material, the gas in the rear acoustic cavity is rapidly adsorbed and desorbed, achieving the effect of virtually increasing 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] In related technologies, the rear acoustic cavity of a loudspeaker module is filled with sound-absorbing particles, which occupy 70%-90% of the total volume of the cavity. These particles are fluid within the cavity. Under high-amplitude operating conditions, the sound-absorbing particles vibrate violently within the cavity, causing intense friction and collisions between particles or between the particles and the cavity's inner wall. This leads to the breakage of the particles, and the resulting powder enters the loudspeaker unit, causing contamination and resulting in acoustic performance failure. Summary of the Invention

[0004] One object of the present invention is to provide a sound-generating module that can at least solve the technical problem in the prior art that the sound-absorbing particles in the rear acoustic cavity are prone to breakage when the loudspeaker is operating under large amplitude conditions.

[0005] This invention also proposes a method for preparing a sound-generating module, which can prepare the aforementioned sound-generating module.

[0006] The present invention also proposes an electronic device comprising the aforementioned sound-generating module.

[0007] According to a first aspect of the present invention, a sound-generating module is provided, comprising: a module housing having an internal cavity therein; a sound-generating unit disposed within the internal cavity and cooperating with the module housing to define a front sound cavity and a rear sound cavity within the internal cavity; the module housing having a sound outlet communicating with the front sound cavity and a filling hole communicating with the rear sound cavity; the rear sound cavity having a plurality of clustered sound-absorbing materials or a single piece of sound-absorbing material; wherein the sound-absorbing material comprises a plurality of sound-absorbing particles and a plurality of adhesive particles, the constituent materials being filled into the rear sound cavity through the filling hole; the module housing being heated to cause the adhesive particles to switch from a first form to a second form; in the second form, the adhesive particles form an adhesion layer on their surface to connect with adjacent sound-absorbing particles or adhesive particles.

[0008] Optionally, each of the adhesive particles is bonded to at least two of the sound-absorbing particles.

[0009] Optionally, the adhesive particles in the first morphology are spherical, wedge-shaped, block-shaped, or irregular in shape, and / or the adhesive particles in the second morphology are spherical, filamentous, strip-shaped, mesh-like, or irregular in shape.

[0010] Optionally, the softening point of the adhesive particles is 80℃-130℃.

[0011] Optionally, the adhesive particles are thermoplastic polymer particles or thermosetting polymer particles.

[0012] Optionally, when the adhesive particles are thermoplastic polymer particles, the adhesive particles include at least one of polyurethane, polyamide, polymethyl methacrylate, polyethylene, polypropylene, polystyrene, copolyester, ethylene-vinyl acetate copolymer, random copolymer of ethylene and α-olefin, polyolefin / ethylene-acrylic acid copolymer, polycaprolactone, and polyethylene terephthalate; and / or, when the adhesive particles are thermosetting polymer particles, the adhesive particles include at least one of phenolic resin, urea-formaldehyde resin, melamine-formaldehyde resin, unsaturated polyester resin, epoxy resin, silicone resin, styrene-butadiene rubber, nitrile rubber, and ethylene-propylene rubber.

[0013] Optionally, the particle size of the adhesive particles is 20%-80% of the particle size of the sound-absorbing particles.

[0014] Optionally, the volume ratio of the adhesive particles to the sound-absorbing particles is 0.05-0.7.

[0015] Optionally, the particle size of the sound-absorbing particles is 100μm-600μm.

[0016] Optionally, the sound-absorbing particles include a plurality of porous raw powders and a binder, wherein the binder is used to bond the plurality of porous raw powders together to form the sound-absorbing particles.

[0017] Optionally, the porous raw powder includes at least one of activated carbon, natural zeolite, molecular sieve, silica aerogel, porous alumina, metal-organic framework materials, and covalent organic framework materials; and / or, the binder includes at least one of organic binders and inorganic binders.

[0018] Optionally, the porous raw powder is zeolite raw powder, wherein the particle size of the zeolite raw powder is greater than 10 μm, and / or the silicon-to-aluminum mass ratio of the zeolite raw powder is less than 200.

[0019] According to a second aspect of the present invention, a method for preparing a sound-generating module according to any of the above-described methods is provided, comprising the following steps: providing a module housing and a sound-generating unit, the sound-generating unit being disposed within the module housing and cooperating with the module housing to define a front sound cavity and a rear sound cavity, the module housing being provided with a sound outlet communicating with the front sound cavity and a filling hole communicating with the rear sound cavity; mixing sound-absorbing particles and adhesive particles having a first morphology in a solid state to obtain mixed particles; filling the mixed particles into the rear sound cavity through the filling hole and sealing the rear sound cavity; heating the module housing filled with the mixed particles, the adhesive particles switching from the first morphology to a second morphology, the adhesive particles forming an adhesion layer on their surface to connect with the adjacent sound-absorbing particles.

[0020] Optionally, the heating temperature of the module housing is 80℃-130℃, and the heating time is 10min-60min.

[0021] According to a third aspect of the present invention, an electronic device is provided, the electronic device comprising any of the sound-generating modules described above.

