CN118283490A

CN118283490A - Vibrating plate, vibrating diaphragm assembly and sound generating device

Info

Publication number: CN118283490A
Application number: CN202410305219.6A
Authority: CN
Inventors: 王述强; 李志�
Original assignee: Weifang Geldanna Electronic Technology Co ltd
Current assignee: Weifang Geldanna Electronic Technology Co ltd
Priority date: 2024-03-15
Filing date: 2024-03-15
Publication date: 2024-07-02

Abstract

The invention provides a vibrating plate, a vibrating diaphragm assembly and a sound generating device, wherein the vibrating plate comprises a hard material layer and an intermediate layer arranged between any two adjacent hard material layers, and at least one intermediate layer is a chopped fiber composite layer; wherein the Young's modulus of the hard material layer is greater than 50GPa. The vibrating plate has the advantages of light weight, high flexural modulus and high rigidity.

Description

Vibrating plate, vibrating diaphragm assembly and sound generating device

Technical Field

The invention belongs to the technical field of transduction, and particularly relates to a vibrating plate, a vibrating diaphragm assembly and a sound generating device.

Background

In a speaker, a diaphragm is one of the most core components, and the mass and rigidity of the diaphragm play a decisive role in the performance of the speaker.

In the current speaker application environments, such as vehicle-mounted application environments, there are many restrictions on the power and the shape of the speaker, and the speaker is required to be light and thin and have high sensitivity. Therefore, a diaphragm of a speaker is required to have an extremely high modulus and an extremely light mass, so that a high frequency response range and an extremely high sensitivity can be combined, and a transient response can be also excellent.

The prior art loudspeaker diaphragm is not capable of satisfying both high modulus and light weight, for example, although aluminum has a low density in metal, aluminum has a density of up to 2.7g/cm ³, which is much higher than paper. The vibration quality of the aluminum material is larger and the sensitivity is lower. For another example, the density of the honeycomb paper material can be reduced to 0.2g/cm ³, the honeycomb paper composite material has obvious weight reduction effect, but the modulus is lower, the honeycomb paper is difficult to thin, and the thickness of the common thin-layer honeycomb paper composite material is as low as 0.5mm at least, and the cost is higher. For another example, the modulus of conventional materials such as paper or PP is lower than 10GPa.

It can be seen that there is a need to develop a material having a low density and a high modulus as a vibration plate.

Disclosure of Invention

An object of the present invention is to provide a diaphragm assembly, which can at least solve the technical problems that the conventional diaphragm is difficult to be lightweight and has high modulus.

The invention further provides a vibrating diaphragm assembly with the vibrating plate.

The invention also provides a sound generating device with the vibrating diaphragm assembly.

According to a first aspect of the present invention, there is provided a vibration plate comprising hard material layers and an intermediate layer provided between any two adjacent hard material layers, at least one of the intermediate layers being a chopped fiber composite layer; wherein the Young's modulus of the hard material layer is greater than 50GPa.

Alternatively, the vibration plate has an overall density of 0.05g/cm ³～2.0g/cm³.

Optionally, the chopped fiber composite layer has a density of 0.1g/cm ³～1.6g/cm³.

Optionally, the total thickness of the chopped fiber composite layer is 20% -96% of the total thickness of the vibration plate.

Optionally, the compression modulus of the chopped fiber composite layer is 50 MPa-2 GPa.

Optionally, the chopped fiber composite layer is composed of inorganic fibers and synthetic fibers; wherein the inorganic fiber comprises at least one of carbon fiber, basalt fiber, glass fiber and silicon carbide fiber; and/or the synthetic fiber comprises at least one of polypropylene fiber, nylon fiber, polyester fiber, aramid fiber, polyimide fiber, polyethylene fiber, polyacrylonitrile fiber, polyvinyl formal fiber, polyvinyl chloride fiber, polyurethane elastic fiber and polyolefin elastic fiber.

Optionally, the length center value of the inorganic fiber is 0.5 mm-60 mm.

Optionally, the inorganic fibers are present in an amount of 10% to 50% of the total volume of the fibers in the chopped fiber composite layer.

Optionally, the hard material layer is a metal layer, an inorganic nonmetallic material layer or a carbon fiber prepreg layer; and/or the hard material layer has a density of 1.2g/cm ³～8.1g/cm³; and/or wherein the Young's modulus of the hard material layer is greater than 50GPa.

Optionally, the metal layer is at least one of an aluminum film layer and a steel film layer.

Optionally, the inorganic nonmetallic material layer is a glass layer, and the mass content of silicon oxide in the glass layer is 50% -95%; or the nonmetallic material layer is a ceramic layer, and the ceramic layer is any one of alumina, zirconia, silicon carbide, aluminum nitride and silicon nitride.

Optionally, the total thickness of the hard material layer is 2% -40% of the total thickness of the vibration plate.

Optionally, the thickness of each hard material layer is the same, and the thickness of each hard material layer is 5 μm to 500 μm.

Optionally, at least one of the hard material layers has a thickness that is different from the thickness of the other hard material layers.

Optionally, the vibration plate comprises three layers, and the materials of the hard material layers on two sides are the same; or the vibration plate comprises three layers, and the materials of the hard material layers at two sides are different.

Optionally, the vibration plate includes the steel film layer, the chopped fiber composite layer, and the steel film layer stacked in this order.

Optionally, the vibration plate comprises five layers, and the chopped fiber composite layer is arranged between any two adjacent hard material layers.

Optionally, the vibration plate further includes: an adhesive layer between the hard material layer and the chopped fiber composite layer to connect the hard material layer and the chopped fiber composite layer; the thickness of the adhesive layer is 1-200 mu m.

According to a second aspect of the present invention, there is provided a diaphragm assembly comprising a diaphragm and any one of the diaphragms described above.

According to a third aspect of the present invention, there is provided a sound generating apparatus comprising a diaphragm assembly as described in any one of the above.

The vibrating plate provided by the embodiment of the invention comprises the hard material layers and the intermediate layers arranged between any two adjacent hard material layers, wherein at least one intermediate layer is a chopped fiber composite layer, so that a three-dimensional net-shaped structure is formed, and the density of the vibrating plate can be reduced; and the Young's modulus of the hard material layer is more than 50GPa, which is beneficial to the maintenance of high rigidity and high specific modulus of the vibration plate while the vibration plate has light weight.

