WO2022007332A1 - Acoustic adjusting material, filling method, sound generating device and electronic device - Google Patents

Abstract

An acoustic adjusting material, a sound generating device, a filling method and an electronic device. The acoustic adjusting material comprises a expandable polyolefin filler and an acoustic improving filler. The expandable polyolefin filler is foamed under a triggered condition to form a foam buffer filler, so as to provide a buffer effect for the acoustic improving filler upon movement and collision, and the foamed volume of the expandable polyolefin filler changes with the change of temperature and/or foaming time. In this way, the risk of crushing of the acoustic improving filler is greatly reduced, and the durability and service life of the acoustic adjusting material are improved.

Description

Acoustic adjustment material, filling method, sound generating device and electronic equipment technical field

The present invention relates to the technical field of electro-acoustic conversion, and more particularly, to an acoustic adjustment material for a sound-generating device, a filling method, a sound-generating device and electronic equipment.

Background technique

A sound-generating device, such as a receiver or a speaker, usually includes a housing and a sound-generating unit accommodated in the housing. The sound-generating unit divides the cavity in the casing into a front acoustic cavity and a rear acoustic cavity. The front acoustic cavity is communicated with the sound outlet hole, and the sound waves generated by the sounding unit are radiated from the front acoustic cavity. The rear acoustic cavity is communicated with the sounding unit. The vibrating airflow on the opposite side of the sound wave can radiate into the rear acoustic cavity. The rear cavity is used to adjust the low frequency effect of the sound-generating device.

In order to better adjust the low frequency effect, sound-absorbing particles are usually filled in the rear acoustic cavity. The sound-absorbing particles can adsorb and desorb the vibrating gas, so that the low-frequency effect of the sound-emitting device is better.

However, during the working process, the sound-absorbing particles will collide with each other, resulting in fragmentation. On the one hand, crushing will generate dust, and the dust will enter the sound-emitting unit, which will cause the sound-emitting unit to work abnormally. On the other hand, the fragmentation of the sound-absorbing particles will increase the F0 of the sound-generating device, resulting in poorer low-frequency effects.

Chinese utility model patent ZL201921855579.4 discloses a filler for a loudspeaker, the filler includes an expandable filler and an acoustic filler, wherein the expandable filler can be permanently expanded from a first size to a second size when the expansion is triggered, and the acoustic filler Play a fixed role, improve the sound quality in different directions, and also reduce particle collisions to a certain extent. However, the expandable filler permanently expands from the initial first size to the fixed second size when the expansion is triggered, and the size does not change any more. Suitability of fillers.

Therefore, it is necessary to provide a new technical solution to solve the above-mentioned technical problems.

SUMMARY OF THE INVENTION

An object of the present invention is to provide a new technical solution for the acoustic adjustment material of the sound generating device.

According to a first aspect of the present invention, there is provided an acoustic adjustment material. The acoustic adjustment material includes: an expandable polyolefin filler and an acoustic improvement filler, the expandable polyolefin filler is foamed under a triggered condition to become a foam buffer filler, so as to adjust the movement of the acoustic improvement filler For buffering, the foamed volume of the expandable polyolefin filler varies with temperature and/or foaming time. Optionally, the molecular chain of the expandable polyolefin filler contains olefin links, and the molecular structures of the olefin links include -CH2-CH2-, -CH(R)-CH2- and -CH(R) At least one of -CH(R)-.

Optionally, the expandable polyolefin filler is polymerized from one or more of ethylene, propylene, butene, pentene, and hexene.

Optionally, the acoustic-improving filler is a material with acoustic properties made of one or more of activated carbon, zeolite powder, silica, porous alumina, molecular sieve, and metal-organic framework material.

Optionally, the expandable polyolefin filler is spherical, quasi-spherical, rod-like, cylindrical, square or radial.

Optionally, after foaming, the density of the expandable polyolefin filler is 0.005g/mL-0.7g/mL.

Optionally, the expandable polyolefin filler is granular, and after foaming, the physical size of the expandable polyolefin filler is 0.1 mm-25 mm.

Optionally, the expandable polyolefin filler includes a polymer polyolefin material and a blowing agent mixed together, wherein the blowing agent includes a low-boiling alkane and the like.

Optionally, the expandable polyolefin filler is triggered by at least one of thermal radiation, optical radiation, and electromagnetic radiation.

Optionally, before foaming, the expandable polyolefin filler accounts for 0.01%-35% of the total volume of the acoustic adjustment material; after foaming, the volume of the foam buffer filler accounts for 0.05% of the total volume of the acoustic adjustment material -65%.

Optionally, before foaming, the expandable polyolefin filler accounts for 0.1%-15% of the total volume of the acoustic adjustment material; after foaming, the volume of the foam buffer filler accounts for 5% of the total volume of the acoustic adjustment material -55%.

Optionally, after foaming, the foam cushioning filler formed by the expandable polyolefin filler forms cushioning for the acoustic improving filler.

Optionally, after foaming, the volume of the expandable polyolefin filler increases by 2-160 times.

Optionally, after foaming, the volume of the expandable polyolefin filler increases by 3-110 times.

Optionally, the foaming process of the expandable polyolefin filler includes a first foaming stage and a second foaming stage, the first foaming stage obtains a first foam buffer filler, and the second foaming stage to obtain a second foam cushioning padding.

Optionally, the volume of the second foam buffer filler is 1-25 times the volume of the first foam buffer filler.

According to a second aspect of the present disclosure, a sound producing device is provided. The sound-generating device includes a housing, a sound-generating unit, and the above-mentioned acoustic adjustment material. The interior of the housing forms a cavity, the cavity includes a rear sound cavity, the sound-generating unit is arranged in the cavity, and the sound-generating The monomer is communicated with the rear acoustic cavity, the rear acoustic cavity includes a filling area, and the acoustic adjustment material is arranged in the filling area.

Optionally, before foaming, the filling rate of the acoustic adjustment material in the filling area is 45%-95%.

Optionally, the expandable polyolefin filler and the acoustic-improving filler are both granular materials,

The expandable polyolefin filler and the acoustic improving filler are mixed and filled in the filling area.

