CN111866699B

CN111866699B - Sound generating device's vibrating diaphragm and sound generating device

Info

Publication number: CN111866699B
Application number: CN202011010916.7A
Authority: CN
Inventors: 王翠翠; 惠冰; 凌风光; 李春
Original assignee: Goertek Inc
Current assignee: Goertek Inc
Priority date: 2020-09-23
Filing date: 2020-09-23
Publication date: 2021-01-22
Anticipated expiration: 2040-09-23
Also published as: WO2022062815A1; CN111866699A

Abstract

The invention discloses a vibrating diaphragm of a sound generating device and the sound generating device, wherein the vibrating diaphragm comprises at least one elastic body layer, and the elastic body layer is made of rubber compound; the rubber compound is obtained by mixing raw rubber and filler reinforcing agent, wherein the raw rubber comprises polysulfide rubber, and the particle size of the filler reinforcing agent is 10nm-10 mu m. The obtained diaphragm has good comprehensive performance, can normally work under extreme conditions of high and low temperature, can keep good rigidity, rebound resilience and damping performance, has low distortion and restores the essence of sound.

Description

Sound generating device's vibrating diaphragm and sound generating device

Technical Field

The invention relates to the technical field of acoustic devices, in particular to a vibrating diaphragm of a sound generating device and the sound generating device.

Background

With the rapid development of the 5G era, the electroacoustic device gradually develops towards lightness, thinness, intellectualization, high power and high frequency, consumers demand that the product power is larger and larger, the sound quality is better and better, the performance is more and more stable, and the frequency response is wider and wider, which requires that the electroacoustic device develops towards thinning, miniaturization and high power. The diaphragm is an important component of the speaker, and the quality of the diaphragm directly affects the acoustic performance of the speaker product.

The diaphragm of the existing sound generating device is made of materials mainly including high-modulus plastics (such as PEEK, PAR, PEI, PI, etc.), thermoplastic resin (such as TPU), and silicone rubber.

However, in the process of implementing the embodiments of the present application, the inventors of the present application found that the above-mentioned technology has at least the following technical problems: the plastic with high modulus is light and thin, cannot meet the requirement of high power in the 5G era, and is difficult to bear large mechanical vibration in a high-frequency environment, so that the membrane breaking phenomenon occurs; the thermoplastic resin has poor heat resistance and cold resistance, generates plastic deformation at high temperature and becomes brittle at low temperature; by adopting the silicon rubber, although the thermal stability and the rebound resilience are good, the silicon rubber has symmetrical chemical structure, high stereoregularity, small steric hindrance of the symmetrically substituted methyl group and relatively low modulus or hardness, and under the premise of meeting the same F0 requirement, the damping property of the material is low, so that the product distortion of the silicon rubber diaphragm is large. Therefore, the comprehensive performance of the diaphragm is poor, and the requirement on the comprehensive performance of the sound production device cannot be met.

Therefore, the diaphragm of the sound production device has strong comprehensive performance, can normally work under extreme conditions of high temperature and low temperature, can keep good rigidity, rebound resilience and damping performance, has low distortion and can restore the essence of sound, and the diaphragm becomes a great technical problem in the technical field.

Disclosure of Invention

In order to overcome the defects in the prior art, the invention provides a vibrating diaphragm of a sound generating device and the sound generating device.

The technical problem to be solved by the invention is realized by the following technical scheme:

in a first aspect of the present invention, a diaphragm of a sound generating apparatus is provided, where the diaphragm includes at least one elastomer layer, where the elastomer layer is made of rubber compound; the rubber compound is obtained by mixing raw rubber and filler reinforcing agent, wherein the raw rubber comprises polysulfide rubber, and the particle size of the filler reinforcing agent is 10nm-10 mu m.

Optionally, the raw rubber further comprises at least one of nitrile rubber, hydrogenated nitrile rubber, styrene butadiene rubber and natural rubber.