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

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 structural view of a vibration plate according to an embodiment of the present invention;

Fig. 2 is a graph showing the frequency response curves of comparative example 5 and example 1.

Reference numerals

A vibration plate 100;

a hard material layer 10;

An intermediate layer 20.

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 the components and steps, numerical expressions and numerical values set forth in these embodiments do not limit the scope of the present invention unless it is specifically stated otherwise.

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

Techniques, methods, and apparatus known to one of ordinary skill in the relevant art may not be discussed in detail, but are intended to be part of the specification where appropriate.

In all examples shown and discussed herein, any specific values should be construed as merely illustrative, and not a limitation. Thus, other examples of exemplary embodiments may have different values.

It should be noted that: like reference numerals and letters denote like items in the following figures, and thus once an item is defined in one figure, no further discussion thereof is necessary in subsequent figures.

Hereinafter, the vibration plate 100 according to the embodiment of the present invention will be described in detail with reference to the accompanying drawings.

The vibration plate 100 according to the embodiment of the present invention includes hard material layers 10 and an intermediate layer 20 provided between any two adjacent hard material layers 10, at least one intermediate layer 20 being a chopped fiber composite layer; the Young's modulus of hard material layer 10 is greater than 50GPa.

In other words, the vibration plate 100 according to the embodiment of the present invention is mainly composed of the hard material layers 10 and the intermediate layer 20, and the number of the hard material layers 10 may be multiple layers, for example, two layers, three layers, four layers, and the like. As shown in fig. 1, when the number of hard material layers 10 is two, intermediate layer 20 may be located between the two hard material layers 10; when the number of hard material layers 10 is three, for example, the first hard material layer, the second hard material layer, and the third hard material layer are sequentially divided, the number of the intermediate layers 20 may be two, for example, the first intermediate layer and the second intermediate layer, the first intermediate layer may be located between the first hard material layer and the second hard material layer, and the second intermediate layer may be located between the second hard material layer and the third hard material layer. It can be seen that intermediate layer 20 may be located between any two adjacent hard material layers 10.

Further, at least one intermediate layer 20 is a chopped fiber composite layer, for example, the first intermediate layer and/or the second intermediate layer described above is a chopped fiber composite layer. The chopped fibers in the embodiments of the present invention refer to fibers formed by cutting continuous fibers, that is, chopped fibers are manufactured by cutting continuous fibers by definition, and generally have a length of 1mm to 100mm.

In the embodiment of the present invention, the use of chopped fibers is advantageous in forming a hollow integral three-dimensional network, whereas if continuous fibers are used, it is difficult to form a three-dimensional network. Also, the density of the vibration plate 100 is advantageously reduced by using chopped fibers.

In addition, in embodiments of the present invention, intermediate layer 20 is positioned between two hard material layers 10, which is advantageous in withstanding compressive and shear stresses from both sides when a chopped fiber composite layer is used for intermediate layer 20.

In the present embodiment, the Young's modulus of the hard material layer 10 is greater than 50GPa, for example, the Young's modulus of the hard material layer 10 is 51GPa, 55GPa, 60GPa, 80GPa, 100Pa, 150GPa, 200GPa, or the like. In the embodiment of the present invention, the use of the hard material layer 10 having a young's modulus greater than 50GPa is advantageous in improving the rigidity of the entire vibration plate 100 and in enabling the vibration plate 100 to have a high specific modulus.

Thus, the vibration plate 100 according to the embodiment of the invention includes the hard material layer 10 and the intermediate layer 20 disposed between any two adjacent hard material layers 10, and at least one intermediate layer 20 is a chopped fiber composite layer, which is not only beneficial to forming a three-dimensional network structure, but also capable of reducing the density of the vibration plate 100. By employing the hard material layer 10 and the intermediate layer 20 in cooperation, and the young's modulus of the hard material layer 10 being greater than 50GPa, it is advantageous to make the vibration plate 100 light in weight while maintaining high rigidity and high specific modulus of the vibration plate 100.

According to one embodiment of the present invention, the overall density of the vibration plate 100 is 0.05g/cm ³～2.0g/cm³. It should be noted that, if the overall density of the vibration plate 100 is less than 0.05g/cm ³, a relatively complicated processing procedure is required to secure the rigidity and modulus of the vibration plate 100, so that the production cost is easily increased; if the overall density of the vibration plate 100 is more than 2.0g/cm ³, the overall weight of the vibration plate 100 tends to be large. It can be seen that, in the present embodiment, by adopting the vibration plate 100 having the overall density of 0.05g/cm ³～2.0g/cm³, for example, the vibration plate 100 having the overall density of 0.05g/cm³、0.10g/cm³、0.50g/cm³、0.60g/cm³、0.80g/cm³、1.00g/cm³、1.20g/cm³、1.50g/cm³ or 2.0g/cm ³, etc., it is advantageous to reduce the manufacturing cost of the vibration plate 100 while realizing the weight reduction of the vibration plate 100.

According to one embodiment of the invention, the density of the chopped fiber composite layer is 0.1g/cm ³～1.6g/cm³. It should be noted that if the density of the chopped fiber composite layer is less than 0.1g/cm ³, the manufacturing difficulty is high, and the manufacturing cost is easy to increase; and if the density of the chopped strand composite layers is greater than 1.6g/cm ³, it tends to result in a large weight of the vibration plate 100. Furthermore, since the compression modulus and density are positively correlated. Therefore, in the present embodiment, by limiting the density of the chopped fiber composite layer to 0.1g/cm ³～1.6g/cm³, for example, the density of the chopped fiber composite layer to 0.1g/cm³、0.5g/cm³、0.8g/cm³、1.0g/cm³、1.2g/cm³、1.5g/cm³ or 1.6g/cm ³, etc., it is advantageous to achieve both light weight and high rigidity and high flexural modulus of the vibration plate 100.