Optionally, both the expandable polyolefin filler and the acoustic improving filler are bulk materials,

The expandable polyolefin filler and the acoustic improvement filler are alternately arranged; or the bulk expandable polyolefin filler and the bulk acoustic improvement filler in the same layer are distributed in an array, and the expandable polyolefin filler and Acoustic-improving filler staggered settings.

Optionally, the expandable polyolefin filler forms a lattice structure, and the acoustic improvement filler is filled in the gaps formed by the expandable polyolefin filler; or the acoustic improvement filler forms a lattice structure, the The expandable polyolefin filler is filled in the gap formed by the acoustic improving filler.

According to a third aspect of the present disclosure, there is provided a filling method of an acoustic adjustment material of a sound generating device. The acoustic adjustment material is arranged in the filling area of the rear acoustic cavity of the sound generating device in any of the following ways:

The acoustic adjustment material is granular, and the expandable polyolefin filler is first filled into the filling area, and then the acoustic improvement filler is filled into the filling area;

The acoustic adjustment material is granular, and the acoustic improvement filler is first filled into the filling area, and then the expandable polyolefin filler is filled into the filling area;

The acoustic adjustment material is granular, and the expandable polyolefin filler and the acoustic improvement filler are mixed first, and then the mixed expandable polyolefin filler and the acoustic improvement filler are filled into the filling area;

First, the expandable polyolefin filler is disposed on at least one wall of the filling area to form an expandable polyolefin filler layer, and then the acoustic improving filler is filled into the filling area.

According to a fourth aspect of the present disclosure, an electronic device is provided. The electronic device includes the above-mentioned sound generating device.

According to one embodiment of the present disclosure, the acoustic tuning material includes an expandable polyolefin filler and an acoustic improving filler. After being triggered, the foaming of the expandable polyolefin filler becomes a foamed body foam, and the foamed body foam provides a buffering effect on the flow and collision of the acoustically improved filler. During the working process of the sound-generating device, the expandable polyolefin filler greatly reduces the risk of crushing of the acoustic-improving filler, and improves the durability and service life of the acoustic-modulating material.

Other features and advantages of the present invention will become apparent from the following detailed description of exemplary embodiments of the present invention with reference to the accompanying drawings.

Description of drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention.

FIG. 1 is a schematic diagram of an unfoamed state of a granular acoustic adjustment material according to an embodiment of the present disclosure.

FIG. 2 is a schematic diagram of a foamed state of a granular acoustic adjustment material according to an embodiment of the present disclosure.

FIG. 3 is a schematic diagram of an unfoamed state of a bulk acoustic adjustment material according to an embodiment of the present disclosure.

FIG. 4 is a schematic diagram of a foamed state of a block acoustic adjustment material according to an embodiment of the present disclosure.

FIG. 5 is a schematic diagram of an unfoamed state of the bulk acoustic modulation material distributed in an array according to an embodiment of the present disclosure.

FIG. 6 is a schematic diagram of an unfilled state of the acoustic adjustment material of the grid structure according to an embodiment of the present disclosure.

Description of reference numbers:

11: shell; 12: sound-emitting monomer; 13: gap; 14: expandable polyolefin filler; 15: acoustic improvement filler; 16: rear acoustic cavity.

detailed description

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

The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the invention, its application, or uses.

Techniques, methods, and apparatus known to those of ordinary skill in the relevant art may not be discussed in detail, but where appropriate, such techniques, methods, and apparatus should be considered part of the specification.

In all examples shown and discussed herein, any specific values should be construed as illustrative only and not limiting. Accordingly, other instances of the exemplary embodiment may have different values.

It should be noted that like numerals and letters refer to like items in the following figures, so once an item is defined in one figure, it does not require further discussion in subsequent figures.

According to one embodiment of the present disclosure, there is provided an acoustic adjustment material for a sound generating device. As shown in FIGS. 1-2 , the acoustic adjustment material includes: expandable polyolefin filler 14 and acoustic improvement filler 15 . The expandable polyolefin filler 14 is foamed under the condition of being triggered to become a foam buffer filler, so as to buffer the movement of the acoustic improvement filler 15. The expandable polyolefin filler 14 is foamed. Volume varies with temperature and/or foaming time.

The degree of cushioning of the expandable polyolefin filler 14 during movement and collision can be flexibly controlled by the foaming temperature and time of the expandable polyolefin filler 14 . When the expandable polyolefin filler 14 is foamed, the temperature increases, the damping of the expandable polyolefin filler 14 is increased, and the buffer capacity of the expandable polyolefin filler 14 is enhanced. Within the set time, the higher the temperature, the larger the volume of the foam cushioning filler; under the set temperature, the longer the foaming time, the larger the volume of the foam cushioning filler.

When the sound-generating device is impacted by an external force, the foam buffer filler provides a buffer force for the flow and collision of the acoustic-improving filler, and reduces the collision rate of the acoustic-improving filler. In this way, the risk of crushing of the acoustically-improving filler is greatly reduced, and the durability and service life of the acoustically-modifying material is improved.

The expandable polyolefin filler 14 refers to a polyolefin material that can foam under a set trigger condition. Under untriggered conditions, the expandable polyolefin filler 14 has a smaller volume. This enables the material to be easily filled into a given cavity (eg, the filling area of the rear acoustic cavity). The material foams under triggered conditions, providing cushioning when the acoustically-improving filler collides.

The molecular chain of the expandable polyolefin filler contains olefin links, and the molecular structures of the olefin links include -CH2-CH2-, -CH(R)-CH2- and -CH(R)-CH(R )- at least one in which R is an alkyl group. For example, the expandable polyolefin filler is obtained by polymerizing one or more of ethylene, propylene, butene, pentene, and hexene. All of the above materials can be triggered by thermal radiation to foam. Moreover, at different trigger temperatures, the volume after foaming is different, and the volume will change with the temperature change during the application process.