Optionally, the filler reinforcing agent is at least one of carbon black, calcium carbonate, nano titanium dioxide, barium sulfate, montmorillonite and mica.

Optionally, the content of the filler reinforcing agent is 5% -60% of the total amount of the rubber compound.

Optionally, the raw materials of the rubber compound further comprise a vulcanizing agent and a vulcanization accelerator.

Optionally, the vulcanizing agent is at least one of metal oxide, metal peroxide, organic oxide, organic peroxide and sulfur, and the vulcanization accelerator is thiuram polysulfide.

Optionally, the vulcanizing agent and the vulcanization accelerator are contained in an amount of 0.5 to 5% of the total amount of the rubber compound.

Optionally, the diaphragm further includes at least one thermoplastic elastomer layer and/or at least one engineering plastic layer.

Optionally, the material of the thermoplastic elastomer layer is at least one selected from polyester thermoplastic elastomers, polyurethane thermoplastic elastomers, polyamide thermoplastic elastomers, polystyrene thermoplastic elastomers, polyolefin thermoplastic elastomers, and silicone thermoplastic elastomers.

Optionally, the engineering plastic layer is made of at least one of polyamide, polycarbonate, polyformaldehyde, polyethylene terephthalate, polybutylene terephthalate, polyarylsulfone, polyethersulfone, polyimide, polyphenylene sulfide, polyarylate, polyphenyl ester, polyaryletherketone and polyetheretherketone.

Optionally, the tensile strength of the diaphragm is 4-25MPa, and the tear strength is 15-100N/mm.

According to another aspect of the present invention, a sound generating apparatus is provided, which includes the above-mentioned diaphragm.

The invention has the following beneficial effects:

the vibrating diaphragm comprises at least one elastic body layer, wherein the elastic body layer is made of rubber compound; the rubber compound is obtained by mixing raw rubber and filler reinforcing agent, wherein the raw rubber comprises polysulfide rubber, and the particle size of the filler reinforcing agent is 10nm-10 mu m. The obtained diaphragm has good comprehensive performance, can normally work under extreme conditions of high temperature and low temperature, can keep good rigidity, rebound resilience and damping performance, has low distortion and restores the essence of sound.

The invention has the advantages of low material cost, simple processing technology and good forming consistency, and can also greatly improve the production efficiency.

Drawings

Fig. 1 is a THD test curve of a diaphragm of example 1 of the present invention and a diaphragm of comparative example 4.

Detailed Description

The raw materials and equipment used in the invention are common raw materials and equipment in the field if not specified; the methods used in the present invention are conventional in the art unless otherwise specified.

Unless otherwise defined, terms used in the present specification have the same meaning as those generally understood by those skilled in the art, but in case of conflict, the definitions in the present specification shall control.

The use of "including," "comprising," "containing," "having," or other variations thereof herein, is meant to encompass the non-exclusive inclusion, as such terms are not to be construed. The term "comprising" means that other steps and ingredients can be added that do not affect the end result. The term "comprising" also includes the terms "consisting of …" and "consisting essentially of …". The compositions and methods/processes of the present invention comprise, consist of, and consist essentially of the essential elements and limitations described herein, as well as any of the additional or optional ingredients, components, steps, or limitations described herein.

All numbers or expressions referring to quantities of ingredients, process conditions, etc. used in the specification and claims are to be understood as modified in all instances by the term "about". All ranges directed to the same component or property are inclusive of the endpoints, and independently combinable. Because these ranges are continuous, they include every value between the minimum and maximum values. It should also be understood that any numerical range recited herein is intended to include all sub-ranges within that range.

As described in the background art, the prior art has the technical problems that the diaphragm has poor comprehensive performance, can not simultaneously meet the requirements of normal operation under extreme conditions of high and low temperature, can keep good rigidity, rebound resilience and damping performance, and has low distortion and essential requirement of sound restoration. In order to solve the technical problem, the invention provides a vibrating diaphragm of a sound generating device.