In some embodiments of the present invention, the total thickness of the chopped fiber composite layer is 20% to 96% of the total thickness of the vibration plate 100. It should be noted that, if the total thickness of the chopped fiber composite layer is less than 20% of the total thickness of the vibration plate 100, the difficulty of reducing the density is increased; if the total thickness of the chopped fiber composite layer is greater than 96% of the total thickness of the vibration plate 100, the thickness of the corresponding hard material layer 10 will be reduced on the basis of the same thickness, increasing the difficulty of securing the rigidity of the vibration plate 100. Therefore, in the present embodiment, the total thickness of the chopped fiber composite layer is 20% to 96% of the total thickness of the vibration plate 100, for example, the total thickness of the chopped fiber composite layer is 20%, 25%, 30%, 40%, 50%, 60%, 70%, 80%, 90% or 96% of the total thickness of the vibration plate 100, which is advantageous in ensuring that the vibration plate 100 has both advantages of light weight and high rigidity.

In some embodiments of the invention, the chopped fiber composite layer has a compression modulus of 50MPa to 2GPa. The chopped fiber composite layer may be moderately compressed because of a certain gap between the fibers of the chopped fiber composite layer. When the chopped fiber composite layer has higher compression modulus, the strain caused by local stress is smaller, so that the stress can be dispersed to all parts of the intermediate layer 20, the deformation of the whole structure of the intermediate layer 20 is reduced, and the structural rigidity of the intermediate layer 20 is improved. However, when the compression modulus of the chopped fiber composite layer is too low, the lower limit of the flexural modulus of the intermediate layer 20 itself is low, and under low stress, the chopped fibers tend to generate large strain, so that the chopped fiber composite layer is difficult to effectively support the high-modulus hard material layer 10, and the high-modulus hard material layer 10 is easy to be driven to deform, so that the intermediate layer 20 is difficult to have an effective supporting effect. In addition, the compression modulus of the chopped fiber composite layer is related to the compression ratio thereof, and the denser the compression, the higher the density, the denser the chopped fibers in the chopped fiber composite layer, and the higher the compression modulus thereof, but the higher the compression thereof, the higher the density thereof, and the difficulty in achieving effective weight reduction for the vibration plate 100.

In addition, the chopped fiber composite layer not only can have a better tensile modulus when compressed to a high density; and may also have a good compression modulus when compressed to an intermediate state (herein intermediate state refers to a state compressed between the highest density and the lowest density), in which state the chopped fiber composite layer does not have a high tensile modulus, but has a low density and the compression modulus may support the intermediate layer 20 to have a good flexural modulus. In practical applications, the middle layer 20 with a better flexural modulus can effectively improve the acoustic performance of the speaker.

It can be seen that in the present embodiment, by employing the chopped fiber composite layer having a compression modulus between 50MPa and 2GPa, for example, the chopped fiber composite layer having a compression modulus of 50MPa, 55Pa, 60MPa, 65MPa, 160MPa, 280MPa, 500MPa, 1GPa, 2GPa, or the like, the intermediate layer 20 is advantageous in having a combination of low density, high rigidity, and high modulus.

According to one embodiment of the present invention, the chopped fiber composite layer is composed of inorganic fibers and synthetic fibers; it should be noted that inorganic fibers have the advantage of high modulus, and synthetic fibers can melt and bind the inorganic fibers together. In forming, the forming temperature may be above the melting point of the synthetic fibers. For example, the inorganic fibers and the synthetic fibers are uniformly mixed, the synthetic fibers play a role similar to a binder, and the inorganic fibers can be adhered together after hot press molding, so that the staggered inorganic fibers form a three-dimensional network structure which is mutually crosslinked, and the support and the shearing resistance are good.

Wherein the inorganic fiber comprises at least one of carbon fiber, basalt fiber, glass fiber, silicon carbide fiber and the like; and/or the synthetic fiber comprises at least one of polypropylene fiber, nylon fiber, polyester fiber, aramid fiber, polyimide fiber, polyethylene fiber, polyacrylonitrile fiber, polyvinyl formal fiber, polyvinyl chloride fiber, polyurethane elastic fiber, polyolefin elastic fiber, and the like. That is, by using the above-described inorganic fiber, it is advantageous to increase the modulus; by adopting the synthetic fiber, the inorganic fiber is favorable for bonding together, and the three-dimensional net structure is favorable for forming.

In some embodiments of the invention, the inorganic fibers have a length center value of 0.5mm to 60mm. The length center value of the inorganic fiber in the embodiment refers to that the inorganic fiber is a long cylindrical member, and the length distance from the center of one end of the long cylindrical member to the center of the other end of the long cylindrical member is the length center value of the inorganic fiber in the embodiment. It should be noted that if the length center value of the inorganic fiber is lower than 0.5mm, the difficulty of forming the grid structure with pores is increased, and the manufacturing cost is increased; if the length center value of the inorganic fiber is more than 60mm, the inorganic fiber is difficult to process, and the manufacturing cost is increased. Therefore, in the present embodiment, the length center value of the inorganic fiber is 0.5mm to 60mm, for example, the length center value of the inorganic fiber is 0.5mm, 1.5mm, 5mm, 10mm, 20mm, 30mm, 40mm, 50mm, 60mm, or the like, which is advantageous in reducing the difficulty of manufacturing the vibration plate 100.

According to one embodiment of the present invention, the inorganic fibers are present in an amount of 10% to 50% by weight of the total volume of the fibers in the chopped fiber composite layer. It should be noted that, by adopting the relationship between the volume content limiting inorganic fiber and the chopped fiber composite layer, the calculation difficulty is reduced, and if the total volume content of the inorganic fiber accounting for the fiber of the chopped fiber composite layer is less than 10%, the difficulty of forming the grid structure with pores is increased, and the manufacturing cost is increased; if the inorganic fibers account for more than 50% of the total volume of the fibers of the chopped fiber composite layer, it is easy to cause that part of the inorganic fibers are difficult to be stuck by the synthetic fibers, and more loose inorganic fibers appear, so that the overall compression modulus is difficult to be further improved. It can be seen that, in this embodiment, the total volume content of the inorganic fibers in the chopped fiber composite layer is 10% -50%, for example, the total volume content of the inorganic fibers in the chopped fiber composite layer is 10%, 20%, 30%, 40%, 45% or 50%, which is beneficial to ensuring high flexural modulus and light weight of the vibration plate 100, and reducing manufacturing difficulty and manufacturing cost.

In some embodiments of the present invention, hard material layer 10 is a metal layer, an inorganic nonmetallic material layer, a carbon fiber prepreg layer, or the like; and/or, hard material layer 10 has a density of 1.2g/cm ³～8.1g/cm³.