The acoustic-improving filler 15 refers to a porous material capable of adsorbing and desorbing vibrating gas. For example, acoustic adjustment materials include acoustic performance materials made of one or more of activated carbon, zeolite powder, silica, porous alumina, molecular sieves, metal-organic framework materials, and the like. The acoustic improving filler 15 may be in the form of granules, flakes, blocks, and the like.

Optionally, the expandable polyolefin filler is spherical, quasi-spherical, rod-shaped, cylindrical, square or radial. The above shape has good filling effect and high filling rate.

In the embodiment of the present disclosure, the acoustic adjustment material includes the expandable polyolefin filler 14 and the acoustic improvement filler 15 . The expandable polyolefin filler 14 is foamed under the triggering condition to become a foam buffer filler, so as to buffer the movement of the acoustic improvement filler 15 . During the working process of the sound-generating device, the acoustic-improving filler 15 is less likely to collide. In this way, the expandable polyolefin filler 14 greatly reduces the risk of breakage of the acoustic improvement filler 15 and increases the durability and service life of the acoustic adjustment material.

In addition, after the expandable polyolefin filler 14 is foamed, cells are formed. The expandable polyolefin material has elasticity, and the cells can change the volume according to the change of the external pressure, so as to form a buffering effect on the movement of the acoustic improvement filler 15 . In this way, the expandable polyolefin filler 14 can effectively buffer the flow and collision of the acoustic improvement filler 15 .

In particular, the expandable polyolefin filler 14 can effectively buffer the vibration of the acoustic adjustment material when the sound-generating device operates at high power.

In addition, when the sound generating device is impacted by external force, the cells provide buffer force for the acoustic improvement filler 15, and the gas in the cells is stagnant and compressed, so that the external energy is consumed and dissipated. The cells gradually terminate the impact load with a small negative acceleration, so the expandable polyolefin filler 14 has a good shockproof effect.

In addition, the different triggering temperatures enable the expandable polyolefin filler 14 to change the volume of foaming, thereby adapting to different application environments, which makes the acoustic adjustment material more weather-resistant and adaptable.

In one example, the expandable polyolefin filler 14 includes an expandable polyolefin material and a blowing agent mixed together, wherein the blowing agent includes a low boiling alkane. For example, low boiling alkanes have a boiling point of 30°C to 40°C. During preparation, in an autoclave, the expandable polymer material containing the olefin chain segment and the blowing agent are mixed together. In the autoclave, the expandable polymer materials containing the olefin segments are polymerized together and mixed with the blowing agent. The process of this method is simple, and the expandable polyolefin filler 14 can be formed in one reaction.

It is also possible to first polymerize the expandable polymer material containing olefin links into an expandable polyolefin material, and then add a foaming agent to the expandable polyolefin material, so that the foaming agent penetrates into the expandable polyolefin material. in olefin materials.

The low-boiling alkane includes at least one of petroleum ether, butane, pentane, and the like. All of these materials can volatilize under set trigger conditions, thereby forming cells inside the expandable polyolefin material. A plurality of cells form a foam.

Of course, the types of foaming agents are not limited to the above embodiments, and those skilled in the art can select them according to actual needs.

In one example, the expandable polyolefin filler 14 is at least one of expandable ethylene, propylene and other high molecular polymers. All of the above-mentioned expandable polyolefin fillers 14 can foam in volume under a set trigger condition, thereby buffering the movement of the acoustically improved filler 15 .

For example, expandable polyethylene includes polyethylene and a blowing agent mixed together.

Among them, the expandable polyethylene filler has the characteristics of light weight, no water absorption, anti-aging, strong corrosion performance, strong toughness, non-toxic and non-polluting.

Those skilled in the art can select the type, dosage, etc. of the foaming agent according to actual needs.

In one example, the expandable polyolefin filler 14 is granular or lamellar. The flow of these materials is good and filling in the cavity is easy.

It may be that the expandable polyolefin filler 14 in granular or lamellar form is directly filled into the filling area of the rear acoustic cavity 16 of the sound generating device.

Alternatively, the expandable polyolefin filler 14 in granular or lamellar form is prepared into a predetermined shape and then filled into the filling area of the rear acoustic cavity 16 of the sound generating device.

It is also possible that one of the expandable polyolefin filler 14 and the acoustic improving filler 15 is prepared into a set three-dimensional structure, and the other is filled into the gaps of the three-dimensional structure in the form of particles or sheets.

In one example, the expandable polyolefin filler 14 is in the form of particles. After foaming, the physical size of the expandable polyolefin filler 14 is 0.1 mm-25 mm.

Within this size range, the expandable polyolefin filler 14 has a good cushioning effect on the acoustic improving filler 15, and the foam cell has a good cushioning effect.

In addition, the size of the particles is moderate and will not block the airflow channel of the acoustic improving filler 15, and the acoustic adjusting material has good adsorption and desorption effects on the vibrating airflow.

Further, the expandable polyolefin filler is granular, and after foaming, the physical size of the expandable polyolefin filler 14 is 0.5 mm-2 mm. Within this range, the foaming effect of the foamable polyolefin filler 14 is better for the cushioning effect of the acoustic-improving filler.

In one example, when the acoustic improving filler is not foamed, the density of the expandable polyolefin filler 14 is 0.2 g/mL-1.8 g/mL. Within this density range, the overall density of the acoustic adjustment material is small, which makes the overall weight of the sound emitting device light.

Preferably, before foaming, the density of the expandable polyolefin filler 14 is 0.5g/mL-1.2g/mL, and within this range, the acoustic adjustment material has little effect on the overall weight of the sound-generating device.

In one example, after foaming, the expandable polyolefin filler has a density of 0.005 g/mL to 0.7 g/mL. Within this range, the foam cushioning filler has good cushioning effect on the acoustic improvement filler, high structural strength and good durability.

Preferably, the density of the expandable polyolefin filler is 0.01 g/mL-0.08 g/mL. Within this range, the foam cushioning filler has a better cushioning effect on the acoustic-improving filler.