[0022] According to an embodiment of the present invention, a sound-generating module can input multiple sound-absorbing particles and multiple adhesive particles into the interior of the rear acoustic cavity through a filling hole. Subsequently, the module housing is heated, forming clusters or a single piece of sound-absorbing material within the housing. This reduces the movement of the sound-absorbing particles, preventing fragments from entering the module and affecting acoustic performance during large-amplitude operation. Furthermore, by controlling the number and state of the adhesive particles, some particles can adhere to the inner wall of the rear acoustic cavity after heating, further preventing movement of the sound-absorbing material within the cavity. Therefore, the sound-generating module of this embodiment, with its clustered or single piece of sound-absorbing material within the housing, reduces movement of the material within the rear acoustic cavity, eliminates flow and friction of the sound-absorbing particles, solves the technical problem of easily broken sound-absorbing particles, and prevents fragments from entering the module and affecting acoustic performance during large-amplitude operation.

[0023] Other features and advantages of the invention will become clear from the following detailed description of exemplary embodiments of the invention with reference to the accompanying drawings. Attached Figure Description

[0024] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments of the invention and, together with their description, serve to explain the principles of the invention.

[0025] Figure 1 is a schematic diagram of a clustered sound-absorbing material according to an embodiment of the present invention;

[0026] Figure 2 is a schematic diagram of a clustered sound-absorbing material according to an embodiment of the present invention;

[0027] Figure 3 is a schematic diagram of a clustered sound-absorbing material according to an embodiment of the present invention;

[0028] Figure 4 is a schematic diagram of a block-shaped sound-absorbing material according to an embodiment of the present invention;

[0029] Figure 5 is a schematic diagram of a sound-generating module according to an embodiment of the present invention.

[0030] The attached diagram shows the following components: sound-generating module 100; module housing 10; rear acoustic cavity 11; filling hole 12; sound-generating unit 20; sound-absorbing material 30; sound-absorbing particles 31; and adhesive particles 32. Detailed Implementation

[0031] Various exemplary embodiments of the present invention will now be described in detail with reference to the accompanying drawings. It should be noted that, unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps set forth in these embodiments do not limit the scope of the invention.

[0032] The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the invention or its application or use.

[0033] Techniques, methods, and equipment known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and equipment should be considered part of the specification.

[0034] In all the examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values.

[0035] It should be noted that similar labels and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be discussed further in subsequent figures.

[0036] The sound-generating module 100 according to an embodiment of the present invention will now be described in detail with reference to the accompanying drawings.

[0037] As shown in FIG5, the sound-generating module 100 according to an embodiment of the present invention includes a module housing 10 and a sound-generating unit 20.

[0038] Specifically, the module housing 10 has an internal cavity, and the sound-emitting unit 20 is disposed in the internal cavity and cooperates with the module housing 10 to define a front sound cavity and a rear sound cavity 11 within the internal cavity. The module housing 10 has a sound outlet hole communicating with the front sound cavity and a filling hole 12 communicating with the rear sound cavity 11. The rear sound cavity 11 contains multiple clusters of sound-absorbing materials 30 or a single piece of sound-absorbing material 30. As shown in Figures 1 to 4, the sound-absorbing material 30 is composed of multiple sound-absorbing particles 31 and multiple adhesive particles 32. The constituent materials are filled into the rear sound cavity 11 through the filling hole 12. The module housing 10 is heated to switch the adhesive particles 32 from a first form to a second form. In the second form, the adhesive particles 32 form an adhesion layer on their surface to connect with the adjacent sound-absorbing particles 31 or adhesive particles 32.

[0039] Optionally, the sound-generating unit 20 can be a loudspeaker unit, in which case the sound-generating module 100 can be a loudspeaker module. The sound-absorbing material 30 in this invention can be placed inside the loudspeaker module, for example, inside the rear acoustic cavity 11 of the loudspeaker module. It can adsorb and desorb airflow, thereby achieving a sound-absorbing effect, increasing the virtual volume of the rear acoustic cavity 11 of the loudspeaker module, and improving the low-frequency performance of the loudspeaker module.

[0040] In other words, the sound-generating module 100 according to an embodiment of the present invention mainly consists of a module housing 10 and a sound-generating unit 20. An internal cavity is defined within the module housing 10, and the sound-generating unit 20 is installed within the internal cavity of the module housing 10. Through the cooperation between the sound-generating unit 20 and the module housing 10, a front sound cavity and a rear sound cavity 11 can be defined within the internal cavity. Sound-absorbing material 30 is provided within the rear sound cavity 11, which can achieve a sound-absorbing effect.

[0041] The sound-absorbing material 30 can be prepared from sound-absorbing particles 31 and adhesive particles 32. The module housing 10 has a sound outlet and a filling hole 12. The sound outlet communicates with the front acoustic cavity, and the filling hole 12 communicates with the rear acoustic cavity 11. Multiple sound-absorbing particles 31 and multiple adhesive particles 32 can be filled into the rear acoustic cavity 11 through the filling hole 12. Subsequently, the module housing 10 is heated, which can form clusters or blocks of sound-absorbing material 30 within the module housing 10. Specifically, when the sound-absorbing particles 31 and adhesive particles 32 are introduced into the rear acoustic cavity 11 through the filling hole 12, the adhesive particles 32 are in a first state, at which point no adhesive layer has formed on the surface of the adhesive particles 32. When the sound-absorbing particles 31 and adhesive particles 32 are filled into the rear acoustic cavity 11, the speaker module can be heated. When heated, the adhesive particles 32 can switch from a first state to a second state. In the second state, the adhesive particles 32 form an adhesion layer on their surface to connect with adjacent sound-absorbing particles 31. Multiple sound-absorbing particles 31 and multiple adhesive particles 32 can be bonded together to form a cluster structure and / or an integral block structure. It is understood that there may also be cases where adhesive particles 32 are adjacent to each other; in the second state, two adjacent adhesive particles 32 are bonded together. In this embodiment, through the cooperation of the sound-absorbing particles 31 and adhesive particles 32, multiple clusters of sound-absorbing material 30 or a single block of sound-absorbing material 30 can be formed within the rear acoustic cavity 11. In addition, the softening point of the adhesive particles 32 is lower than the maximum tolerable temperature of the components of the speaker module such as the module housing 10 and the diaphragm in the sound-generating module 100. Therefore, heating the module housing 10 will not affect the module housing 10 itself or the internal acoustic components.