In this embodiment, the carbon fiber prepreg layer is a composite layer of carbon fibers and resin, the resin is an organic material, and the carbon fibers are inorganic materials. In this embodiment, by adopting the hard material layers 10 made of multiple materials, the vibration plate 100 product can have different properties, different requirements of the final product can be satisfied, and the manufacturing flexibility and the application universality are improved.

Furthermore, if the density of hard material layer 10 is less than 1.2g/cm ³, the cost of the material will increase; and if the density of hard material layer 10 is greater than 8.1g/cm ³, the cost of the material may also be increased. Therefore, in the present embodiment, when the density of the hard material layer 10 is 1.2g/cm ³、1.5g/cm³、2.2g/cm³、5g/cm³、6g/cm³、7g/cm³ or 8.1g/cm ³, the manufacturing cost is reduced due to the composite requirement of various existing materials.

According to one embodiment of the present invention, the metal layer is at least one of an aluminum film layer, a steel film layer, and the like. The source of the materials is wide, so that the manufacturing cost is reduced by adopting the materials, and the material has mass production property.

In some embodiments of the invention, the inorganic nonmetallic material layer is a glass layer, and the mass content of silicon oxide in the glass layer is 50% -95%; or the inorganic nonmetallic material layer is a ceramic layer, and the ceramic layer is any one of alumina, zirconia, silicon carbide, aluminum nitride, silicon nitride and the like. In the glass layer, the higher the silica content, the higher the hardness, and the better the modulus, but too high a silica content tends to affect the processability. In this embodiment, on the one hand, the non-metal material layer may be a glass layer, and the mass content of the silicon oxide in the glass layer is 50% -95%, for example, the mass content of the silicon oxide in the glass layer is 50%, 60%, 70%, 80%, 90% or 95%, which is beneficial to ensuring the rigidity and workability of the hard material layer 10. In yet another aspect, the high rigidity and high modulus of hard material layer 10 is facilitated by the use of the inorganic nonmetallic material layers described above. In addition, when the inorganic nonmetallic layer adopts an alumina layer, the cost is reduced.

According to one embodiment of the present invention, the total thickness of hard material layer 10 is 2% to 40% of the total thickness of vibration plate 100. It should be noted that if the total thickness of the hard material layer 10 is less than 2% of the total thickness of the vibration plate 100, it is difficult to raise the modulus of the vibration plate 100 at a low cost; if the total thickness of the hard material layer 10 is greater than 40% of the total thickness of the vibration plate 100, it is difficult to further reduce the density of the vibration plate 100. Thus, in the present embodiment, the total thickness of the hard material layer 10 is 2%, 5%, 10%, 15%, 20%, 30%, 35%, 40% or the like of the total thickness of the vibration plate 100, which is advantageous in further increasing the modulus of the vibration plate 100 at a lower cost while reducing the density of the vibration plate 100.

In some embodiments of the present invention, the thickness of each hard material layer 10 is the same, and each hard material layer 10 has a thickness of 5 μm to 500 μm. In this embodiment, for speakers of different specifications, such as micro speakers of tens of millimeters long, to large speakers of tens of centimeters in diameter, different thickness combinations may be selected. For example, micro-speakers may use a thin hard material layer 10, and larger size speakers may use a thick hard material layer 10.

According to one embodiment of the present invention, the thickness of at least one hard material layer 10 is different from the thickness of the other hard material layers 10. For example, when the number of hard material layers 10 is two, the thicknesses of the two hard material layers 10 are different; for another example, when the number of hard material layers 10 is three, the thickness of one hard material layer 10 may be different, or the thickness of two hard material layers 10 may be different, or even the thickness of three hard material layers 10 may be different. In the present embodiment, by adopting hard material layers 10 of different thicknesses, different requirements of rigidity of the vibration plate 100 for different positions can be satisfied.

In some embodiments of the present invention, vibration plate 100 includes three layers, the material of hard material layers 10 on both sides being the same; alternatively, vibration plate 100 includes three layers, and the materials of hard material layers 10 on both sides are different. Where the vibration plate 100 includes three layers, the material of both sides is the hard material layer 10, and the material of the middle is the intermediate layer 20. In this embodiment, when the hard material layers 10 on both sides are the same, the manufacturing cost is reduced; when the hard material layers 10 on the two sides are different, different requirements of rigidity of the vibration plate 100 on different positions are favorably met.

According to one embodiment of the present invention, the vibration plate 100 includes a steel film layer, a chopped fiber composite layer, and a steel film layer that are sequentially stacked. That is, in this embodiment, the hard material layer 10 may be a steel film layer, and the intermediate layer 20 may be a chopped fiber composite layer. In the present embodiment, by adopting the steel film layer, the fabrication of the vibration plate 100 is facilitated, and the high flexural modulus and the high rigidity of the vibration plate 100 are ensured.

In some embodiments of the present invention, vibration plate 100 includes five layers with a chopped fiber composite layer disposed between any two adjacent hard material layers 10. For example, hard material layer 10-intermediate layer 20-hard material layer 10 are sequentially from top to bottom. In the present embodiment, by adopting the five-layer structure, the fabrication of the vibration plate 100 having a thicker thickness is facilitated, while the vibration plate 100 is made to have both light weight and high flexural modulus and high rigidity.

In some embodiments of the present invention, the intermediate layer 20 has a tackifying component, such as an internal portion of chopped fibers.

According to one embodiment of the present invention, vibration plate 100 further includes an adhesive layer between hard material layer 10 and the chopped fiber composite layer to connect hard material layer 10 and the chopped fiber composite layer; alternatively, the adhesive layer has a thickness of 1 μm to 200 μm. In this embodiment, the use of an adhesive layer is advantageous in reducing the difficulty of the connection between hard material layer 10 and intermediate layer 20. In addition, the thickness of the adhesive layer is 1 μm to 200 μm, for example, the thickness of the adhesive layer is 1 μm,10 μm, 50 μm, 100 μm, 120 μm, 150 μm, 180 μm, 200 μm, or the like, which is advantageous in reducing the difficulty of connection between the hard material layer 10 and the intermediate layer 20 and also in ensuring a thinner thickness of the vibration plate 100.