In one example, the expandable polyolefin filler 14 is triggered by at least one of thermal radiation, optical radiation, and electromagnetic radiation. Under the above irradiation conditions, the blowing agent in the expandable polyolefin filler 14 is volatilized and the volume becomes larger, and cells are formed in the expandable polyolefin material, thereby enabling the foaming of the expandable polyolefin material.

Under the same temperature conditions, under a certain trigger time, the volume of the expandable polyolefin filler 14 can be increased to an appropriate value. If the trigger time is too short, the foaming multiple of the expandable polyolefin filler 14 is small, and The effect of the cushioning acoustic-improving filler 15 is not achieved.

Under the same triggering time and a certain triggering temperature, the volume of the expandable polyolefin filler 14 can be increased to an appropriate value. The smaller the foamed volume of the polyolefin filler 14 is, the less the effect of buffering the acoustically improving filler 15 is achieved.

In addition, the cells in the expandable polyolefin filler 14 are not ruptured.

During the light irradiation, the foaming agent in the expandable polyolefin filler 14 is triggered by means of ultraviolet irradiation. When heated, the blowing agent increases in volume, thereby forming cells within the expandable polyolefin filler.

During electromagnetic radiation, the acoustic modulation material is heated under the action of an alternating magnetic field. The blowing agent volatilizes, thereby forming cells within the expandable polyolefin filler 14 .

The above triggering method is easy to operate and has strong controllability of the size of the cells.

Of course, the triggering method of the expandable polyolefin filler 14 is not limited to the above-mentioned embodiment, and those skilled in the art can select according to actual needs.

In one example, before foaming, the expandable polyolefin filler accounts for 0.01%-35% of the total volume of the acoustic adjustment material; after foaming, the expandable polyolefin filler 14 accounts for the acoustic adjustment material The volume ratio is 0.05%-65%.

Before foaming, within the above ratio range, the proportion of the acoustic improvement filler is large, which can ensure that the acoustic improvement filler is uniformly dispersed in the cavity.

The larger the proportion of the expandable polyolefin filler 14 in the acoustic adjustment material, the smaller the filling amount of the acoustic improvement filler 15, and the lower the effect of the acoustic adjustment material on adsorption and desorption of the vibrating gas; conversely, the expandable The smaller the proportion of the polyolefin filler 14 in the acoustic adjustment material, the less the cushioning effect can be achieved.

Within the above volume ratio range, although the filling amount of the acoustic improvement filler 15 is relatively reduced, the expandable polyolefin filler 14 can form a channel after foaming, so that the vibrating gas can easily enter and exit the acoustic adjustment material, so the acoustic The sound-absorbing effect of the conditioning material is significantly improved.

Due to the buffering effect of the expandable polyolefin filler 14, the acoustic improvement filler 15 has a good shape-retaining effect and good durability.

Further, before foaming, the expandable polyolefin filler accounts for 0.1%-15% of the total volume of the acoustic adjustment material; after foaming, the volume of the foam buffer filler accounts for 5%- 55%. Within this range, the sound absorption effect of the acoustic adjustment material is better and the durability is better.

In one example, the mass of the expandable polyolefin filler 14 accounts for 0.1%-25% of the total mass of the acoustic adjustment material. Within this range, less expandable polyolefin filler 14 is required to achieve a higher filling rate in the cavity.

In addition, since the mass ratio of the expandable polyolefin filler 14 is relatively low, the effect of adsorbing and desorbing the vibrating gas by the acoustic adjustment material will not be affected.

Further, the mass of the expandable polyolefin filler 14 accounts for 1%-5% of the total mass of the acoustic adjustment material. Within this range, the durability of the acoustic adjustment material is good, and the effect of adsorbing and desorbing the vibrating gas is good.

In a specific example, the foaming process of the expandable polyolefin filler 14 includes a first foaming stage and a second foaming stage, the first foaming stage obtains a first foam buffer filler, and the The second foaming stage results in a second foam cushioning filler. The cushioning effect of the expandable polyolefin filler 14 can be flexibly controlled through the staged foaming of the expandable polyolefin filler 14 .

Under the trigger condition, the expandable polyolefin filler 14 has different foamed volumes with different temperatures and/or foaming times. In application after foaming, the first foam buffer filler will undergo a second-stage foaming process with the change of use temperature. During the second-stage foaming process, with different temperatures and/or foaming time, foaming Volume is different. After foaming, because the first foam buffer filler occupies the volume of the back cavity, it has a certain inhibitory effect on the acoustic improvement effect.

Therefore, in the initial stage of filling, the expandable polyolefin filler 14 is foamed in the first stage, and the first foam cushioning filler provides a certain cushioning effect. In the actual application process, if the sound-generating device runs at high power in a high-temperature environment, when the sound-generating device is in high-power operation, the adhesive of the acoustic improvement filler will age, the strength will deteriorate, and the acoustic improvement filler will be easily broken. Under this condition, the expandable polyolefin filler 14 is also more likely to continue foaming, further improving the damping characteristics of the surface of the first foam cushioning filler, providing a buffer for the collision of the acoustic improvement filler, thereby reducing the breakage of the acoustic improvement filler .

Even under normal conditions, the acoustic-improving filler adhesive will slowly age over time, resulting in a loss of strength. During this process, the volume of the first foam buffer filler is also slowly changing, the surface damping properties are increased, and the buffer capacity is enhanced. Under this condition, the expandable polyolefin filler 14 can undergo the second-stage foaming change, The damping is enhanced and the cushioning effect is improved, which effectively avoids the fragile phenomenon caused by the weakening of the acoustic improvement filler.

Specifically, referring to Table 1, the volume of the expandable polyolefin filler 14 after foaming varies with the foaming temperature and/or foaming time. Within a certain temperature range, when the temperature increases, the expandable polyolefin filler 14 changes The damping of the expandable polyolefin filler increases, and the buffer capacity of the expandable polyolefin filler increases; within a certain temperature range, when the time increases, the damping of the expandable polyolefin filler increases, and the expandable polyolefin filler increases. The buffering capacity of olefin fillers is enhanced. Therefore, the degree of foaming of the expandable polyolefin filler 14 can be controlled by the foaming temperature and/or the foaming time.