[0042] In this embodiment, one adhesive particle 32 can bond two or more sound-absorbing particles 31 to form a unit. A clustered structure can be formed by one adhesive particle 32 bonding two or more sound-absorbing particles 31, or by connecting multiple units to form a larger clustered unit. In this embodiment, since the movement of the clustered sound-absorbing material 30 within the rear acoustic cavity 11 is restricted, using a clustered sound-absorbing material 30 can also reduce or eliminate the movement of the sound-absorbing particles 31. In this embodiment, multiple adhesive particles 32 can also bond multiple sound-absorbing particles 31 to form a single piece of sound-absorbing material 30. This monolithic structure facilitates complete coverage within the rear acoustic cavity 11, making the sound-absorbing material 30 less prone to movement, thus better eliminating movement and collisions of the sound-absorbing particles 31. In addition, the sound-absorbing particles 31 and adhesive particles 32 are first filled into the rear acoustic cavity 11 through the filling hole 12, which can reduce the assembly difficulty between the module housing 10 and the sound-absorbing material 30, improve the assembly efficiency, and is suitable for controlling the volume and shape of the sound-absorbing material 30, and is conducive to forming an integrated sound-generating module 100.

[0043] Therefore, according to the embodiment of the present invention, the sound-generating module 100 can input multiple sound-absorbing particles 31 and multiple adhesive particles 32 into the interior of the rear acoustic cavity 11 through the filling hole 12. Subsequently, the module housing 10 is heated to form a cluster or a single piece of sound-absorbing material 30 inside the module housing 10. This reduces the movement of the sound-absorbing particles 31 within the rear acoustic cavity 11, thereby preventing the sound-absorbing particles 31 from colliding with and breaking off into the interior of the sound-generating module 100 when the sound-generating module 100 is operating at a large amplitude, thus affecting the acoustic performance. Moreover, by controlling the number and state of the adhesive particles 32, some of the adhesive particles 32 can be heated and bonded to the inner wall of the rear acoustic cavity 11, further preventing the sound-absorbing material 30 from moving within the rear acoustic cavity 11. As can be seen, the sound-absorbing material 30 is formed in a cluster or a whole piece in the module housing 10 of the sound-generating module 100 of the present invention. This can reduce the movement of the sound-absorbing material 30 in the rear acoustic cavity 11, eliminate the flow and friction of the sound-absorbing material 30 in the rear acoustic cavity 11, solve the technical problem that the sound-absorbing particles 31 are easy to break, and avoid the sound-absorbing particles 31 colliding and breaking into the interior of the sound-generating module 100 when the sound-generating module 100 is working with a large amplitude, thus affecting the acoustic performance.

[0044] According to one embodiment of the present invention, each adhesive particle 32 bonds at least two sound-absorbing particles 31. That is, one adhesive particle 32 can bond at least two sound-absorbing particles 31 when softened. In this embodiment of the invention, by controlling that each adhesive particle 32 bonds at least two sound-absorbing particles 31, it is beneficial to ensure the formation of a clustered or integral block-shaped sound-absorbing material 30.

[0045] According to one embodiment of the present invention, the shape of the adhesive particle 32 in the first form is spherical, wedge-shaped, block-shaped or irregular, etc. It can be seen that the adhesive particle 32 in the first form can have a variety of shapes, which can be selected according to the shape of the sound-absorbing material 30.

[0046] According to one embodiment of the present invention, the adhesive particles 32 in the second form are spherical, filamentous, strip-shaped, mesh-like, or irregular in shape. It can be seen that the adhesive particles 32 in the second form can have various shapes, and these shapes of adhesive particles 32 have a larger bonding area, which is beneficial for bonding with the sound-absorbing particles 31.

[0047] It should be noted that, depending on the product requirements, at least one of the shapes of the first and second forms of the adhesive particles 32 can be selected to improve product diversity.

[0048] In some specific embodiments of the present invention, the softening point of the adhesive particles 32 is 80℃-130℃. Since components such as the module housing 10 and diaphragm in the existing sound-generating module 100 are typically made of materials with a maximum tolerable temperature of not less than 130℃, using adhesive particles 32 with a softening point of 80℃-130℃ can prevent damage to the sound-generating module 100 due to heat. For example, in embodiments of the present invention, the softening point of the adhesive particles 32 is 80℃, 85℃, 90℃, 100℃, 110℃, or 130℃, which not only ensures that the adhesive particles 32 can bond the sound-absorbing particles 31 into clusters or blocks of sound-absorbing material 30, but also guarantees the normal sound-generating function of the sound-generating module 100.