In order to solve the technical problems, the technical scheme in the embodiment of the invention has the following general idea:

a vibrating diaphragm of a sound production device comprises at least one elastic body layer, wherein the elastic body layer is made of rubber compound; the rubber compound is obtained by mixing raw rubber and filler reinforcing agent, wherein the raw rubber comprises polysulfide rubber, and the particle size of the filler reinforcing agent is 10nm-10 mu m. Through the arrangement, the obtained vibrating diaphragm has good comprehensive performance, can normally work under extreme conditions of high temperature and low temperature, can keep good rigidity, rebound resilience and damping performance, has low distortion and restores the essence of sound.

The raw rubber includes polysulfide rubber, and in the examples of the present application, there is no particular limitation on the type of the polysulfide rubber, and the type of the conventional polysulfide rubber known to those skilled in the art may be used, and the polysulfide rubber may be any one of a-type polysulfide rubber, FA-type polysulfide rubber, and ST-type polysulfide rubber, for example.

The diaphragm prepared by adopting polysulfide rubber has good rigidity, rebound resilience and damping performance.

In the embodiment of the invention, the raw rubber can also comprise at least one of nitrile rubber, hydrogenated nitrile rubber, styrene butadiene rubber and natural rubber. By compounding the polysulfide rubber with other rubbers, the rigidity, resilience and damping performance of the vibrating diaphragm can be further improved.

In the embodiment of the present invention, the filler reinforcing agent is at least one of carbon black, calcium carbonate, nano titanium dioxide, barium sulfate, montmorillonite and mica, but is not limited thereto, and may be other filler reinforcing agents not listed in this embodiment but known by those skilled in the art. More preferably, the filler reinforcing agent is carbon black.

The surface of the filler reinforcing agent has a group such as hydrogen, carboxyl group, lactone group, radical, quinone group, or the like, which can undergo substitution, reduction, oxidation, or the like. After the filler reinforcing agent is mixed into the polysulfide rubber, due to the strong interaction between the interfaces of the molecular chain segments of the filler reinforcing agent and the polysulfide rubber, when the material is stressed, the molecular chain is easy to slide on the surfaces of the filler reinforcing agent particles, but is not easy to be separated from the filler reinforcing agent particles, the polysulfide rubber and the filler reinforcing agent particles form a strong slidable bond, and the mechanical strength is increased.

The particle size of the filler reinforcement is 10nm to 10 μm, such as 10nm, 50nm, 100nm, 300nm, 500nm, 800nm, 1 μm, 2 μm, 5 μm, 8 μm, 10 μm and any value in between.

The inventors have repeatedly found that the particle size of the filler reinforcing agent has an important influence on the overall performance of the diaphragm, which is a problem that those skilled in the art never realize.

Taking carbon black as an example, carbon black is an amorphous structure, and particles form aggregates by physicochemical bonding with each other. The specific surface area of carbon black means the sum of the surface areas of carbon black particles per unit mass. The surface area of the carbon black includes an outer surface area (smooth surface area) and an inner surface area (void inner surface area), and the total surface area of the carbon black is the sum of the outer surface area and the inner surface area. The specific surface area of carbon black is inversely proportional to the particle size, i.e., a carbon black having a small particle size has a large specific surface area and a carbon black having a large particle size has a small specific surface area. The carbon black reinforces the rubber by bonding the aggregate surface with the molecular chain of the rubber. The combination of the carbon black surface and the rubber molecular chain has two limits, one is the micropores of the carbon black aggregate, the rubber molecular chain can not enter the micropores, and the other is the rough surface of the carbon black aggregate, and the rubber molecular chain can not contact the concave surface of the rough surface. Carbon black as filler reinforcing agent must be combined with rubber molecular chain to play the reinforcing role, the combination is completed depending on the surface of carbon black, and the reinforcing role depends on the combination degree and the surface size. The smaller the carbon black particles are, the smaller the crystallite size is, the more the crystallite edges, lattice defects and unsaturated charges are, namely the surface activity is higher, the higher the surface energy is, the higher the reinforcing effect on the rubber is, because the surface of the carbon black with the large surface activity is provided with more active points, the number of network structures formed by reaction with rubber molecules in the vulcanization process of the rubber compound is large, and the network structures formed by the carbon black and the rubber endow the vulcanized rubber with strength. However, the too small carbon black particles result in too large surface activity of carbon black, and a large number of bound rubbers are produced during kneading, so that the Mooney viscosity of the rubber material is increased, the die swell ratio and the shrinkage ratio of a semi-finished product are increased during extrusion, the extrusion rate is slowed down, and the too small carbon black particle diameter causes difficulty in dispersion during kneading due to high interparticle cohesion and easy agglomeration, and reduces plasticity, thereby deteriorating the extrusion performance and greatly affecting the processability of unvulcanized rubber.