Table 1-Volume vs. temperature data for the first foaming stage of expandable materials

When the expandable polyolefin filler 14 is used in the sound-generating device, if the expandable polyolefin filler 14 has been foamed to the maximum foaming volume, the strength of the acoustic improvement filler 15 will be weakened during long-term high-temperature use, and there is still fragmentation risks of. If the first foam buffer filler is obtained by passing the expandable polyolefin filler 14 through the first foaming stage, and the first foam buffer filler is not foamed to the maximum foaming volume, then the expandable polyolefin filler 14 is applied to In the sound-generating device, during the long-term high-temperature use of the sound-generating device, the expandable polyolefin filler 14 will undergo a second foaming stage at a high temperature. At this time, the expandable polyolefin filler 14 can continue to foam, and the expandable polyolefin filler After the volume of the olefin filler 14 is increased, it can further buffer the acoustic improvement filler 15 , thereby ensuring the service life of the acoustic improvement filler 15 .

During the long-term high-frequency use of the sound-emitting device, the expandable polyolefin filler 14 may frequently undergo multiple high-temperature foaming processes. Therefore, the second foaming stage here not only refers to a foaming stage, but can also include multiple foaming stages. a foaming stage. For example, when the sound-generating device is operated for a long time and with high power, a higher temperature will be generated inside the sound-generating device. At this time, the expandable polyolefin filler 14 can proceed to the foaming stage. At this time, the expandable polyolefin filler 14 will undergo multiple foaming processes.

Optionally, the volume of the second foam buffer filler is 1-25 times the volume of the first foam buffer filler.

Specifically, after the expandable polyolefin filler 14 is foamed in the first stage, if the maximum foaming volume is not reached, the volume of the expandable polyolefin filler 14 can be further increased after the foaming in the second stage.

In a specific embodiment, referring to Table 2, when the expandable polyolefin filler 14 is in the range of 80-100° C., the foamed volume increases with the increase of temperature.

Table 2 - Data of volume change with temperature in the second foaming stage of expandable materials

Optionally, the physical size of the expandable polyolefin filler 14 before foaming is 20% to 400% of the physical size of the acoustic improvement filler 15, and the density of the expandable polyolefin filler 14 before foaming is The acoustic improvement filler 15 is 30% to 500% of the density.

Specifically, before foaming, the physical size of the expandable polyolefin filler 14 can be comparable to the physical size of the acoustic improvement filler 15, so that the expandable polyolefin filler 14 and the acoustic improvement filler 15 can be mixed uniformly; The physical size of the polyolefin filler 14 is larger or smaller than the physical size of the acoustic improvement filler 15, so that the filling amount of the acoustic adjustment material can be improved. After foaming, the volume of the expandable polyolefin filler 14 is significantly increased, and the density is significantly reduced, which can provide a significant buffering effect on the acoustic-improving filler 15 when it moves and collides.

According to another embodiment of the present disclosure, a sound producing device is provided. The sound-generating device includes a housing 11 , a sound-generating unit 12 and the acoustic adjustment material of the sound-generating device provided by the present disclosure. The interior of the housing 11 forms a cavity. The cavity includes a rear acoustic cavity 16 . The rear acoustic cavity 16 includes the filling area. The filling area may be the entire rear acoustic cavity 16 , or may be a part of the space of the rear acoustic cavity 16 . The sound generating unit 12 is arranged in the cavity. The sound generating unit 12 communicates with the rear sound cavity 16 . The acoustic adjustment material is disposed within the filling zone.

The sounding device has the characteristics of good sounding effect, good low frequency effect and good durability.

In one example, the fill rate of the acoustic modulating material in the filling zone is 45%-95% in an untriggered condition. Within this ratio range, the foaming of the expandable polyolefin filler 14 can provide a buffering effect on the flow and collision of the acoustically improved filler.

Preferably, the filling rate of the acoustic adjustment material in the filling zone is 55%-85% under the condition of not being triggered. Within this range, after being triggered, the acoustic adjustment material can better play a buffering role, and can provide buffers for the flow and collision of the acoustic improvement filler, and prevent the acoustic improvement filler from breaking.

In one example, as shown in FIGS. 3-4 , the expandable polyolefin filler 14 and the acoustic improving filler 15 are both bulk materials. The expandable polyolefin fillers 14 and the acoustic improvement fillers 15 are alternately arranged. In this example, the expandable polyolefin filler 14 can effectively squeeze the acoustic improvement filler 15 in the arrangement direction of the two fillers, so that the acoustic improvement filler 15 can effectively buffer.

In one example, as shown in FIG. 5 , the bulk expandable polyolefin filler 14 and the bulk acoustic improving filler 15 are distributed in an array in the same layer, and the expandable polyolefin filler 14 and the acoustic improving filler 15 are distributed in an array. Staggered settings.

In this example, in the foamed state, the expandable polyolefin filler 14 can effectively squeeze the acoustic improvement filler 15 in all directions in the same layer, thereby effectively buffering the movement of the acoustic improvement filler 15 .

In one example, as shown in FIG. 6 , the expandable polyolefin filler 14 forms a lattice structure. The acoustic improvement filler 15 is filled in the gap 13 formed by the expandable polyolefin filler 14 .

Alternatively, the acoustic improving filler 15 forms a grid structure. The expandable polyolefin filler 14 is filled in the gap 13 formed by the acoustic improving filler 15 .

For example, the grid cells of the grid structure are rectangular, circular, elliptical, triangular, or rhombus-shaped. The grid structure makes the structure of the acoustic adjustment material regular, and the stability and consistency of the adsorption and desorption of the vibrating gas are good.

When filling, the shell 11 is opened, and the grid structure is first placed in the filling area; then, the acoustic improvement filler 15 or the expandable polyolefin filler 14 is filled in the gap 13 formed by the grid structure; next , the casing 11 is closed; finally, the expandable polyolefin filler 14 is foamed by means of heat radiation or the like.

All of the above filling methods can realize the foaming of the expandable polyolefin filler 14 after triggering, thereby squeezing the acoustic improving filler 15 and forming a buffering effect.