[0049] In some specific embodiments of the present invention, the adhesive particles 32 are thermoplastic polymer particles or thermosetting polymer particles. That is, when the module housing 10 is heated, and the ambient temperature inside the acoustic cavity 11 reaches the softening point of the adhesive particles 32 composed of the above-mentioned materials, the outer layer of the adhesive particles 32 will soften and become sticky. In the embodiments of the present invention, the adhesive particles 32 are widely available, which is beneficial for reducing costs.

[0050] According to one embodiment of the present invention, when the adhesive particles 32 are thermoplastic polymer particles, the adhesive particles 32 include at least one of polyurethane (TPU), polyamide (PA), polymethyl methacrylate (PMMA), polyethylene (PE), polypropylene (PP), polystyrene (PS), copolyester (PES), ethylene-vinyl acetate copolymer (EVA), random copolymer of ethylene (POE) and α-olefin, polyolefin / ethylene acrylate copolymer (PO / EAA), polycaprolactone (PCL), and polyethylene terephthalate (PET).

[0051] When the adhesive particles 32 are thermosetting polymer particles, the adhesive particles 32 include at least one of phenolic resin (PF), urea-formaldehyde resin (UF), melamine-formaldehyde resin (MF), unsaturated polyester resin (UF), epoxy resin (EP), silicone resin (SI), styrene-butadiene rubber, nitrile rubber, and ethylene propylene rubber.

[0052] By using the aforementioned material as the adhesive particle 32, the adhesion in the second state is good, and the softening temperature can be controlled below the maximum tolerance temperature of the sound-generating module by 100°C, for example, the maximum tolerance temperature is 130°C. For example, when polyurethane (TPU) is selected as the adhesive particle 32, it has a suitable softening point of 90°C-120°C, good adhesive properties, and a certain degree of elasticity at room temperature, which can play a buffering role.

[0053] It should be noted that, depending on the product requirements, the adhesive particles 32 can be selected to be thermoplastic polymer particles and / or thermosetting polymer particles, thereby increasing product diversity.

[0054] In some specific embodiments of the present invention, the particle size of the adhesive particle 32 is 20%-80% of the particle size of the sound-absorbing particle 31. It should be noted that since the adhesive particle 32 exists in the stacking space between the sound-absorbing particles 31, if the particle size of the adhesive particle 32 is less than 20% of the particle size of the sound-absorbing particle 31, it will increase the difficulty of connecting the sound-absorbing particles 31, making it difficult to play its "bridge" role and difficult to form a clustered or blocky sound-absorbing material 30; if the particle size of the adhesive particle 32 is greater than 80% of the particle size of the sound-absorbing particle 31, it will easily affect the bonding stability and reduce the stability of the cluster structure, etc. Therefore, in this embodiment, the particle size of the adhesive particle 32 is less than or equal to 80% of the particle size of the sound-absorbing particle 31, and greater than or equal to 20% of the particle size of the sound-absorbing particle 31. For example, the particle size of the adhesive particle 32 is 20%, 30%, 40%, 50%, 60%, 70%, or 80% of the particle size of the sound-absorbing particle 31, which can effectively reduce the difficulty of forming a cluster structure and improve the stability of the formed cluster structure or block structure.

[0055] According to one embodiment of the present invention, the volume ratio of the adhesive particle 32 to the sound-absorbing particle 31 is 0.05-0.7. It should be noted that if the volume ratio of the adhesive particle 32 to the sound-absorbing particle 31 is less than 0.05, the total surface area of ​​the adhesive layer of the adhesive particle 32 is too small, and some sound-absorbing particles 31 are not bonded, making it difficult to form a clustered or blocky sound-absorbing material 30. If the volume ratio of the adhesive particle 32 to the sound-absorbing particle 31 is greater than 0.7, the proportion of the adhesive particle 32 in the rear acoustic cavity 11 is large, thereby affecting the sound absorption effect of the sound-absorbing material 30 and thus affecting the acoustic performance of the sound-generating module 100. In this embodiment, the volume ratio of the adhesive particle 32 to the sound-absorbing particle 31 is 0.05, 0.1, 0.2, 0.3, 0.4, 0.5 or 0.7, which can ensure that it is easier to form a cluster or block structure, reduce the mobility of the sound-absorbing particle 31, and ensure the sound absorption effect of the sound-absorbing material 30.

[0056] In some specific embodiments of the present invention, the particle size of the sound-absorbing particles 31 is 100μm-600μm. It should be noted that if the particle size of the sound-absorbing particles 31 is less than 100μm, the particles can easily enter the interior of the sound-generating module 100 through the permeable mesh, easily affecting the acoustic performance; if the particle size of the sound-absorbing particles 31 is greater than 600μm, this increases the difficulty of forming a cluster structure. Therefore, in this embodiment, the particle size of the sound-absorbing particles 31 is 100μm-600μm, for example, 100μm, 200μm, 300μm, 400μm, 500μm, or 600μm, which is beneficial for forming a cluster structure and can effectively prevent the sound-absorbing particles 31 from entering the interior of the sound-generating module 100, thus helping to ensure the acoustic performance of the sound-generating module 100.

[0057] According to one embodiment of the present invention, the sound-absorbing particle 31 comprises a plurality of porous raw powders and a binder, the binder being used to bond the plurality of porous raw powders together to form the sound-absorbing particle 31. The porous raw powders have a porous structure and possess sound-absorbing properties; the porous raw powders can be the unit structures constituting the sound-absorbing particle 31. Furthermore, the binder can bind the plurality of porous raw powders together, preventing dispersion between them and reducing the probability of the porous raw powders entering the sound-generating module 100. The sound-absorbing particle 31 can utilize the porous structure of the raw powders to adsorb and desorb air, thereby expanding its virtual volume.