Thus, according to the vibration plate 100 of the embodiment of the present invention, by using the hard material layers 10 and the intermediate layers 20 provided between any two adjacent hard material layers 10, at least one intermediate layer 20 is a chopped fiber composite layer; the Young's modulus of the hard material layer 10 is greater than 50GPa, which is advantageous for ensuring that the vibration plate 100 has both light weight, high flexural modulus and high rigidity.

The present invention also provides a diaphragm assembly including a diaphragm and the diaphragm 100 of any of the above embodiments. Since the vibration plate 100 of the embodiment of the present invention has the above advantages, the vibration film assembly of the embodiment of the present invention also has the above advantages, such as light weight, high flexural modulus, high rigidity, etc., which are not described herein.

The invention also provides a sound generating device which comprises the vibrating diaphragm assembly of any embodiment. For example, the sound generating device includes a diaphragm assembly, a magnetic circuit system, and the like. Because the vibrating diaphragm assembly has the advantages of light weight, high bending modulus, high rigidity and the like, the sound generating device can also improve the sound generating effect while light weight.

The diaphragm 100, the diaphragm assembly, and the sound generating device according to the embodiment of the present invention will be described in detail with reference to the following embodiments.

Example 1

Vibration plate 100 includes three layers, the material of hard material layers 10 on both sides being the same. The vibration plate 100 includes a steel film layer-chopped fiber composite layer-steel film layer stacked in this order.

Wherein the compression modulus of the chopped fiber composite layer is 83MPa, the density of the chopped fiber composite layer is 0.4g/cm ³, the thickness of the chopped fiber composite layer is 250 μm, and the ratio of the thickness of the chopped fiber composite layer to the total thickness of the vibration plate 100 is 86.2%. The chopped fiber composite layer consists of inorganic fibers and synthetic fibers; wherein the inorganic fiber is chopped carbon fiber; the synthetic fibers are chopped polypropylene fibers. The length center value of the inorganic fiber was 5mm. The total volume content of the inorganic fibers in the chopped fiber composite layer was 30%.

Furthermore, hard material layer 10 is a steel film layer; the density of hard material layer 10 is 7.9g/cm ³; the Young's modulus of hard material layer 10 was 210GPa. The total thickness of hard material layer 10 is 13.7% of the total thickness of vibration plate 100. The thickness of each hard material layer 10 is the same, and the thickness of each hard material layer 10 is 20 μm.

The vibration plate 100 of example 1 has a thickness of 0.29mm and a circular shape. After testing, the following test results were obtained:

(1) The diaphragm 100 had an overall gram weight of 416g/m ², a density of 1.43g/cm ³, a flexural modulus of 45GPa, and a specific modulus of 31 GPa/(g/cm ³). It can be seen that the product of example 1 combines light weight, high flexural modulus and high rigidity.

(2) The diaphragm 100 of example 1 was applied to a cone of a speaker, the high-frequency cut-off frequency of the speaker was 16.5KHz, and the sensitivity was 86dB. It can be seen that the speaker including the vibration plate 100 product of embodiment 1 has good acoustic performance.

Example 2

Vibration plate 100 includes three layers, the material of hard material layer 10 being different on both sides. The vibration plate 100 includes an upper hard material layer, a chopped fiber composite layer, and a lower hard material layer, which are sequentially stacked. The upper hard material layer is a steel film layer with the thickness of 20 mu m, and the lower hard material layer is an aluminum film layer with the thickness of 20 mu m. That is, example 2 includes a steel film layer-chopped fiber composite layer-aluminum film layer stacked in this order.

Moreover, the density of the upper hard material layer (steel film layer) is 7.9g/cm ³; the density of the lower hard material layer (aluminum film layer) was 2.7g/cm ³. The Young's modulus of the upper hard material layer was 210GPa, and the Young's modulus of the lower hard material layer was 70GPa. The sum of the thicknesses of the upper hard material layer and the lower hard material layer is 13.7% of the total thickness of the vibration plate 100. The thickness of the steel film layer and the aluminum film layer are the same and are 20 mu m.

The thickness of the vibration plate 100 of example 2 was 0.29mm, and the shape was the same circular shape as in example 1. After testing, the following test results were obtained:

(1) The diaphragm 100 has an overall gram weight of 312g/m ², a density of 1.076g/cm ³, a flexural modulus of 23GPa, and a specific modulus of 21.37 GPa/(g/cm ³). It can be seen that the product of example 2 combines light weight, high flexural modulus and high rigidity.

(2) The diaphragm 100 of example 2 was applied to a cone of a speaker, the high frequency cut-off frequency of the speaker was 13.5KHz, and the sensitivity was 88dB. It can be seen that the speaker including the vibration plate 100 product of embodiment 2 has good acoustic performance.

Example 3

The vibration plate 100 includes five layers, each of which has the same material as the hard material layer 10 and each of which has the same material as the intermediate layer 20. Specifically, the vibration plate 100 includes a steel film layer-a chopped fiber composite layer-a steel film layer, which are stacked in this order.

Wherein the intermediate layer 20 is a chopped fiber composite layer having a compression modulus of 83MPa, a density of 0.4g/cm ³, a thickness of 125 μm per layer, a total thickness of 250 μm, and a total thickness of 80.6% of the total thickness of the vibration plate 100. The chopped fiber composite layer consists of inorganic fibers and synthetic fibers; wherein the inorganic fiber is chopped carbon fiber; the synthetic fibers are chopped polypropylene fibers. The length center value of the inorganic fiber was 5mm. The total volume content of the inorganic fibers in the chopped fiber composite layer was 30%.

Moreover, each hard material layer 10 is a steel film layer, and the density of each hard material layer 10 is 7.9g/cm ³; the Young's modulus of each hard material layer 10 was 210GPa. The total thickness of hard material layer 10 is 19.4% of the total thickness of vibration plate 100. The thickness of each hard material layer 10 is the same, and the thickness of each hard material layer 10 is 20 μm.

The vibration plate 100 of example 3 has a thickness of 0.31mm and a circular shape similar to that of example 1. After testing, the following test results were obtained:

(1) The diaphragm 100 had an overall grammage of 574g/m ², a density of 1.85g/cm ³, a flexural modulus of 51GPa, and a specific modulus of 27.6 GPa/(g/cm ³). It can be seen that the product of example 3 combines light weight, high flexural modulus and high rigidity.