The inventor unexpectedly finds that the particle size of the filler reinforcing agent is controlled to be 10nm-10 mu m, the processing performance of the unvulcanized rubber is met, the dispersion capacity is good, the roll releasing performance is good, the specific surface area is large, the filler reinforcing agent and the rubber are tightly combined, the reinforcement is enhanced, the film is not easily broken in the high-power vibration process, and the unexpected technical effect is achieved.

In the examples of the present invention, the content of the filler reinforcing agent is 5% to 60% of the total amount of the rubber compound, for example, 5%, 10%, 20%, 30%, 40%, 50%, 60% and any value therebetween. More preferably, the content of the filler reinforcing agent is 40-50% of the total amount of the rubber compound. If the content of the filler reinforcing agent is less than 5%, the mechanical strength and the elongation at break of the rubber compound are small, because the amount of the carbon black is small, the carbon black is unevenly dispersed in a matrix and is difficult to achieve a reinforcing effect; if the content of the filler reinforcing agent is higher than 60%, the elongation at break of the rubber compound is sharply reduced, and after the vibrating diaphragm is manufactured, the risk of breaking the diaphragm exists in long-term use. In the invention, the content of the filler reinforcing agent is controlled to be 5-60% of the total amount of the rubber compound, after the rubber compound is vulcanized, the damping is proper, the polarization of the vibrating diaphragm is inhibited, the tone quality is good, the distortion is low, the mechanical property is excellent, the acoustic property and the reliability condition are met, and the unexpected technical effect is obtained.

In the embodiment of the invention, the raw materials of the rubber compound also comprise a vulcanizing agent and a vulcanization accelerator.

In the examples of the present invention, the kind of the vulcanizing agent is not particularly limited, and may be any of general vulcanizing agents known to those skilled in the art, and preferably, at least one of a metal oxide, a metal peroxide, an organic oxide, an organic peroxide, and sulfur is used as the vulcanizing agent. Among them, as the metal oxide, manganese dioxide, zinc oxide, lead dioxide; as the metal peroxide, lead peroxide; as the organic peroxide, there may be exemplified one or more of dicumyl peroxide (DCP), 1, 3-bis (t-butylperoxyisopropyl) benzene, 1, 4-bis (t-butylperoxyisopropyl) 3, 3, 5-trimethylcyclohexane, 2, 5-dimethyl-2, 5-di-t-butylperoxy) hexane, n-butyl-4, 5-bis (t-butylperoxy) valerate.

In the examples of the present invention, the kind of the vulcanization accelerator is not particularly limited, and may be any of the usual vulcanization accelerators known to those skilled in the art, and it is preferable to use thiuram polysulfide as the vulcanization accelerator. As the thiuram polysulfide, at least one member selected from the group consisting of tetramethylthiuram monosulfide, tetramethylthiuram disulfide, tetraethylthiuram disulfide, tetrabutylthiuram disulfide, diisobutylfuram disulfide and bis (1, 5-pentamethylene) thiuram tetrasulfide can be used by way of example.