In one example, the volume of the expandable polyolefin filler increases by a factor of 2-160 after foaming. In this way, the foam cushioning filler has a good cushioning effect on the acoustic-improving filler 15 .

Preferably, after foaming, the volume of the expandable polyolefin filler increases by 3-110 times. Within this range, the cushioning force of the foam cushioning filler is moderate, and the cushioning effect is better.

According to another embodiment of the present disclosure, a filling method of an acoustic adjustment material is provided.

In one example, the acoustic modulating material is disposed within the filling zone in any of the following ways:

For example, as shown in FIGS. 1-2 , the acoustic adjustment material is in the form of particles. The expandable polyolefin filler 14 is first filled into the filling area, and then the acoustic improving filler 15 is filled into the filling area. In this example, the housing 11 is provided with a filling hole. During filling, the granules are filled from the filling hole into the filling zone. It is possible that the acoustic improving filler 15 employs particles of different physical sizes. The expandable polyolefin filler 14 also uses particles of different physical sizes, so that the filling rate of the acoustic modulation material in the filling area is high.

Alternatively, the particles of the same physical size are used for the acoustic improving filler 15 and the expandable polyolefin filler 14 to ensure the consistency of the acoustic adjustment material.

For example, the acoustic modulation material is in granular form. The acoustic improvement filler 15 is first filled into the filling area, and then the expandable polyolefin filler 14 is filled into the filling area. Likewise, during filling, the granules are filled from the filling hole into the filling zone. It is possible that the acoustic improving filler 15 employs particles of different physical sizes. The expandable polyolefin filler 14 also uses particles of different physical sizes, so that the filling rate of the acoustic modulation material in the filling area is high.

For example, the acoustic modulation material is in granular form. The expandable polyolefin filler 14 and the acoustic improvement filler 15 are mixed first, and then the mixed expandable polyolefin filler 14 and the acoustic improvement filler 15 are filled into the filling area .

Likewise, during filling, the granules are filled from the filling hole into the filling zone. It is possible that the acoustic improving filler 15 employs particles of different physical sizes. The expandable polyolefin filler 14 also uses particles of different physical sizes, so that the filling rate of the acoustic modulation material in the filling area is high.

For example, as shown in FIGS. 3-4 , the expandable polyolefin filler 14 is firstly arranged on at least one wall of the filling area to form an expandable polyolefin filler layer; then, the acoustic improvement filler 15 is into the filling zone.

In this example, the acoustic modulation material may be in granular or lamellar form. The expandable polyolefin filler 14 is bonded to at least one wall of the filling zone using an adhesive. The acoustic improving filler 15 is then filled into the filling zone. Under the triggering condition, the expandable polyolefin filler 14 in the wall is foamed, so as to squeeze the acoustic improvement filler 15 to buffer the movement of the acoustic improvement filler 15 . The foamed expandable polyolefin filler 14 has a buffering effect on the acoustic improvement filler 15 .

Optionally, an expandable polyolefin filler layer is formed on two opposite wall portions of the cavity. Under the condition of being triggered, the expandable polyolefin fillers 14 on the two walls are foamed, so that the acoustic improvement filler 15 is squeezed in two opposite directions, which makes the foam cushioning filler cushion the acoustic improvement filler 15 The effect is better.

In addition, the foamed expandable polyolefin filler layer forms a cushioning effect on the opposite sides of the acoustic improvement filler 15, which makes the acoustic adjustment material more durable.

Further, an expandable polyolefin filler layer is formed on all walls of the cavity. In this way, the expandable polyolefin filler layer forms a buffering effect in any direction of the acoustic improvement filler 15, which makes the acoustic adjustment material more durable.

According to yet another embodiment of the present disclosure, an electronic device is provided. Electronic devices can be, but are not limited to, mobile phones, tablet computers, smart watches, game consoles, learning machines, and the like.

The electronic device includes the sound generating device of the embodiment of the present disclosure. The electronic device is characterized by good acoustics.

<Example 1>

The acoustic adjustment material includes acoustic improving filler 15 and expandable polyethylene filler. Among them, the material of the acoustic-improving filler 15 is zeolite. The zeolite is granular with a physical size of 0.3mm-0.5mm and a density of 0.5g/mL. The mass fraction of expandable polyethylene filler is 2%.

The sound generating device is a miniature speaker module. The volume of the rear acoustic cavity 16 of the micro speaker module is 0.4cc. The acoustic adjustment material is mixed and filled into the rear acoustic cavity 16 .

After the filling is completed, the micro speaker module is placed in an oven and heated at a temperature of 100° C. for 20 minutes to foam the expandable polyethylene filler.

The foamed foam buffer filler has a physical size of 0.5mm-1.3mm, a density of 0.03g/mL, and the volume of the foam buffer filler accounts for 24% of the volume of the acoustic adjustment material.

<Comparative Example 1>

In this example, the acoustic tuning material and speaker module are consistent with the embodiment. Among them, the expandable polyethylene filler is not triggered.

<Comparative Example 2>

The material of the acoustic adjustment material is zeolite. The zeolite is granular with a physical size of 0.3mm-0.5mm and a density of 0.5g/mL.

The sound generating device is a miniature speaker module. This module is the same model as the module used in the embodiment. The acoustic adjustment material is filled into the rear acoustic cavity 16 .

<test item>

1. F0 test: Test the frequency response curves of the three micro-speaker modules respectively, and obtain the F0 of the three micro-speaker modules.

2. Reliability test: Under the same power, the three miniature speaker modules work for 100 hours. Then, test the F0 of the three micro-speaker modules again.

After the test is completed, the acoustic adjustment materials of the three miniature speaker modules are taken out, and the particle integrity of the acoustic improvement filler 15 is observed.

<Test result>

Table 1 - F0 comparison table of three miniature speaker modules

  Comparative Example 2 Comparative Example 1 Example 1 Micro speaker module F0 783Hz 786Hz 788Hz

It can be seen from Table 1 that the F0 difference of the three micro-speakers is very small. This shows that in Example 1, although the expandable polyethylene occupies part of the space in the back cavity after foaming, it does not affect the adsorption and desorption effects of the acoustic adjustment material on the vibrating gas.