[0058] In some specific embodiments of the present invention, the porous raw powder includes at least one of porous materials such as activated carbon, natural zeolite, molecular sieve, silica aerogel, porous alumina, metal-organic framework materials, and covalent organic framework materials; and / or, the binder includes at least one of organic binders and inorganic binders. It is evident that a variety of porous materials can be selected for the porous raw powder, and a variety of types of binders can also be used, thus improving the flexibility of material selection.

[0059] According to one embodiment of the present invention, the porous raw powder is zeolite raw powder, the particle size of the zeolite raw powder is greater than 10 μm, and / or the silicon-to-aluminum mass ratio of the zeolite raw powder is less than 200. When the particle size of the zeolite raw powder is too small, its sound absorption effect is easily affected. Furthermore, zeolite raw powder with a silicon-to-aluminum mass ratio of less than 200 has more aluminum atoms, resulting in more negative charges and increasing the polar sites in the zeolite raw powder. This leads to better bonding force when combined with the binder, enabling the sound-absorbing particles 31 to withstand vibrations of higher power intensity, significantly improving the strength of the sound-absorbing particles 31 and ensuring their acoustic performance. Moreover, when the particle size of the zeolite raw powder is greater than 10 μm and the silicon-to-aluminum mass ratio of the zeolite raw powder is less than 200, it ensures that the sound-absorbing particles 31 possess both good sound absorption effect and structural strength. Furthermore, by using zeolite with a particle size >10um as porous raw powder, the sound-absorbing particles 31 formed by zeolite and inorganic binder have more macroporous structures inside, which facilitates the entry and exit of air molecules into and out of the macroporous structures inside the sound-absorbing particles 31. This allows the zeolite inside to fully adsorb and desorb air molecules, increasing the utilization rate of the zeolite inside the sound-absorbing particles 31 and improving the acoustic performance of the sound-absorbing particles 31. Moreover, the inorganic binder will also form a pore structure after drying, which can further promote and improve the acoustic performance of the sound-absorbing particles 31.

[0060] The present invention also provides a method for preparing a sound-generating module 100, which can be used to prepare the sound-generating module 100 of any of the above embodiments. The preparation method includes the following steps:

[0061] A module housing 10 and a sound-emitting unit 20 are provided. The sound-emitting unit 20 is disposed inside the module housing 10 and cooperates with the module housing 10 to define a front sound cavity and a rear sound cavity 11. The module housing 10 is provided with a sound outlet hole communicating with the front sound cavity and a filling hole 12 communicating with the rear sound cavity 11.

[0062] The sound-absorbing particles 31 and the adhesive particles 32 having the first morphology are mixed in a solid state to obtain mixed particles.

[0063] The mixed particles are filled into the rear acoustic cavity 11 through the filling hole 12 and then the rear acoustic cavity 11 is sealed.

[0064] The module housing 10 filled with mixed particles is heated, and the adhesive particles 32 switch from the first form to the second form. An adhesive layer is formed on the surface of the adhesive particles 32 to connect with the adjacent sound-absorbing particles 31.

[0065] In other words, the method for preparing the sound-generating module 100 according to an embodiment of the present invention may include the following steps: First, the adhesive particles 32 having a first morphology and the sound-absorbing particles 31 are mixed uniformly in a certain proportion, for example, solid mixing can be used to obtain mixed particles. Then, a certain volume of the mixed particles can be filled into the rear acoustic cavity 11 through the filling hole 12, and then sealed. Subsequently, the module housing 10 together with the mixed particles is heated, for example, the module housing 10 together with the mixed particles is placed in an oven, and during the heating process, the adhesive particles 32 in the first state can be transformed into a second morphology.

[0066] Therefore, according to the method for preparing the sound-generating module 100 according to the embodiment of the present invention, the sound-absorbing particles 31 and the adhesive particles 32 are first filled into the rear acoustic cavity 11 through the filling hole 12. This not only reduces the assembly difficulty of the module shell 10 and the sound-absorbing material 30, but also makes it easier to control the volume and shape of the sound-absorbing material 30, and facilitates the formation of an integrated sound-generating module 100, thus improving assembly efficiency. Moreover, it is possible to prepare a clustered or monolithic sound-absorbing material 30 in the rear acoustic cavity 11, which not only reduces the movement of the sound-absorbing particles 31, but also prevents the sound-absorbing particles 31 from breaking off and entering the interior of the sound-generating module 100.

[0067] According to one embodiment of the present invention, the heating temperature of the module housing 10 is 80℃-130℃, and the heating time is 10min-60min. For example, the module housing 10, together with the mixed particles, can be placed in an oven at 80℃-130℃, and the baking time is controlled to be 10min-60min. It should be noted that, since most of the components such as the module housing 10 and the diaphragm in the existing sound-generating module 100 are made of materials with a maximum tolerable temperature of not less than 130℃, and by using adhesive particles 32 with a softening point of 80℃-130℃, the heating temperature of the module housing 10 is 80℃-130℃, and the heating time is 10min-60min, not only can an adhesive layer be formed on the outer layer of the adhesive particles 32, but also heat damage in the sound-generating module 100 can be avoided.