(2) The diaphragm 100 of example 3 was applied to a cone of a speaker, the high-frequency cut-off frequency of the speaker was 15KHz, and the sensitivity was 81dB. It can be seen that the speaker including the vibration plate 100 product of embodiment 3 has good acoustic performance.

Example 4

The vibration plate 100 includes a steel film layer, a chopped fiber composite layer, and a steel film layer stacked in this order. The steel film layers and the chopped fiber composite layers on the two sides are respectively connected through bonding layers, the bonding layers are made of acrylic resin, and the thickness of the bonding layers is 5 mu m. Specifically, the vibration plate 100 includes a steel film layer-an adhesive layer-a chopped fiber composite layer-an adhesive layer-a steel film layer.

Wherein the compression modulus of the chopped fiber composite layer was 83MPa, the density of the chopped fiber composite layer was 0.4g/cm ³, the thickness of the chopped fiber composite layer was 250 μm, and the total thickness of the chopped fiber composite layer vibration plate 100 was 83.3%. The chopped fiber composite layer consists of inorganic fibers and synthetic fibers; wherein the inorganic fiber is chopped carbon fiber; the synthetic fibers are chopped polypropylene fibers. The length center value of the inorganic fiber was 5mm. The total volume content of the inorganic fibers in the chopped fiber composite layer was 30%.

Furthermore, hard material layer 10 is a steel film layer; the density of hard material layer 10 is 7.9g/cm ³; the Young's modulus of hard material layer 10 was 210GPa. The total thickness of hard material layer 10 is 13.3% of the total thickness of vibration plate 100. The thickness of each hard material layer 10 is the same, and the thickness of each hard material layer 10 is 20 μm.

The vibration plate 100 of example 4 has a thickness of 0.3mm and a circular shape similar to that of example 1. After testing, the following test results were obtained:

(1) The diaphragm 100 had an overall gram weight of 428g/m ², a density of 1.427g/cm ³, a flexural modulus of 43GPa, and a specific modulus of 30.1 GPa/(g/cm ³). It can be seen that the product of example 4 combines light weight, high flexural modulus and high rigidity.

(2) The diaphragm 100 of example 4 was applied to a cone of a speaker, the high-frequency cut-off frequency of the speaker was 13.5KHz, and the sensitivity was 88dB. It can be seen that the speaker including the vibration plate 100 product of embodiment 4 has good acoustic performance.

Example 5

Vibration plate 100 includes three layers, the material of hard material layers 10 on both sides being the same. The vibration plate 100 includes an alumina ceramic layer-chopped fiber composite layer-alumina ceramic layer stacked in this order.

Furthermore, hard material layer 10 is an alumina ceramic layer; the density of hard material layer 10 is 3.5g/cm ³; the Young's modulus of hard material layer 10 was 390GPa. The total thickness of hard material layer 10 is 13.8% of the total thickness of vibration plate 100. The thickness of each hard material layer 10 is the same, and the thickness of each hard material layer 10 is 20 μm.

The vibration plate 100 of example 5 has a thickness of 0.29mm and a circular shape similar to that of example 1. After testing, the following test results were obtained:

(1) The diaphragm 100 has an overall gram weight of 240g/m ², a density of 0.827g/cm ³, a flexural modulus of 76GPa, and a specific modulus of 91 GPa/(g/cm ³). It can be seen that the product of example 5 combines light weight, high flexural modulus and high rigidity.

(2) The diaphragm 100 of example 5 was applied to a cone of a speaker with a high frequency cut-off frequency of higher than 20KHz and a sensitivity of 88.5dB. It can be seen that the speaker including the vibration plate 100 product of embodiment 5 has good acoustic performance.

Example 6

Vibration plate 100 includes three layers, the material of hard material layers 10 on both sides being the same. The vibration plate 100 includes two unidirectional carbon fiber prepregs, a chopped fiber composite layer, and two unidirectional carbon fiber prepregs stacked in this order, and the extending directions of the two unidirectional carbon fiber prepregs are perpendicular to each other, specifically, the vibration plate 100 of embodiment 6 includes 0 ° upper unidirectional carbon fiber prepreg/90 ° lower unidirectional carbon fiber prepreg-chopped fiber composite layer-0 ° upper unidirectional carbon fiber prepreg/90 ° upper unidirectional carbon fiber prepreg.

Wherein the compression modulus of the chopped fiber composite layer is 81MPa, the density of the chopped fiber composite layer is 0.37g/cm ³, the thickness of the chopped fiber composite layer is 270 μm, and the thickness of the chopped fiber composite layer is 77.1% of the total thickness ratio of the vibration plate 100. The chopped fiber composite layer consists of inorganic fibers and synthetic fibers; wherein the inorganic fiber is chopped carbon fiber; the synthetic fibers are chopped polypropylene fibers. The length center value of the inorganic fiber was 5mm. The total volume content of the inorganic fibers in the chopped fiber composite layer was 30%.

Furthermore, hard material layer 10 is a carbon fiber prepreg layer; the density of hard material layer 10 is 1.8g/cm ³; the Young's modulus of hard material layer 10 was 86GPa. The total thickness of hard material layer 10 is 22.9% of the total thickness of vibration plate 100. The thickness of each hard material layer 10 is the same, and the thickness of each hard material layer 10 is 40 μm.

Further, the carbon fiber prepreg layer contains carbon fibers and a prepreg resin, wherein the content of the carbon fibers is 100 parts by weight and the content of the prepreg resin is 53.8 parts by weight. The tensile modulus of the carbon fibers of the carbon fiber prepreg was 230GPa. The carbon fiber prepreg layer comprises two layers of unidirectional carbon fibers, and the gram weight of the unidirectional carbon fibers is 36 g/square meter.

The vibration plate 100 of example 6 has a thickness of 0.35mm and a circular shape similar to that of example 1. After testing, the following test results were obtained:

(1) The diaphragm 100 had an overall gram weight of 244g/m ², a density of 0.697g/cm ³, a flexural modulus of 24GPa, and a specific modulus of 34.4 GPa/(g/cm ³). It can be seen that the product of example 6 combines light weight, high flexural modulus and high rigidity.

(2) The diaphragm 100 of example 6 was applied to a cone of a speaker, the high-frequency cut-off frequency of the speaker was 17KHz, and the sensitivity was 88.5dB. It can be seen that the speaker including the vibration plate 100 product of embodiment 6 has good acoustic performance.