Table 2 - Reliability comparison table of two miniature speaker modules

It can be seen from Table 2 that after the reliability test, the F0 of the micro-speaker module of Example 1 changes very little, and the particle state does not change. On the other hand, the F0 of the micro-speaker module of Comparative Example 2 increased significantly, and the particles were severely broken.

This shows that since the particles of the acoustic adjustment material do not change, the reliability of the acoustic adjustment material used in this embodiment is significantly better than that of the acoustic adjustment material used in Comparative Example 2.

<Example 2>

The acoustic adjustment material includes acoustic improving filler 15 and expandable polyethylene filler. The material of the acoustic-improving filler 15 is zeolite. The zeolite is granular with a physical size of 0.3mm-0.5mm and a density of 0.5g/mL. The mass fraction of expandable polyethylene filler is 1.5%.

The sound generating device is a miniature speaker module. The volume of the rear acoustic cavity 16 of the micro speaker module is 0.4cc. The acoustic adjustment material is mixed and filled into the rear acoustic cavity 16 .

After the filling is completed, the micro speaker module is placed in an oven and heated at a temperature of 100° C. for 20 minutes to foam the expandable polyethylene filler.

The foamed foam buffer filler has a physical size of 0.4mm-0.8mm, a density of 0.08g/mL, and the volume of the foam buffer filler accounts for 9% of the volume of the acoustic adjustment material.

<Comparative Example 3>

In this example, the acoustic tuning material and speaker module are consistent with the embodiment. Among them, the expandable polyethylene filler was not triggered.

<Comparative Example 4>

The material of the acoustic adjustment material is zeolite. The zeolite is granular with a physical size of 0.3mm-0.5mm and a density of 0.5g/mL.

The sound generating device is a miniature speaker module. This module is the same model as the module used in the embodiment. The acoustic adjustment material is filled into the rear acoustic cavity 16 .

<test item>

1. F0 test: Test the frequency response curves of the three micro-speaker modules respectively, and obtain the F0 of the three micro-speaker modules.

2. Reliability test: Under the same power, the three miniature speaker modules work for 100 hours. Then, test the F0 of the three micro-speaker modules again.

After the test is completed, the acoustic adjustment materials of the three miniature speaker modules are taken out, and the particle integrity of the acoustic improvement filler 15 is observed.

<Test result>

Table 3 - F0 comparison table of three miniature speaker modules

Acoustic conditioning material Comparative Example 4 Comparative Example 3 Example 2 Micro speaker module F0 783Hz 786Hz 785Hz

It can be seen from Table 3 that the F0 difference of the three micro-speakers is very small. This shows that in Example 2, although the foam occupies part of the volume of the cavity, it does not affect the adsorption and desorption effects of the acoustic adjustment material on the vibrating gas.

Table 4 - Reliability comparison table of two miniature speaker modules

It can be seen from Table 4 that after the reliability test, the F0 of the micro-speaker module of Example 2 changes by 36 Hz, the sound-absorbing particles are partially broken, and the buffering effect is reduced, but the change of F0 is still much smaller than that of Example 4. .

This shows that, since there are less foam fillers in the particles of the acoustic adjustment material, its buffering effect is reduced, but compared with Example 4, the particle integrity of the acoustic adjustment material of this example is still higher, and the effect of adjusting the low frequency is still high. better.

<Example 3>

The acoustic adjustment material includes acoustic improving filler 15 and expandable polypropylene filler. The acoustic improving filler is silica. Silica is granular with a physical size of 0.2mm-0.8mm and a density of 0.6g/mL. . The mass fraction of expandable polypropylene filler is 25%.

The sound generating device is a miniature speaker module. The volume of the rear acoustic cavity 16 of the micro speaker module is 0.4cc. The acoustic adjustment material is mixed and filled into the rear acoustic cavity 16 .

After the filling is completed, the micro speaker module is placed in an oven and heated at a temperature of 100° C. for 30 minutes to foam the expandable polyethylene filler.

After foaming, the physical size of the foamed cushioning filler becomes 20 mm, the density is 0.07 g/mL, and the volume of the foamed cushioning filler accounts for 55% of the volume of the acoustic material filling mixture.

<Comparative Example 5>

In this example, the acoustic tuning material and speaker module are consistent with the embodiment. Among them, the expandable polypropylene filler is not triggered.

<Comparative Example 6>

The material of the acoustic adjustment material is silicon dioxide. Silica is granular with a physical size of 0.2mm-0.8mm and a density of 0.6g/mL.

The sound generating device is a miniature speaker module. This module is the same model as the module used in the embodiment. The acoustic adjustment material is filled into the rear acoustic cavity 16 .

<test item>

1. F0 test: Test the frequency response curves of the three micro-speaker modules respectively, and obtain the F0 of the three micro-speaker modules.

2. Reliability test: Under the same power, the three miniature speaker modules work for 100 hours. Then, test the F0 of the three micro-speaker modules again.

After the test is completed, the acoustic adjustment materials of the three miniature speaker modules are taken out, and the particle integrity of the acoustic improvement filler 15 is observed.

<Test result>

Table 5 - F0 comparison table of three miniature speaker modules

Acoustic conditioning material Comparative Example 6 Comparative Example 5 Example 3 Micro speaker module F0 783Hz 789Hz 782Hz

It can be seen from Table 5 that the F0 of the speaker of Example 3 differs very little from that of Comparative Examples 5 and 6. This shows that, in this Example 3, although the proportion of the acoustic improving filler is small, the performance of adjusting the low frequency of the acoustic adjusting material can be basically unaffected.

Table 6 - Reliability comparison table of two miniature speaker modules

As can be seen from Table 6, after the reliability test, the F0 of the micro-speaker module of Example 3 changed by 4 Hz, and the particles did not change; the F0 of the micro-speaker module of Comparative Example 6 changed by 147 Hz, and the particles were severely broken.