In the examples of the present invention, the vulcanizing agent and the vulcanization accelerator are contained in an amount of 0.5% to 5% by weight, for example, 0.5%, 0.8%, 1%, 2%, 3%, 4%, 5% by weight and any value therebetween, based on the total amount of the rubber compound. If the content of the vulcanizing agent and the vulcanization accelerator is lower than 0.5%, the effective crosslinking density of the rubber compound is low, the mechanical strength of the material is poor, the material is easy to deform in the process of preparing a vibrating diaphragm for a long time, and the vulcanization rate of the material is low, so that the production efficiency is severely limited, and the production cost is increased; if the content of the vulcanizing agent and the vulcanization accelerator is more than 5%, the crosslink density of the rubber compound is too high, which may aggravate the nonuniformity of the crosslink distribution and cause the nonuniformity of the stress distribution. In the invention, the content of the vulcanizing agent and the vulcanization accelerator is controlled to be 0.5-5% of the total amount of the rubber compound, and the rubber compound has better processability, mechanical property, oil resistance and thermal aging resistance.

The diaphragm provided by the invention can be a single-layer structure and can also be a multi-layer composite diaphragm.

The single-layer diaphragm is a diaphragm composed of one layer of the elastic body layer.

The composite diaphragm is formed by sequentially laminating a plurality of elastomer layers. Alternatively, the composite diaphragm may include at least one elastomer layer and at least one film layer made of other materials. The elastomer layer is bonded and compounded with film layers made of other materials to form the composite diaphragm made of various materials. In addition, the multiple film layers can be compounded in a hot pressing mode and the like, and the composite diaphragm is further formed. The composite diaphragm may be a two-layer, three-layer, four-layer or five-layer composite diaphragm, which is not limited in the present invention. At least one film layer in the composite diaphragm is the elastomer layer provided by the invention.

For film layers made of other materials, a thermoplastic elastomer layer and/or an engineering plastic layer may be preferred.

In the embodiment of the present invention, the material of the thermoplastic elastomer layer is not particularly limited, and may be a common thermoplastic elastomer well known to those skilled in the art, and the material of the thermoplastic elastomer layer is at least one selected from polyester-based thermoplastic elastomer, polyurethane-based thermoplastic elastomer, polyamide-based thermoplastic elastomer, polystyrene-based thermoplastic elastomer, polyolefin-based thermoplastic elastomer, and silicone-based thermoplastic elastomer, for example.

In the embodiment of the present invention, the material of the engineering plastic layer is not particularly limited, and a common engineering plastic known to those skilled in the art may be used, and the material of the engineering plastic layer is at least one selected from polyamide, polycarbonate, polyoxymethylene, polyethylene terephthalate, polybutylene terephthalate, polyarylsulfone, polyethersulfone, polyimide, polyphenylene sulfide, polyarylate, polyphenylene ether, polyaryletherketone, and polyetheretherketone, for example.

In the embodiment of the invention, the tensile strength of the diaphragm is 4-25MPa, and the tearing strength is 15-100N/mm. The vibrating diaphragm has proper mechanical property, and the vibrating diaphragm is not easy to have the reliability problems of film breaking and the like when being used in a module.

In the invention, the preparation method of the vibrating diaphragm of the sound production device comprises the following steps: mixing raw rubber and filler reinforcing agent to obtain rubber compound; and (4) taking the rubber compound, and forming to obtain the vibrating diaphragm.

The invention also provides a sound production device which comprises a magnetic circuit system and a vibration system which are matched with each other, wherein the vibration system comprises the vibrating diaphragm.

In order to better understand the technical solutions, the technical solutions will be described in detail with reference to specific examples, which are only preferred embodiments of the present invention and are not intended to limit the present invention.

Example 1

A vibrating diaphragm of a sound production device comprises an elastic body layer, wherein the elastic body layer is made of rubber compound; the rubber compound is obtained by mixing raw rubber, a filler reinforcing agent, a vulcanizing agent and a vulcanization accelerator, wherein the raw rubber comprises polysulfide rubber, and the particle size of the filler reinforcing agent is 10 nm.