Comparative example 1

The vibration structure plate includes a chopped fiber composite structure layer having a compression modulus of 51MPa, a density of 0.285g/cm ³, and a total thickness of the chopped fiber composite structure layer accounting for 100% of a total thickness of the vibration plate. The chopped fiber composite structure layer consists of chopped carbon fibers and synthetic fibers, wherein the length of the chopped carbon fibers is 5mm; the volume of the chopped carbon fibers was 30% of the total volume of the fibers in the chopped fiber composite structure layer. The synthetic fibers are chopped polypropylene fibers. The gram weight of the chopped fiber composite structural layer was 100 g/square meter.

The vibration structure plate in comparative example 1 had a thickness of 0.35mm and a shape of a circle identical to that of example 1. After testing, the following test results were obtained:

(1) The overall gram weight of the vibration structure plate was 100g/m ², the density was 0.285g/cm ³, the flexural modulus was 1.2GPa, and the specific modulus was 4.2 GPa/(g/cm ³). As can be seen, the product of comparative example 1 has a very low flexural modulus and lacks strength.

(2) The vibration structure plate of comparative example 1 was applied to a cone of a speaker whose high-frequency cut-off frequency was 5.5KHz and sensitivity was 90dB. It can be seen that the high frequency cut-off frequency of comparative example 1 is very low, and it is difficult to satisfy the daily application conditions.

Comparative example 2

The vibration structure plate comprises a hard structure layer, wherein the hard structure layer is a steel film layer. The density of the hard structural layer was 7.9g/cm ³, and the Young's modulus of the hard structural layer was 210GPa.

The vibration structure plate of comparative example 2 had a thickness of 0.29mm and a shape of a circle identical to that of example 1. After testing, the following test results were obtained:

(1) The overall gram weight of the vibration structure plate was 2291g/m ², the density was 7.9g/cm ³, the flexural modulus was 210GPa, and the specific modulus was 26.7 GPa/(g/cm ³). It can be seen that the density of comparative example 2 is very high.

(2) The high-frequency cut-off frequency of the loudspeaker is 16.5KHz, the sensitivity is 45dB, and the product of comparative example 2 is heavy and difficult to sound.

Comparative example 3

The vibration structure plate comprises three layers, and the materials of the hard structure layers at two sides are the same. The vibration structure plate comprises a steel film layer, namely a TPU (thermoplastic polyurethane) -steel film layer which are sequentially overlapped.

Wherein the compression modulus of the TPU is 41MPa, the density of the TPU is 1.2g/cm ³, the thickness of the TPU is 250 mu m, and the thickness of the TPU accounts for 86.2% of the total thickness of the vibration structure plate.

Moreover, the hard structural layer is a steel film layer; the density of the hard structural layer is 7.9g/cm ³; the Young's modulus of the hard structural layer was 210GPa. The total thickness of the hard structural layer is 13.8% of the total thickness of the vibrating structural plate. The thickness of each hard structural layer was the same, and the thickness of each hard structural layer was 20. Mu.m.

The vibration structure plate of comparative example 3 had a thickness of 0.29mm and a shape of a circle identical to that of example 1. After testing, the following test results were obtained:

(1) The overall gram weight of the vibrating structural plate was 618.4g/m ², the density was 2.13g/cm ³, the flexural modulus was 39GPa, and the specific modulus was 18.3 GPa/(g/cm ³). It can be seen that the product of comparative example 3 has a higher density and a lower specific modulus.

(2) The high-frequency cut-off frequency of the loudspeaker is 12.5KHz, and the sensitivity is 75dB. It can be seen that the sensitivity of comparative example 3 is low and sounding is difficult.

Comparative example 4

The vibration structure plate comprises three layers, and the materials of the hard structure layers at two sides are the same. The vibration structure plate comprises a magnesium-lithium alloy layer, a chopped fiber composite structure layer and a magnesium-lithium alloy layer which are sequentially overlapped.

Wherein the compression modulus of the chopped fiber composite layer is 81MPa, the density of the chopped fiber composite layer is 0.37g/cm ³, the thickness of the chopped fiber composite layer is 270 μm, and the thickness of the chopped fiber composite layer is 77.1% of the total thickness ratio of the vibration plate. The chopped fiber composite layer consists of inorganic fibers and synthetic fibers; wherein the inorganic fiber is chopped carbon fiber; the synthetic fibers are chopped polypropylene fibers. The length center value of the inorganic fiber was 5mm. The volume of the inorganic fibers is 30% of the total volume of the fibers in the chopped strand composite layer.

The hard structure layer is a magnesium-lithium alloy layer; the density of the hard structural layer is 1.6g/cm ³; the Young's modulus of the hard structural layer was 40GPa. The total thickness of the hard structural layer was 22.9% of the total thickness of the vibrating structural plate. The thickness of each hard structural layer was the same, and the thickness of each hard structural layer was 20. Mu.m.

The vibration structure plate of comparative example 4 had a thickness of 0.29mm and a shape of a circle identical to that of example 1. After testing, the following test results were obtained:

(1) The overall gram weight of the vibrating structural plate was 164g/m ², the density was 0.566g/cm ³, the flexural modulus was 8.5GPa, and the specific modulus was 15 GPa/(g/cm ³). It can be seen that the product of comparative example 4 has a lower modulus and a lower specific modulus.

(2) The high-frequency cut-off frequency of the loudspeaker is 11KHz, and the sensitivity is 89dB when the high-frequency cut-off frequency is applied to the cone basin of the loudspeaker. It can be seen that the high frequency cut-off frequency of comparative example 4 is low.

Comparative example 5

In comparative example 5, a circular cone having the same shape as in example 1 was used, and the diaphragm and the speaker were measured, respectively, to obtain the following data:

(1) The cone has a thickness of 0.5mm, a density of 0.6g/cm ³, a flexural modulus of 3GPa, a loss factor of 0.02, and poor damping.

(2) The high-frequency cut-off frequency of the loudspeaker is 8KHz, the sensitivity is 88dB, the middle-high frequency distortion is less than 2%, and the visible high-frequency cut-off frequency is low, namely the high-frequency expansion difference.

Comparing example 1 with comparative example 5, the high frequency cutoff frequency of example 1 was higher than that of the cone.