This shows that the reliability of the acoustic adjustment material of this example is significantly due to the acoustic adjustment material of Comparative Example 6.

The above embodiments focus on the differences between the various embodiments. As long as the different optimization features between the various embodiments are not contradictory, they can be combined to form a better embodiment. Repeat.

Although some specific embodiments of the present invention have been described in detail by way of examples, those skilled in the art should understand that the above examples are provided for illustration only and not for the purpose of limiting the scope of the invention. Those skilled in the art will appreciate that modifications may be made to the above embodiments without departing from the scope and spirit of the present invention. The scope of the invention is defined by the appended claims.

Claims (21)

An acoustic adjustment material, which is characterized in that it comprises: an expandable polyolefin filler and an acoustic improvement filler, the expandable polyolefin filler is foamed under the condition of being triggered to become a foam buffer filler, so as to adjust all The acoustically improved filler provides a buffering effect when moving and collided, the volume of the expandable polyolefin filler after foaming changes with the change of temperature and/or foaming time, and the expandable polyolefin filler when the temperature increases The damping is increased, and the cushioning capacity of the expandable polyolefin filler is enhanced. The acoustic adjustment material according to claim 1, wherein the molecular chain of the expandable polyolefin filler contains olefin links, and the molecular structure of the olefin links comprises -CH2-CH2-, -CH( At least one of R)-CH2- and -CH(R)-CH(R)-, wherein R is an alkyl group. The acoustic adjustment material according to claim 2, wherein the expandable polyolefin filler is polymerized from one or more of ethylene, propylene, butene, pentene, and hexene. The acoustic adjustment material according to claim 1, wherein the acoustic improvement filler is made of one or more of activated carbon, zeolite powder, silica, porous alumina, molecular sieve, and metal-organic framework material materials with acoustic properties. The acoustic adjustment material according to claim 1, wherein the expandable polyolefin filler is spherical, quasi-spherical, rod-like, cylindrical, square or radial. The acoustic adjustment material according to claim 1, wherein after foaming, the density of the expandable polyolefin filler is 0.005g/mL-0.7g/mL. The acoustic adjustment material according to claim 1, wherein the expandable polyolefin filler is granular, and after foaming, the physical size of the expandable polyolefin filler is 0.1mm-25mm. The acoustic adjustment material according to claim 1, wherein the expandable polyolefin filler comprises a high molecular polyolefin material and a blowing agent mixed together, wherein the blowing agent comprises a low-boiling alkane . The acoustic adjustment material of claim 1, wherein the expandable polyolefin filler is triggered by at least one of thermal radiation, optical radiation, and electromagnetic radiation. The acoustic adjustment material according to claim 1, wherein, before foaming, the expandable polyolefin filler accounts for 0.01%-35% of the total volume of the acoustic adjustment material; The volume accounts for 0.05%-65% of the total volume of the acoustic modulation material. The acoustic adjustment material according to claim 1, wherein, before foaming, the expandable polyolefin filler accounts for 0.1%-15% of the total volume of the acoustic adjustment material; The volume accounts for 5%-55% of the total volume of the acoustic modulation material. The acoustic adjustment material according to any one of claims 1 to 11, characterized in that, after foaming, the foam cushioning filler formed by the expandable polyolefin filler has an impact on the acoustic improvement filler when it moves and collides. Provides a buffering effect. The acoustic adjustment material according to claim 1, wherein the foaming process of the expandable polyolefin filler comprises a first foaming stage and a second foaming stage, and the first foaming stage obtains the first Foam cushioning filler, the second foaming stage obtains the second foam cushioning filler. The acoustic adjustment material according to claim 13, wherein the volume of the second foam buffer filler is 1-25 times the volume of the first foam buffer filler. A sound-generating device, characterized in that it comprises a housing, a sound-generating unit and the acoustic adjustment material according to any one of claims 1-14, the interior of the housing forms a cavity, and the cavity comprises A rear acoustic cavity, the sound generating unit is arranged in the cavity, the sound generating unit is communicated with the rear acoustic cavity, the rear acoustic cavity includes a filling area, and the acoustic adjustment material is arranged in the filling area. The sound-generating device according to claim 15, wherein, before foaming, the filling rate of the acoustic adjustment material in the filling area is 45%-95%. The sound-generating device according to claim 15, wherein the expandable polyolefin filler and the acoustic-improving filler are both granular materials, The expandable polyolefin filler and the acoustic improving filler are mixed and filled in the filling area. The sound-generating device according to claim 15, wherein the expandable polyolefin filler and the acoustic-improving filler are both bulk materials, The expandable polyolefin filler and the acoustic improvement filler are alternately arranged; or the bulk expandable polyolefin filler and the bulk acoustic improvement filler in the same layer are distributed in an array, and the expandable polyolefin filler and Acoustic-improving filler staggered settings. The sound-generating device according to claim 15, wherein the expandable polyolefin filler forms a lattice structure, and the acoustic improvement filler is filled in the gaps formed by the expandable polyolefin filler; or The acoustic improvement filler forms a lattice structure, and the expandable polyolefin filler is filled in the gaps formed by the acoustic improvement filler. A method for filling an acoustic adjustment material of a sound generating device, characterized in that, the acoustic adjustment material according to any one of claims 1 to 14 is arranged in the filling area of the rear acoustic cavity of the sound generating device in any of the following manners : The acoustic adjustment material is granular, and the expandable polyolefin filler is first filled into the filling area, and then the acoustic improvement filler is filled into the filling area; The acoustic adjustment material is granular, and the acoustic improvement filler is first filled into the filling area, and then the expandable polyolefin filler is filled into the filling area; The acoustic adjustment material is granular, and the expandable polyolefin filler and the acoustic improvement filler are mixed first, and then the mixed expandable polyolefin filler and the acoustic improvement filler are filled into the filling area; First, the expandable polyolefin filler is disposed on at least one wall of the filling area to form an expandable polyolefin filler layer, and then the acoustic improving filler is filled into the filling area. An electronic device, characterized in that it comprises the sound producing device according to any one of claims 15-19.

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