[0068] The present invention also provides an electronic device comprising the sound-emitting module 100 of any of the above embodiments. Since the sound-emitting module 100 of any of the above embodiments has good acoustic stability, the electronic device of the present invention also has the same advantages, which will not be elaborated upon here. Optionally, the electronic device can be a mobile phone, laptop computer, PAD, television, or smart wearable device, etc.

[0069] The sound-generating module 100 of the present invention will now be described in detail with reference to specific embodiments and comparative examples. It is to be understood that the following description is merely exemplary and not intended to limit the specific scope of the invention.

[0070] Example 1

[0071] 1) Using a 10mL graduated cylinder, measure 9.5mL of sound-absorbing particles 31 and 0.5mL of RH7050 polyurethane particles and place them in a 50mL beaker;

[0072] 2) Place the beaker in the HY-5 rotary shaker, set the frequency to 200 times / min, and perform solid-state mixing for 30 minutes;

[0073] 3) Using a 0.25mL funnel measuring cup, take 0.25mL of the well-mixed particles and fill it into the speaker module with a volume of 0.36mL in the rear acoustic cavity 11. The filling hole 12 is sealed with PET.

[0074] 4) Place the speaker module in an oven at 110℃ for 30 minutes;

[0075] 5) After baking, remove the speaker module and let it naturally warm to room temperature.

[0076] In Example 1, the sound-absorbing particles 31 were prepared by bonding zeolite powder with an adhesive. The particle size of the sound-absorbing particles 31 was 300μm-500μm, and the adhesive was a polyacrylate adhesive. The bonding particles 32 were selected from thermoplastic polymer particles, specifically RH7050 polyurethane particles with a softening point of 100℃. The particle size of the bonding particles 32 was 100μm-200μm, and the shape was irregular. The volume of the sound-absorbing material 30 in the rear acoustic cavity 11 of the speaker module in this example was 0.25mL, of which 0.22mL of sound-absorbing particles 31 were contained.

[0077] Example 2

[0078] 1) Using a 10mL graduated cylinder, measure 9mL of sound-absorbing particles 31 and 1mL of RH7050 polyurethane particles and place them in a 50mL beaker;

[0079] 2) Place the beaker in the HY-5 rotary shaker, set the frequency to 200 times / min, and perform solid-state mixing for 30 minutes;

[0080] 3) Using a 0.25mL funnel measuring cup, take 0.25mL of the well-mixed particles and fill it into the speaker module with a volume of 0.36mL in the rear acoustic cavity 11. The filling hole 12 is sealed with PET.

[0081] 4) Place the speaker module in an oven at 110℃ for 30 minutes;

[0082] 5) After baking, remove the speaker module and let it naturally warm to room temperature.

[0083] In Example 2, the sound-absorbing particles 31 were prepared by bonding zeolite powder with an adhesive. The particle size of the sound-absorbing particles 31 was 300μm-500μm, and the adhesive was a polyacrylate adhesive. The bonding particles 32 were selected from thermoplastic polymer particles, specifically RH7050 polyurethane particles with a softening point of 100℃. The particle size of the bonding particles 32 was 100μm-200μm, and the shape was irregular.

[0084] Example 3

[0085] 1) Using a 10mL graduated cylinder, measure 8mL of sound-absorbing particles 31 and 2mL of RH7050 polyurethane particles and place them in a 50mL beaker;

[0086] 2) Place the beaker in the HY-5 rotary shaker, set the frequency to 200 times / min, and perform solid-state mixing for 30 minutes;

[0087] 3) Using a 0.25mL funnel measuring cup, take 0.25mL of the well-mixed particles and fill it into the speaker module with a volume of 0.36mL in the rear acoustic cavity 11. The filling hole 12 is sealed with PET.

[0088] 4) Place the speaker module in an oven at 110℃ for 30 minutes;

[0089] 5) After baking, remove the speaker module and let it naturally warm to room temperature.

[0090] In Example 3, the sound-absorbing particles 31 were prepared by bonding zeolite powder particles with an adhesive. The particle size of the sound-absorbing particles 31 was 300μm-500μm, and the adhesive was a polyacrylate adhesive. The bonding particles 32 were selected from thermoplastic polymer particles, specifically RH7050 polyurethane particles, with a softening point of 100℃. The particle size of the bonding particles 32 was 100μm-200μm, and the shape was irregular.

[0091] Example 4

[0092] 1) Using a 10mL graduated cylinder, measure 7mL of sound-absorbing particles 31 and 3mL of RH7050 polyurethane particles and place them in a 50mL beaker;

[0093] 2) Place the beaker in the HY-5 rotary shaker, set the frequency to 200 times / min, and perform solid-state mixing for 30 minutes;

[0094] 3) Using a 0.25mL funnel measuring cup, take 0.25mL of the well-mixed particles and fill it into the speaker module with a volume of 0.36mL in the rear acoustic cavity 11. The filling hole 12 is sealed with PET.

[0095] 4) Place the speaker module in an oven at 110℃ for 30 minutes;

[0096] 5) After baking, remove the speaker module and let it naturally warm to room temperature.

[0097] In Example 4, the sound-absorbing particles 31 were prepared by bonding zeolite powder with an adhesive. The particle size of the sound-absorbing particles 31 was 300μm-500μm, and the adhesive was a polyacrylate adhesive. The bonding particles 32 were selected from thermoplastic polymer particles, specifically RH7050 polyurethane particles with a softening point of 100℃. The particle size of the bonding particles 32 was 100μm-200μm, and the shape was irregular.