The filler reinforcing agent adopts carbon black; the content of the filler reinforcing agent is 5% of the total amount of the rubber compound.

The vulcanizing agent adopts sulfur, and the vulcanization accelerator adopts thiuram polysulfide; the content of the vulcanizing agent and the vulcanization accelerator is 0.5 percent of the total amount of the rubber compound.

Example 2

Based on example 1, the difference is only that: the particle size of the filler reinforcement described in example 2 was 4 μm.

Example 3

Based on example 1, the difference is only that: the particle size of the filler reinforcement described in example 3 was 10 μm.

Example 4

Based on example 1, the difference is only that: the content of the filler reinforcement in example 4 was 10% of the total amount of the rubber compound.

Example 5

Based on example 1, the difference is only that: the content of the filler reinforcement in example 5 was 60% of the total amount of the rubber compound.

Example 6

Based on example 1, the difference is only that: the vulcanizing agent and the vulcanization accelerator were contained in an amount of 1% of the total amount of the rubber compound in example 6.

Example 7

Based on example 1, the difference is only that: the vulcanizing agent and the vulcanization accelerator were contained in an amount of 5% by weight based on the total amount of the rubber compound in example 7.

Example 8

A vibrating diaphragm of a sound production device comprises an elastic body layer, wherein the elastic body layer is made of rubber compound; the rubber compound is obtained by mixing raw rubber, a filler reinforcing agent, a vulcanizing agent and a vulcanization accelerator, wherein the raw rubber comprises polysulfide rubber and nitrile rubber, and the particle size of the filler reinforcing agent is 100 nm.

The filler reinforcing agent is calcium carbonate, and the content of the filler reinforcing agent is 30% of the total amount of the rubber compound.

The vulcanizing agent is zinc oxide, and the vulcanization accelerator is thiuram polysulfide; the content of the vulcanizing agent and the vulcanization accelerator is 2 percent of the total amount of the rubber compound.

Example 9

A vibrating diaphragm of a sound production device comprises an elastomer layer and a thermoplastic elastomer layer, wherein the elastomer layer is made of rubber compound; the rubber compound is obtained by mixing raw rubber, a filler reinforcing agent, a vulcanizing agent and a vulcanization accelerator, wherein the raw rubber comprises polysulfide rubber and styrene butadiene rubber, and the particle size of the filler reinforcing agent is 500 nm.

The filler reinforcing agent adopts nano titanium dioxide; the content of the filler reinforcing agent is 40% of the total amount of the rubber compound.

The vulcanizing agent adopts lead peroxide, and the vulcanization accelerator adopts thiuram polysulfide; the content of the vulcanizing agent and the vulcanization accelerator is 3 percent of the total amount of the rubber compound.

The thermoplastic elastomer layer is made of polyester thermoplastic elastomer.

Example 10

A vibrating diaphragm of a sound production device comprises an elastic body layer and an engineering plastic layer, wherein the elastic body layer is made of rubber compound; the rubber compound is obtained by mixing raw rubber, filler reinforcing agent, vulcanizing agent and vulcanization accelerator, wherein the raw rubber comprises polysulfide rubber and natural rubber, and the particle size of the filler reinforcing agent is 8 mu m.

The filler reinforcing agent adopts montmorillonite and mica; the content of the filler reinforcing agent is 50% of the total amount of the rubber compound.

The vulcanizing agent adopts organic peroxide, and the vulcanization accelerator adopts thiuram polysulfide; the content of the vulcanizing agent and the vulcanization accelerator is 2.5 percent of the total amount of the rubber compound.

The engineering plastic layer is made of polyether-ether-ketone.

Comparative example 1

Based on example 1, the difference is only that: the particle size of the filler reinforcement described in comparative example 1 was 1 nm.