Comparing example 2 with comparative example 5, the sensitivity of example 2 is close to that of the cone, but the high frequency cut-off frequency is much higher than that of the cone.

Comparing example 3 with comparative example 5, the high frequency cutoff frequency of example 3 was much higher than that of the cone.

Comparing example 4 with comparative example 5, the high frequency cut-off frequency is much higher than the cone, although the sensitivity is close to the cone. In addition, the interlayer bonding force of example 4 was better.

Comparing example 5 with comparative example 5, the sensitivity of example 5 is higher than that of the cone.

Comparing example 6 with comparative example 5, the high frequency cutoff frequency of example 6 was much higher than that of the cone.

Comparative example 6

In comparative example 6, a circular aluminum tub having the same shape as in example 1 was used, and the diaphragm and the speaker were measured, respectively, to obtain the following data:

(1) The thickness is 0.35mm, the density is 2.7g/cm ³, the flexural modulus is 70GPa, and the loss factor is 0.002;

(2) The high-frequency cut-off frequency of the loudspeaker is 16KHz, the sensitivity is 75dB, and the middle-high frequency distortion is less than 2%.

Comparing example 1 with comparative example 6, example 1 has higher sensitivity than the aluminum basin and also has a higher cut-off frequency than the aluminum basin.

Comparing example 3 with comparative example 6, example 3 has a higher sensitivity than a pure aluminum cone.

Comparing example 5 with comparative example 6, the sensitivity of example 5 is higher than that of the aluminum basin, and the high frequency cut-off frequency is also much higher than that of the aluminum basin.

In addition, as shown in fig. 2, under the condition of close sensitivity, the high-frequency expansion advantage of the product of the embodiment is obvious, and the effective frequency response range is wider.

In summary, the vibration plate 100 according to the embodiment of the present invention includes the hard material layer 10 and the intermediate layer 20 disposed between any two adjacent hard material layers 10, and at least one intermediate layer 20 is a chopped fiber composite layer, which is not only beneficial to forming a three-dimensional network structure, but also capable of reducing the density of the vibration plate 100. By employing the hard material layer 10 and the intermediate layer 20 in cooperation, and the young's modulus of the hard material layer 10 being greater than 50GPa, it is advantageous to make the vibration plate 100 light in weight while maintaining high rigidity and high specific modulus of the vibration plate 100.

While certain specific embodiments of the invention have been described in detail by way of example, it will be appreciated by those skilled in the art that the above examples are for illustration only and are not intended to limit the scope of the invention. It will be appreciated by those skilled in the art that modifications may be made to the above embodiments without departing from the scope and spirit of the invention. The scope of the invention is defined by the appended claims.

Claims

1. The vibrating plate is characterized by comprising hard material layers and an intermediate layer arranged between any two adjacent hard material layers, wherein at least one intermediate layer is a chopped fiber composite layer;

Wherein the Young's modulus of the hard material layer is greater than 50GPa.

2. The vibration plate according to claim 1, wherein the vibration plate has an overall density of 0.05g/cm ³～2.0g/cm³.

3. The vibration plate of claim 1, wherein the chopped fiber composite layer has a density of 0.1g/cm ³～1.6g/cm³.

4. The vibration plate of claim 1, wherein the total thickness of the chopped fiber composite layer is 20% to 96% of the total thickness of the vibration plate.

5. The vibration plate according to claim 1, wherein the compression modulus of the chopped fiber composite layer is 50MPa to 2GPa.

6. The vibration plate according to claim 1, wherein the chopped fiber composite layer is composed of inorganic fibers and synthetic fibers;

wherein the inorganic fiber comprises at least one of carbon fiber, basalt fiber, glass fiber and silicon carbide fiber; and/or the number of the groups of groups,

The synthetic fiber comprises at least one of polypropylene fiber, nylon fiber, polyester fiber, aramid fiber, polyimide fiber, polyethylene fiber, polyacrylonitrile fiber, polyvinyl formal fiber, polyvinyl chloride fiber, polyurethane elastic fiber and polyolefin elastic fiber.

7. The vibration plate according to claim 6, wherein the inorganic fiber has a length center value of 0.5mm to 60mm.

8. The vibration plate according to claim 6, wherein the content of the inorganic fibers in the total volume of the fibers in the chopped fiber composite layer is 10 to 50%.

9. The vibration plate according to any one of claims 1-8, wherein the hard material layer is a metal layer, an inorganic nonmetallic material layer, or a carbon fiber prepreg layer; and/or the hard material layer has a density of 1.2g/cm ³～8.1g/cm³.

10. The vibration plate of claim 9, wherein the metal layer is at least one of an aluminum film layer and a steel film layer.

11. The vibration plate according to claim 9, wherein the inorganic nonmetallic material layer is a glass layer, and the mass content of silicon oxide in the glass layer is 50% -95%;

Or the nonmetallic material layer is a ceramic layer, and the ceramic layer is any one of alumina, zirconia, silicon carbide, aluminum nitride and silicon nitride.

12. The vibration plate according to claim 9, wherein the total thickness of the hard material layer is 2% to 40% of the total thickness of the vibration plate.

13. The vibration plate of claim 9, wherein the thickness of each hard material layer is the same, and each hard material layer has a thickness of 5 μm to 500 μm.

14. The vibration plate of claim 9, wherein at least one of the hard material layers has a thickness that is different from the thickness of the other hard material layers.

15. The diaphragm of claim 10 wherein the diaphragm comprises three layers, the material of the hard material layers on both sides being the same;

Or the vibration plate comprises three layers, and the materials of the hard material layers at two sides are different.

16. The diaphragm of claim 15 wherein the diaphragm comprises the steel film layer, the chopped fiber composite layer, and the steel film layer stacked in that order.

17. The diaphragm of claim 9 wherein the diaphragm comprises five layers, the chopped fiber composite layer being disposed between any two adjacent layers of the hard material.

18. The vibration plate according to claim 1, characterized by further comprising:

An adhesive layer between the hard material layer and the chopped fiber composite layer to connect the hard material layer and the chopped fiber composite layer; the thickness of the adhesive layer is 1-200 mu m.

19. A diaphragm assembly comprising a diaphragm and a diaphragm according to any one of claims 1 to 18.

20. A sound generating apparatus comprising the diaphragm assembly of claim 19.