[0098] Example 5

[0099] 1) Using a 10mL graduated cylinder, measure 9mL of sound-absorbing particles 31 and 1mL of 2123 phenolic resin particles and place them in a 50mL beaker;

[0100] 2) Place the beaker in the HY-5 rotary shaker, set the frequency to 200 times / min, and perform solid-state mixing for 30 minutes;

[0101] 3) Using a 0.25mL funnel measuring cup, take 0.25mL of the well-mixed particles and fill it into the speaker module with a volume of 0.36mL in the rear acoustic cavity 11. The filling hole 12 is sealed with PET.

[0102] 4) Place the speaker module in an oven at 120℃ for 30 minutes;

[0103] 5) After baking, remove the speaker module and let it naturally warm to room temperature.

[0104] In Example 5, the sound-absorbing particles 31 were prepared by bonding zeolite powder with an adhesive. The particle size of the sound-absorbing particles 31 was 300μm-500μm, and the adhesive was a polyacrylate adhesive. The bonding particles 32 were selected from thermosetting polymer particles, specifically 2123 phenolic resin particles, with a softening point of 115℃, a particle size of 100μm-200μm, and an irregular shape.

[0105] Comparative Example

[0106] Using a 0.25 mL funnel measuring cup, 0.22 mL of pure sound-absorbing particles were taken and filled into a 0.36 mL loudspeaker module in the rear acoustic cavity 11. The filling port was sealed with PET. In the comparative example, the pure sound-absorbing particles were prepared by bonding zeolite powder with the same binder as in Example 1. The particle size of the sound-absorbing particles in the comparative example was 300 μm-500 μm, the binder was polyacrylate adhesive, and the volume of the sound-absorbing particles was 0.22 mL. It should be noted that in the comparative example, sound-absorbing particles of the same material and volume as those in the sound-absorbing material 30 of the example were used and filled into the rear acoustic cavity of a loudspeaker module of the same model, then encapsulated in PET to form a complete loudspeaker module.

[0107] The speaker modules in all the above-described embodiments and comparative examples are identical in model. The following experiments were conducted on the embodiments and comparative examples respectively:

[0108] (1) Acoustic performance evaluation

[0109] The above six speaker modules were subjected to IMP (Impedance Measurement) tests using SoundCheck software. The resonant frequency F0 of the speaker modules was measured, and the test results are shown in Table 1 below.

[0110] Table 1

[0111] As can be seen from Table 1, for the speaker modules of the above embodiments and comparative examples, F0 can meet the daily use requirements in the range of 780±35Hz. Therefore, it can be seen that the above embodiments and comparative examples can meet the requirements of the speaker module.

[0112] (2) Drop test evaluation

[0113] Six speaker modules were assembled and fixed in a 200g drop fixture, placed in a 1m roller of a drop tester, and the rotation frequency was set to 20 times / min, with 600 drops. After the test, the structure corresponding to the rear acoustic cavity 11 was disassembled to observe whether the sound-absorbing material was broken or powder was shed. The observation results are shown in Table 2 below.

[0114] Table 2

[0115] As shown in Table 2, in Examples 1 to 5, the sound-absorbing particles 31 remained intact after the drop test, with no broken powder appearing. In contrast, in the comparative example, fine powder fell off due to friction and adhered to the surface of the housing and the sound-generating unit 20 corresponding to the rear acoustic cavity 11. This indicates that in Examples 1 to 5, the adhesive particles 32 and the sound-absorbing particles 31 cooperate with each other, with the sound-absorbing particles 31 bonding into clusters or forming an integral block structure, avoiding movement of the sound-absorbing particles 31 in the rear acoustic cavity 11 and eliminating the risk of impact and breakage of the sound-absorbing particles 31.

[0116] (3) Low-temperature BFPP test evaluation

[0117] Each speaker module was operated continuously for 24 hours at -20℃ with a voltage of 2.2V and a BFPP signal. After the experiment, the resonant frequency F0 of each speaker module was measured, and the damage to the sound-absorbing material 30 was observed after disassembly, as shown in Table 3.

[0118] Table 3

[0119] As can be seen from Table 3, after the low-temperature BFPP test, the resonant frequency F0 of the speaker modules in each group of embodiments remained almost unchanged, and the change was within 5Hz. However, the change in F0 of the speaker module in the comparative example was slightly higher, specifically 15Hz, which was worse than the performance of each group of embodiments.

[0120] Subsequently, the loudspeaker modules of each set of embodiments and comparative examples were disassembled after the experiment to observe the condition of the rear acoustic cavity 11. It can be seen that after the experiment, the sound-absorbing particles 31 of the loudspeaker modules of each set of embodiments were intact and there was no powder breakage. However, in the comparative example, fine powder fell off and adhered to the shell and the surface of the sound-generating unit 20 corresponding to the rear acoustic cavity 11 and entered the magnetic circuit, affecting some acoustic performance.

[0121] Therefore, it can be shown that the embodiments of the present invention all meet the reliability test requirements and are superior to the comparative examples.