Comparative example 2

Based on example 1, the difference is only that: the particle size of the filler reinforcement described in comparative example 2 was 12 μm.

Comparative example 3

Based on example 1, the difference is only that: the content of the filler reinforcing agent in comparative example 3 was 0.5% of the total amount of the rubber compound.

Comparative example 4

Based on example 1, the difference is only that: the content of the filler reinforcing agent in comparative example 4 was 70% of the total amount of the rubber compound.

Comparative example 5

Based on example 1, the difference is only that: in comparative example 5, the content of the vulcanizing agent and the vulcanization accelerator was 0.1% of the total amount of the rubber compound.

Comparative example 6

Based on example 1, the difference is only that: the vulcanizing agent and the vulcanization accelerator were contained in an amount of 15% of the total amount of the rubber compound in comparative example 6.

Test example

In order to verify the influence of the particle size of the filler reinforcing agent of the invention on the product performance, the vibration films prepared in examples 1-3 and comparative examples 1-2 were respectively subjected to relevant performance tests, and the test results are shown in table 1.

TABLE 1 Effect of particle size of Filler Reinforcement on product Properties

As can be seen from Table 1, the smaller the particle size of the carbon black, the better the reinforcing effect, the higher the tear strength and 100% modulus, the higher the corresponding product F0; the larger the carbon black particle size is, the poorer the reinforcing effect is, the lower the tear strength and 100% definite elongation modulus are, the lower the corresponding product F0 is, although F0 is low, the tear strength is poor, and the membrane is easy to break in the high-power vibration process. Meanwhile, through the test of the processing performance, the comparative example 1 has the defects of difficult dispersion, reduced plasticity, poor roll releasing performance and bad extrusion performance during mixing, and has great influence on the processing performance of the unvulcanized rubber. Tests prove that the particle size of the filler reinforcing agent is controlled to be 10nm-10 mu m, the processing performance of the unvulcanized rubber is met, the dispersion capability is good, the roll-off performance is good, the specific surface area is large, the filler reinforcing agent and the rubber are tightly combined, the reinforcement is enhanced, the film is not easily broken in the high-power vibration process, and the unexpected technical effect is achieved.

In order to verify the influence of the content of the filler reinforcing agent of the invention on the product performance, the diaphragms prepared in example 1, example 4, example 5 and comparative examples 3 to 4 were respectively subjected to relevant performance tests, and the test results are shown in table 2.

TABLE 2 Effect of Filler Reinforcement content on product Properties

As can be seen from table 2, when the carbon black content is 0.5%, both the tensile strength and the elongation at break of the diaphragm are small; with the increase of the content of the carbon black, the reinforcement is enhanced, the tensile strength of the vibrating diaphragm is increased, and the elongation at break is gradually reduced; when the carbon black content is 90%, the elongation at break thereof is drastically reduced, and there is a risk of membrane rupture in long-term use after the diaphragm is manufactured.

Fig. 1 is a THD test curve of the diaphragm of example 1 of the present invention and the diaphragm of comparative example 4, and it can be seen from fig. 1 that the diaphragm of example 1 of the present invention has a lower THD (total harmonic distortion) and no spike or the like, compared to the diaphragm of comparative example 4. This shows that the diaphragm of embodiment 1 of the present invention has appropriate damping, and the vibration uniformity of each portion of the diaphragm is good, so that the presented sound is better and the listening stability is more excellent.

In conclusion, tests prove that the content of the filler reinforcing agent is controlled to be 5% -60% of the total amount of the rubber compound, after the rubber compound is vulcanized, the damping is proper, the polarization of the vibrating diaphragm is inhibited, the sound quality is good, the distortion is low, the mechanical property is excellent, the acoustic performance and the reliability condition are met, and the unexpected technical effect is achieved.