[0122] In summary, the sound-generating module 100 according to the embodiments of the present invention not only achieves the formation of a clustered or integral sound-absorbing material 30 within the module housing 10 through the cooperation of sound-absorbing particles 31 and adhesive particles 32, thereby reducing the movement of sound-absorbing particles 31 within the rear acoustic cavity 11 and preventing the sound-absorbing particles 31 from colliding with and breaking off into the interior of the sound-generating module 100 when the sound-generating module 100 is operating at a large amplitude, thus avoiding the impact on acoustic performance, but also allows multiple sound-absorbing particles 31 and multiple adhesive particles 32 to be introduced into the interior of the rear acoustic cavity 11 through the filling hole 12. Subsequently, the module housing 10 is heated, which not only reduces the assembly difficulty of the sound-absorbing material 30 and the module housing 10 and improves assembly efficiency, but also, by controlling the number and state of the adhesive particles 32, allows some of the adhesive particles 32 to adhere to the inner wall of the rear acoustic cavity 11 after heating, further preventing the sound-absorbing material 30 from moving within the rear acoustic cavity 11.

[0123] While specific embodiments of the invention have been described in detail by way of examples, those skilled in the art should understand that the examples are for illustrative purposes only and not intended to limit the scope of the invention. Those skilled in the art should understand that modifications can be made to the above embodiments without departing from the scope and spirit of the invention. The scope of the invention is defined by the appended claims.

Claims

1. A sound-generating module, characterized in that, include: A module housing, wherein the module housing has an internal cavity; The sound-emitting unit is disposed in the internal cavity and cooperates with the module housing to define a front sound cavity and a rear sound cavity in the internal cavity. The module housing is provided with a sound outlet hole communicating with the front sound cavity and a filling hole communicating with the rear sound cavity. The rear sound cavity is provided with multiple clusters of sound-absorbing materials or a whole piece of sound-absorbing material. The sound-absorbing material comprises multiple sound-absorbing particles and multiple adhesive particles. The material is filled into the rear acoustic cavity through the filling hole. The module housing is heated to switch the adhesive particles from a first form to a second form. In the second form, the adhesive particles form an adhesion layer on their surface to connect with the adjacent sound-absorbing particles or adhesive particles.

2. The sound-generating module according to claim 1, characterized in that, Each of the adhesive particles is bonded to at least two of the sound-absorbing particles.

3. The sound-generating module according to claim 1, characterized in that, The adhesive particles in the first morphology are spherical, wedge-shaped, block-shaped, or irregular in shape, and / or the adhesive particles in the second morphology are spherical, filamentous, strip-shaped, mesh-like, or irregular in shape.

4. The sound-generating module according to claim 1, characterized in that, The softening point of the adhesive particles is 80℃-130℃.

5. The sound-generating module according to claim 1 or 4, characterized in that, The adhesive particles are thermoplastic polymer particles or thermosetting polymer particles.

6. The sound-generating module according to claim 5, characterized in that, When the adhesive particles are thermoplastic polymer particles, the adhesive particles include at least one of polyurethane, polyamide, polymethyl methacrylate, polyethylene, polypropylene, polystyrene, copolyester, ethylene-vinyl acetate copolymer, random copolymer of ethylene and α-olefin, polyolefin / ethylene-acrylic acid copolymer, polycaprolactone, and polyethylene terephthalate; and / or, When the adhesive particles are thermosetting polymer particles, the adhesive particles include at least one of phenolic resin, urea-formaldehyde resin, melamine-formaldehyde resin, unsaturated polyester resin, epoxy resin, silicone resin, styrene-butadiene rubber, nitrile rubber, and ethylene propylene rubber.

7. The sound-generating module according to claim 1, characterized in that, The particle size of the adhesive particles is 20%-80% of the particle size of the sound-absorbing particles; And / or, the volume ratio of the adhesive particles to the sound-absorbing particles is 0.05-0.

7.

8. The sound-generating module according to claim 1, characterized in that, The sound-absorbing particles have a particle size of 100μm-600μm.

9. The sound-generating module according to claim 1, characterized in that, The sound-absorbing particles comprise multiple porous raw powders and a binder, wherein the binder is used to bond the multiple porous raw powders together to form the sound-absorbing particles.

10. The sound-generating module according to claim 9, characterized in that, The porous raw powder includes at least one of activated carbon, natural zeolite, molecular sieve, silica aerogel, porous alumina, metal-organic framework materials, and covalent organic framework materials; and / or, the binder includes at least one of organic binders and inorganic binders.

11. The sound-generating module according to claim 10, characterized in that, The porous raw powder is zeolite raw powder, wherein the particle size of the zeolite raw powder is greater than 10 μm, and / or the silicon-to-aluminum mass ratio of the zeolite raw powder is less than 200.

12. A method for preparing a sound-generating module according to any one of claims 1-11, characterized in that, Includes the following steps: A module housing and a sound-emitting unit are provided. The sound-emitting unit is disposed inside the module housing and cooperates with the module housing to define a front sound cavity and a rear sound cavity. The module housing is provided with a sound outlet communicating with the front sound cavity and a filling hole communicating with the rear sound cavity. The sound-absorbing particles and the adhesive particles with the first morphology are mixed in a solid state to obtain mixed particles. The mixed particles are filled into the rear acoustic cavity through the filling hole, and the rear acoustic cavity is then sealed. The module housing filled with the mixed particles is heated, and the adhesive particles switch from the first form to the second form, forming an adhesive layer on their surface to connect with the adjacent sound-absorbing particles.

13. The method for preparing the sound-generating module according to claim 12, characterized in that, The heating temperature of the module housing is 80℃-130℃, and the heating time is 10min-60min.

14. An electronic device, characterized in that, Includes the sound-generating module according to any one of claims 1-11.

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