In order to verify the influence of the contents of the vulcanizing agent and the vulcanization accelerator of the present invention on the product performance, the diaphragms prepared in example 1, example 6, example 7 and comparative examples 5 to 6 were subjected to the relevant performance tests, respectively, and the test results are shown in table 3 and the vulcanization data is shown in table 4.

TABLE 3 influence of the vulcanizing agent and vulcanization accelerator contents on the product Properties

TABLE 4 Effect of vulcanizing agent and vulcanization accelerator content on vulcanization data

As can be seen from tables 3 and 4, when the content of the vulcanizing agent and the vulcanization accelerator is 0.1%, the effective crosslinking density of the material is low, and the mechanical strength of the material is poor; with the increase of the contents of the vulcanizing agent and the vulcanization accelerator, the scorching time of the rubber material is shortened, the vulcanization speed is accelerated, the elongation at break is reduced, and the glass transition temperature is increased. However, when the content of the vulcanizing agent and the vulcanization accelerator is 15%, the crosslink density becomes too high, which results in an increase in the nonuniformity of the crosslink distribution and an uneven stress distribution. The content of the vulcanizing agent and the vulcanization accelerator is controlled to be 0.5-5% of the total amount of the rubber compound, and the rubber compound has good processability, mechanical property, oil resistance and thermal aging resistance.

The above-mentioned embodiments only express the embodiments of the present invention, and the description is more specific and detailed, but not understood as the limitation of the patent scope of the present invention, but all the technical solutions obtained by using the equivalent substitution or the equivalent transformation should fall within the protection scope of the present invention.

Claims

1. The vibrating diaphragm of the sound production device is characterized by comprising at least one elastic body layer, wherein the elastic body layer is made of rubber compound; the rubber compound is obtained by mixing raw rubber and filler reinforcing agent, wherein the raw rubber comprises polysulfide rubber, and the particle size of the filler reinforcing agent is 50-100 nm; the content of the filler reinforcing agent is 5-60% of the total amount of the rubber compound.

2. The diaphragm of claim 1, wherein the raw rubber further comprises at least one of nitrile rubber, hydrogenated nitrile rubber, styrene butadiene rubber, and natural rubber.

3. The diaphragm of claim 1, wherein the filler reinforcing agent is at least one of carbon black, calcium carbonate, nano titanium dioxide, barium sulfate, montmorillonite and mica.

4. The diaphragm of claim 1, wherein the raw materials of the rubber compound further comprise a vulcanizing agent and a vulcanization accelerator.

5. The diaphragm of claim 4, wherein the vulcanizing agent is at least one of metal oxide, metal peroxide, organic oxide, organic peroxide and sulfur, and the vulcanization accelerator is thiuram polysulfide.

6. The diaphragm of a sound-generating apparatus as claimed in claim 4, wherein the contents of said vulcanizing agent and said vulcanization accelerator are 0.5% to 5% of the total amount of said rubber compound.

7. The diaphragm of claim 1, wherein the diaphragm further comprises at least one thermoplastic elastomer layer and/or at least one engineering plastic layer.

8. The diaphragm of the sound generating apparatus as claimed in claim 7, wherein the thermoplastic elastomer layer is made of at least one of a polyester-based thermoplastic elastomer, a polyurethane-based thermoplastic elastomer, a polyamide-based thermoplastic elastomer, a polystyrene-based thermoplastic elastomer, a polyolefin-based thermoplastic elastomer, and a silicone-based thermoplastic elastomer; the engineering plastic layer is made of at least one of polyamide, polycarbonate, polyformaldehyde, polyethylene terephthalate, polybutylene terephthalate, polyarylsulfone, polyethersulfone, polyimide, polyphenylene sulfide, polyarylate, polyphenyl ester, polyaryletherketone and polyetheretherketone.

9. The diaphragm of the sound-generating apparatus as claimed in claim 1, wherein the tensile strength of the diaphragm is 4 to 25MPa, and the tear strength is 15 to 100N/mm.

10. A sound-emitting device, comprising the diaphragm according to any one of claims 1 to 9.